Sustainability of cognitive behavioural interventions for chronic back pain: A long-term follow-up

Background: There is a significant research gap with respect to the long-term sustainability of psychological treatment effects in chronic pain patients. This study aimed to investigate long-term treatment effects of two psychological treatments: cognitive behavioural therapy (CBT) as a broad-spectrum approach and exposure as a specific intervention for fear-avoidant pain patients.Methods: Patients with chronic low back pain were randomized to CBT or exposure in vivo. Long-term follow-up (LTFU) data were available for 64 patients up to 8 years after treatment, with a response rate of 73%. The primary outcomes were pain-related disability and pain intensity and secondary outcomes were emotional distress, psychological flexibility, catastrophizing and pain-related fear. The data analysis was performed with longitudinal multilevel modelling.Results: Multilevel analyses showed improvements in all primary outcomes as well as all secondary outcomes from pre-treatment to LTFU for both treatments. The mean proportion of cases meeting reliable and clinical improved criteria in all primary outcome was 36% (range: 22%-46%) in the exposure group and 50% (range: 33%-60%) in the CBT group. Dropout analyses revealed significantly higher deterioration rates over time. Pre-treatment to LTFU effect sizes of the primary outcomes ranged from 0.54 to 1.59.Conclusions: Our results indicate that the effects of psychological treatments might be stable over several years. Treatment gains for exposure as a stand-alone treatment seem to be of shorter duration than a general CBT intervention. Thus, psychological treatments might offer a promising and sustainable long-term perspective for patients with chronic back pain.