Understanding the NSAID related risk of vascular events

Concern is growing about an increased risk of thrombotic events (including myocardial infarction and stroke) during the use of non-steroidal anti-inflammatory drugs (NSAIDs), in particular the so called selective cyclo-oxygenase-2 (COX 2) inhibitors. Although clinical trials give conflicting results with respect to the incidence of vascular events, increasing evidence shows that a class effect might exist for selective COX 2 inhibitors. Even before the massive introduction of selective COX 2 inhibitors, observational studies showed that the use of NSAIDs causes congestive heart failure in elderly patients.1,2 Conversely, the discontinuation of NSAIDs has also been associated with increased risk of myocardial infarction, especially in the first several weeks after stopping chronic NSAID treatment.3Many different mechanisms could explain the different effects of classic NSAIDs and selective COX 2 inhibitors in relation to thrombotic vascular events. In this review we link biochemical facts concerning NSAIDs and COX inhibitors with data from clinical trials.