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Obstructive sleep apnoea (OSA) is characterised by repetitive episodes of upper airway obstruction during sleep leading to hypoxia and sleep fragmentation. Prevalence rates in the paediatric population vary between 1.2% to 5.7%.[[1]] When symptoms of apnoea are recorded separately from snoring, snoring is more common (1%–2% versus 3.6%–7.7% for always snoring and 9.6% to 21.2% for habitual snoring).[[2]] Both complete obstruction (apnoea) and partial obstruction (hypopnoea) are associated with oxygen desaturation and arousal in children. The commonest cause is adenotonsillar hypertrophy, but obesity is increasingly being associated with OSA in later childhood and adolescence. Other risk factors include craniofacial anomalies, neuromuscular disorders, congenital/chromosomal syndromes (most commonly trisomy 21) and central nervous system disorders.[[3,4]]

The prevalence of OSA in the child and youth population of Aotearoa New Zealand is not known. In a community sample of 839 3-year-old children, of whom around half were followed up at 7 years of age, prevalence of habitual snoring was similar at the two time points (11.3% versus 9.2%) but there were individual changes in status over time, highlighting the need for regular screening for symptoms including after adenotonsillectomy.[[5]] Untreated OSA has been associated with impairments in memory and attention, learning deficits and difficult behaviour and so attention to treatment is important.[[6]] Obstructive sleep apnoea can lead to daytime sleepiness and hyperactive behaviour. At night, sleep is restless and waking common with consequent secondary effects on caregivers including sleep disturbance, fatigue and mood changes.

The first line of treatment in children, adenotonsillectomy, improves quality of life but may not resolve all symptoms in all children.[[7–9]] Those with predisposing factors such as obesity, craniofacial anomalies and neuromuscular or other congenital syndromes may require alternative treatments such as continuous positive airway pressure (CPAP).

Paediatric sleep services are well established in the main centres in Australia. Currently in Aotearoa New Zealand, only Wellington and Auckland have established services for paediatric sleep studies reported by a paediatric sleep physician, although a developing specialist service is now available in Christchurch with the recent arrival of a paediatric specialist trained in sleep medicine. In 2005, colleagues at Starship hospital Auckland reported on non-invasive ventilation use in the paediatric population in New Zealand including 47 patients on CPAP.[[4]] A trend was noted then of increasing numbers of children receiving respiratory support at home. In 2013, the Australasian Paediatric Respiratory Group reported data on paediatric home ventilatory support across Australasia, providing estimates of numbers using CPAP and expressing concern about data quality and equity of access to services.[[10]]

The collaboration between Capital and Coast DHB (CCDHB) and the University of Otago WellSleep adult sleep laboratory started in 1997. Initially, with regard to the paediatric age range, there was more emphasis on neonatal polysomnography (PSG) and research in infant breathing. Paediatric sleep clinics commenced at CCDHB in 2005 and were led by a qualified paediatric sleep physician from 2008. Since then, a growing number of children have been seen, assessed and offered CPAP therapy. This review aimed to determine the effectiveness of the establishment of CPAP treatment in children within the Wellington Region, and to see if there had been improvements over the last 15 years. We also examined the reasons for CPAP treatment and associated demographic factors.

Method

This was a retrospective review of paediatric sleep service records at CCDHB including clinic letters and PSG studies to identify all children offered CPAP treatment from November 2005 to December 2020. CCDHB contracts paediatric sleep assessment services also for Hutt Valley and Wairarapa DHBs from the WellSleep sleep laboratory at the University of Otago, Wellington. Data were collected on demographics, medical diagnoses, indications for respiratory support, Ear Nose and Throat (ENT) specialist involvement and surgery. The NZ Deprivation Index was calculated from NZDep2013 or NZDep2018 data depending on when the patient was first seen.[[11,12]] A BMI at or above the 95th percentile for age and gender was considered overweight. Factors related to CPAP use were also recorded including the year first seen by the service, number of PSG studies undertaken and initial apnoea hypopnea index (AHI).

Compliance was assessed from clinical information rather than machine downloads, as the availability of these changed over the review period. Compliance was documented as either “usually good” (patient using CPAP for >4 hours each night for >70% of the week), “good” (patient using CPAP 50% of the week), “variable” (intermittent use of CPAP) or “poor” (patient never established on CPAP). A “failed trial” was recorded if the patient had not completed the initial one-month CPAP trial. A “declined trial” was recorded if the family did not take up the offer of CPAP treatment. Patient characteristics and compliance were compared between two time periods, 2005–2014 and 2015–2020. Data were collated into a Microsoft Excel database, and summary statistics generated using Excel functions. The audit was approved by the Child Health Service governance group at CCDHB.

Results

Seventy-four patients were offered CPAP therapy over the time period, of whom 52 (70%) were male. Age at commencement varied between less than one year of age to 23 years of age, the latter being a Down syndrome patient. Patients were offered CPAP across the child and youth age range with 12 cases being ≥16 years of age. (Figure 1). Patient demographics are shown in Table 1. NZ European cases were under-represented and Pacific and Other ethnicities over-represented.

View Table 1.

Figure 1: Age at which CPAP was first offered or commenced.

The Deprivation Index quintile for cases is illustrated in Table 1. Although all quintiles were represented, the highest number of cases were from Quintile 5. This is not representative of data for the <15-year age group from Capital and Coast, Hutt Valley and Wairarapa district health boards (DHBs), where Quintile 4 is the predominant quintile for Hutt Valley and Wairarapa and Quintile 1 for Capital and Coast DHB.[[13]] Forty-five (61%) patients were from Capital and Coast DHB, 24 (33%) from Hutt Valley DHB, three (4%) from Wairarapa DHB and one (1%) each from Whanganui and Nelson Marlborough DHBs.

Patients were initiated on CPAP therapy every year from 2005 to 2020. Early on in the time period, two Wellington patients were started on CPAP at Auckland Starship hospital. Three other patients commenced CPAP elsewhere and then transferred to Wellington because of a change in personal circumstances. There was a marked increase in numbers of patients offered CPAP treatment over the audit period (Figure 2).

The mean Body Mass Index (BMI) when offered CPAP therapy was 30.6 kg/m[[ 2]] (SD 11.9), ranging from 13.1kg/m2 to 68.6kg/m2. BMI was unavailable for three patients. There were 40 (54%) patients with a BMI >95th centile for age. The mean BMI was higher for Māori and Pacific patients than for NZ European patients (Table 1). Obesity was the most commonly documented co-morbidity contributing to the need for CPAP treatment followed by Down syndrome and craniofacial anomalies (Table 2).

Figure 2: Year CPAP offered or commenced.

The most common sleep diagnosis resulting in offering CPAP was OSA (69 (82%) patients). Three patients had a mixed picture of central and obstructive apnoea on PSG, and one patient had evidence of OSA with a degree of hypoventilation. A further patient had catathrenia without significant OSA on overnight PSG. Diagnostic PSG was unavailable for five (18%) patients. For the remainder, six had an apnoea hypopnoea index (AHI) between 1–5 events per hour, 13 had an AHI between 5–9 events per hour, and 11 had an AHI between 0–14 events per hour. The remaining 39 patients had an AHI ≥15 events per hour with four having an AHI >90 events per hour. Some patients had a full night diagnostic study, and some had a split study with a shorter diagnostic period and CPAP applied during the night of the initial study, which would explain some variation in the initial AHI.

Twenty-nine (39%) patients had at least one type of ENT procedure prior to CPAP treatment. The most common procedure was adenotonsillectomy (n=20) followed by other nasal surgery (n=7), adenotonsillectomy plus revision adenoidectomy (n=4), tonsillectomy alone (n=3) and adenoidectomy alone (n=1). Seven patients had two procedures and three patients had three procedures. There were also a number of patients who had ENT procedures after being offered CPAP. These procedures included adenotonsillectomy (n=9), other nasal surgery (n=6), tonsillectomy (n=5), revision adenoidectomy (n=3) and lingual tonsillectomy (n=1).

With regard to acceptance of treatment, one family declined the offer of CPAP treatment, and eight patients did not complete the initial trial period. The eight patients not completing the CPAP trial were all ≥10 years of age as was the patient for whom a CPAP trial was declined. Compliance data are shown in Table 3.

