Transdiagnostic cognitive behavioral therapy for severe and persistent fatigue – a feasibility study in primary care

Abstract Background Fatigue is the main complaint of 5–10% of patients in primary care and is often associated with significant suffering and functional disability. Cognitive behavioral therapy (CBT) has demonstrated efficacy in reducing fatigue severity in diverse clinical populations in specialized healthcare settings, with common treatment mechanisms identified across conditions. This study is the first to evaluate the feasibility and acceptability of a transdiagnostic CBT (tCBT) for a heterogeneous sample of patients suffering from severe and persistent fatigue in a primary care context. Methods A single-arm feasibility study was conducted in routine primary care. Adults with severe and persistent fatigue received a blended tCBT combining individual sessions and internet-based materials. Feasibility and acceptability were evaluated through adherence, completion, attrition, therapist fidelity, patient satisfaction, credibility, and negative effects. Preliminary effectiveness was evaluated by self-reported symptom change from pre- to post-treatment (6 months). Results Eighteen participants were enrolled, of whom fourteen completed the full intervention. Treatment adherence and therapist fidelity were satisfactory, and data attrition was minimal. Participants reported high satisfaction and treatment credibility. No serious adverse events were reported. Half of the participants reported some negative effects of treatment, primarily consisting of transient increases in fatigue and sleep disturbances. Large within-group reductions were observed in self-reported fatigue severity and functional impairment over the 6-month treatment period. Conclusions Preliminary findings suggest that tCBT for fatigue is feasible and acceptable in a primary care setting. Interpretation is limited by the small sample size and single-arm design. Larger randomized controlled trials are warranted to evaluate effectiveness and to determine which patients benefit most and through which mechanisms. Trial registration Pre-registered on Clinicaltrials.gov (NCT06341751), registration date: 2024-03-13.