Study objectives: To compare the efficacy of cognitive behavioral therapy for insomnia (CBTi) disorder and a Control condition on reducing insomnia and comorbid symptoms in a sample of active duty military personnel.
Methods: Randomized clinical trial of 151 active duty US Army personnel at Fort Hood, Texas.
Results: This study replicated Original (n = 66) findings (CBTi outperformed Control) in a follow-on sample (n = 85) on diary-assessed sleep efficiency (d = 1.04), total sleep time (d = 0.38), sleep latency (d = -0.93), number of awakenings (d = -0.56), wake time after sleep onset (d = -0.91), sleep quality (d = 1.00), and the Insomnia Severity Index (d = -1.36) in active duty soldiers. CBTi also outperformed Control in the combined sample (N = 151) on four of the five subscales of the Multidimensional Fatigue Inventory (d = -0.32 to -0.96) and the mental health subscale on the Veterans RAND 12-Item Health Survey (d = 0.37). Exploratory analyses also showed CBTi outperformed Control on nicotine (d = -0.22) and caffeine (d = -0.47) use reduction. Significant within-group differences were found for both groups on depression, anxiety, and posttraumatic stress disorder symptoms, but there was no group by time interaction for these symptoms or for use of hypnotics or alcohol.
Conclusions: CBTi was an effective treatment for insomnia and comorbid symptoms including daytime fatigue, general mental health, nicotine, and caffeine use.
Clinical trial registration: Clinicaltrials.gov; Identifier: NCT01549899; "Comparing Internet and In-Person Brief Cognitive Behavioral Therapy of Insomnia".