Attenuated clinical response to intensive outpatient treatment for evening chronotypes among acutely suicidal adolescents

Abstract Study Objectives Evening chronotypes (“night owls”) are vulnerable to depression and suicidal thoughts and behaviors. Evening chronotype may be an underrecognized factor contributing to treatment response in high acuity settings. The present study examined chronotype in a sample of acutely suicidal adolescents receiving intensive outpatient treatment. Materials and Methods Adolescents (N = 179, ages 13–18, 80% White, 77% female sex at birth) were enrolled in an intensive outpatient treatment program for depressed and suicidal youth and followed for up to 2 months. Clinicians rated weekly depression severity and suicidal ideation (SI) using the A-LIFE Psychiatric Severity Rating scales, and participants completed monthly questionnaires including the Composite Scale of Morningness. Multilevel models examined longitudinal associations between changes in chronotype and depression/SI, and whether shifts in chronotype moderated changes in depression/SI over time. Results Depression and suicidal ideation improved throughout treatment. Sleep onset timing did not change significantly. While overall chronotype did not change across treatment, within-person shifts towards eveningness were associated with more persistent clinician-rated depression and suicidal ideation throughout treatment. Shifts in chronotype moderated improvement in depression during treatment: shifts towards eveningness showed a slower rate of improvement over time while shifts towards morningness showed a faster improvement in depression over time. Conclusions Shifting to a more evening chronotype was associated with a slower clinical response to intensive outpatient treatment for depression, suggesting possible underemphasized treatment targets in intensive outpatient treatment. Interventions shifting evening chronotype and sleep timing earlier, including timed light and behavioral sleep interventions, may be clinically indicated in higher levels of care. This paper is part of the Sleep and Circadian Mechanisms in Mental Health Collection.