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The New Zealand Medical Journal

 Journal of the New Zealand Medical Association, 21-January-2011, Vol 124 No 1328

Can dietary supplements of vitamin E prevent haemorrhagic and ischaemic stroke?

Amongst the suggested virtues of dietary vitamin E supplements is the possibility that they may protect subjects from cardiovascular disease, including strokes. This meta-analysis reviews 9 trials involving 118,765 participants (59,357 randomised to vitamin E and 59,408 to placebo).
The follow-up data revealed that vitamin E supplements had no effect overall on the incidence of strokes. However, the risk for haemorrhagic stroke was increased by 22% and the risk of ischaemic stroke was reduced by 10%. And in terms of the absolute risk, these results translate into 1 additional haemorrhagic stroke for every 1250 individuals taking vitamin E, and 1 ischaemic stroke prevented for every 476 individuals taking vitamin E.
As haemorrhagic strokes tend to be more devastating, vitamin E appears to be of very dubious value for stroke prevention.
BMJ 2010;341:1033.

Risk of venous thromboembolism after prolonged work- and computer-related seated immobility

Case reports of an association between prolonged recreational computer-related use and venous thromboembolism (VTE) prompted this case-control study. 197 patients with proven VTE were compared with 197 patients admitted to hospital without VTE.
Prolonged work- and computer-related immobility was defined as being seated at work and on the computer at home, at least 10 hours in a 24-hour period and at least 2 hours at a time without getting up, during the 4 weeks prior to the onset of symptoms that led to VTE diagnosis.
16.8% of the patients with VTE fitted into the prolonged work etc category as compared with 9.6% of the controls (odds ratio 2.8, p=0.013).
The authors recommend dissemination of this information and advice on how to avoid the problem.
J R Soc Med 2010;103:447–54.

Placebos—do we need to know what they contain?

The medical literature is flush with randomised double-blind placebo-controlled trials. The authors of this interesting paper suggest that we are under-informed about the nature of these agents and that this may matter. They selected 4 journals—The New England Journal of Medicine, JAMA, The Lancet, and Annals of Internal Medicine for their study based on the facts that they were English language and had high impact factors over the period between January 2008 and December 2009.
Over this period they found 167 eligible studies. Most studies did not disclose the composition of the study placebo. Disclosure was less common for pills than for injections and other treatments (8.2% vs 26.7%; p=0.0002).
So they were right, we are under-informed. Rather interesting the difference between the pills and the injections. Does it matter that we don’t know? It might, for example lactose as a placebo might upset the lactose intolerant. On the other hand, the placebo might actually be therapeutically active. Interesting.
Ann Intern Med 2010:153:532–35.

More intensive lowering of LDL cholesterol?

Lowering of LDL cholesterol with standard statin regimens reduces the risk of occlusive vascular events. The question examined in this systematic review is whether more is efficacious and safe. Data from 5 trials involving 39,612 individuals are reviewed. Several statins including simvastatin, atorvastatin and pravastatin are involved in the comparative studies. In the largest study a daily dose of 20 mg of simvastatin was compared with 80 mg per day. At a median follow up of 5.1 years there was, as expected, a more marked reduction in LDL cholesterol in the higher dose regimen. The more intensive regimens produced a highly significant 15% (95%CI: 11–18; p<0.0001) further reductions in major vascular events.
The only adverse effect of note was myopathy. They note 14 subjects with rhapdomyolysis in the intensive treatment arm versus 6 cases in the standard treatment group. In particular they report no increase in the incidence of cancer in those with the lowest LDL cholesterol concentrations.
Lancet 2010;376:167-81.

Omega-3 fatty acids for the prevention of recurrent symptomatic atrial fibrillation

Apparently fish oils have proven autonomic-modulating anti-inflammatory effects on heart tissue. Hence these agents have been used to correct atrial fibrillation (AF). But, do they work?
This prospective trial was intended to evaluate the safety and efficacy of prescription omega-3 (8 g/d) or placebo for the first 7 days; prescription omega-3 (4 g/d) or placebo thereafter through week 24.
Apparently the dose used was at the higher end of the range. Adverse effects were similar. The outcome-omega-3 did not reduce recurrent AF.
JAMA 2010;304(21):2363–72.

Acute medical admissions and the weekend effect

The ‘weekend effect’ is the adverse effect that weekend admissions have on hospital outcomes (e.g. in-hospital mortality) when compared with weekday admissions.
This study retrospectively analysed data from public hospitals in Queensland during 2002/2003–2006/2007. During the study period there were 30,522 chronic obstructive pulmonary disease (COPD), 17,910 acute myocardial infarction, 4183 acute hip fracture and 1781 intracerebral haemorrhage admissions.
There was no significant weekend effect on in-hospital mortality (i.e. increase) for COPD, hip fracture or intracerebral haemorrhage. But there was a significant effect for acute myocardial infarction (p=0.007). This observation mirrors a similar study in the USA. It is suggested that the cause of the weekend unfavourable outcome is related to reduced access to invasive procedures used in the management of heart attacks. They note a possible confounding factor—such patients may have delayed admission to hospital at weekends.
Internal Medicine Journal 2010;40:777–83.
     
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