Statins, fibrates, and venous thromboembolism: a meta-analysis

The aim is to make a systematic review of the literature to assess the effect of lipid-lowering drugs on venous thromboembolism (VTE) occurrence. MEDLINE and EMBASE databases were searched to identify studies that evaluated the effect of lipid-lowering drugs, in particular statins and fibrates, on VTE risk until April 2009. A scoring system was used to divide studies into two quality categories. Odds ratios (ORs) and 95% confidence intervals (CIs) were then calculated and pooled using a fixed and a random-effects model. Statistical heterogeneity was evaluated through the use of I(2) statistics. Three randomized controlled trials (RCTs), three cohort, and eight case-control studies were included in our systematic review, for a total of 863 805 patients. Statins use significantly reduced VTE risk [OR, 0.81; 95% CI, 0.66-0.99, random-effect model)]. There was a very high heterogeneity among the studies (I(2) > 80%). The use of fibrates was associated with a significant increase in the risk of VTE (OR, 1.58; 95% CI, 1.23-2.02), without heterogeneity (I(2) = 0%). Data on other lipid-lowering drugs were lacking. This meta-analysis of available literature suggests that statins may lower the risk of VTE, whereas fibrates may increase this risk. Due to several methodological limitations, this conclusion should be considered with caution, and additional, specifically designed RCTs are warranted