Clinical feasibility of cognitive behavioural therapy for insomnia in a real-world mixed sample at a specialized psychiatric outpatient clinic

BACKGROUND: A majority of psychiatric patients suffer from insomnia or insomnia-like problems. In addition to impairing quality of life, sleep problems can worsen psychiatric conditions, such as depression and anxiety, and can make treatment of various psychiatric conditions less successful. Several international guidelines recommend cognitive behavioural therapy for insomnia (CBT-I) as first line treatment. However, patients in psychiatric care are rarely offered this treatment, and there is a lack of studies evaluating the treatment in regular psychiatric settings. In this pilot study, we aimed to determine the clinical feasibility of a group-based CBT-I intervention in an outpatient clinical setting for patients with depression, bipolar disorder, anxiety disorders and PTSD. We also aimed to investigate if symptoms of insomnia, depression and anxiety changed after CBT-I. METHODS: Seventeen patients at an out-patient psychiatric clinic for mixed psychiatric problems of anxiety, affective disorders and PTSD, were enrolled in a six-week long group-based CBT-I intervention. Primary outcomes were pre-defined aspects of treatment feasibility. Secondary outcomes were changes in self-reported symptoms of insomnia severity, depression, and anxiety between pre – and post intervention. Assessment of insomnia severity was also performed 3 months after treatment. Feasibility data is reported descriptively, changes in continuous data from pre- to post-treatment were analysed with dependent t-tests. RESULTS: All feasibility criteria were met; there were enough patients to sustain at least one group per semester (e.g., minimum 8), 88% of included patients attended the first session, mean of attended sessions was 4.9 of 6, and drop-out rate was 5.9%. Therapists, recruited from clinical staff, found the treatment manual credible, and possible to use at the clinic. Symptoms of insomnia decreased after treatment, as well as symptoms of depression and anxiety. CONCLUSION: CBT-I could prove as a clinically feasible treatment option for insomnia in a psychiatric outpatient setting. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT05379244. Retrospectively registered 18/05/2022.