View Article PDF

In 2016, neurological disease was responsible for the death of almost three million people globally.1 Its impact will continue to grow as countries become more socio-economically developed and reduce preventable deaths from infectious disease, malnutrition and pregnancy-related causes.

New Zealand already shoulders a heavy burden in this respect; neurological disease is now the 3rd highest cause of death behind cardiovascular disease and cancer, and has overtaken chronic respiratory disease as a cause of death among New Zealanders.1 In addition, the impact on patients cannot be overemphasised; many neurological diseases are lifelong and degenerative, with a catastrophic personal impact on patients’ lives, and economic implications for the individual and wider society. In New Zealand, they are the 4th highest cause of years of life lost to disability.1

Motor neuron disease (MND) is one such group of neurodegenerative diseases, characterised by progressive deterioration of upper and lower motor neurons. MND is more common in men, with a peak incidence in the 7th decade.2 Some MNDs are inherited, but in most cases the causes are not known. In sporadic MNDs, environmental, toxic, viral or genetic factors may be implicated. Recent studies have suggested that the incidence of MND in New Zealand may be higher than in Europe and North America.3–6 The purpose of this observational study was to calculate the incidence and characterise the demographics of MND within the MidCentral District Health Board region, which provides care for 174,340 people living in the southern region of North Island.

This study is in response to recent calls for further data on the regional incidence of MND within New Zealand,3 and complements previous studies on incidence in the Hawke’s Bay4 and Canterbury5 regions, and prevalence in the Wellington6 region. It is also in line with the World Health Organization’s Sustainable Development Goals for 2030,7 which call for further research into non-communicable disease, aiming to reduce premature mortality from such causes by one-third through prevention and treatment. It is hoped that further epidemiological data on MND will provide the necessary background for future studies into potential environmental risk factors.

Method

Patients with a new diagnosis of motor neurone disease between 1 February 2013 and 31 January 2018 were identified using clinical coding data at Palmerston North Hospital. All outpatient visits and inpatient encounters containing the codes ‘MND’, ‘Motor Neurone Disease’, ‘ALS,’ or ‘Amyotrophic Lateral Sclerosis’ were individually screened to confirm a new diagnosis of MND received during the above period via both clinical (confirmation by a neurologist) and neurophysiological (needle electromyography) criteria. All cases had to meet the Awaji criteria for ALS.8 The following data were collected: gender, age at diagnosis, date of diagnosis and ethnicity. In addition, we collected data on residential address to identify potential geographical clusters of MND.

DHB protocol for ethical approval was followed; no ethics committee approval was required for this study as it involved analysis of pre-existing data, with no patient contact or interventions carried out. Incidence was calculated as new cases/100,000 per year for the census-derived total population and then separately for the population aged 65 and over, to account for the strong association between MND and age groups.

Figure 1: Search strategy flow diagram of included cases.

c

Results

Twenty-five patients with a new diagnosis of MND were identified during the five-year study period. The male:female ratio was 13:12, in keeping with existing studies. Mean and median age at diagnosis were 69 and 72 respectively (range 38–84). Of the 25 patients, 21 (84%) were of European descent and two (8%) of Māori descent. Ethnicity could not be determined for two patients. Incidence was 2.9 per 100,000/year for the total population, and 12.7 per 100,000/year for the population aged 65 and over (which accounts for 18% of the total population). No geographical clusters emerged accounting for population density by visual evaluation using clustering of cases on 2013 census map for population and dwellings (no formal analysis was undertaken due to the low number of cases). Individual data for all study subjects is shown in Table 1.

Table 1: Individual characteristics of confirmed cases.

Discussion

This study is the first to examine incidence of MND within MidCentral Region, and thus provides important epidemiological data for future research on MND within New Zealand. It does however have several limitations. First, ‘borderline’ cases with symptoms or EMG results which were suggestive of potential MND (but not yet definitive) may later prove to have had the disease in early stages, with the result that several early cases of MND were excluded from the study. Second, our chosen search terms were ‘MND’ and its most common subtype ‘ALS’ (and their unabbreviated forms), which may have excluded patients with less common subtypes of the disease from the study. This illustrates a relevant point for future studies; the disease includes a broad spectrum of different conditions, and the link with ‘MND’ is not yet fully understood for many of these.

