Study objectives: The association of sleep-disordered breathing (SDB) and blunting of normal nocturnal lowering of blood pressure (BP) (nondipping) has only been examined cross-sectionally. The purpose of this study is to investigate whether SDB is prospectively associated with nondipping.
Methods: The longitudinal association between SDB and incident nondipping was examined in a subsample of 328 adults enrolled in the Wisconsin Sleep Cohort Study who completed 2 or more 24-hour ambulatory BP studies over an average of 7.2 years of follow-up. SDB identified by baseline in-laboratory polysomnography was defined by apnea-hypopnea index (AHI) categories. Systolic and diastolic nondipping was defined by systolic and diastolic sleep-wake BP ratios > 0.9. All models were adjusted for age, sex, body mass index at baseline and follow-up, smoking, alcohol consumption, hypertension, sleep time, length of follow-up time, and antihypertensive medication use.
Results: There was a dose-response increased odds of developing systolic nondipping in participants with SDB. The adjusted odds ratios (95% confidence interval) of incident systolic nondipping for baseline AHI 5 to < 15 and AHI ≥ 15, versus AHI
Conclusions: Our longitudinal findings of a dose-response increase in development of systolic nondipping of BP with severity of SDB at baseline in a population-based sample provide evidence consistent with a causal link. Nocturnal systolic nondipping may be a mechanism by which SDB contributes to increased cardiovascular disease.
Original Publication Citation
Hla, K. M., Young, T., Finn, L., Peppard, P. E., Szklo-Coxe, M., & Stubbs, M. (2008). Longitudinal association of sleep-disordered breathing and nondipping of nocturnal blood pressure in the Wisconsin Sleep Cohort Study. Sleep, 31(6), 795-800.
Hla, Khin Mae; Young, Terry; Finn, Laurel; Peppard, Paul E.; Szklo-Coxe, Mariana; and Stubbs, Maryan, "Longitudinal Association of Sleep-Disordered Breathing and Nondipping of Nocturnal Blood Pressure in the Wisconsin Sleep Cohort Study" (2008). Community & Environmental Health Faculty Publications. 69.