Abstract: Objective To investigate the effect of digital cognitive behavioral therapy for insomnia (dCBT-I) on sleep quality and cognitive function in the elderly patients with depression and insomnia. Methods A total of 43 elderly patients with depression and insomnia treated in Jiangsu Province Official Hospital from October 2021 to June 2023 were enrolled, including 20 patients with early-onset depression (EOD group) and 23 patients with late-onset depression (LOD group). All patients received dCBT-I for 6 weeks, and their cognitive function and subjective and Objective sleep quality were evaluated before and after treatment. Results After dCBT-I intervention, the scores of 17-item Hamilton Depression Rating Scale (HAMD-17) in the two groups were reduced significantly (P<0.05). The number of delayed recall words in the auditory verbal learning test (AVLT) in LOD group was significantly more than that before intervention, and the scores of clock Drawing test (CDT) and trail making test (TMT) were significantly better than those before intervention (P<0.05). AVLT delayed recall was significantly improved in EOD group, but other cognitive metrics showed no significant changes. Pittsburgh Sleep Quality Index (PSQI) score, prolonged total sleep time, enhanced sleep efficiency, and the proportion of non-rapid eye movement sleep stage 3 were significantly increased in the two groups. Conclusions dCBT-I can effectively alleviate depressive symptoms, improving sleep quality and specific cognitive functions in the elderly patients with depression, especially enhancing delayed recall and executive function in LOD patients.

Key words: early-onset depression, late-onset depression, digital cognitive behavioral therapy for insomnia, insomnia