Effects of remotely-delivered cognitive behavioral therapy for insomnia in type 2 diabetes: a randomized controlled trial

Abstract Purpose To evaluate the effects of remotely delivered cognitive behavioral therapy for insomnia (CBTI) on subjective sleep quality, glycemic control, and objective sleep parameters in individuals with type 2 diabetes (T2D) and insomnia. Methods Forty adults with non-insulin-treated T2D and insomnia were randomized to CBTI ( n = 20) or health education (HE, n = 20), delivered weekly via one-hour online sessions for eight weeks. The primary outcome was self-reported sleep quality (Pittsburgh Sleep Quality Index, PSQI). Secondary outcomes included actigraphy-based sleep measures, glycemic control (A1C, fasting glucose), insomnia symptoms, anxiety, depression, and quality of Life. Data were collected at baseline, week 8, and week 16. Mixed-effects linear regression was used to assess between-group differences. Results At week 8, no significant difference in PSQI was observed between groups, but the CBTI group showed improved actigraphy-based sleep regularity (variation of sleep duration), mean difference − 21.84 min (95% CI -41.64, -2.05; P = 0.031). At week 16, CBTI led to a greater reduction in anxiety symptoms ( P = 0.039). There were no differences in other outcomes. In per-protocol analysis (CBTI: n = 15; HE: n = 10), CBTI resulted in improved subjective sleep quality ( P = 0.042), sleep regularity ( P = 0.018) and fasting glucose at week 8 (mean difference − 34.27 mg/dL; 95% CI -55.16, -13.37; P = 0.001). Satisfaction was high in both groups. Conclusion CBTI improved sleep regularity and anxiety in T2D patients with insomnia. Adherence to CBTI also led to fasting glucose reductions, supporting its role in glycemic management. Sleep-focused interventions like CBTI should be integrated into care for T2D with insomnia to optimize sleep and metabolic outcomes.