This study answers recent calls to improve epidemiological data on MND in New Zealand, in light of earlier regional studies suggesting a higher incidence than in similarly developed countries; this data may underlie specific genetic and environmental risk factors, as suggested by Scotter.3 A recent systematic analysis for the Global Burden of Disease Study 20159 found geographical variation in the distribution of MND, with highest rates in highest income areas. Reviews of epidemiological studies in Europe and North America have suggested a regional incidence between 1.8910 and 2.082 per 100,000/year. Studies within New Zealand have found an incidence of 2.5 per 100,000/year and 3.3 per 100,000/year in Hawke’s Bay4 and Canterbury5 regions respectively. Our calculated incidence of 2.9/100,000 (in a population with median age of 37 years) corroborates the higher incidence of MND found in other regions of New Zealand compared with other areas of the world, including studies evaluated in a previous systematic review, in similar populations with median age between 36 and 38 years.2 Further, incidence of MND within New Zealand appears to be increasing in recent decades,5 and a recent study by Cao et al11 found the New Zealand mortality rate was higher than comparable international studies, postulating a potential association with caucasian genetics but also the possibility of additional genetic factors specific to the New Zealand population. Further analysis of the MND burden in New Zealand is necessary in the light of these findings, specifically identifying incidence in other regions and potential geographical clusters. This will lay the groundwork for the identification of reasons behind the apparent high and increasing incidence of the disease within New Zealand.

Summary

Abstract

Aim

The aims of this observational study were firstly to calculate annual incidence of motor neurone disease (MND) within the midcentral region of New Zealand and secondly to characterise the demographics of this patient group, including age, sex, ethnicity and geographical distribution within the region.

Method

Patients with a new diagnosis of MND over a five-year period (1 February 2013-31 January 2018) were identified via a clinical coding search of all outpatient and inpatient encounters. Records were then individually screened to confirm a new diagnosis of MND via both clinical (confirmation by a neurologist) and neurophysiological (needle electromyography) criteria.

Results

Twenty-five new diagnoses of MND were identified. The incidence was 2.9 per 100,000/year. Mean and median age at diagnosis were 69 and 72 respectively (range 38-84), and the male:female ratio was 13:12. Of the 25 identified cases, 21 (84%) were of European descent, two (8%) of Mori descent, and two of undetermined ethnicity.\u00a0

Conclusion

The findings from this study (incidence of 2.9/100,000) are in concordance with the higher incidence of MND found in other regions of New Zealand compared with other areas of the world. Further studies are warranted to investigate incidence in other regions, thereby building the foundations for the study of genetic and environmental factors.

Author Information

- Alexandra Caulfield, Masters Student in Global Health, Karolinska Institutet, Sweden; Pietro Cariga, Consultant Neurologist, Palmerston North Hospital, Palmerston North.-

Acknowledgements

Dr Marta Rodriguez, Consultant Neurologist, Department of Neurology, Palmerston North Hospital, Palmerston North; Quentin Bourke, Analytics Department, Palmerston North Hospital, Palmerston North.

Correspondence

Dr Pietro Cariga, Department of Neurology, Palmerston North Hospital, 50 Ruahine Street, Roslyn, Palmerston North 4442.

Correspondence Email

pietro.cariga@midcentraldhb.govt.nz

Competing Interests

Nil.

