Cognitive-behavioral therapy for insomnia (CBT-I) shows treatment benefits among individuals with pain interference; however, effects of Internet-delivered CBT-I for this population are unknown. This secondary analysis used randomized clinical trial data from adults assigned to Internet-delivered CBT-I to compare changes in sleep by pre-intervention pain interference. Participants (N = 151) completed the Insomnia Severity Index (ISI) and sleep diaries [sleep onset latency (SOL); wake after sleep onset (WASO)] at baseline, post-assessment, 6- and 12-month follow-ups. Linear mixed-effects models showed no differences between pain interference groups (no, some, moderate/severe) for changes from baseline to any follow-up timepoint for ISI (p = .72) or WASO (p = .88). There was a small difference in SOL between those reporting some versus no or moderate/severe pain interference (p = .04). Predominantly comparable and sustained treatment benefits for both those with and without pain interference suggest that Internet-delivered CBT-I is promising for delivering accessible care to individuals with comorbid pain and insomnia.
Keywords: Cognitive behavioral therapy; Comorbidity; Insomnia; Internet; Pain interference.