Abstract W MP72: Sleep and Timing of Recurrent Events in a Mild Stroke Population: Results of the SWIFT Study

Abstract

Sleep is an important contributor to cardiovascular disease; we have previously reported it is a risk factor for incident vascular events. It is thought that sleep apena may be the primary mechanism through which sleep disturbance is associated with vascular events. Little is known, however, about the association between sleep and recurrent events. The aim of this analysis was to determine the association between sleep problems and the risk of recurrent vascular events in an elderly, multiethnic population. This analysis uses data from SWIFT, a randomized clinical trial conducted in northern Manhattan designed to test a stroke preparedness intervention. Sleep was measured with the MOS sleep scale. MOS is a 12 item questionnaire that produces 8 validated scales. We report results using the snoring (1 question), shortness of breath during sleep (1 question), and sleep problem index 2 (9 questions) scales. Outcomes were collected prospectively through active surveillance. We used Cox Models to test whether our measures of sleep were associated with an increased hazard of having a recurrent event. SWIFT randomized 1193 stroke participants: mean age 63 years +- 15.14; 50% female; 17% black, 51% Hispanic, 26% white, 6% other. In models adjusted for treatment assignment, race, age, gender, education, marital status and baseline measures of hypertension, diabetes, smoking and NIH stroke scale the sleep problems index 2 was associated with an increased hazard of a first recurrent stroke or TIA (HR=1.91, p-value=0.02), whereas our measures of snoring (HR=1.20, p-value=0.43) and shortness of breath during sleep (HR=1.39, p-value=0.46) were not. The same pattern of results held for a composite measure of first recurrent stroke, TIA, MI or vascular death: sleep problems index 2 (HR=1.97, p-value=0.003), snoring (HR=1.10, p-value=0.62) and shortness of breath during sleep (HR=1.59, p-value=0.18). Our results highlight the contribution of sleep to the risk of recurrent vascular events in a population of mild and moderate stroke/TIA survivors. Importantly, this result is not driven by snoring or trouble breathing at night and is independent of hypertension, smoking and diabetes.