Kognitive Verhaltenstherapie bei chronischen Rückenschmerzen: Modelle, Indikation, Wirkfaktoren

The purpose of the doctoral thesis was to was to examine the supplemental value of EMG biofeedback training when added to an outpatient cognitive-behavioural treatment of chronic back pain (CBP). Additionally it was intended to proof the assumptions made by the symptom-specifity model of chronic low back pain, to identify pretreamtent factors associated with dropout from cognitve-bahavioural treatment of chronic back pain and to identify central therapeutic mechanisms in cognitive-behavioural treatment of chronic back pain. 128 chronic back pain patients were assigned to Cognitive-Behavioural Therapy (CBT), Cognitive-Behavioural Therapy supported by biofeedback (CBTB) or Wait List Control (WLC). Measures (questionnaires as well as psychophysiological measures of stress reactivity to different stress conditions and muscle tension) were taken at pre-treatment, posttreatment and 6-months follow up. The results at post-treatment indicated significant improvements in functioning on measures of pain intensity (ES = .79), perceived level of disability (ES = .52), coping strategies (ES = 1.09), psychological distress (ES = .41) and other outcome variables in both CBT and CBTB conditions. These improvements were not evident for the WCL condition. At 6-months follow-up, treatment gains were maintained for both treatment groups. The addition of biofeedback had positive effects on the acceptance of treatment and on satisfaction with treatment. CBP patients showed patterns of higher muscular reactivity in the lower back region for CBP patients during the exposure to a personally relevant stressor, a cognitive stressor and a social stressor. Additionally, CBP patients showed specific muscular responses in the lower back. The results support the assumptions made by the symptom-specificity model of chronic back pain, but only for lower back, not for mid back and neck. Concerning the dropout analysis, twenty-three patients (18%) were classified as dropouts. Low psychological distress, low medication intake, and low treatment satisfaction were significantly associated with dropout. Other demographic variables, pain related variables, attributions, and attitude towards treatment were not associated with treatment attrition. The associations were only valid for early dropouts. It is concluded that cognitive-behavioural treatment of chronic pain treatment should be better adapted to less psychologically distressed patients to avoid treatment dropout.As far as therapeutic mechanisms are concerned, changes in depression from pre-treatment to post-treatment accounted for unique variance in changes in pain intensity and pain disability. The reported associations were significant after controlling for other variables that were described to be predictive for pain intensity, pain disability and treatment outcome in chronic pain patients. It is concluded that reducing pain-related depression could be a central therapeutic mechanism in cognitive-behavioural treatment of chronic back pain.