When age was considered for patients using CPAP beyond a month, the best compliance was seen in the 0–4 year age group. When ethnicity was considered, Māori patients appeared less likely to have good or usually good compliance. For those patients who completed the one-month trial, good/usually good compliance was more commonly documented in the second time period.

During CPAP treatment, overnight PSG recordings were undertaken for monitoring pressure requirements over time. The average number of studies per patient, including the initial diagnostic study, was 2.5 studies (median 2, range 1–11). Younger children continuing CPAP over a longer period of time had studies undertaken every one to two years to review pressure requirements.

By the end of 2020, 54 patients were discharged from the service or stopped using CPAP and 20 patients remained current patients. Reasons for discharge are shown in Table 4. The most common reasons for discharge were poor tolerance and compliance (n=13) and transfer to adult sleep services (n=12). Nine patients demonstrated an improvement in OSA symptoms after ENT surgery and six improved for other reasons. Some of these were infants who demonstrated improvement in micrognathia during the first year of life.

View Tables 2–4.

Discussion

This review of patients managed through the paediatric sleep service at CCDHB indicates the wide range of ages and underlying diagnoses of children presenting with OSA and requiring treatment with CPAP. Also, just as there has been an explosion of CPAP use for adult patients in recent years, so also in the infant, child and youth age range an increasing number of patients are being treated with CPAP. These cases are likely just the tip of the iceberg in regard to the numbers who would benefit from this treatment. The increased referrals suggest greater recognition by a range of clinicians that CPAP may be a useful treatment for these patients.

The most common indication for CPAP commencement was, as expected, OSA and the most common primary clinical associations were obesity (without other co-morbid factors), Down syndrome and craniofacial abnormalities. Children with neurological disorders compromising upper airway function during sleep are also increasingly being referred for consideration of CPAP. These findings are similar in some respects to the Starship hospital study reporting on 108 children started on CPAP between 1999 to 2004.[[4]] The most common indication for respiratory support in the Auckland cohort was respiratory airway disease followed by neuromuscular disease and central nervous system disorder. Obesity was “not a common indication”. Machalaani et al. reported in 2016 on the effectiveness of CPAP in 55 children 0–18 years of age from the Children’s Hospital at Westmead in Sydney.[[14]] Just under 90% of CPAP users were in diagnostic categories grouped as chromosomal, neuromuscular, lung disorder, central nervous system disorder or “other” disorder. Only five CPAP users were documented as being obese.

In contrast, just over half the patients in the current study had a BMI >95th centile. For 29% of the group, obesity was the main reason for the OSA whereas for others the obesity was a co-morbidity in association with diagnoses such as Prader–Willi syndrome, Down syndrome and Duchenne muscular dystrophy. The current data therefore suggest that although CPAP is being used for patients with a wide variety of diagnoses as previously documented, its use is increasing in children and youth with obesity without other clinical co-morbidities. It is not clear why the current data are different from Auckland and Sydney cohorts, but this may reflect an increase in recognition of OSA in obese children and therefore referrals to the sleep service from general paediatricians and primary care.

Of the patients in the Wellington cohort, over a third had undergone at least one type of ENT intervention prior to referral for CPAP. Although adenotonsillectomy can be helpful for obese children and youth with OSA, some patients continue to have ongoing symptoms requiring further treatment.[[15]] In our group, because of the severity of their OSA, 18 obese patients were referred for CPAP without prior ENT surgery. Of these, seven went on to have ENT surgery at a later date. The other patients referred for CPAP without prior ENT surgery had craniofacial anomalies or other co-morbidities like muscle disorders. We documented ENT surgery events but do not know the number of patients who were assessed by ENT, and where surgery was not recommended.

The use of CPAP to reverse OSA was first reported by Sullivan et al, who documented use in five patients including one 13-year-old.[[16]] This adolescent had been thought to have an intellectual disability however a large part of his learning disability was related to his inability to stay awake at school. This group in Sydney, Australia further expanded the use of CPAP in children reporting in 1995 on the use of nasal CPAP for OSA in 80 children (average age 5.7 years).[[17]] In a report from the USA published the same year documenting use of CPAP in 94 patients, 29% were 1–5 years of age, 36% 6–12 years of age and 32% 13–19 years of age. In the current study, corresponding values were 16%, 32% and 43%, respectively, although the older group did include a few patients >19 years of age. Just over half the patients commenced on CPAP in the current cohort were adolescents (aged ≥10).

This shift to a relatively older age at CPAP initiation may be related to the increase in use of CPAP in obese adolescents. The large age range of patients started on CPAP, particularly those treated past the age of 16, also highlights the need for continuation of care for youth with developmental delay such as patients with Down syndrome. For young people referred approaching the age of cut off for transfer to adult services, it is in the best interests of the patient to commence CPAP in the paediatric sleep service as waiting lists are long in adult sleep services, and services are less flexible in regard to managing adolescents with complex co-morbidities that include intellectual disability. The younger patients treated in the first year of life were infants with OSA related to micrognathia or early tonsillar hypertrophy. For those with isolated micrognathia, symptoms resolved as the jaw grew forward, and so for this group of patients CPAP treatment was not long-term.

With regard to ethnicity, Pacific patients were over-represented in the Wellington group. The average BMI was also higher for Māori and Pacific patients. Māori patients appeared less likely to be compliant with treatment than NZ European and Pacific patients, although this was not tested statistically because of the small numbers in the study, and possible cofounding by other factors such as patient age and reason for treatment. Both Māori and Pacific patients were more likely to live in a more deprived neighbourhood, so these were not differentiating factors. A previous local study assessed CPAP adherence in adult Māori and non-Māori, and found that the poorer adherence demonstrated by Māori was explained, in part, by lower education levels and socio-economic status.[[18]] However, the differences in adherence in that study, while statistically significant, were not very clinically significant. We suspect that in our group, a factor is our failure to consistently provide culturally appropriate services.

Factors such as access to equipment, damage to equipment, social issues, co-morbidities and tolerance to CPAP equipment can impact compliance.[[19,20]] When patients have an intellectual disability or are very young it can be hard for them to describe side effects, especially issues with mask fit. Only around a third of the patients in the current study demonstrated good or usually good compliance. Nixon et al reported on patterns of CPAP adherence during the first three months of treatment in 30 children prescribed CPAP at the Melbourne Children’s Sleep Centre between 2004 and 2008.[[21]] Similar to our report, just 33% met the standard definition of four or more hours use on 70% of nights. Usage in the first week of treatment predicted longer term use over 2–3 months. Hours of use were not affected by age, sex, baseline obstructive apnoea hypopnoea index, or socio-economic status.

Simon et al assessed barriers to CPAP use in a group of American CPAP users aged between 8 and 17 years.[[22]] The average use was 3.35 hours per night and 5 hours per night when only nights of CPAP use were included in the calculation. In this study, 43.1% of youth reported that they just wanted to forget about OSA, and 29.4% reported they were embarrassed to use CPAP. In our local clinical group, we have noted difficulties with machines not being taken when patients go to stay with other family members, or if taken; left behind when the child returns to home base. This suggests that they have not fully accepted the importance of the CPAP treatment. Caregivers may also be embarrassed to report issues with masks, tubing and machines especially if they think they may be responsible for paying for replacement parts.

The addition of a respiratory therapist to CPAP follow-up clinics has been shown to improve compliance for those patients where compliance is <50%.[[23]] Roles can include evaluating the CPAP machine including: masks and tubing; verifying correct CPAP settings; reviewing mask fit; educating parents and patients about the machine including care of the machine; and viewing downloads of treatment. In the Aoteraroa New Zealand setting, these tasks are more likely to be undertaken by a specialist respiratory nurse or a sleep physiologist. At CCDHB, a specialist respiratory nurse has assisted with management of CPAP patients since mid-2017 and we feel this is likely to have contributed to the improvement in compliance in the 2015–2020 period (25% versus 46% for those using CPAP for longer than one month). However, we also had more failed trials in the later period. We have also found it very helpful to have input from whānau care services in the DHB working with Māori whānau in the home setting. Starting a child on CPAP can be a big step for a family, and acclimatisation can require time and patience from both clinicians and whānau. Most of our discharges due to poor compliance or tolerance were in adolescents who had not found that CPAP treatment was sufficiently efficacious for them to persist with daily compliance with treatment.

