Chronotherapeutic interventions have been proposed as non-pharmacological strategies for the rapid modulation of depressive symptoms in bipolar disorder. Total sleep deprivation (TSD) may induce short-term mood improvements, and morning bright light therapy (BLT) has been suggested to help stabilize these effects. However, the impact of these interventions on service-level outcomes, including length of hospital stay (LOS), has not been systematically evaluated. We analyzed two non-overlapping retrospective cohorts (1994-1998 and 2015-2024) from the same Mood Disorders Unit, including adults hospitalized for a bipolar depressive episode. Within each cohort, patients received either treatment as usual (TAU) or TAU with chronotherapy, consisting of TSD in the earlier cohort and TSD with morning BLT in the later one. LOS was examined with general linear models adjusted for age and sex. The combined sample included 1241 admissions (706 from 1994-1998; 535 from 2015-2024). In both cohorts, LOS was shorter with TSD than with TAU (1994-1998: 20.99±11.09 days vs 23.23±13.34, F = 5.31, p = 0.02; 2015-2024: 24.00±8.24 vs 27.62±8.67, F = 15.46, p < 0.01), with a small effect size in the earlier cohort (d = 0.176) and a small-to-moderate effect in the later one (d = 0.425). Treatment × Cohort interaction was not significant (F = 0.55, p = 0.46). Across three decades, the use of chronotherapy was consistently associated with shorter LOS in bipolar depression, despite major changes in clinical practice, organizational structure, and environmental circadian stressors. While causality cannot be inferred due to the observational design, these findings suggest that TSD-based chronotherapeutic interventions may represent a promising approach within acute inpatient care pathways, potentially contributing to improved hospitalization trajectories and discharge readiness in bipolar depression.

Childhood maltreatment and FKBP5 CATT haplotypes increase identity dissociation risk. While maltreatment often fosters disorganized attachment, the specific role of the FKBP5 CATT haplotype within this developmental pathway remains unknown. In 310 trauma-exposed adults, we assessed childhood maltreatment, disorganized attachment, and identity dissociation. FKBP5 CATT haplotype status was dichotomized (present/absent). Regression models were estimated to examine the pathway Childhood Maltreatment → Disorganized Attachment → Identity Dissociation, comparing two competing hypotheses: 1) The Formation Hypothesis (Maltreatment × CATT → Disorganization), and 2) The Translation Hypothesis (Disorganization × CATT → Identity Dissociation). Model fit was compared using BIC, and simple slopes were examined. Disorganized attachment predicted identity dissociation (β = 0.143, z = 3.83, p < .001), and childhood maltreatment predicted disorganization (β = 0.007, z = 4.46, p < .001). The Formation hypothesis was not supported, as the Maltreatment × CATT interaction did not predict disorganization (β = -0.004, z = -1.18, p = .24). However, the Translation hypothesis was supported by three pieces of evidence: a significant Disorganization × CATT interaction predicting identity dissociation (β = 0.133, z = 2.22, p = .027), model fit (∆BIC = 265.3), and simple slopes showing a strong effect of disorganization on identity dissociation for CATT carriers (β = 0.15, p < .001; +16.5 % per unit) but not for non-carriers (β = 0.02, p = .65). The FKBP5 CATT haplotype does not promote disorganized attachment but amplifies the translation of disorganized attachment into identity dissociation. This result highlights a genetically influenced failure of identity development following disorganized attachment.