Actigraphy-Assessed Sleep Efficiency is Associated with Ambulatory Blood Pressure in a Community Sample

Abstract

Objective: Epidemiological data increasingly supports sleep as a determinant of cardiovascular disease risk. Fewer studies have investigated the mechanisms underlying this relationship or employed objective sleep assessment approaches to discern the CVD impact of specific sleep characteristics. The aim of this study was to examine associations between objectively assessed sleep duration and efficiency and daily blood pressure as a potential atherogenic pathway. Methods: A diverse community sample of 300 men and women ages 21-70, enrolled in the North Texas Heart Study participated in the study. Actigraphy assessed sleep was monitored over 2 consecutive nights with ambulatory blood pressure sampled randomly within 45-min blocks on the first and second day and second night. Results: Complete data was available for 216 participants. As predicted, individuals with lower mean sleep efficiency had higher daytime (systolic: B=-0.241, SE=0.100, p<.017, adjusted R2 =0.412; diastolic: B=-0.121, SE=0.06, p<.045, adjusted R2 =0.356) and nighttime BP (systolic: B= -0.696, SE=0.174, p<.001, adjusted R2 = .243; diastolic: B= -0.410, SE= 0.093, p<.001, adjusted R2 = .230). Moreover, lower sleep efficiency on one night was associated with higher systolic (B= -0.386, SE= 0.111, p<.001, adjusted R2 =0.325) but not diastolic BP (B= -0.126, SE= 0.067, p=.062, adjusted R2 = .223) the following day. Overall, sleep duration was associated with systolic BP only, with the exception of nighttime BP. Conclusions: Objectively assessed sleep efficiency and duration are associated with both concurrent nighttime BP and subsequent day BP and may serve as pathways linking sleep to CVD.