# The Transdiagnostic Intervention for Sleep and Circadian Dysfunction (TSC) in Community Mental Health: Evaluating Self-Reported Psychiatric Disorders as a Predictor of Symptoms and Treatment Outcome

## TL;DR

This study examines how self-reported psychiatric disorders affect treatment outcomes for a sleep and circadian dysfunction intervention in patients with serious mental illness.

## Contribution

The study shows that the number of psychiatric disorders predicts baseline symptom severity but not treatment response to a transdiagnostic sleep intervention.

## Key findings

- Patients with more psychiatric disorders had worse baseline sleep and psychiatric symptoms.
- Psychiatric disorder count did not predict treatment outcomes or differences between Standard and Adapted TSC.
- Immediate TSC led to greater improvement in sleep disturbance and impairment compared to delayed treatment.

## Abstract

This study investigated the extent to which self-reported psychiatric disorders and comorbidities in patients receiving the Transdiagnostic Intervention for Sleep and Circadian Dysfunction (TSC) predicted symptom/impairment severity and treatment outcome.

This secondary analysis drew from a subset of 489 patients in California-based Community Mental Health Centers with serious mental illness (SMI) and sleep/circadian problems who had participated in a randomized controlled trial of TSC. Of these patients, 253 received Immediate TSC and 236 received usual care followed by delayed treatment (UC-DT). Some patients received Standard TSC (N=149) while others received Adapted TSC (N=340). We analyzed patients’ baseline/pre-treatment and post-treatment scores for psychiatric symptoms, sleep disturbance, sleep-related impairment, overall sleep health, and functional impairment. We also used patient-reported data on history of psychiatric diagnoses.

At baseline, patients with more disorders had worse psychiatric symptom scores (b=2.27, SE=0.39, p<.001), greater sleep disturbance prior to eliminating outliers (b=0.71, SE=0.31, p=.023), greater sleep-related impairment (b=1.25, SE=0.34, p<.001), worse overall sleep health (b=−0.20, SE=0.06, p=.001), and greater functional impairment (b=0.32, SE=0.11, p=.005). Number of psychiatric disorders was not associated with treatment outcome or differences in benefits between Standard and Adapted TSC. When analyzed independently, the most common psychiatric disorder groups all demonstrated significantly more improvement in the Immediate TSC group than in the UC-DT group on sleep disturbance and sleep-related impairment.

These results build on strong evidence that transdiagnostic sleep treatment is an important approach to treating populations with comorbid SMI and sleep/circadian problems. This secondary analysis was not pre-registered but uses data from primary analyses that were pre-registered on clinicaltrials.gov (phase 1/generation 1: https://clinicaltrials.gov/study/NCT04154631; phase 2/generation 2: https://clinicaltrials.gov/study/NCT05805657).