Introduction: This study aimed to systematically characterize differences in sleep architecture across clinical states and age groups in bipolar disorder (BD).
Method: We recruited 178 adults diagnosed with BD I or II, followed for a mean of 482 ± 243 days. Participants wore an Oura Ring to continuously collect a 5-min sampled hypnogram. Weekly Patient Health Questionnaire (PHQ-9) and Altman Self-Rating Mania Scale (ASRM) scores defined clinical states [euthymia, depression, (hypo)mania]. Sleep variables (e.g., light sleep duration) were compared across clinical states and age groups (median split: 37 years) using Kruskal–Wallis and pairwise Mann–Whitney U-tests with bootstrapping.
Results: We collected 5,834,600 hypnogram observations: 5,550,860 during euthymia, 261,504 during depressive episodes, and 22,236 during (hypo)manic episodes. (Hypo)mania was characterized by irregular wakefulness (i.e., fragmented sleep), the shortest REM sleep (1.41 ± 0.80 h), deep sleep (0.94 ± 0.75 h), and sleep onset latency (0.21 ± 0.24 h). Depression showed the longest deep sleep (1.82 ± 0.85 h), REM sleep (1.61 ± 0.93 h), and sleep onset latency (0.26 ± 0.31 h). During (hypo)mania, older adults (> 37 years) had shorter deep sleep (0.94 ± 0.75 h) and longer light sleep (4.67 ± 1.40 h) than younger adults.
Conclusion: This study provides a deeper analysis of sleep architecture in BD, leveraging objective, continuous data collected longitudinally using wearables. Our findings show that each clinical polarity is characterized by a distinct sleep architecture, which also differs across age groups. Further investigation into sleep phases may offer insights for treatment strategies. Age-related differences in sleep architecture were also observed, which do not mirror the patterns seen in healthy individuals.
WILEY , 2025. Vol. 27, no S1, p. 53-53
The 27th Annual Conference of the International Society for Bipolar Disorders, Chiba, Japan, 17 – 19 September 2025