USING AMERICAN MEDICAL ASSOCIATION GUIDELINES FOR CLASSIFICATION OF DISABILITY IN CHRONIC FATIGUE SYNDROME

Abstract

Chronic Fatigue Syndrome (CFS) is a complex illness characterized by pervasive fatigue, sleep disturbance, neurocognitive problems, joint and muscle pain and numerous other symptoms. Persons with the illness face functional impairment that has not been clearly characterized. Because CFS is an emerging illness, there are few guidelines for the evaluation of patients. PURPOSE: The purpose of this study was to demonstrate that exercise testing can be reliably used to quantify disability in CFS patients. METHODS: Subjects comprised 203 persons previously diagnosed with CFS. Data were collected by means of standardized treadmill tests using a modified Bruce protocol with expired air collected for gas exchange analysis. American Medical Association guidelines were used to classify functional capacity based on oxygen consumption. RESULTS: The results of this study show that the majority of subjects were classified as having some functional impairment, with approximately 48% in the “moderate to severe” or “severe” categories. Actual peak oxygen consumption for subjects ranged from 36% to 76% of the value predicted by normative equations. These values differed significantly for each of the four impairment categories (p < 0.001). CONCLUSION: These findings confirm that CFS is a potentially disabiling condition. However, it is clear that even in patients with a clear diagnosis of CFS levels of impairment can differ considerably.Table