Insomnia severity during early abstinence is related to substance use treatment completion in adults enrolled in an intensive outpatient program

Background: Insomnia and other types of sleep disturbance are highly prevalent during withdrawal across many different types of substance use disorders (SUDs). It is largely unknown how sleep impacts SUD treatment outcomes, including treatment completion. Methods: A retrospective chart review was conducted to obtain information about sleep disturbance and treatment completion in individuals beginning an intensive outpatient (IOP) SUD treatment program. Demographic data were collected along with number of sessions completed, treatment completion, comorbid psychiatric diagnosis, pertinent lab results, and scores on three self-reported measures of sleep: the Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), and Epworth Sleepiness Scale (ESS). Results: Pertinent information was available for 110 individuals. The majority had clinically significant scores on the ISI and PSQI but not the ESS. ISI, but not PSQI or ESS, was associated with treatment completion, such that those with more insomnia were less likely to complete treatment. Conclusion: The high prevalence of insomnia symptoms and poor sleep quality coupled with the relationship between insomnia severity and treatment completion may indicate that more severe symptoms of insomnia are a risk factor for treatment completion and subsequent relapse across many substance types. Applying evidence-based insomnia interventions in SUD treatment programs may have meaningful implications for outcomes.