Severe sleep apnea and risk of ischemic stroke in the elderly.

Background and Purpose— Convincing evidence of a causal relationship between sleep apnea and stroke has been shown recently in several prospective, well-designed studies. However, these studies have focused on middle-aged people, excluding the elderly population from analysis. To investigate whether sleep apnea represents an independent risk factor in this population, we performed a prospective longitudinal study in a population-based cohort of subjects from 70 to 100 years old. Methods— Within the context of the Vitoria Sleep Project, a population-based study designed to investigate the prevalence of sleep apnea in the population of Vitoria, Spain, we performed a 6-year longitudinal study in a subsample cohort of 394 noninstitutionalized, initially event-free subjects (70 to 100 years old, median 77.28 years, 57.1% males). Demographic and polysomnographic data and known confounding factors (age, sex, smoking and alcohol consumption status, body mass index, systolic and diastolic blood pressure, total ser...