In summary, this review of children and youth offered or commenced on CPAP through the CCDHB paediatric sleep service over the last 15 years highlights the need for increased availability of services for these high-risk patients. While we have greatly increased our ability to provide an assessment and treatment service for infants and children with persistent symptoms of OSA, we still have quite a way to go to ensure we support our patients to achieve optimal treatment adherence, especially with regard to our young Māori patients. To make improvements in this area we need to ensure we work with culturally appropriate support services, both in the hospital and the community. A qualitative research approach would be valuable to try to understand differences in compliance rates by both age and ethnicity. Services also need to be free for all. We have noted that the need to start paying for consumable equipment can be a barrier to transition to adult services. As we observe the tsunami of referrals for adults requiring treatment of OSA by CPAP, we also need to ensure there is optimal service provision for children and youth with significant OSA. Given the risks to children and youth of suboptimal developmental progress when OSA is untreated, and lifetime increased risks of hypertension and associated cardiovascular morbidity, this area of clinical need must be given greater priority.

Summary

Abstract

Aim

To document the establishment of a Paediatric Continuous Positive Airway Pressure (CPAP) service within the Wellington Region, and review outcomes over the last 15 years.

Method

A retrospective audit of the Paediatric Sleep Service records including clinic letters and polysomnography (PSG) studies for all paediatric patients commenced on CPAP treatment, or for whom CPAP treatment was offered, from November 2005 to December 2020. Data were collected on demographics, medical diagnoses, indications for respiratory support, ENT involvement and surgery. Factors related to CPAP use were also recorded.

Results

Seventy-four children were offered CPAP in the time frame, 52 (70%) male. The age range at onset of CPAP treatment was <1 year of age to 23 years with 12 cases ≥16 years of age. There were 3 (4%) cases presenting before 2006, 11 (15%) cases from 2006–2010, 16 (22%) cases from 2011–2015 and 44 (59%) cases between 2016–2020. Ethnicities included were, 32 (43%) NZ European, 18 (24%) Māori, 19 (26%) Pacific and 5 (7%) Indian/Asian. The most common primary diagnoses were Obesity 21 (28%), Down Syndrome 10 (14%) and Craniofacial abnormalities 8 (11%). One family declined a CPAP trial and there were eight failed CPAP trials. For the remaining 65 patients, compliance with treatment was good/usually good for 25, variable for 19, and poor for 21. Māori patients were less likely to have good/usually good compliance than NZ European and Pacific patients (25% versus 44% and 47% respectively).

Conclusion

Referrals for CPAP treatment in the paediatric age range are increasing and obesity is the commonest co-morbidity. Services need to be culturally appropriate to ensure the best outcomes.

Author Information

Professor Dawn Elder: Professor and HOD, Department of Paediatrics and Child Health, University of Otago, Wellington, Child Health Services, Capital and Coast DHB. Dr Sophie Gandhi: Medical Student (at time study undertaken), Otago Medical School. Associate Professor Angela Campbell: Manager, WellSleep, Department of Medicine, University of Otago Wellington.

Acknowledgements

Sophie Gandhi gathered these data and undertook initial analysis as part of an elective period in her Trainee Intern year at Otago Medical School. Thanks to Tricia Martin, Respiratory Nurse, and the WellSleep sleep physiology team for their significant contributions to the clinical management of these patients.

Correspondence

Prof. Dawn Elder: HOD, Department of Paediatrics and Child Health, University of Otago, Wellington. 0212796140.

Correspondence Email

dawn.elder@otago.ac.nz

Competing Interests

WellSleep has a contract to provide sleep assessment and treatments services for all age groups for CCDHB, HVDHB and WrDHB. Professor Dawn Elder receives remuneration to supervise and report sleep studies undertaken in children and youth at WellSleep.

1) Marcus CL, Brooks LJ, Draper KA, et al. Diagnosis and management of childhood obstructive sleep apnea syndrome. Pediatrics. 2012;130:576-84.

2) Bonuck KA, Chervin RD, Cole TJ et al Prevalence and persistence of sleep disordered breathing symptoms in young children: a 6-year population-based cohort study. Sleep. 2011;34:875-884.

3) Arens R, Marcus CL. Pathophysiology of upper airway obstruction: a developmental perspective. Sleep. 2004; 27:997-1019.

4) Edwards EA, Hsaio K, Nixon GM. Paediatric home ventilatory support: the Auckland experience. J Paediatr Child Health. 2005;41(12):652-8.

5) Luo R, Schoughency E, Gill AI et al. Natural history of snoring and other sleep-disordered breathing (SDB) symptoms in 7-year-old New Zealand children: a follow-up from age 3. Sleep Breath. 2015;19:977-985.

6) Beebe DW. Neurobehavioral morbidity associated with disordered breathing during sleep in children: a comprehensive review. Sleep. 2006;29:1115–34.

7) Baldassari CM, Mitchell RB, Schubert C, Rudnick EF. Pediatric obstructive sleep apnoea and quality of life: A meta-analysis. Otolaryngol Head Neck Surg. 2008;138:265-273.

8) Taumann R, Gulliver TW, Krishna J et al Persistence of obstructive sleep apnea syndrome in children after adenotonsillectomy. J Pediatr. 2006; 149:803-8.

9) Marcus CL, Moore RH, Rosen CL et al. A Randomized trial of adenotonsillectomy for childhood sleep apnea. New Engl J Med 2013;368:2366-76.

10) Edwards EA, Nixon GM on behalf of the Australasian Paediatric Respiratory Group Working Party on Home Ventilation. Paediatric home ventilatory support: changing milieu, proactive solutions. J Paediatr Child Health. 2013;49:13-18.

11) Atkinson J, Salmond C, Crampton P. 2014. NZDep2013 Index of Deprivation. Wellington: Department of Public Health, University of Otago, Wellington. Available online: http://www.otago.ac.nz/wellington/research/hirp/otago020194.html

12) Atkinson J, Salmond C, Crampton P. 2019. NZDep2018 Index of Deprivation. Interim Research Report, December 2019. Wellington: Department of Public Health, University of Otago, Wellington. URL: https://www.otago.ac.nz/wellington/otago730394.pdf

13) Duncanson M, Oben G, Adams J, Richardson G, Wicken A. and Pierson M. 2019. Health and wellbeing of under-15 year olds in Hutt Valley, Capital & Coast and Wairarapa 2018. Dunedin: New Zealand Child and Youth Epidemiology Service, University of Otago. https://www.otago.ac.nz/nzcyes

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16) Sullivan CE, Berthon-Jones M, Issa FQ, Eves L. Reversal of obstructive sleep apnoea by continuous positive airway pressure applied through the nares. Lancet. 1981;1:862-5.

17) Waters KA, Everett FM, Bruderer JW, Sullivan CE. Obstructive sleep apnea: the use of CPAP in 80 children. Am J Respir Crit Care Med. 1995;1562:780-5.

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Obstructive sleep apnoea (OSA) is characterised by repetitive episodes of upper airway obstruction during sleep leading to hypoxia and sleep fragmentation. Prevalence rates in the paediatric population vary between 1.2% to 5.7%.[[1]] When symptoms of apnoea are recorded separately from snoring, snoring is more common (1%–2% versus 3.6%–7.7% for always snoring and 9.6% to 21.2% for habitual snoring).[[2]] Both complete obstruction (apnoea) and partial obstruction (hypopnoea) are associated with oxygen desaturation and arousal in children. The commonest cause is adenotonsillar hypertrophy, but obesity is increasingly being associated with OSA in later childhood and adolescence. Other risk factors include craniofacial anomalies, neuromuscular disorders, congenital/chromosomal syndromes (most commonly trisomy 21) and central nervous system disorders.[[3,4]]

The prevalence of OSA in the child and youth population of Aotearoa New Zealand is not known. In a community sample of 839 3-year-old children, of whom around half were followed up at 7 years of age, prevalence of habitual snoring was similar at the two time points (11.3% versus 9.2%) but there were individual changes in status over time, highlighting the need for regular screening for symptoms including after adenotonsillectomy.[[5]] Untreated OSA has been associated with impairments in memory and attention, learning deficits and difficult behaviour and so attention to treatment is important.[[6]] Obstructive sleep apnoea can lead to daytime sleepiness and hyperactive behaviour. At night, sleep is restless and waking common with consequent secondary effects on caregivers including sleep disturbance, fatigue and mood changes.

