A30-08 Sleep Efficiency as Marker of Health in Obstructive Sleep Apnea: Insights From Wearable Data

Abstract Rationale Sleep efficiency, defined as the proportion of time in bed spent asleep, is a key indicator of sleep quality and recovery. Among individuals with obstructive sleep apnea (OSA), sleep efficiency may also reflect broader aspects of health behavior and autonomic balance. Leveraging large-scale wearable data, we examined differences in physical activity, sleep duration, and physiological parameters across sleep efficiency categories in adults with OSA. Methods Wearable-derived data were analyzed from 117,308 adults with OSA. Sleep efficiency was calculated as total sleep time (TST) divided by time in bed and expressed as a percentage, excluding values of 100 percent, and averaged across valid nights per participant. Participants were categorized as efficient (≥85%), moderately efficient (80 to 85%), or inefficient (80%). Daily averages were derived for TST, step count, exercise minutes, body mass index (BMI), resting heart rate (RHR), heart rate variability (HRV), and mean oxygen saturation (SpO2). Between-group differences were evaluated using Kruskal-Wallis rank-sum tests. Results Across sleep efficiency groups, all comparisons were statistically significant (p 0.001). Efficient sleepers (n = 70,509) demonstrated longer sleep duration, greater physical activity, and more favorable cardiovascular markers than moderately efficient and inefficient sleepers. Mean TST was 420.6 ± 56.6 minutes among efficient sleepers compared to 391.1 ± 58.7 minutes in inefficient sleepers. Efficient sleepers also had higher step counts (6,138 ± 2,680 vs. 5,577 ± 2,555) and daily exercise minutes (31.1 ± 29.1 vs. 26.7 ± 25.3). Resting heart rate was lower (63.5 ± 8.6 vs. 65.2 ± 8.5 bpm) and HRV slightly higher (36.0 ± 17.3 vs. 34.9 ± 19.8 ms) in the efficient group. Differences in BMI were small (32.0 ± 6.3 vs. 32.6 ± 6.7 kg/m²), while mean SpO2 was comparable across groups (95.7 ± 1.3% vs. 95.6 ± 1.3%). Conclusions In this large real-world cohort of adults with OSA, higher sleep efficiency was consistently linked with longer sleep duration, greater daily physical activity, and lower resting heart rate, an integrated pattern suggestive of more effective behavioral regulation and autonomic recovery. Collectively, the findings position sleep efficiency as a sensitive, wearable-derived indicator of sleep health and daytime resilience in OSA, bridging nighttime physiology with daytime function and offering a scalable marker for digital health monitoring and behavioral intervention. This abstract is funded by: Resmed