Cochrane Db Syst Rev
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Cochrane Db Syst Rev · Jan 2004
Review Meta AnalysisShort acting insulin analogues versus regular human insulin in patients with diabetes mellitus.
In short acting insulin analogues the dissociation of hexamers is facilitated, achieving peak plasma concentrations about twice as high and within approximately half the time compared to regular human insulin. According to these properties this profile resembles the shape of non-diabetic patients more than that of regular human insulins. Despite this theoretical superiority of short acting insulin analogues over regular human insulin, the risk-benefit ratio of short acting insulin analogues in the treatment of diabetic patients is still unclear. ⋯ Our analysis suggests only a minor benefit of short acting insulin analogues in the majority of diabetic patients treated with insulin. Until long term efficacy and safety data are available we suggest a cautious response to the vigorous promotion of insulin analogues. Due to fears of potentially carcinogenic and proliferative effects, most studies to date have excluded patients with advanced diabetic complications. For safety purposes, we need a long-term follow-up of large numbers of patients who use short acting insulin analogues. Furthermore, we need well designed studies in pregnant women to determine the safety profile for both the mother and the unborn child.
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Cochrane Db Syst Rev · Jan 2004
Review Meta AnalysisEffect of longer-term modest salt reduction on blood pressure.
Many randomised trials assessing the effect of salt reduction on blood pressure show reduction in blood pressure in individuals with high blood pressure. However, there is controversy about the magnitude and the clinical significance of the fall in blood pressure in individuals with normal blood pressure. Several meta-analyses of randomised salt reduction trials have been published in the last few years. However, most of these included trials of very short duration (e.g. 5 days) and included trials with salt loading followed by salt deprivation (e.g. from 20 to 1 g/day) over only a few days. These short-term experiments are not appropriate to inform public health policy which is for a modest reduction in salt intake over a prolonged period of time. A meta-analysis by Hooper et al is an important attempt to look at whether advice to achieve a long-term salt reduction (i.e. more than 6 months) in randomised trials causes a fall in blood pressure. However, most trials included in this meta-analysis achieved a small reduction in salt intake; on average, salt intake was reduced by 2 g/day. It is, therefore, not surprising that this analysis showed a small fall in blood pressure, and that a dose-response to salt reduction was not demonstrable. ⋯ Our meta-analysis demonstrates that a modest reduction in salt intake for a duration of 4 or more weeks has a significant and, from a population viewpoint, important effect on blood pressure in both individuals with normal and elevated blood pressure. These results support other evidence suggesting that a modest and long-term reduction in population salt intake could reduce strokes, heart attacks, and heart failure. Furthermore, our meta-analysis demonstrates a correlation between the magnitude of salt reduction and the magnitude of blood pressure reduction. Within the daily intake range of 3 to 12 g/day, the lower the salt intake achieved, the lower the blood pressure.
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Anticonvulsant drugs seem to be useful in clinical practice for the prophylaxis of migraine. This might be explained by a variety of actions of these drugs in the central nervous system that are probably relevant to the pathophysiology of migraine. ⋯ Anticonvulsants appear to be both effective in reducing migraine frequency and reasonably well tolerated. There is noticeable variation among individual agents, but there are insufficient data to know whether this is due to chance or variation in true efficacy. Neither clonazepam nor lamotrigine was superior to placebo (one trial each). Relatively few robust trials are available for agents other than sodium valproate/divalproex sodium. Two recently published and large trials of topiramate demonstrated reasonable efficacy, and one further trial of this agent is anticipated in the near future.
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Cochrane Db Syst Rev · Jan 2004
Review Meta AnalysisLocal versus general anaesthesia for carotid endarterectomy.
Carotid endarterectomy reduces the risk of stroke in people with recently symptomatic, severe carotid artery stenosis. However, there are significant perioperative risks which may be lessened by performing the operation under local rather than general anaesthetic. ⋯ There is insufficient evidence from randomised trials comparing carotid endarterectomy performed under local and general anaesthetic. Non-randomised studies suggest potential benefits with the use of local anaesthetic, but these studies may be biased. More randomised studies are needed.
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Cochrane Db Syst Rev · Jan 2004
ReviewPenicillins for the prophylaxis of bacterial endocarditis in dentistry.
Many dental procedures cause bacteraemia and it is believed that this may lead to bacterial endocarditis (BE) in a few people. Guidelines in many countries recommend that prior to invasive dental procedures antibiotics are administered to people at high risk of endocarditis. However, it is unclear whether the potential risks of this prophylaxis outweigh the potential benefits. ⋯ There is no evidence about whether penicillin prophylaxis is effective or ineffective against bacterial endocarditis in people at risk who are about to undergo an invasive dental procedure. There is a lack of evidence to support published guidelines in this area. It is not clear whether the potential harms and costs of penicillin administration outweigh any beneficial effect. Ethically practitioners need to discuss the potential benefits and harms of antibiotic prophylaxis with their patients before a decision is made about administration.