The first line of treatment in children, adenotonsillectomy, improves quality of life but may not resolve all symptoms in all children.[[7–9]] Those with predisposing factors such as obesity, craniofacial anomalies and neuromuscular or other congenital syndromes may require alternative treatments such as continuous positive airway pressure (CPAP).

Paediatric sleep services are well established in the main centres in Australia. Currently in Aotearoa New Zealand, only Wellington and Auckland have established services for paediatric sleep studies reported by a paediatric sleep physician, although a developing specialist service is now available in Christchurch with the recent arrival of a paediatric specialist trained in sleep medicine. In 2005, colleagues at Starship hospital Auckland reported on non-invasive ventilation use in the paediatric population in New Zealand including 47 patients on CPAP.[[4]] A trend was noted then of increasing numbers of children receiving respiratory support at home. In 2013, the Australasian Paediatric Respiratory Group reported data on paediatric home ventilatory support across Australasia, providing estimates of numbers using CPAP and expressing concern about data quality and equity of access to services.[[10]]

The collaboration between Capital and Coast DHB (CCDHB) and the University of Otago WellSleep adult sleep laboratory started in 1997. Initially, with regard to the paediatric age range, there was more emphasis on neonatal polysomnography (PSG) and research in infant breathing. Paediatric sleep clinics commenced at CCDHB in 2005 and were led by a qualified paediatric sleep physician from 2008. Since then, a growing number of children have been seen, assessed and offered CPAP therapy. This review aimed to determine the effectiveness of the establishment of CPAP treatment in children within the Wellington Region, and to see if there had been improvements over the last 15 years. We also examined the reasons for CPAP treatment and associated demographic factors.

Method

This was a retrospective review of paediatric sleep service records at CCDHB including clinic letters and PSG studies to identify all children offered CPAP treatment from November 2005 to December 2020. CCDHB contracts paediatric sleep assessment services also for Hutt Valley and Wairarapa DHBs from the WellSleep sleep laboratory at the University of Otago, Wellington. Data were collected on demographics, medical diagnoses, indications for respiratory support, Ear Nose and Throat (ENT) specialist involvement and surgery. The NZ Deprivation Index was calculated from NZDep2013 or NZDep2018 data depending on when the patient was first seen.[[11,12]] A BMI at or above the 95th percentile for age and gender was considered overweight. Factors related to CPAP use were also recorded including the year first seen by the service, number of PSG studies undertaken and initial apnoea hypopnea index (AHI).

Compliance was assessed from clinical information rather than machine downloads, as the availability of these changed over the review period. Compliance was documented as either “usually good” (patient using CPAP for >4 hours each night for >70% of the week), “good” (patient using CPAP 50% of the week), “variable” (intermittent use of CPAP) or “poor” (patient never established on CPAP). A “failed trial” was recorded if the patient had not completed the initial one-month CPAP trial. A “declined trial” was recorded if the family did not take up the offer of CPAP treatment. Patient characteristics and compliance were compared between two time periods, 2005–2014 and 2015–2020. Data were collated into a Microsoft Excel database, and summary statistics generated using Excel functions. The audit was approved by the Child Health Service governance group at CCDHB.

Results

Seventy-four patients were offered CPAP therapy over the time period, of whom 52 (70%) were male. Age at commencement varied between less than one year of age to 23 years of age, the latter being a Down syndrome patient. Patients were offered CPAP across the child and youth age range with 12 cases being ≥16 years of age. (Figure 1). Patient demographics are shown in Table 1. NZ European cases were under-represented and Pacific and Other ethnicities over-represented.

View Table 1.

Figure 1: Age at which CPAP was first offered or commenced.

The Deprivation Index quintile for cases is illustrated in Table 1. Although all quintiles were represented, the highest number of cases were from Quintile 5. This is not representative of data for the <15-year age group from Capital and Coast, Hutt Valley and Wairarapa district health boards (DHBs), where Quintile 4 is the predominant quintile for Hutt Valley and Wairarapa and Quintile 1 for Capital and Coast DHB.[[13]] Forty-five (61%) patients were from Capital and Coast DHB, 24 (33%) from Hutt Valley DHB, three (4%) from Wairarapa DHB and one (1%) each from Whanganui and Nelson Marlborough DHBs.

Patients were initiated on CPAP therapy every year from 2005 to 2020. Early on in the time period, two Wellington patients were started on CPAP at Auckland Starship hospital. Three other patients commenced CPAP elsewhere and then transferred to Wellington because of a change in personal circumstances. There was a marked increase in numbers of patients offered CPAP treatment over the audit period (Figure 2).

The mean Body Mass Index (BMI) when offered CPAP therapy was 30.6 kg/m[[ 2]] (SD 11.9), ranging from 13.1kg/m2 to 68.6kg/m2. BMI was unavailable for three patients. There were 40 (54%) patients with a BMI >95th centile for age. The mean BMI was higher for Māori and Pacific patients than for NZ European patients (Table 1). Obesity was the most commonly documented co-morbidity contributing to the need for CPAP treatment followed by Down syndrome and craniofacial anomalies (Table 2).

Figure 2: Year CPAP offered or commenced.

The most common sleep diagnosis resulting in offering CPAP was OSA (69 (82%) patients). Three patients had a mixed picture of central and obstructive apnoea on PSG, and one patient had evidence of OSA with a degree of hypoventilation. A further patient had catathrenia without significant OSA on overnight PSG. Diagnostic PSG was unavailable for five (18%) patients. For the remainder, six had an apnoea hypopnoea index (AHI) between 1–5 events per hour, 13 had an AHI between 5–9 events per hour, and 11 had an AHI between 0–14 events per hour. The remaining 39 patients had an AHI ≥15 events per hour with four having an AHI >90 events per hour. Some patients had a full night diagnostic study, and some had a split study with a shorter diagnostic period and CPAP applied during the night of the initial study, which would explain some variation in the initial AHI.

Twenty-nine (39%) patients had at least one type of ENT procedure prior to CPAP treatment. The most common procedure was adenotonsillectomy (n=20) followed by other nasal surgery (n=7), adenotonsillectomy plus revision adenoidectomy (n=4), tonsillectomy alone (n=3) and adenoidectomy alone (n=1). Seven patients had two procedures and three patients had three procedures. There were also a number of patients who had ENT procedures after being offered CPAP. These procedures included adenotonsillectomy (n=9), other nasal surgery (n=6), tonsillectomy (n=5), revision adenoidectomy (n=3) and lingual tonsillectomy (n=1).

With regard to acceptance of treatment, one family declined the offer of CPAP treatment, and eight patients did not complete the initial trial period. The eight patients not completing the CPAP trial were all ≥10 years of age as was the patient for whom a CPAP trial was declined. Compliance data are shown in Table 3.

When age was considered for patients using CPAP beyond a month, the best compliance was seen in the 0–4 year age group. When ethnicity was considered, Māori patients appeared less likely to have good or usually good compliance. For those patients who completed the one-month trial, good/usually good compliance was more commonly documented in the second time period.

During CPAP treatment, overnight PSG recordings were undertaken for monitoring pressure requirements over time. The average number of studies per patient, including the initial diagnostic study, was 2.5 studies (median 2, range 1–11). Younger children continuing CPAP over a longer period of time had studies undertaken every one to two years to review pressure requirements.

By the end of 2020, 54 patients were discharged from the service or stopped using CPAP and 20 patients remained current patients. Reasons for discharge are shown in Table 4. The most common reasons for discharge were poor tolerance and compliance (n=13) and transfer to adult sleep services (n=12). Nine patients demonstrated an improvement in OSA symptoms after ENT surgery and six improved for other reasons. Some of these were infants who demonstrated improvement in micrognathia during the first year of life.

View Tables 2–4.

Discussion

This review of patients managed through the paediatric sleep service at CCDHB indicates the wide range of ages and underlying diagnoses of children presenting with OSA and requiring treatment with CPAP. Also, just as there has been an explosion of CPAP use for adult patients in recent years, so also in the infant, child and youth age range an increasing number of patients are being treated with CPAP. These cases are likely just the tip of the iceberg in regard to the numbers who would benefit from this treatment. The increased referrals suggest greater recognition by a range of clinicians that CPAP may be a useful treatment for these patients.

