NSAID Use Increases Risk of Atrial Arrhythmias

The fact that use of NSAIDs is associated with an increase in multiple adverse cardiovascular outcomes, such as cardiovascular death, myocardial infarction, stroke, and heart failure, has been well recognized for some time. More recently, this class of medications has been found also to be associated with an increase in atrial arrhythmias, such as atrial fibrillation (AF) and atrial flutter (AFL). These findings were published in the British Medical Journal and carry important implications for primary care providers who often prescribe NSAIDs, for a wide variety ills.

This was a very large population-based case-control study of 32,602 undifferentiated subjects from Northern Denmark with an inpatient or outpatient diagnosis of AF or AFL. Case patients were compared with 325,918 age- and sex-matched controls and risk of exposure to NSAIDs was assessed (either current or prior and selective or non-selective COX inhibitors). The overall incidence of NSAID use was 7% in controls and 9% in cases. Using a conditional logistic regression model and after adjusting for age, sex, and AF/AFL risk factors, the authors reported that the incidence of arrhythmia was 1.17 times greater with non-selective NSAID use and 1.27 times greater with COX-2 selective inhibitors. In NSAID-naive patients (new users) this association was even stronger; there was a 40% to 70% increase in relative risk with nonselective and COX-2–selective NSAID use, respectively.

The study’s population-based design allowed researchers the advantage of assessing a real-world population, rather than a highly selected cohort from a clinical trial. Furthermore, it demonstrates that despite their known adverse risk profile, use of this class of medications is not insignificant (7% to 9% of patients at any given time). Therefore, primary care providers need to consider the risk of atrial arrhythmias when determining the risk-benefit profile of a patient being considered for NSAID therapy. This is especially true in those in whom the medication is used for the first time, because the risk in these patients of developing AF/AFL is the highest in this cohort. The relative risk remains lower for non-selective NSAIDs than for COX-2–selective NSAIDs. Patients, too, should be aware of the risks associated with NSAID use in order to participate effectively in treatment decisions. 

References:

Schmidt M, Christiansen CF, Mehnert F, et al. Non-steroidal anti-inflammatory drug use and risk of atrial fibrillation or flutter: population based case-control study. BMJ. 2011;343:d3450.