  1. Institute for Health Metrics and Evaluation (IHME). GBD Compare. Seattle, WA: IHME, University of Washington, 2015. Available from http://vizhub.healthdata.org/gbd-compare (Accessed [2 October 2018]).
  2. Chio A, Logroscino G, Traynor BJ, et al. Global Epidemiology of Amyotrophic Lateral Sclerosis: a Systematic Review of the Published Literature. Neuroepidemiology. 2013; 41(2):118–130.
  3. Scotter EL. Motor Neurone Disease: bringing New Zealand patients onto the world stage. [editorial]. N Z Med J. 2015; 1409:12–14.
  4. Baker PC. Incidence of motor neurone disease in Hawke’s Bay and Gisborne/East Coast. N Z Med J. 2015; 128(1413):79–80.
  5. Murphy M, Quinn S, Young J, et al. Increasing incidence of ALS in Canterbury, New Zealand: a 22- year study. Neurology. 2008 Dec 2; 71(23):1889–95.
  6. Dayal V, Rosemergy I, Turnbull J. Motor neurone disease in the greater Wellington region: an observational study. N Z Med J. 2015; 128(1409):29–34.
  7. UN General Assembly, Transforming our world: the 2030 Agenda for Sustainable Development, 21 October 2015, A/RES/70/1. Available from http://www.refworld.org/docid/57b6e3e44.html (Accessed [2 October 2018]).
  8. de Carvalho M, Dengler R, Eisen A, et al. Electrodiagnostic criteria for diagnosis of ALS. Clin Neurophysiol. 2008; 119(3):497–503.
  9. GBD 2015 Neurological Disorders Collaborator Group. Global, regional, and national burden of neurological disorders during 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet Neurology Nov 2017.
  10. Worms PM. The epidemiology of motor neuron diseases: a review of recent studies. J Neurol Sci. 2001 Oct 15; 191(1–2):3–9.
  11. Cao MC, Chancellor A, Charleston A, et al. Motor neuron disease mortality rates in New Zealand 1992–2013. Amyotroph Lateral Scler Frontotemporal Degener. 2018 May; 19(3–4):285–293.

For the PDF of this article,
contact nzmj@nzma.org.nz

View Article PDF

In 2016, neurological disease was responsible for the death of almost three million people globally.1 Its impact will continue to grow as countries become more socio-economically developed and reduce preventable deaths from infectious disease, malnutrition and pregnancy-related causes.

New Zealand already shoulders a heavy burden in this respect; neurological disease is now the 3rd highest cause of death behind cardiovascular disease and cancer, and has overtaken chronic respiratory disease as a cause of death among New Zealanders.1 In addition, the impact on patients cannot be overemphasised; many neurological diseases are lifelong and degenerative, with a catastrophic personal impact on patients’ lives, and economic implications for the individual and wider society. In New Zealand, they are the 4th highest cause of years of life lost to disability.1

Motor neuron disease (MND) is one such group of neurodegenerative diseases, characterised by progressive deterioration of upper and lower motor neurons. MND is more common in men, with a peak incidence in the 7th decade.2 Some MNDs are inherited, but in most cases the causes are not known. In sporadic MNDs, environmental, toxic, viral or genetic factors may be implicated. Recent studies have suggested that the incidence of MND in New Zealand may be higher than in Europe and North America.3–6 The purpose of this observational study was to calculate the incidence and characterise the demographics of MND within the MidCentral District Health Board region, which provides care for 174,340 people living in the southern region of North Island.

This study is in response to recent calls for further data on the regional incidence of MND within New Zealand,3 and complements previous studies on incidence in the Hawke’s Bay4 and Canterbury5 regions, and prevalence in the Wellington6 region. It is also in line with the World Health Organization’s Sustainable Development Goals for 2030,7 which call for further research into non-communicable disease, aiming to reduce premature mortality from such causes by one-third through prevention and treatment. It is hoped that further epidemiological data on MND will provide the necessary background for future studies into potential environmental risk factors.

Method

Patients with a new diagnosis of motor neurone disease between 1 February 2013 and 31 January 2018 were identified using clinical coding data at Palmerston North Hospital. All outpatient visits and inpatient encounters containing the codes ‘MND’, ‘Motor Neurone Disease’, ‘ALS,’ or ‘Amyotrophic Lateral Sclerosis’ were individually screened to confirm a new diagnosis of MND received during the above period via both clinical (confirmation by a neurologist) and neurophysiological (needle electromyography) criteria. All cases had to meet the Awaji criteria for ALS.8 The following data were collected: gender, age at diagnosis, date of diagnosis and ethnicity. In addition, we collected data on residential address to identify potential geographical clusters of MND.

DHB protocol for ethical approval was followed; no ethics committee approval was required for this study as it involved analysis of pre-existing data, with no patient contact or interventions carried out. Incidence was calculated as new cases/100,000 per year for the census-derived total population and then separately for the population aged 65 and over, to account for the strong association between MND and age groups.