The most common indication for CPAP commencement was, as expected, OSA and the most common primary clinical associations were obesity (without other co-morbid factors), Down syndrome and craniofacial abnormalities. Children with neurological disorders compromising upper airway function during sleep are also increasingly being referred for consideration of CPAP. These findings are similar in some respects to the Starship hospital study reporting on 108 children started on CPAP between 1999 to 2004.[[4]] The most common indication for respiratory support in the Auckland cohort was respiratory airway disease followed by neuromuscular disease and central nervous system disorder. Obesity was “not a common indication”. Machalaani et al. reported in 2016 on the effectiveness of CPAP in 55 children 0–18 years of age from the Children’s Hospital at Westmead in Sydney.[[14]] Just under 90% of CPAP users were in diagnostic categories grouped as chromosomal, neuromuscular, lung disorder, central nervous system disorder or “other” disorder. Only five CPAP users were documented as being obese.

In contrast, just over half the patients in the current study had a BMI >95th centile. For 29% of the group, obesity was the main reason for the OSA whereas for others the obesity was a co-morbidity in association with diagnoses such as Prader–Willi syndrome, Down syndrome and Duchenne muscular dystrophy. The current data therefore suggest that although CPAP is being used for patients with a wide variety of diagnoses as previously documented, its use is increasing in children and youth with obesity without other clinical co-morbidities. It is not clear why the current data are different from Auckland and Sydney cohorts, but this may reflect an increase in recognition of OSA in obese children and therefore referrals to the sleep service from general paediatricians and primary care.

Of the patients in the Wellington cohort, over a third had undergone at least one type of ENT intervention prior to referral for CPAP. Although adenotonsillectomy can be helpful for obese children and youth with OSA, some patients continue to have ongoing symptoms requiring further treatment.[[15]] In our group, because of the severity of their OSA, 18 obese patients were referred for CPAP without prior ENT surgery. Of these, seven went on to have ENT surgery at a later date. The other patients referred for CPAP without prior ENT surgery had craniofacial anomalies or other co-morbidities like muscle disorders. We documented ENT surgery events but do not know the number of patients who were assessed by ENT, and where surgery was not recommended.

The use of CPAP to reverse OSA was first reported by Sullivan et al, who documented use in five patients including one 13-year-old.[[16]] This adolescent had been thought to have an intellectual disability however a large part of his learning disability was related to his inability to stay awake at school. This group in Sydney, Australia further expanded the use of CPAP in children reporting in 1995 on the use of nasal CPAP for OSA in 80 children (average age 5.7 years).[[17]] In a report from the USA published the same year documenting use of CPAP in 94 patients, 29% were 1–5 years of age, 36% 6–12 years of age and 32% 13–19 years of age. In the current study, corresponding values were 16%, 32% and 43%, respectively, although the older group did include a few patients >19 years of age. Just over half the patients commenced on CPAP in the current cohort were adolescents (aged ≥10).

This shift to a relatively older age at CPAP initiation may be related to the increase in use of CPAP in obese adolescents. The large age range of patients started on CPAP, particularly those treated past the age of 16, also highlights the need for continuation of care for youth with developmental delay such as patients with Down syndrome. For young people referred approaching the age of cut off for transfer to adult services, it is in the best interests of the patient to commence CPAP in the paediatric sleep service as waiting lists are long in adult sleep services, and services are less flexible in regard to managing adolescents with complex co-morbidities that include intellectual disability. The younger patients treated in the first year of life were infants with OSA related to micrognathia or early tonsillar hypertrophy. For those with isolated micrognathia, symptoms resolved as the jaw grew forward, and so for this group of patients CPAP treatment was not long-term.

With regard to ethnicity, Pacific patients were over-represented in the Wellington group. The average BMI was also higher for Māori and Pacific patients. Māori patients appeared less likely to be compliant with treatment than NZ European and Pacific patients, although this was not tested statistically because of the small numbers in the study, and possible cofounding by other factors such as patient age and reason for treatment. Both Māori and Pacific patients were more likely to live in a more deprived neighbourhood, so these were not differentiating factors. A previous local study assessed CPAP adherence in adult Māori and non-Māori, and found that the poorer adherence demonstrated by Māori was explained, in part, by lower education levels and socio-economic status.[[18]] However, the differences in adherence in that study, while statistically significant, were not very clinically significant. We suspect that in our group, a factor is our failure to consistently provide culturally appropriate services.

Factors such as access to equipment, damage to equipment, social issues, co-morbidities and tolerance to CPAP equipment can impact compliance.[[19,20]] When patients have an intellectual disability or are very young it can be hard for them to describe side effects, especially issues with mask fit. Only around a third of the patients in the current study demonstrated good or usually good compliance. Nixon et al reported on patterns of CPAP adherence during the first three months of treatment in 30 children prescribed CPAP at the Melbourne Children’s Sleep Centre between 2004 and 2008.[[21]] Similar to our report, just 33% met the standard definition of four or more hours use on 70% of nights. Usage in the first week of treatment predicted longer term use over 2–3 months. Hours of use were not affected by age, sex, baseline obstructive apnoea hypopnoea index, or socio-economic status.

Simon et al assessed barriers to CPAP use in a group of American CPAP users aged between 8 and 17 years.[[22]] The average use was 3.35 hours per night and 5 hours per night when only nights of CPAP use were included in the calculation. In this study, 43.1% of youth reported that they just wanted to forget about OSA, and 29.4% reported they were embarrassed to use CPAP. In our local clinical group, we have noted difficulties with machines not being taken when patients go to stay with other family members, or if taken; left behind when the child returns to home base. This suggests that they have not fully accepted the importance of the CPAP treatment. Caregivers may also be embarrassed to report issues with masks, tubing and machines especially if they think they may be responsible for paying for replacement parts.

The addition of a respiratory therapist to CPAP follow-up clinics has been shown to improve compliance for those patients where compliance is <50%.[[23]] Roles can include evaluating the CPAP machine including: masks and tubing; verifying correct CPAP settings; reviewing mask fit; educating parents and patients about the machine including care of the machine; and viewing downloads of treatment. In the Aoteraroa New Zealand setting, these tasks are more likely to be undertaken by a specialist respiratory nurse or a sleep physiologist. At CCDHB, a specialist respiratory nurse has assisted with management of CPAP patients since mid-2017 and we feel this is likely to have contributed to the improvement in compliance in the 2015–2020 period (25% versus 46% for those using CPAP for longer than one month). However, we also had more failed trials in the later period. We have also found it very helpful to have input from whānau care services in the DHB working with Māori whānau in the home setting. Starting a child on CPAP can be a big step for a family, and acclimatisation can require time and patience from both clinicians and whānau. Most of our discharges due to poor compliance or tolerance were in adolescents who had not found that CPAP treatment was sufficiently efficacious for them to persist with daily compliance with treatment.

In summary, this review of children and youth offered or commenced on CPAP through the CCDHB paediatric sleep service over the last 15 years highlights the need for increased availability of services for these high-risk patients. While we have greatly increased our ability to provide an assessment and treatment service for infants and children with persistent symptoms of OSA, we still have quite a way to go to ensure we support our patients to achieve optimal treatment adherence, especially with regard to our young Māori patients. To make improvements in this area we need to ensure we work with culturally appropriate support services, both in the hospital and the community. A qualitative research approach would be valuable to try to understand differences in compliance rates by both age and ethnicity. Services also need to be free for all. We have noted that the need to start paying for consumable equipment can be a barrier to transition to adult services. As we observe the tsunami of referrals for adults requiring treatment of OSA by CPAP, we also need to ensure there is optimal service provision for children and youth with significant OSA. Given the risks to children and youth of suboptimal developmental progress when OSA is untreated, and lifetime increased risks of hypertension and associated cardiovascular morbidity, this area of clinical need must be given greater priority.

Summary

Abstract

Aim

To document the establishment of a Paediatric Continuous Positive Airway Pressure (CPAP) service within the Wellington Region, and review outcomes over the last 15 years.

Method

A retrospective audit of the Paediatric Sleep Service records including clinic letters and polysomnography (PSG) studies for all paediatric patients commenced on CPAP treatment, or for whom CPAP treatment was offered, from November 2005 to December 2020. Data were collected on demographics, medical diagnoses, indications for respiratory support, ENT involvement and surgery. Factors related to CPAP use were also recorded.

