Non-steroidal anti-inflammatory drugs increase risk of atrial fibrillation

Adding to the list of concerns that clinicians and patients should be vigilant about when using non-steroidal anti-inflammatory drugs (NSAIDs), a research published in the British Journal of Medicine offers evidence for a strong increase in risk of atrial fibrillation (a type of cardiac arrhythmia or 'heart flutter'). The authors state:

"Atrial fibrillation is the most common rhythm disorder observed in clinical practice...It is associated with increased mortality and morbidity, mainly due to haemodynamic impairments that exacerbate or even cause heart failure, and a threefold to fourfold increased risk of thromboembolic stroke...Any confirmed association between use of NSAIDs and atrial fibrillation would have major clinical and public health implications. Older people are of special concern because the prevalence of use of NSAIDs and the incidence of atrial fibrillation increase with age. To address the limitations of the existing literature, we conducted a large population based case-control study examining whether and to what extent use of NSAIDs increases the risk of atrial fibrillation or flutter.

In their case-control study they the examined the data for 32,602 patients diagnosed with atrial fibrillation compared to 325,918 age and sex matched control subjects, correlating specifically with current, recent and long term use of NSAIDs. They obtained results that demonstrate a particular concern for new users:

"Compared with no use, the incidence rate ratio associating current drug use with atrial fibrillation or flutter was 1.33 for non-selective NSAIDs and 1.50 for COX 2 inhibitors. Adjustments for age, sex, and risk factors for atrial fibrillation or flutter reduced the incidence rate ratio to 1.17 for non-selective NSAIDs and 1.27 for COX 2 inhibitors. Among new users, the adjusted incidence rate ratio was 1.46 for non-selective NSAIDs and 1.71 for COX 2 inhibitors."

In other words, atrial fibrillation was increased for new users by 46% for non-selective NSAIDs and 71% for COX 2 inhibitors (17% and 27% respectively for all users taken together). Their conclusions are important for practitioners to bear in mind when designing strategies to control inflammation, especially considering that other evidence-based anti-inflammatory agents without this troubling risk profile are available:

"Use of non-aspirin NSAIDs was associated with an increased risk of atrial fibrillation or flutter. Compared with non-users, the association was strongest for new users, with a 40-70% increase in relative risk (lowest for non-selective NSAIDs and highest for COX 2 inhibitors). Our study thus adds evidence that atrial fibrillation or flutter needs to be added to the cardiovascular risks to be considered when prescribing NSAIDs."