Role of psychological aspects in both chronic pain and in daily functioning in chronic fatigue syndrome: a prospective longitudinal study.

In addition to fatigue, many patients with chronic fatigue syndrome (CFS) experience chronic musculoskeletal pain. We aimed at examining the role of catastrophizing, coping, kinesiophobia, and depression in the chronic pain complaints and in the daily functioning of CFS patients. A consecutive sample of 103 CFS patients experiencing chronic widespread musculoskeletal pain completed a battery of questionnaires evaluating pain, daily functioning, and psychological characteristics (depression, kinesiophobia, pain coping, and catastrophizing). Thirty-nine patients participated in the 6-12-month follow-up, consisting of questionnaires evaluating pain and pressure pain algometry. Correlation and linear regression analyses were performed to identify predictors. The strongest correlations with pain intensity were found for catastrophizing (r = -.462, p < .001) and depression (r = -.439, p < .001). The stepwise multiple regression analysis revealed that catastrophizing was both the immediate main predictor for pain (20.2%) and the main predictor on the longer term (20.1%). The degree of depression was responsible for 10% in the observed variance of the VAS pain after 6-12 months. No significant correlation with pain thresholds could be revealed. The strongest correlations with daily functioning at baseline were found for catastrophizing (r = .435, p < .001) and depression (r = .481, p < .001). Depression was the main predictor for restrictions in daily functioning (23.1%) at baseline. Pain catastrophizing and depression were immediate and long-term main predictors for pain in patients with CFS having chronic widespread musculoskeletal pain. They were also correlated to daily functioning, with depression as the main predictor for restrictions in daily functioning at baseline.