Results

Seventy-four children were offered CPAP in the time frame, 52 (70%) male. The age range at onset of CPAP treatment was <1 year of age to 23 years with 12 cases ≥16 years of age. There were 3 (4%) cases presenting before 2006, 11 (15%) cases from 2006–2010, 16 (22%) cases from 2011–2015 and 44 (59%) cases between 2016–2020. Ethnicities included were, 32 (43%) NZ European, 18 (24%) Māori, 19 (26%) Pacific and 5 (7%) Indian/Asian. The most common primary diagnoses were Obesity 21 (28%), Down Syndrome 10 (14%) and Craniofacial abnormalities 8 (11%). One family declined a CPAP trial and there were eight failed CPAP trials. For the remaining 65 patients, compliance with treatment was good/usually good for 25, variable for 19, and poor for 21. Māori patients were less likely to have good/usually good compliance than NZ European and Pacific patients (25% versus 44% and 47% respectively).

Conclusion

Referrals for CPAP treatment in the paediatric age range are increasing and obesity is the commonest co-morbidity. Services need to be culturally appropriate to ensure the best outcomes.

Author Information

Professor Dawn Elder: Professor and HOD, Department of Paediatrics and Child Health, University of Otago, Wellington, Child Health Services, Capital and Coast DHB. Dr Sophie Gandhi: Medical Student (at time study undertaken), Otago Medical School. Associate Professor Angela Campbell: Manager, WellSleep, Department of Medicine, University of Otago Wellington.

Acknowledgements

Sophie Gandhi gathered these data and undertook initial analysis as part of an elective period in her Trainee Intern year at Otago Medical School. Thanks to Tricia Martin, Respiratory Nurse, and the WellSleep sleep physiology team for their significant contributions to the clinical management of these patients.

Correspondence

Prof. Dawn Elder: HOD, Department of Paediatrics and Child Health, University of Otago, Wellington. 0212796140.

Correspondence Email

dawn.elder@otago.ac.nz

Competing Interests

WellSleep has a contract to provide sleep assessment and treatments services for all age groups for CCDHB, HVDHB and WrDHB. Professor Dawn Elder receives remuneration to supervise and report sleep studies undertaken in children and youth at WellSleep.

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2) Bonuck KA, Chervin RD, Cole TJ et al Prevalence and persistence of sleep disordered breathing symptoms in young children: a 6-year population-based cohort study. Sleep. 2011;34:875-884.

3) Arens R, Marcus CL. Pathophysiology of upper airway obstruction: a developmental perspective. Sleep. 2004; 27:997-1019.

4) Edwards EA, Hsaio K, Nixon GM. Paediatric home ventilatory support: the Auckland experience. J Paediatr Child Health. 2005;41(12):652-8.

5) Luo R, Schoughency E, Gill AI et al. Natural history of snoring and other sleep-disordered breathing (SDB) symptoms in 7-year-old New Zealand children: a follow-up from age 3. Sleep Breath. 2015;19:977-985.

6) Beebe DW. Neurobehavioral morbidity associated with disordered breathing during sleep in children: a comprehensive review. Sleep. 2006;29:1115–34.

7) Baldassari CM, Mitchell RB, Schubert C, Rudnick EF. Pediatric obstructive sleep apnoea and quality of life: A meta-analysis. Otolaryngol Head Neck Surg. 2008;138:265-273.

8) Taumann R, Gulliver TW, Krishna J et al Persistence of obstructive sleep apnea syndrome in children after adenotonsillectomy. J Pediatr. 2006; 149:803-8.

9) Marcus CL, Moore RH, Rosen CL et al. A Randomized trial of adenotonsillectomy for childhood sleep apnea. New Engl J Med 2013;368:2366-76.

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11) Atkinson J, Salmond C, Crampton P. 2014. NZDep2013 Index of Deprivation. Wellington: Department of Public Health, University of Otago, Wellington. Available online: http://www.otago.ac.nz/wellington/research/hirp/otago020194.html

12) Atkinson J, Salmond C, Crampton P. 2019. NZDep2018 Index of Deprivation. Interim Research Report, December 2019. Wellington: Department of Public Health, University of Otago, Wellington. URL: https://www.otago.ac.nz/wellington/otago730394.pdf

13) Duncanson M, Oben G, Adams J, Richardson G, Wicken A. and Pierson M. 2019. Health and wellbeing of under-15 year olds in Hutt Valley, Capital & Coast and Wairarapa 2018. Dunedin: New Zealand Child and Youth Epidemiology Service, University of Otago. https://www.otago.ac.nz/nzcyes

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Obstructive sleep apnoea (OSA) is characterised by repetitive episodes of upper airway obstruction during sleep leading to hypoxia and sleep fragmentation. Prevalence rates in the paediatric population vary between 1.2% to 5.7%.[[1]] When symptoms of apnoea are recorded separately from snoring, snoring is more common (1%–2% versus 3.6%–7.7% for always snoring and 9.6% to 21.2% for habitual snoring).[[2]] Both complete obstruction (apnoea) and partial obstruction (hypopnoea) are associated with oxygen desaturation and arousal in children. The commonest cause is adenotonsillar hypertrophy, but obesity is increasingly being associated with OSA in later childhood and adolescence. Other risk factors include craniofacial anomalies, neuromuscular disorders, congenital/chromosomal syndromes (most commonly trisomy 21) and central nervous system disorders.[[3,4]]

The prevalence of OSA in the child and youth population of Aotearoa New Zealand is not known. In a community sample of 839 3-year-old children, of whom around half were followed up at 7 years of age, prevalence of habitual snoring was similar at the two time points (11.3% versus 9.2%) but there were individual changes in status over time, highlighting the need for regular screening for symptoms including after adenotonsillectomy.[[5]] Untreated OSA has been associated with impairments in memory and attention, learning deficits and difficult behaviour and so attention to treatment is important.[[6]] Obstructive sleep apnoea can lead to daytime sleepiness and hyperactive behaviour. At night, sleep is restless and waking common with consequent secondary effects on caregivers including sleep disturbance, fatigue and mood changes.

The first line of treatment in children, adenotonsillectomy, improves quality of life but may not resolve all symptoms in all children.[[7–9]] Those with predisposing factors such as obesity, craniofacial anomalies and neuromuscular or other congenital syndromes may require alternative treatments such as continuous positive airway pressure (CPAP).

Paediatric sleep services are well established in the main centres in Australia. Currently in Aotearoa New Zealand, only Wellington and Auckland have established services for paediatric sleep studies reported by a paediatric sleep physician, although a developing specialist service is now available in Christchurch with the recent arrival of a paediatric specialist trained in sleep medicine. In 2005, colleagues at Starship hospital Auckland reported on non-invasive ventilation use in the paediatric population in New Zealand including 47 patients on CPAP.[[4]] A trend was noted then of increasing numbers of children receiving respiratory support at home. In 2013, the Australasian Paediatric Respiratory Group reported data on paediatric home ventilatory support across Australasia, providing estimates of numbers using CPAP and expressing concern about data quality and equity of access to services.[[10]]

The collaboration between Capital and Coast DHB (CCDHB) and the University of Otago WellSleep adult sleep laboratory started in 1997. Initially, with regard to the paediatric age range, there was more emphasis on neonatal polysomnography (PSG) and research in infant breathing. Paediatric sleep clinics commenced at CCDHB in 2005 and were led by a qualified paediatric sleep physician from 2008. Since then, a growing number of children have been seen, assessed and offered CPAP therapy. This review aimed to determine the effectiveness of the establishment of CPAP treatment in children within the Wellington Region, and to see if there had been improvements over the last 15 years. We also examined the reasons for CPAP treatment and associated demographic factors.

Method

This was a retrospective review of paediatric sleep service records at CCDHB including clinic letters and PSG studies to identify all children offered CPAP treatment from November 2005 to December 2020. CCDHB contracts paediatric sleep assessment services also for Hutt Valley and Wairarapa DHBs from the WellSleep sleep laboratory at the University of Otago, Wellington. Data were collected on demographics, medical diagnoses, indications for respiratory support, Ear Nose and Throat (ENT) specialist involvement and surgery. The NZ Deprivation Index was calculated from NZDep2013 or NZDep2018 data depending on when the patient was first seen.[[11,12]] A BMI at or above the 95th percentile for age and gender was considered overweight. Factors related to CPAP use were also recorded including the year first seen by the service, number of PSG studies undertaken and initial apnoea hypopnea index (AHI).

