Patients who were given blood clot-preventing antithrombotic therapy following a heart attack had an increased risk of bleeding and major cardiovascular events if also prescribed nonsteroidal anti-inflammatory drugs (NSAIDs).

Current guidelines recommend that all patients who have had a heart attack should be prescribed dual antithrombotic therapy (both aspirin and clopidogrel) for at least 12 months following the health incident, JAMA reported. Bleeding risks have been associated with antithrombotic agents, and are increased even further by NSAIDs; certain NSAID agents have also been found to inhibit the effects of aspirin and even increase the risk of cardiovascular events.

The data for the study came from nationwide administrative registries in Denmark. A team of researchers looked at 61,971 patients with an average age of 68 years, out of this sample; 34 percent filled at least one NSAID prescription. There were 18,105 deaths, 5,288 bleeding events, and 18,568 cardiovascular events over the course of the study. 

The analysis determined there was about twice the risk of bleeding with NSAID treatment compared with no NSAID treatment, and cardiovascular risk was also increased. The findings showed there was no safe therapeutic window for concomitant NSAID use, because even treatments lasting only between one and three days were linked to an increased risk of bleeding events.

"More research is needed to confirm these findings; however, physicians should exercise appropriate caution when prescribing NSAIDs for patients who have recently experienced MI," the researchers concluded.

The findings were published in a recent edition of the Journal of the American Medical Association.