Cognitive-behavioral therapy for persistent pain: does adherence after treatment affect outcome?

It is a tenet of cognitive behavioral treatment of persistent pain problems that ex-patients should adhere to treatment methods over the longer term, in order to maintain and to extend treatment gains. However, no research has quantified the causal influence of adherence on short-term outcome in this field. The aims of this study are to assess determinants of adherence to treatment recommendations in several domains, and to examine the extent to which cognitive and behavioral adherence predicts better outcome of cognitive behavioral treatment for persistent pain. Longitudinal data from a sample of 2345 persistent pain patients who attended a multicomponent treatment programme were subjected to structural equation modeling. Adherence emerged as a mediating factor linking post-treatment and follow-up treatment outcome, but contributed only 3% unique variance to follow-up outcomes. Combined end-of-treatment outcomes and adherence factors accounted for 72% of the variance in outcome at one-month follow-up. Notwithstanding shortcomings in the measurement of adherence, these findings question the emphasis normally given to adherence in the maintenance of behavioral and cognitive change, and clinical implications are discussed.