Abstract MP71: Short Sleep Duration Modifies the Relationship Between Hypertension and All-Cause Mortality
Introduction: Short sleep duration has been associated with increased risk of hypertension and mortality. However, previous epidemiological studies have been limited in that they used self-reported sleep measures and treated sleep duration as a sole, independent predictor of cardiometabolic morbidity or mortality. Therefore, the role of sleep duration in predicting morbidity and mortality is still not well-understood. Our current research project examines the role of objective sleep duration as an effect modifier between traditional cardiometabolic risk factors and mortality.
Hypothesis: We assessed the hypothesis that objectively-measured sleep duration is a key effect modifier of the relationship between hypertension and all-cause mortality.
Methods: We addressed this question in the Penn State Adult Cohort, a random, general population sample of 1,741 men and women (48.7 ± 13.5 years) who were studied in the sleep laboratory and were followed-up for 15.5 ± 4.1 years. Hypertension was defined as systolic blood pressure ≥ 90mmHg / diastolic blood pressure ≥ 140mmHg or use of antihypertensive medication. Polysomnographic sleep duration was classified into three categories: ≥ 6 hours (i.e., ≥ 50th percentile), 5-6 hours (i.e., 25-50th percentile), and ≤ 5 hours (i.e., ≤ 25th percentile). We tested the interaction between hypertension and objective sleep duration on all-cause mortality using multiple logistic regression, while controlling for sex, age, race, obesity, diabetes, history of heart disease and stroke, smoking, depression, insomnia, and sleep apnea.
Results: The mortality rate was 19.6%. The multivariable-adjusted odds ratio (OR) of all-cause mortality associated with hypertension was 2.54 (95% CI: 1.81-3.56). The multivariable-adjusted ORs associating hypertension and all-cause mortality were 1.75 (95% CI: 1.01-3.02), 2.36 (95% CI: 1.15-4.83), and 4.04 (95% CI: 2.22-7.38) for individuals with ≥ 6 hours, 5-6 hours, and ≤ 5 hours of sleep, respectively (p-value for interaction = .03).
Conclusion: We found that objective sleep duration modifies the relationship between hypertension and all-cause mortality in a dose-response manner, with the largest magnitude of association observed in those who slept ≤ 5 hours. Short sleep duration in hypertensive individuals may be biologically driven, behaviorally induced, or a marker of the severity of the degree of autonomic dysfunction. Further analyses will examine this effect modification using cause-specific mortality data and future studies should examine whether improving/lengthening sleep reduces the odds of mortality in individuals with hypertension.
Author Disclosures: J. Fernandez-Mendoza: None. F. He: None. A. Vgontzas: None. D. Liao: None. E. Bixler: None.
This research has received full or partial funding support from the American Heart Association, National Center.
- © 2015 by American Heart Association, Inc.