Compliance was assessed from clinical information rather than machine downloads, as the availability of these changed over the review period. Compliance was documented as either “usually good” (patient using CPAP for >4 hours each night for >70% of the week), “good” (patient using CPAP 50% of the week), “variable” (intermittent use of CPAP) or “poor” (patient never established on CPAP). A “failed trial” was recorded if the patient had not completed the initial one-month CPAP trial. A “declined trial” was recorded if the family did not take up the offer of CPAP treatment. Patient characteristics and compliance were compared between two time periods, 2005–2014 and 2015–2020. Data were collated into a Microsoft Excel database, and summary statistics generated using Excel functions. The audit was approved by the Child Health Service governance group at CCDHB.

Results

Seventy-four patients were offered CPAP therapy over the time period, of whom 52 (70%) were male. Age at commencement varied between less than one year of age to 23 years of age, the latter being a Down syndrome patient. Patients were offered CPAP across the child and youth age range with 12 cases being ≥16 years of age. (Figure 1). Patient demographics are shown in Table 1. NZ European cases were under-represented and Pacific and Other ethnicities over-represented.

View Table 1.

Figure 1: Age at which CPAP was first offered or commenced.

The Deprivation Index quintile for cases is illustrated in Table 1. Although all quintiles were represented, the highest number of cases were from Quintile 5. This is not representative of data for the <15-year age group from Capital and Coast, Hutt Valley and Wairarapa district health boards (DHBs), where Quintile 4 is the predominant quintile for Hutt Valley and Wairarapa and Quintile 1 for Capital and Coast DHB.[[13]] Forty-five (61%) patients were from Capital and Coast DHB, 24 (33%) from Hutt Valley DHB, three (4%) from Wairarapa DHB and one (1%) each from Whanganui and Nelson Marlborough DHBs.

Patients were initiated on CPAP therapy every year from 2005 to 2020. Early on in the time period, two Wellington patients were started on CPAP at Auckland Starship hospital. Three other patients commenced CPAP elsewhere and then transferred to Wellington because of a change in personal circumstances. There was a marked increase in numbers of patients offered CPAP treatment over the audit period (Figure 2).

The mean Body Mass Index (BMI) when offered CPAP therapy was 30.6 kg/m[[ 2]] (SD 11.9), ranging from 13.1kg/m2 to 68.6kg/m2. BMI was unavailable for three patients. There were 40 (54%) patients with a BMI >95th centile for age. The mean BMI was higher for Māori and Pacific patients than for NZ European patients (Table 1). Obesity was the most commonly documented co-morbidity contributing to the need for CPAP treatment followed by Down syndrome and craniofacial anomalies (Table 2).

Figure 2: Year CPAP offered or commenced.

The most common sleep diagnosis resulting in offering CPAP was OSA (69 (82%) patients). Three patients had a mixed picture of central and obstructive apnoea on PSG, and one patient had evidence of OSA with a degree of hypoventilation. A further patient had catathrenia without significant OSA on overnight PSG. Diagnostic PSG was unavailable for five (18%) patients. For the remainder, six had an apnoea hypopnoea index (AHI) between 1–5 events per hour, 13 had an AHI between 5–9 events per hour, and 11 had an AHI between 0–14 events per hour. The remaining 39 patients had an AHI ≥15 events per hour with four having an AHI >90 events per hour. Some patients had a full night diagnostic study, and some had a split study with a shorter diagnostic period and CPAP applied during the night of the initial study, which would explain some variation in the initial AHI.

Twenty-nine (39%) patients had at least one type of ENT procedure prior to CPAP treatment. The most common procedure was adenotonsillectomy (n=20) followed by other nasal surgery (n=7), adenotonsillectomy plus revision adenoidectomy (n=4), tonsillectomy alone (n=3) and adenoidectomy alone (n=1). Seven patients had two procedures and three patients had three procedures. There were also a number of patients who had ENT procedures after being offered CPAP. These procedures included adenotonsillectomy (n=9), other nasal surgery (n=6), tonsillectomy (n=5), revision adenoidectomy (n=3) and lingual tonsillectomy (n=1).

With regard to acceptance of treatment, one family declined the offer of CPAP treatment, and eight patients did not complete the initial trial period. The eight patients not completing the CPAP trial were all ≥10 years of age as was the patient for whom a CPAP trial was declined. Compliance data are shown in Table 3.

When age was considered for patients using CPAP beyond a month, the best compliance was seen in the 0–4 year age group. When ethnicity was considered, Māori patients appeared less likely to have good or usually good compliance. For those patients who completed the one-month trial, good/usually good compliance was more commonly documented in the second time period.

During CPAP treatment, overnight PSG recordings were undertaken for monitoring pressure requirements over time. The average number of studies per patient, including the initial diagnostic study, was 2.5 studies (median 2, range 1–11). Younger children continuing CPAP over a longer period of time had studies undertaken every one to two years to review pressure requirements.

By the end of 2020, 54 patients were discharged from the service or stopped using CPAP and 20 patients remained current patients. Reasons for discharge are shown in Table 4. The most common reasons for discharge were poor tolerance and compliance (n=13) and transfer to adult sleep services (n=12). Nine patients demonstrated an improvement in OSA symptoms after ENT surgery and six improved for other reasons. Some of these were infants who demonstrated improvement in micrognathia during the first year of life.

View Tables 2–4.

Discussion

This review of patients managed through the paediatric sleep service at CCDHB indicates the wide range of ages and underlying diagnoses of children presenting with OSA and requiring treatment with CPAP. Also, just as there has been an explosion of CPAP use for adult patients in recent years, so also in the infant, child and youth age range an increasing number of patients are being treated with CPAP. These cases are likely just the tip of the iceberg in regard to the numbers who would benefit from this treatment. The increased referrals suggest greater recognition by a range of clinicians that CPAP may be a useful treatment for these patients.

The most common indication for CPAP commencement was, as expected, OSA and the most common primary clinical associations were obesity (without other co-morbid factors), Down syndrome and craniofacial abnormalities. Children with neurological disorders compromising upper airway function during sleep are also increasingly being referred for consideration of CPAP. These findings are similar in some respects to the Starship hospital study reporting on 108 children started on CPAP between 1999 to 2004.[[4]] The most common indication for respiratory support in the Auckland cohort was respiratory airway disease followed by neuromuscular disease and central nervous system disorder. Obesity was “not a common indication”. Machalaani et al. reported in 2016 on the effectiveness of CPAP in 55 children 0–18 years of age from the Children’s Hospital at Westmead in Sydney.[[14]] Just under 90% of CPAP users were in diagnostic categories grouped as chromosomal, neuromuscular, lung disorder, central nervous system disorder or “other” disorder. Only five CPAP users were documented as being obese.

In contrast, just over half the patients in the current study had a BMI >95th centile. For 29% of the group, obesity was the main reason for the OSA whereas for others the obesity was a co-morbidity in association with diagnoses such as Prader–Willi syndrome, Down syndrome and Duchenne muscular dystrophy. The current data therefore suggest that although CPAP is being used for patients with a wide variety of diagnoses as previously documented, its use is increasing in children and youth with obesity without other clinical co-morbidities. It is not clear why the current data are different from Auckland and Sydney cohorts, but this may reflect an increase in recognition of OSA in obese children and therefore referrals to the sleep service from general paediatricians and primary care.

Of the patients in the Wellington cohort, over a third had undergone at least one type of ENT intervention prior to referral for CPAP. Although adenotonsillectomy can be helpful for obese children and youth with OSA, some patients continue to have ongoing symptoms requiring further treatment.[[15]] In our group, because of the severity of their OSA, 18 obese patients were referred for CPAP without prior ENT surgery. Of these, seven went on to have ENT surgery at a later date. The other patients referred for CPAP without prior ENT surgery had craniofacial anomalies or other co-morbidities like muscle disorders. We documented ENT surgery events but do not know the number of patients who were assessed by ENT, and where surgery was not recommended.

