A systematic review and meta-analysis has revisited the effects of rosiglitazone treatment upon cardiovascular risk and mortality, additionally examining whether different analytical methods might influence the conclusions found in clinical trials.  Researchers analysed trials where individual patient level data (IPD) was available (where the combined outcome involved acute myocardial infarction, heart failure, cardiovascular related death and non-cardiovascular related death), contrasting this to trials where IPD was unavailable (where the outcome involved only myocardial infarction and cardiovascular related death, determined using summary level data). Eligible trials included 33 where IPD was available (21,156 patients), 103 where IPD was unavailable in the meta-analysis of myocardial infarction (21,156 patients) and 103 where IPD was unavailable in the meta-analysis of cardiovascular related deaths (22,772 patients). It was found that more myocardial infarctions and less cardiovascular related deaths were identified if using IPD rather than summary level data in a majority of trials. In trials where IPD was available, rosiglitazone use was associated with a 33% increased risk of the combined outcome (odds ratio 1.33, 95% CI 1.09-1.61), and increased odds ratios for each of the individual outcomes. Odds ratios for myocardial infarction and cardiovascular related death were less in trials where IPD was unavailable. These results not only confirm the association between rosiglitazone and increased cardiovascular risk, but highlight the importance of IPD sharing and transparency among clinical trials and meta-analyses. Full details of the study can be found here.

Contributed by Australian Medication Safety Services Associate – Isabella Singh