Sleep maintenance difficulties in insomnia are associated with increased incidence of hypertension

Study objectivesWe examined the relative contributions of sleep onset and sleep maintenance difficulties in insomnia as predictors of incidence and development of hypertension.DesignThis study is cross-sectional and longitudinal.ParticipantsThere were 967 adults with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition–based current insomnia.Measurements and resultsAt baseline, participants were divided into 2 groups based on current diagnosis of hypertension. Prevalence of hypertension in this sample was 34.7%, which is higher than the prevalence in the general population previously documented at approximately 28%. Participants completed a follow-up assessment 1 year later that revealed a 5.4% incidence of hypertension. Analyses revealed that increases in sleep maintenance difficulties, not sleep initiation difficulties, between baseline and follow-up significantly predicted increased risk for incidence of hypertension. Analyses at baseline also revealed that sleep maintenance rather than sleep initiation difficulties marginally predicted increased severity of hypertension. Results suggest that risk for hypertension may be conferred through disruptions to blood pressure with nightly repeated or prolonged awakenings.ConclusionsThis study provides novel information regarding the risk of hypertension in insomnia via sleep maintenance difficulties. Findings from this study provide preliminary evidence for examining nighttime fluctuations of blood pressure and concomitant physiological changes (ie, catecholamines, heart rate, and sympathetic activation) due to wake during sleep as a mechanism for subsequent hypertension.