A secondary analysis published in the journal Behaviour Research and Therapy [1] based on a randomised controlled trial (RCT) [2] shows that the digital insomnia therapy somnovia achieves its clinical effects primarily through the reduction of hyperarousal, a key transdiagnostic process that plays a role in sleep disorders as well as depressive and anxiety symptoms. The findings are particularly relevant given the ongoing under-treatment of adults with chronic insomnia in Germany [3] and elucidate the mechanism underlying somnovia's broader effects on mental health that extend beyond sleep disorders alone.
The analysis includes data from 290 adults with chronic insomnia from a previously published RCT demonstrating the efficacy of somnovia2. In that trial, participants were randomised to receive either somnovia in addition to treatment as usual (TAU) or TAU alone. Using Network Intervention Analysis (NIA), a statistical method for symptom-specific effects, the researchers investigated which individual symptoms of insomnia, depression and anxiety are most directly influenced by somnovia and how these changes propagate through the symptom network. After three months, the direct effects primarily concerned hyperarousal-related symptoms: difficulty relaxing, dissatisfaction with sleep quality, sleep-related worries and psychomotor agitation. After six months, the effects were more widely distributed across the symptom network and also extended to depressive and anxiety symptoms.
Dr. Linda Betz, lead author of the study and researcher in GAIA's Research and Development department, says: "Network Intervention Analysis allows us to take a much more nuanced look at the mechanisms of action of digital therapies than the usual evaluation of total scores permits. Our results show that somnovia primarily targets a central transdiagnostic process: hyperarousal. Because this process is linked to numerous other mental health conditions, this suggests that the positive effects can extend beyond the mere sleep problem to include symptoms of depression and anxiety."
somnovia is a fully self-guided, web-based digital therapy for adults with chronic insomnia. The programme implements the core components of cognitive behavioural therapy for insomnia (CBT-I), including sleep restriction, stimulus control, sleep hygiene, relaxation and mindfulness techniques, as well as cognitive techniques for addressing dysfunctional sleep-related thoughts. The therapeutic content is delivered in a conversational format and supplemented by audio-guided relaxation and meditation exercises, as well as reminder functions.
Chronic insomnia affects around 6% of adults in Germany; approximately 20% report at least some impairment in sleep quality [4] . If left untreated, it is associated with significant reductions in quality of life and everyday functioning. At the same time, it is both a risk factor and a common accompanying symptom of other mental health conditions, particularly depression and anxiety disorders, making insomnia a key transdiagnostic treatment target. The German S3-guideline recommends CBT-I as first-line treatment; digital CBT-I achieves comparable efficacy to face-to-face treatment in meta-analyses [5] . In clinical practice, however, face-to-face CBT-I is scarcely available in many places due to limited therapy places, long waiting times and a lack of specialisation, leading to a persistent gap in care for those affected.
somnovia is permanently listed in the German "DiGA directory" of the Federal Institute for Drugs and Medical Devices (BfArM) as a digital health application. This means that the therapeutic programme can be prescribed in Germany by doctors and psychotherapists. The costs are covered by all statutory health insurance funds.
[1] Betz, L. T., Göder, R., Jacob, G. A., & Riemann, D. (2026). Targeting hyperarousal to improve sleep: A network intervention analysis of a digital intervention for insomnia. Behaviour Research and Therapy, 203, 105075. https://doi.org/10.1016/j.brat.2026.105075
[2] Specht, A., Betz, L. T., Riepenhausen, A., Jauch‐Chara, K., Jacob, G. A., Riemann, D., & Göder, R. (2024). Effectiveness and safety of an interactive internet‐based intervention to improve insomnia: Results from a randomised controlled trial. Journal of Sleep Research, e14409. https://doi.org/10.1111/jsr.14409
[3] Heidbreder, A., Kunz, D., Young, P., Benes, H., Chalet, F.-X., Vaillant, C., Kaskel, P., Fietze, I., & Schöbel, C. (2024). Insomnia in Germany—Massively inadequate care? Somnologie. https://doi.org/10.1007/s11818-024-00460-9
[4] Schlack, R., Hapke, U., Maske, U., Busch, M., & Cohrs, S. (2013). Frequency and distribution of sleep problems and insomnia in the adult population in Germany. Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz. https://doi.org/10.25646/1464
[5] Simon, L., Steinmetz, L., Feige, B., Benz, F., Spiegelhalder, K., & Baumeister, H. (2023). Comparative efficacy of onsite, digital, and other settings for cognitive behavioral therapy for insomnia: A systematic review and network meta-analysis. Scientific Reports, 13(1), Article 1. https://doi.org/10.1038/s41598-023-28853-0
