Two-Year Follow-Up of a Randomized Clinical Trial of Inpatient Multimodal Occupational Rehabilitation Vs Outpatient Acceptance and Commitment Therapy for Sick Listed Workers with Musculoskeletal or Common Mental Disorders.

Purpose There is a lack of results on long-term effects of return to work interventions. We previously reported that an inpatient multimodal occupational rehabilitation program (I-MORE) was more effective in reducing sickness absence and facilitating return to work (RTW) at 12 months follow-up compared to an outpatient program that consisted mainly of Acceptance and Commitment Therapy (O-ACT). We now report the 2-year outcome data. Methods A randomized clinical trial with parallel groups. Participants were 18-60 years old, sick listed with musculoskeletal, common mental or general/unspecified disorders. I-MORE lasted 3.5 weeks and consisted of ACT, physical training and work-related problem solving. O-ACT consisted mainly of 6 weekly sessions (2.5 h. each) of ACT in groups. Outcomes were cumulated number of days on medical benefits and time until sustainable RTW (1 month without medical benefits) during 2-years of follow-up, measured by registry data. Results For the 166 randomized participants, the median number of days on medical benefits was 159 (IQR 59-342) for I-MORE vs 249 days (IQR 103-379; Mann-Whitney U test, p = 0.07), for O-ACT. At 2 years, 40% in I-MORE received long-term benefits (work assessment allowance) vs 51% in O-ACT. The crude hazard ratio (HR) for sustainable RTW was 1.59 (95% CI 1.04-2.42, p = 0.03) and the adjusted HR 1.77 (95% CI 1.14-2.75, p = 0.01), in favor of I-MORE. Conclusions The 2-year outcomes show that I-MORE had long-term positive effects on increasing work participation for individuals sick listed with musculoskeletal and mental disorders. Further follow-up and economic evaluations should be performed.