[[DP - Sleep]] [[Depression]] # Wearables as relapse biomarkers (depression): actigraphy markers predict relapse over 1–2 years https://pubmed.ncbi.nlm.nih.gov/41670991/ A longitudinal JAMA Psychiatry study operationalized relapse using clinical escalation endpoints (MADRS 22 for 2 weeks, hospitalization, suicidal intent/behavior, or antidepressant escalation) and linked relapse risk to sleep/activity regularity features from continuous actigraphy. [PubMed abstract](https://pubmed.ncbi.nlm.nih.gov/41670991/) reports that lower sleep regularity, lower relative amplitude (day–night activity contrast), lower sleep efficiency, and higher wake after sleep onset / nighttime activity were associated with relapse. Why it matters for HOPES: Reinforces sleep/activity rhythm features as plausible “early warning” signals and supports building dashboard-facing metrics (e.g., relative amplitude, regularity) that can trigger clinician review. Source: [https://pubmed.ncbi.nlm.nih.gov/41670991/](https://pubmed.ncbi.nlm.nih.gov/41670991/) --- # What the study found: A large, long-term study (JAMA Psychiatry) tracked people with depression using wearables (actigraphy = movement/sleep sensors) over 1–2 years. It found that certain sleep and activity patterns could predict whether someone would relapse. Specifically, people who relapsed tended to show: - Irregular sleep — inconsistent sleep/wake timing - Low relative amplitude — their days and nights looked similar (less active by day, more restless at night — blurred contrast) - Poor sleep efficiency — more time in bed, less actual sleep - High WASO — waking up a lot during the night How they defined "relapse": Not just self-report — they used hard clinical endpoints: MADRS score ≥22 for 2 weeks, hospitalization, suicidal behavior, or medication escalation.