Abstract
Introduction
Cognitive behavioral therapy for insomnia (CBT-I) is efficacious, but there is mixed evidence as to whether improvement is blunted in adults with insomnia and short sleep duration. Exercise training can reduce physiologic hyperarousal and may increase homeostatic sleep drive, which could potentiate CBT-I treatment effects. This pilot study explored changes in self-reported outcomes from a CBT-I intervention augmented by exercise training in a sample of adults with insomnia and objective short sleep duration.
Methods
Eight adults (50% female, 62.5% white) with insomnia disorder and short sleep duration (mean actigraphic TST <6.5 hr) completed a 12-week single-arm trial. Participants self-administered the online “Sleep Healthy Using the Internet” (SHUT-I) CBT-I program with additional staff guidance while completing a supervised exercise program (EX; 150 min/wk of moderate-intensity aerobic exercise and 2 days/wk of strength training). Participants completed assessments of self-reported sleep and daytime function pre- and post-intervention, including the Insomnia Severity Index (ISI), Flinders Fatigue Scale (FFS), Ford Insomnia Response to Stress Test (FIRST), Perceived Stress Scale (PSS), and Epworth Sleepiness Scale (ESS). Differences between timepoints were analyzed using paired t-tests and Cohen’s d effect size calculations.
Results
Insomnia severity significantly decreased after the intervention (ISI: p<0.001, d=2.99), with 75% reporting post-intervention ISI ≤ 7. Likewise, fatigue significantly decreased after the intervention (FFS: p=0.032, d=0.95). Symptoms of stress-related sleep reactivity and stress were also reduced (FIRST: p=0.012, d=1.19; PSS: p=0.014, d=1.14). Though nonsignificant, large reductions in sleepiness were additionally observed (ESS: p=0.058, d=0.80).
Conclusion
In this pilot trial among patients with insomnia and short sleep duration, online CBT-I plus a supervised exercise program resulted in a significant reduction in insomnia severity. The intervention also produced large and meaningful reductions in fatigue and stress, which are common daytime impairments in patients with insomnia. Future research should attempt to disentangle the independent contributions of CBT-I and exercise on outcomes in this population.
Support (if any)
NIH: K23HL118318
Objective short sleep duration and its effect on 24-hour blood pressure