Figure 1: Search strategy flow diagram of included cases.

c

Results

Twenty-five patients with a new diagnosis of MND were identified during the five-year study period. The male:female ratio was 13:12, in keeping with existing studies. Mean and median age at diagnosis were 69 and 72 respectively (range 38–84). Of the 25 patients, 21 (84%) were of European descent and two (8%) of Māori descent. Ethnicity could not be determined for two patients. Incidence was 2.9 per 100,000/year for the total population, and 12.7 per 100,000/year for the population aged 65 and over (which accounts for 18% of the total population). No geographical clusters emerged accounting for population density by visual evaluation using clustering of cases on 2013 census map for population and dwellings (no formal analysis was undertaken due to the low number of cases). Individual data for all study subjects is shown in Table 1.

Table 1: Individual characteristics of confirmed cases.

Discussion

This study is the first to examine incidence of MND within MidCentral Region, and thus provides important epidemiological data for future research on MND within New Zealand. It does however have several limitations. First, ‘borderline’ cases with symptoms or EMG results which were suggestive of potential MND (but not yet definitive) may later prove to have had the disease in early stages, with the result that several early cases of MND were excluded from the study. Second, our chosen search terms were ‘MND’ and its most common subtype ‘ALS’ (and their unabbreviated forms), which may have excluded patients with less common subtypes of the disease from the study. This illustrates a relevant point for future studies; the disease includes a broad spectrum of different conditions, and the link with ‘MND’ is not yet fully understood for many of these.

This study answers recent calls to improve epidemiological data on MND in New Zealand, in light of earlier regional studies suggesting a higher incidence than in similarly developed countries; this data may underlie specific genetic and environmental risk factors, as suggested by Scotter.3 A recent systematic analysis for the Global Burden of Disease Study 20159 found geographical variation in the distribution of MND, with highest rates in highest income areas. Reviews of epidemiological studies in Europe and North America have suggested a regional incidence between 1.8910 and 2.082 per 100,000/year. Studies within New Zealand have found an incidence of 2.5 per 100,000/year and 3.3 per 100,000/year in Hawke’s Bay4 and Canterbury5 regions respectively. Our calculated incidence of 2.9/100,000 (in a population with median age of 37 years) corroborates the higher incidence of MND found in other regions of New Zealand compared with other areas of the world, including studies evaluated in a previous systematic review, in similar populations with median age between 36 and 38 years.2 Further, incidence of MND within New Zealand appears to be increasing in recent decades,5 and a recent study by Cao et al11 found the New Zealand mortality rate was higher than comparable international studies, postulating a potential association with caucasian genetics but also the possibility of additional genetic factors specific to the New Zealand population. Further analysis of the MND burden in New Zealand is necessary in the light of these findings, specifically identifying incidence in other regions and potential geographical clusters. This will lay the groundwork for the identification of reasons behind the apparent high and increasing incidence of the disease within New Zealand.

Summary

Abstract

Aim

The aims of this observational study were firstly to calculate annual incidence of motor neurone disease (MND) within the midcentral region of New Zealand and secondly to characterise the demographics of this patient group, including age, sex, ethnicity and geographical distribution within the region.

Method

Patients with a new diagnosis of MND over a five-year period (1 February 2013-31 January 2018) were identified via a clinical coding search of all outpatient and inpatient encounters. Records were then individually screened to confirm a new diagnosis of MND via both clinical (confirmation by a neurologist) and neurophysiological (needle electromyography) criteria.

Results

Twenty-five new diagnoses of MND were identified. The incidence was 2.9 per 100,000/year. Mean and median age at diagnosis were 69 and 72 respectively (range 38-84), and the male:female ratio was 13:12. Of the 25 identified cases, 21 (84%) were of European descent, two (8%) of Mori descent, and two of undetermined ethnicity.\u00a0

Conclusion

The findings from this study (incidence of 2.9/100,000) are in concordance with the higher incidence of MND found in other regions of New Zealand compared with other areas of the world. Further studies are warranted to investigate incidence in other regions, thereby building the foundations for the study of genetic and environmental factors.

