0496 Sleep-Disordered Breathing, Sleep Duration, and 24-Hour Ambulatory Blood Pressure in Self-Perceived Short-Sleeping Adults

Abstract Introduction Obstructive sleep apnea (OSA) and short sleep duration each contribute to hypertension risk, yet their combined influence on 24-hour blood pressure patterns is not well characterized. This study evaluated associations between apnea–hypopnea index (AHI), objective sleep duration, and ambulatory blood pressure (ABP), and tested whether sleep duration modifies relationships between AHI and nocturnal dipping among adults with elevated in-office blood pressure. Methods This cross-sectional analysis used baseline data from a behavioral sleep extension trial. Adults aged 18–65 years were eligible if they reported habitual sleep < 7 hours and had elevated in-office blood pressure (systolic 120–140 mmHg or diastolic 80–90 mmHg). Objective sleep was measured for seven days with a wrist-worn actigraphy device. OSA severity was assessed using a single-night home sleep apnea test generating AHI values. Participants completed 24-hour ABP monitoring, with daytime and nighttime windows aligned to actigraphy-defined rest periods. Linear regression models tested associations between AHI and mean systolic and diastolic blood pressure. Logistic models examined associations between AHI and systolic and diastolic non-dipping (< 10% nocturnal reduction). Moderation by total sleep time was evaluated with interaction terms. Adjusted models included age, sex, race, and body mass index. Results A total of 195 participants had valid actigraphy, AHI data, and ambulatory blood pressure data with a mean age of 42 ± 11 years. AHI was not associated with mean systolic blood pressure in unadjusted or adjusted models. Higher AHI was associated with higher mean diastolic blood pressure in unadjusted (p=0.013) and adjusted (p=0.045) models. AHI predicted systolic non-dipping in unadjusted analyses (p=0.049), with a marginal effect after adjustment (p=0.090). AHI was not associated with diastolic non-dipping. Sleep duration did not moderate AHI associations with mean blood pressure but longer sleep significantly attenuated the AHI–systolic non-dipping relationship (p=0.045). Conclusion Among adults with elevated in-office blood pressure and short sleep duration, greater OSA severity predicted higher mean diastolic blood pressure and increased systolic non-dipping, with longer sleep time weakening the influence of AHI on nocturnal systolic dipping. Support (if any) NIH award number R01HL141811 (PI: Baron).