Real-world evidence for the use of digital cognitive behavioural therapy for insomnia within primary care. A systematic evaluation of user data

Background: The introduction of digital health applications (DiGA) in the German healthcare system has enabled scalable access to guideline-recommended treatment for chronic insomnia. Since October 2020, the DiGA somnio can be prescribed by practitioners and offers digital cognitive-behavioural therapy for insomnia (CBT-I) for patients with an insomnia diagnosis. The availability of user data now enables us to investigate the effects of digital CBT-I as part of its use in standard care for the first time. Objectives: Analysis of user data derived from the digital CBT-I intervention somnio will provide a more comprehensive understanding of its impact, benefits, and acceptability within primary care. Materials and methods: We analysed data from N=5000 randomly selected users who completed somnio between 2021 and 2022 and reported an insomnia severity index (ISI) >= 8 at the start of the intervention. Insomnia severity (ISI) and sleep behaviour were evaluated descriptively over the course of the digital intervention. Cohen's d for within-group changes were calculated to provide information on effect measures. Results: Our analysis revealed a reduction in insomnia severity of -8.49 +/- 5.39 points on the ISI between start and end of the program (d=1.58). At completion, 57% met response criteria (reduction >= 8 points on the ISI) and 38% met criteria for remission (ISI<8). Evaluation of diary entries showed large improvement in sleep continuity and quality over time (ds=0.68-1.07). Discussion: Consistent with controlled studies, our real-world data suggests that digital CBT-I can yield clinically meaningful improvements in sleep and insomnia severity. The results support the implementation of digital therapeutics within primary care.