Author Information

- Alexandra Caulfield, Masters Student in Global Health, Karolinska Institutet, Sweden; Pietro Cariga, Consultant Neurologist, Palmerston North Hospital, Palmerston North.-

Acknowledgements

Dr Marta Rodriguez, Consultant Neurologist, Department of Neurology, Palmerston North Hospital, Palmerston North; Quentin Bourke, Analytics Department, Palmerston North Hospital, Palmerston North.

Correspondence

Dr Pietro Cariga, Department of Neurology, Palmerston North Hospital, 50 Ruahine Street, Roslyn, Palmerston North 4442.

Correspondence Email

pietro.cariga@midcentraldhb.govt.nz

Competing Interests

Nil.

  1. Institute for Health Metrics and Evaluation (IHME). GBD Compare. Seattle, WA: IHME, University of Washington, 2015. Available from http://vizhub.healthdata.org/gbd-compare (Accessed [2 October 2018]).
  2. Chio A, Logroscino G, Traynor BJ, et al. Global Epidemiology of Amyotrophic Lateral Sclerosis: a Systematic Review of the Published Literature. Neuroepidemiology. 2013; 41(2):118–130.
  3. Scotter EL. Motor Neurone Disease: bringing New Zealand patients onto the world stage. [editorial]. N Z Med J. 2015; 1409:12–14.
  4. Baker PC. Incidence of motor neurone disease in Hawke’s Bay and Gisborne/East Coast. N Z Med J. 2015; 128(1413):79–80.
  5. Murphy M, Quinn S, Young J, et al. Increasing incidence of ALS in Canterbury, New Zealand: a 22- year study. Neurology. 2008 Dec 2; 71(23):1889–95.
  6. Dayal V, Rosemergy I, Turnbull J. Motor neurone disease in the greater Wellington region: an observational study. N Z Med J. 2015; 128(1409):29–34.
  7. UN General Assembly, Transforming our world: the 2030 Agenda for Sustainable Development, 21 October 2015, A/RES/70/1. Available from http://www.refworld.org/docid/57b6e3e44.html (Accessed [2 October 2018]).
  8. de Carvalho M, Dengler R, Eisen A, et al. Electrodiagnostic criteria for diagnosis of ALS. Clin Neurophysiol. 2008; 119(3):497–503.
  9. GBD 2015 Neurological Disorders Collaborator Group. Global, regional, and national burden of neurological disorders during 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet Neurology Nov 2017.
  10. Worms PM. The epidemiology of motor neuron diseases: a review of recent studies. J Neurol Sci. 2001 Oct 15; 191(1–2):3–9.
  11. Cao MC, Chancellor A, Charleston A, et al. Motor neuron disease mortality rates in New Zealand 1992–2013. Amyotroph Lateral Scler Frontotemporal Degener. 2018 May; 19(3–4):285–293.

For the PDF of this article,
contact nzmj@nzma.org.nz

View Article PDF

In 2016, neurological disease was responsible for the death of almost three million people globally.1 Its impact will continue to grow as countries become more socio-economically developed and reduce preventable deaths from infectious disease, malnutrition and pregnancy-related causes.

New Zealand already shoulders a heavy burden in this respect; neurological disease is now the 3rd highest cause of death behind cardiovascular disease and cancer, and has overtaken chronic respiratory disease as a cause of death among New Zealanders.1 In addition, the impact on patients cannot be overemphasised; many neurological diseases are lifelong and degenerative, with a catastrophic personal impact on patients’ lives, and economic implications for the individual and wider society. In New Zealand, they are the 4th highest cause of years of life lost to disability.1

Motor neuron disease (MND) is one such group of neurodegenerative diseases, characterised by progressive deterioration of upper and lower motor neurons. MND is more common in men, with a peak incidence in the 7th decade.2 Some MNDs are inherited, but in most cases the causes are not known. In sporadic MNDs, environmental, toxic, viral or genetic factors may be implicated. Recent studies have suggested that the incidence of MND in New Zealand may be higher than in Europe and North America.3–6 The purpose of this observational study was to calculate the incidence and characterise the demographics of MND within the MidCentral District Health Board region, which provides care for 174,340 people living in the southern region of North Island.

