Long-term pain and health economic outcomes in adults receiving multidisciplinary CBT for chronic pain: the role of psychological inflexibility.

Background: Little is known about whether the recommended, non-pharmacological treatments for chronic pain yield reductions in healthcare utilization, social costs and increased productivity in actual practice.

Methods: The primary aim of this study (n = 232) was to conduct secondary analyses of health economic outcomes using data from national registries combined with clinical outcome data from a large pain center in Sweden conducting multidisciplinary treatment based on a cognitive behavioral approach. Specifically, pain-related and health economic outcomes at post-treatment and one, two and three years after discharge were examined. In an exploratory fashion, we also investigated whether sociodemographic characteristics, pain-related variables, and psychological inflexibility predicted these long-term pain-related and health economic outcomes. We also examined psychological inflexibility as a potential mediator of these outcomes.

Results: Small and moderate sized improvements in pain, pain interference, and depression observed at post-treatment were mostly maintained at both the 1- and 3-year follow-up. A very similar pattern was observed for health economic outcomes, with 1-year follow-up gains being maintained at long-term follow-up. Baseline psychological inflexibility predicted long-term pain-related outcomes, but not health economic outcomes. Changes in psychological inflexibility during treatment and follow-up mediated long-term pain-related outcomes and the total number of health care visits.

Conclusions: The present findings add to a small body of literature indicating that the improvements in pain and related difficulties following multidisciplinary, pain-focused, CBT programs persist at least three years following treatment, and these are accompanied by modest improvements in health economic outcomes over the same interval. Psychological inflexibility seems to be predominately associated with long-term clinical outcomes in pain management, and it also appears relevant to the number of health care visits.