To predict the effects of cognitive-behavioral therapy (CBT) and operant-behavioral therapy (OBT) in fibromyalgia syndrome (FMS).
A total of 125 patients who fulfilled the American College of Rheumatology FMS criteria were randomly assigned to CBT (n = 42), OBT (n = 43), or attention placebo (AP; n = 40). The pretreatment to 12-month followup reliability change index was used to determine clinically meaningful changes in pain intensity and physical impairment. Multinominal logistic regression analyses were used to determine the predictors of improvement in pain intensity and physical impairment for the entire sample. Analyses of variance were computed to compare the characteristics of responders and nonresponders in each of the 3 interventions.
At the 12-month followup, 53.5%, 45.2%, and 5% of patients in the OBT, CBT, and AP groups, respectively, reported clinically meaningful improvements in pain intensity. Similarly, 58.1%, 38.1%, and 7.5% of patients treated with OBT, CBT, and AP, respectively, reported clinically significant improvements in physical impairment. Prior to treatment, the OBT physical impairment responders displayed significantly more pain behaviors, physical impairment, physician visits, solicitous spouse behaviors, and level of catastrophizing compared with nonresponders. The CBT physical impairment responders, compared with nonresponders, reported higher levels of affective distress, lower coping, less solicitous spouse behavior, and lower pain behaviors.
The results of this study suggest that pretreatment patient characteristics are important predictors of treatment response and may serve as a basis for matching treatments to patient characteristics. Prospective outcome studies are needed to confirm whether the tailoring of treatment actually leads to better outcomes for patients with FMS.