This study is in response to recent calls for further data on the regional incidence of MND within New Zealand,3 and complements previous studies on incidence in the Hawke’s Bay4 and Canterbury5 regions, and prevalence in the Wellington6 region. It is also in line with the World Health Organization’s Sustainable Development Goals for 2030,7 which call for further research into non-communicable disease, aiming to reduce premature mortality from such causes by one-third through prevention and treatment. It is hoped that further epidemiological data on MND will provide the necessary background for future studies into potential environmental risk factors.

Method

Patients with a new diagnosis of motor neurone disease between 1 February 2013 and 31 January 2018 were identified using clinical coding data at Palmerston North Hospital. All outpatient visits and inpatient encounters containing the codes ‘MND’, ‘Motor Neurone Disease’, ‘ALS,’ or ‘Amyotrophic Lateral Sclerosis’ were individually screened to confirm a new diagnosis of MND received during the above period via both clinical (confirmation by a neurologist) and neurophysiological (needle electromyography) criteria. All cases had to meet the Awaji criteria for ALS.8 The following data were collected: gender, age at diagnosis, date of diagnosis and ethnicity. In addition, we collected data on residential address to identify potential geographical clusters of MND.

DHB protocol for ethical approval was followed; no ethics committee approval was required for this study as it involved analysis of pre-existing data, with no patient contact or interventions carried out. Incidence was calculated as new cases/100,000 per year for the census-derived total population and then separately for the population aged 65 and over, to account for the strong association between MND and age groups.

Figure 1: Search strategy flow diagram of included cases.

c

Results

Twenty-five patients with a new diagnosis of MND were identified during the five-year study period. The male:female ratio was 13:12, in keeping with existing studies. Mean and median age at diagnosis were 69 and 72 respectively (range 38–84). Of the 25 patients, 21 (84%) were of European descent and two (8%) of Māori descent. Ethnicity could not be determined for two patients. Incidence was 2.9 per 100,000/year for the total population, and 12.7 per 100,000/year for the population aged 65 and over (which accounts for 18% of the total population). No geographical clusters emerged accounting for population density by visual evaluation using clustering of cases on 2013 census map for population and dwellings (no formal analysis was undertaken due to the low number of cases). Individual data for all study subjects is shown in Table 1.

Table 1: Individual characteristics of confirmed cases.

Discussion

This study is the first to examine incidence of MND within MidCentral Region, and thus provides important epidemiological data for future research on MND within New Zealand. It does however have several limitations. First, ‘borderline’ cases with symptoms or EMG results which were suggestive of potential MND (but not yet definitive) may later prove to have had the disease in early stages, with the result that several early cases of MND were excluded from the study. Second, our chosen search terms were ‘MND’ and its most common subtype ‘ALS’ (and their unabbreviated forms), which may have excluded patients with less common subtypes of the disease from the study. This illustrates a relevant point for future studies; the disease includes a broad spectrum of different conditions, and the link with ‘MND’ is not yet fully understood for many of these.

This study answers recent calls to improve epidemiological data on MND in New Zealand, in light of earlier regional studies suggesting a higher incidence than in similarly developed countries; this data may underlie specific genetic and environmental risk factors, as suggested by Scotter.3 A recent systematic analysis for the Global Burden of Disease Study 20159 found geographical variation in the distribution of MND, with highest rates in highest income areas. Reviews of epidemiological studies in Europe and North America have suggested a regional incidence between 1.8910 and 2.082 per 100,000/year. Studies within New Zealand have found an incidence of 2.5 per 100,000/year and 3.3 per 100,000/year in Hawke’s Bay4 and Canterbury5 regions respectively. Our calculated incidence of 2.9/100,000 (in a population with median age of 37 years) corroborates the higher incidence of MND found in other regions of New Zealand compared with other areas of the world, including studies evaluated in a previous systematic review, in similar populations with median age between 36 and 38 years.2 Further, incidence of MND within New Zealand appears to be increasing in recent decades,5 and a recent study by Cao et al11 found the New Zealand mortality rate was higher than comparable international studies, postulating a potential association with caucasian genetics but also the possibility of additional genetic factors specific to the New Zealand population. Further analysis of the MND burden in New Zealand is necessary in the light of these findings, specifically identifying incidence in other regions and potential geographical clusters. This will lay the groundwork for the identification of reasons behind the apparent high and increasing incidence of the disease within New Zealand.

