NSAIDs, corticosteroids and atrial fibrillation?

Evidence that a number of drugs can cause atrial fibrillation has been accumulating since the 2000s. A case-control analysis of a UK general medicine database showed statistically significant increases in the risk of chronic atrial fibrillation in patients taking NSAIDs, after as little as one month of treatment. When NSAID treatment lasted more than 30 days, the incidence was 9.4%, versus 4.7% in the control group, corresponding to a relative risk (RR) of 1.57 (95% confidence interval (95% CI): 1.15 to 2.15). Similar results were found in patients with no history of heart failure. A Danish case-control study yielded similar results. In the UK case-control study, a statistically significant increase in the risk of chronic atrial fibrillation was found in patients taking corticosteroids (5% versus 1.4% in the control group, RR=2.5, 95% CI: 1.6 to 4). The risk increased with the dose. Another Danish case-control study showed that hospitalisation for atrial fibrillation or flutter was twice as frequent among patients exposed to corticosteroids. In contrast, trials in which corticosteroids were given shortly after cardiac surgery, a highly specific setting, showed a decreased risk of atrial fibrillation. In practice, the risk of atrial fibrillation should be taken into account before deciding whether or not to prescribe a corticosteroid or an NSAID, especially to a patient with known risk factors for atrial fibrillation. The heart rate of treated patients should be closely monitored.