Fish oils fail to prevent cardiovascular events in diabetics

The use of fish derived n-3 fatty acids following myocardial infarction has been shown to be beneficial in preventing further cardiovascular events and reducing mortality, particularly from sudden cardiac death. However the effects of these drugs in preventing cardiovascular events in high risk patients with (or at risk for) type 2 diabetes mellitus, but who are otherwise stable, are unknown. In the double-blind, multi-centre ORIGIN study 12,536 patients who had impaired fasting glucose, impaired glucose tolerance, or diabetes, were randomised in a 2-by-2 factorial design to receive either a 1-g capsule of n-3 fatty acids or placebo daily (with the other arm of the study randomising to receive either insulin glargine or standard care). Mean age of participants was 64 and 59% had had a previous cardiovascular event at baseline. The primary outcome was death from cardiovascular causes. After a median follow up of 6.2 years there was no significant difference between the n-3 fatty acids and placebo arms as regards the primary outcome (574 patients [9.1%] vs. 581 patients [9.3%];HR, 0.98; 95% CI, 0.87 to 1.10; P=0.72). The use of n-3 fatty acids also had no significant effect on the rates of major vascular events (P=0.81), death from any cause (P=0.63), or death from arrhythmia (P=0.26). Similarly, the use of insulin glargine in the other arm of the study failed to improve cardiovascular outcomes.

Conclusions:

Supplementation with 1 g of n-3 fatty acids in stable patients with dysglycemia or frank diabetes at risk of cardiovascular events has a neutral effect on outcomes.

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