Exercise performance and chronic pain in chronic fatigue syndrome: the role of pain catastrophizing.

OBJECTIVES

This study aimed to examine the associations between bodily pain, pain catastrophizing, depression, activity limitations/participation restrictions, employment status, and exercise performance in female patients with chronic fatigue syndrome (CFS) who experience widespread pain.

DESIGN

Cross-sectional observational study.

SETTING

A university-based clinic.

PATIENTS

Thirty-six female CFS patients who experienced widespread pain.

OUTCOME MEASURES

Patients filled in the Medical Outcomes Short-Form 36 Health Status Survey, the Chronic Fatigue Syndrome Activities and Participation Questionnaire, the Beck Depression Inventory, and the Pain Catastrophizing Scale, and underwent a maximal exercise stress test with continuous monitoring of electrocardiographic and ventilatory parameters.

RESULTS

Pain catastrophizing was related to bodily pain (r = -0.70), depression (r = 0.55), activity limitations/participation restrictions (r = 0.68), various aspects of quality of life ( r varied between -0.51 and -0.64), and exercise capacity (r varied between -0.41 and -0.61). Based on hierarchical multiple regression analysis, pain catastrophizing accounted for 41% of the variance in bodily pain in female CFS patients who experience chronic widespread musculoskeletal pain. Among the three subscale scores of the Pain Catastrophizing Scale, helplessness and rumination rather than magnification were strongly related to bodily pain. Neither pain catastrophizing nor depression was related to employment status.

CONCLUSIONS

These data provide evidence favoring a significant association between pain catastrophizing, bodily pain, exercise performance, and self-reported disability in female patients with CFS who experience widespread pain. Further prospective longitudinal studying of these variables is required.