The use of CPAP to reverse OSA was first reported by Sullivan et al, who documented use in five patients including one 13-year-old.[[16]] This adolescent had been thought to have an intellectual disability however a large part of his learning disability was related to his inability to stay awake at school. This group in Sydney, Australia further expanded the use of CPAP in children reporting in 1995 on the use of nasal CPAP for OSA in 80 children (average age 5.7 years).[[17]] In a report from the USA published the same year documenting use of CPAP in 94 patients, 29% were 1–5 years of age, 36% 6–12 years of age and 32% 13–19 years of age. In the current study, corresponding values were 16%, 32% and 43%, respectively, although the older group did include a few patients >19 years of age. Just over half the patients commenced on CPAP in the current cohort were adolescents (aged ≥10).

This shift to a relatively older age at CPAP initiation may be related to the increase in use of CPAP in obese adolescents. The large age range of patients started on CPAP, particularly those treated past the age of 16, also highlights the need for continuation of care for youth with developmental delay such as patients with Down syndrome. For young people referred approaching the age of cut off for transfer to adult services, it is in the best interests of the patient to commence CPAP in the paediatric sleep service as waiting lists are long in adult sleep services, and services are less flexible in regard to managing adolescents with complex co-morbidities that include intellectual disability. The younger patients treated in the first year of life were infants with OSA related to micrognathia or early tonsillar hypertrophy. For those with isolated micrognathia, symptoms resolved as the jaw grew forward, and so for this group of patients CPAP treatment was not long-term.

With regard to ethnicity, Pacific patients were over-represented in the Wellington group. The average BMI was also higher for Māori and Pacific patients. Māori patients appeared less likely to be compliant with treatment than NZ European and Pacific patients, although this was not tested statistically because of the small numbers in the study, and possible cofounding by other factors such as patient age and reason for treatment. Both Māori and Pacific patients were more likely to live in a more deprived neighbourhood, so these were not differentiating factors. A previous local study assessed CPAP adherence in adult Māori and non-Māori, and found that the poorer adherence demonstrated by Māori was explained, in part, by lower education levels and socio-economic status.[[18]] However, the differences in adherence in that study, while statistically significant, were not very clinically significant. We suspect that in our group, a factor is our failure to consistently provide culturally appropriate services.

Factors such as access to equipment, damage to equipment, social issues, co-morbidities and tolerance to CPAP equipment can impact compliance.[[19,20]] When patients have an intellectual disability or are very young it can be hard for them to describe side effects, especially issues with mask fit. Only around a third of the patients in the current study demonstrated good or usually good compliance. Nixon et al reported on patterns of CPAP adherence during the first three months of treatment in 30 children prescribed CPAP at the Melbourne Children’s Sleep Centre between 2004 and 2008.[[21]] Similar to our report, just 33% met the standard definition of four or more hours use on 70% of nights. Usage in the first week of treatment predicted longer term use over 2–3 months. Hours of use were not affected by age, sex, baseline obstructive apnoea hypopnoea index, or socio-economic status.

Simon et al assessed barriers to CPAP use in a group of American CPAP users aged between 8 and 17 years.[[22]] The average use was 3.35 hours per night and 5 hours per night when only nights of CPAP use were included in the calculation. In this study, 43.1% of youth reported that they just wanted to forget about OSA, and 29.4% reported they were embarrassed to use CPAP. In our local clinical group, we have noted difficulties with machines not being taken when patients go to stay with other family members, or if taken; left behind when the child returns to home base. This suggests that they have not fully accepted the importance of the CPAP treatment. Caregivers may also be embarrassed to report issues with masks, tubing and machines especially if they think they may be responsible for paying for replacement parts.

The addition of a respiratory therapist to CPAP follow-up clinics has been shown to improve compliance for those patients where compliance is <50%.[[23]] Roles can include evaluating the CPAP machine including: masks and tubing; verifying correct CPAP settings; reviewing mask fit; educating parents and patients about the machine including care of the machine; and viewing downloads of treatment. In the Aoteraroa New Zealand setting, these tasks are more likely to be undertaken by a specialist respiratory nurse or a sleep physiologist. At CCDHB, a specialist respiratory nurse has assisted with management of CPAP patients since mid-2017 and we feel this is likely to have contributed to the improvement in compliance in the 2015–2020 period (25% versus 46% for those using CPAP for longer than one month). However, we also had more failed trials in the later period. We have also found it very helpful to have input from whānau care services in the DHB working with Māori whānau in the home setting. Starting a child on CPAP can be a big step for a family, and acclimatisation can require time and patience from both clinicians and whānau. Most of our discharges due to poor compliance or tolerance were in adolescents who had not found that CPAP treatment was sufficiently efficacious for them to persist with daily compliance with treatment.

In summary, this review of children and youth offered or commenced on CPAP through the CCDHB paediatric sleep service over the last 15 years highlights the need for increased availability of services for these high-risk patients. While we have greatly increased our ability to provide an assessment and treatment service for infants and children with persistent symptoms of OSA, we still have quite a way to go to ensure we support our patients to achieve optimal treatment adherence, especially with regard to our young Māori patients. To make improvements in this area we need to ensure we work with culturally appropriate support services, both in the hospital and the community. A qualitative research approach would be valuable to try to understand differences in compliance rates by both age and ethnicity. Services also need to be free for all. We have noted that the need to start paying for consumable equipment can be a barrier to transition to adult services. As we observe the tsunami of referrals for adults requiring treatment of OSA by CPAP, we also need to ensure there is optimal service provision for children and youth with significant OSA. Given the risks to children and youth of suboptimal developmental progress when OSA is untreated, and lifetime increased risks of hypertension and associated cardiovascular morbidity, this area of clinical need must be given greater priority.

Summary

Abstract

Aim

To document the establishment of a Paediatric Continuous Positive Airway Pressure (CPAP) service within the Wellington Region, and review outcomes over the last 15 years.

Method

A retrospective audit of the Paediatric Sleep Service records including clinic letters and polysomnography (PSG) studies for all paediatric patients commenced on CPAP treatment, or for whom CPAP treatment was offered, from November 2005 to December 2020. Data were collected on demographics, medical diagnoses, indications for respiratory support, ENT involvement and surgery. Factors related to CPAP use were also recorded.

Results

Seventy-four children were offered CPAP in the time frame, 52 (70%) male. The age range at onset of CPAP treatment was <1 year of age to 23 years with 12 cases ≥16 years of age. There were 3 (4%) cases presenting before 2006, 11 (15%) cases from 2006–2010, 16 (22%) cases from 2011–2015 and 44 (59%) cases between 2016–2020. Ethnicities included were, 32 (43%) NZ European, 18 (24%) Māori, 19 (26%) Pacific and 5 (7%) Indian/Asian. The most common primary diagnoses were Obesity 21 (28%), Down Syndrome 10 (14%) and Craniofacial abnormalities 8 (11%). One family declined a CPAP trial and there were eight failed CPAP trials. For the remaining 65 patients, compliance with treatment was good/usually good for 25, variable for 19, and poor for 21. Māori patients were less likely to have good/usually good compliance than NZ European and Pacific patients (25% versus 44% and 47% respectively).

Conclusion

Referrals for CPAP treatment in the paediatric age range are increasing and obesity is the commonest co-morbidity. Services need to be culturally appropriate to ensure the best outcomes.

Author Information

Professor Dawn Elder: Professor and HOD, Department of Paediatrics and Child Health, University of Otago, Wellington, Child Health Services, Capital and Coast DHB. Dr Sophie Gandhi: Medical Student (at time study undertaken), Otago Medical School. Associate Professor Angela Campbell: Manager, WellSleep, Department of Medicine, University of Otago Wellington.

Acknowledgements

Sophie Gandhi gathered these data and undertook initial analysis as part of an elective period in her Trainee Intern year at Otago Medical School. Thanks to Tricia Martin, Respiratory Nurse, and the WellSleep sleep physiology team for their significant contributions to the clinical management of these patients.

Correspondence

Prof. Dawn Elder: HOD, Department of Paediatrics and Child Health, University of Otago, Wellington. 0212796140.

Correspondence Email

dawn.elder@otago.ac.nz

Competing Interests

WellSleep has a contract to provide sleep assessment and treatments services for all age groups for CCDHB, HVDHB and WrDHB. Professor Dawn Elder receives remuneration to supervise and report sleep studies undertaken in children and youth at WellSleep.

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