Updating insights into rosiglitazone and cardiovascular risk through shared data: individual patient and summary level meta-analyses

SPS commentary:

Results 33 eligible trials were identified for which individual patient level data (IPD) were available (n=21,156) and 103 trials for which IPD were not available were included in the meta-analyses for myocardial infarction (n=23,683), and 103 trials for which IPD were not available contributed to the meta-analyses for cardiovascular related death (n=221,772).

 

The researchers note their analyses offered several insights. First, a greater number of myocardial infarctions and fewer cardiovascular deaths reported in the individual patient level data compared to what had been reported for the same trials in previous reviews utilizing only publicly available summary level data. Second, confirmation of previous reports of an increased risk of heart failure—an approximately 50% increased risk. Third, rosiglitazone was associated with an increased risk of myocardial infarction risk—an approximately 17% increased risk. Both of these inferences held up regardless of how data was analysed. They add that what made their analyses particularly interesting was that after analysing individual patient level data for the 33 trials, they combined these data with publicly available summary level data from over 100 other clinical trials, and found that the magnitude of the risk of myocardial infarction decreased and was no longer statistically significant by conventional standards. They speculate these differences are a result of combining the individual patient level data with lower quality data from the studies without individual patient level data, which often had smaller sample sizes and less rigorous designs.