Is Sleep Apnea a Risk Factor for Strokes?

Introduction: Previous studies have suggested that the obstructive sleep apnea syndrome may be an important risk factor for stroke. It has not been determined, however, whether the syndrome is independently related to the risk of stroke or death from any cause after adjustment for other risk factors, including hypertension.

Study Objective: Stroke is the second leading cause of death worldwide and the leading cause of long-term disability. Strategies for stroke prevention, including the control of hypertension, treatment of atrial fibrillation, and smoking cessation, have reduced the disease burden, but stroke still remains an important public health challenge. A better understanding of the risk factors for stroke is needed to develop additional preventive strategies.

The obstructive sleep apnea syndrome is a treatable form of disordered breathing in which the upper airway closes repeatedly during sleep. The syndrome is associated with vascular risk factors and with substantial cardiovascular morbidity and mortality. Several studies have shown a prevalence of the syndrome among patients with stroke that exceeds 60 percent,4-7 as compared with 4 percent in the middle-aged adult population.

Previous studies have suggested that the obstructive sleep apnea syndrome may be an important risk factor for stroke. It has not been determined, however, whether the syndrome is independently related to the risk of stroke or death from any cause after adjustment for other risk factors, including hypertension.

Study Conclusions: The obstructive sleep apnea syndrome significantly increases the risk of stroke or death from any cause, and the increase is independent of other risk factors, including hypertension.

Publisher: The New England Journal of Medicine, 353;19, November 10, 2005