Summary

Abstract

Aim

The aims of this observational study were firstly to calculate annual incidence of motor neurone disease (MND) within the midcentral region of New Zealand and secondly to characterise the demographics of this patient group, including age, sex, ethnicity and geographical distribution within the region.

Method

Patients with a new diagnosis of MND over a five-year period (1 February 2013-31 January 2018) were identified via a clinical coding search of all outpatient and inpatient encounters. Records were then individually screened to confirm a new diagnosis of MND via both clinical (confirmation by a neurologist) and neurophysiological (needle electromyography) criteria.

Results

Twenty-five new diagnoses of MND were identified. The incidence was 2.9 per 100,000/year. Mean and median age at diagnosis were 69 and 72 respectively (range 38-84), and the male:female ratio was 13:12. Of the 25 identified cases, 21 (84%) were of European descent, two (8%) of Mori descent, and two of undetermined ethnicity.\u00a0

Conclusion

The findings from this study (incidence of 2.9/100,000) are in concordance with the higher incidence of MND found in other regions of New Zealand compared with other areas of the world. Further studies are warranted to investigate incidence in other regions, thereby building the foundations for the study of genetic and environmental factors.

Author Information

- Alexandra Caulfield, Masters Student in Global Health, Karolinska Institutet, Sweden; Pietro Cariga, Consultant Neurologist, Palmerston North Hospital, Palmerston North.-

Acknowledgements

Dr Marta Rodriguez, Consultant Neurologist, Department of Neurology, Palmerston North Hospital, Palmerston North; Quentin Bourke, Analytics Department, Palmerston North Hospital, Palmerston North.

Correspondence

Dr Pietro Cariga, Department of Neurology, Palmerston North Hospital, 50 Ruahine Street, Roslyn, Palmerston North 4442.

Correspondence Email

pietro.cariga@midcentraldhb.govt.nz

Competing Interests

Nil.

  1. Institute for Health Metrics and Evaluation (IHME). GBD Compare. Seattle, WA: IHME, University of Washington, 2015. Available from http://vizhub.healthdata.org/gbd-compare (Accessed [2 October 2018]).
  2. Chio A, Logroscino G, Traynor BJ, et al. Global Epidemiology of Amyotrophic Lateral Sclerosis: a Systematic Review of the Published Literature. Neuroepidemiology. 2013; 41(2):118–130.
  3. Scotter EL. Motor Neurone Disease: bringing New Zealand patients onto the world stage. [editorial]. N Z Med J. 2015; 1409:12–14.
  4. Baker PC. Incidence of motor neurone disease in Hawke’s Bay and Gisborne/East Coast. N Z Med J. 2015; 128(1413):79–80.
  5. Murphy M, Quinn S, Young J, et al. Increasing incidence of ALS in Canterbury, New Zealand: a 22- year study. Neurology. 2008 Dec 2; 71(23):1889–95.
  6. Dayal V, Rosemergy I, Turnbull J. Motor neurone disease in the greater Wellington region: an observational study. N Z Med J. 2015; 128(1409):29–34.
  7. UN General Assembly, Transforming our world: the 2030 Agenda for Sustainable Development, 21 October 2015, A/RES/70/1. Available from http://www.refworld.org/docid/57b6e3e44.html (Accessed [2 October 2018]).
  8. de Carvalho M, Dengler R, Eisen A, et al. Electrodiagnostic criteria for diagnosis of ALS. Clin Neurophysiol. 2008; 119(3):497–503.
  9. GBD 2015 Neurological Disorders Collaborator Group. Global, regional, and national burden of neurological disorders during 1990–2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet Neurology Nov 2017.
  10. Worms PM. The epidemiology of motor neuron diseases: a review of recent studies. J Neurol Sci. 2001 Oct 15; 191(1–2):3–9.
  11. Cao MC, Chancellor A, Charleston A, et al. Motor neuron disease mortality rates in New Zealand 1992–2013. Amyotroph Lateral Scler Frontotemporal Degener. 2018 May; 19(3–4):285–293.

Contact diana@nzma.org.nz
for the PDF of this article

Subscriber Content

The full contents of this pages only available to subscribers.

LOGINSUBSCRIBE