– Depression increases the risk of stroke in patients with atrial fibrillation, Bruno B. Lima, MD, reported at the American Heart Association scientific sessions.

This novel finding from what’s believed to be the first prospective observational study to examine the association between depression and stroke risk in patients with atrial fibrillation (AF) raises the exciting possibility that systematic screening for depression and provision of effective antidepressant therapy in affected AF patients could reduce their risk of stroke. But clinical trials will be necessary to answer that question, noted Dr. Lima of the University of Pittsburgh.

He reported on 5,976 consecutive patients diagnosed with paroxysmal or persistent AF and placed on rhythm control medication at the University of Pittsburgh Medical Center and its affiliated clinics. Physician-diagnosed depression was present in 11.4% of the patients’ charts.

During a median follow-up of 39 months, 200 strokes occurred, including 35 in patients with depression. The incidence was 7.5% in AF patients with depression and 4.7% in those without diagnosed depression.

The depressed AF patients had more comorbid conditions, including significantly higher rates of hypertension, diabetes, chronic kidney disease, chronic obstructive pulmonary disease, obesity, cancer, and heart failure. They were also more likely to be smokers. But in a multivariate analysis controlling for comorbidities, age, gender, previous stroke, and use of anticoagulant therapy, the depressed AF patients remained at 45% greater risk of stroke compared with AF patients without diagnosed depression.

Strengths of this study include its large size and reasonable duration of follow-up. Limitations include the fact that investigators had to rely upon physician documentation of depressive episodes in the medical record, with no standardized measure of depression severity. Clinical trials addressing the issue of whether effective antidepressant therapy prevents strokes in depressed AF patients will need to use systematic screening for depression and serial measurements of depression severity, according to Dr. Lima.

He reported having no financial conflicts of interest regarding this study, which was conducted free of commercial support.