The commonly used painkiller diclofenac is associated with an increased risk of major cardiovascular events such as heart attack and stroke, reported a study in BMJ.

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) for treating pain and inflammation. But its cardiovascular risks compared with those of other NSAIDs had never been examined in large trials. So a research team led by Morten Schmidt at Aarhus University Hospital in Denmark, examined the cardiovascular risks of diclofenac compared with no NSAIDs, other traditional NSAIDs, and paracetamol.

Participants were split into low, moderate, and high baseline cardiovascular risk. Average age was 46 to 49 for those taking NSAIDs and 56 years among those taking paracetamol.

After taking account of potentially influential factors, taking diclofenac during the study period was associated with an increased rate of major adverse cardiovascular events within 30 days compared with taking other traditional NSAIDs (ibuprofen or naproxen) or starting paracetamol. Events included irregular heartbeat or flutter, ischemic stroke, heart failure, and heart attack.

The increased risks applied to men and women of all ages and also at low doses of diclofenac. Taking diclofenac was also associated with an increased rate of cardiac death compared with no NSAIDs, and an increased risk of upper gastrointestinal bleeding compared with no NSAIDs and taking ibuprofen or paracetamol, but not with naproxen.