The relationship between objectively assessed physical activity and fatigue in patients with rheumatoid arthritis: Activity and fatigue are inversely correlated
Copyright © 2013 American College of Rheumatology
- Accepted manuscript online: 10 DEC 2013 02:33PM EST
- Manuscript Accepted: 26 NOV 2013
- Manuscript Revised: 19 NOV 2013
- Manuscript Received: 28 FEB 2013
- Dutch Rheumatoid Arthritis Foundation
- Cited By
Background Fatigue is generally associated with low physical activity in patients with various chronic medical conditions. However, such an association has not been reported among patients with rheumatoid arthritis (RA). The objectives of this study were to investigate 1) whether daily activity level is associated with fatigue in patients with RA, and 2) whether pain, disability, coping, and/or cognition are associated with the level of daily activity.
Methods Patients with RA who visited our outpatient clinic were recruited consecutively. Fatigue severity was measured using the Checklist Individual Strength (CIS20). Physical activity was measured for 14 consecutive days using an ankle-worn actometer. The daily activity level of each patient was calculated, and each patient was classified as having a low or high activity level with respect to the group average. Data were analyzed by linear regression.
Results 167 patients were included in the analysis; 25% had a low activity level, and 75% had a high activity level. A regression analysis revealed that higher activity levels were associated with reduced fatigue (p=0.008). The mean (±SD) CIS-fatigue score was 30.9 ± 12.3 among the patients with a high activity level and 35.7 ± 12.8 among the patients with a low activity level (p=0.015). Pain, disability, coping, and cognition were not associated significantly with daily activity level.
Conclusions Among patients with RA, a higher level of daily physical activity was associated with reduced levels of fatigue. This relationship was not explained by differences in gender, age, disease duration, pain, disability, or other fatigue-related factors. © 2013 American College of Rheumatology.