RESUMO
OBJECTIVE: This randomized comparative effectiveness trial evaluated a novel insomnia treatment using acceptance and commitment therapy (ACT) among women veterans. Participants received either the acceptance and the behavioral changes to treat insomnia (ABC-I) or cognitive behavioral therapy for insomnia (CBT-I). The primary objectives were to determine whether ABC-I was noninferior to CBT-I in improving sleep and to test whether ABC-I resulted in higher treatment completion and adherence versus CBT-I. METHOD: One hundred forty-nine women veterans with insomnia disorder (Mage = 48.0 years) received ABC-I or CBT-I. The main sleep outcomes were Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), and sleep efficiency (SE) by actigraphy (objective) and sleep diary (subjective). Measures were collected at baseline, immediate posttreatment, and 3-month posttreatment follow-up. Treatment completion and adherence were assessed during the interventions. RESULTS: Both interventions improved all sleep outcomes from baseline to immediate posttreatment and 3-month posttreatment follow-up. At immediate posttreatment, ABC-I was statically noninferior for sleep diary SE and objective SE, but noninferiority was not statistically confirmed for ISI or PSQI total scores. At 3-month posttreatment follow-up, ABC-I was noninferior for all four of the key outcome variables. There was not a statistically significant difference between the number of participants who discontinued CBT-I (11%) versus ABC-I (18%; p = .248) before completing treatment. ABC-I was superior to CBT-I for some adherence metrics. CONCLUSIONS: Overall, ABC-I was similar in effectiveness compared to CBT-I for the treatment of insomnia and may improve adherence to some behavioral elements of treatment. (PsycInfo Database Record (c) 2023 APA, all rights reserved).