Steroid Meds Can Double the Risk of Afib

Many older persons with a chronic disease, such as rheumatoid arthritis, take corticosteroids as part of their treatment.  Their side effects are well known; their use is associated with an increased risk of heart attack (myocardial infarction, or MI), stroke, and heart failure, but until now such a link with irregular heart rhythms has been sparse.  This is changed by a publication in the Archives of Internal Medicine, coming from Denmark.

All patients with a first hospital diagnosis of atrial fibrillation (Afib) or atrial flutter from 1999 through 2005 in Northern Denmark were identified.  For each case, 10 population control persons, matched by age and gender, were selected.  Data on medication prescriptions were used to determine glucocorticoid steroid use, either as current or former users.

There were 20,221 people diagnosed with Afib or flutter over the 7-year period; they were matched with 202,130 controls.  In these patients, 6.4% were current corticoid users, and 11.7% had previously used them.  These rates for the controls were 2.6% and 9.9%, respectively.

These findings show that current, but not former, use of steroids was linked with a doubling of the risk for development of a cardiac irregularity disorder.  (The difference between 11.2% and 9.9% was not statistically significant.)  Higher doses of the corticosteroid were more likely to be associated with Afib or atrial flutter than lower doses. 

The findings suggest another reason for physicians to be careful in prescribing corticosteroids, and for keeping the dose as low as necessary for effectiveness.