Effect of Aerobic Exercise Training on Fatigue in Rheumatoid Arthritis: A Meta-Analysis.

OBJECTIVE: Rheumatoid arthritis (RA) fatigue is not being well-managed currently, and evidence of effective interventions is limited. Aerobic exercise may provide benefit to treat fatigue in RA. Therefore, the purpose of this meta-analysis is to analyze the effect of aerobic land-based exercise on fatigue in RA. METHODS: A literature search was conducted using PubMed, Cochrane Library, Embase, and trial registers to identify randomized controlled trials (RCTs) with a supervised land-based aerobic exercise program performed with an intensity between 50% and 90% of maximal heart rate, of at least 15 minutes' duration, performed at least 2 times a week, and lasting for a time period of at least 4 consecutive weeks. Risk of bias was assessed using the Cochrane tool. A meta-analysis of fatigue outcomes was performed by calculating the standardized mean difference (SMD) using a random-effects model. RESULTS: Five RCTs were included. None of the trials selected patients with RA for having fatigue. Risk of bias was low in 3 RCTs and unclear in 2. Land-based aerobic exercise programs had a positive effect on fatigue in RA compared to no exercise at 12 weeks, SMD -0.31 (95% confidence interval [95% CI] -0.55, -0.06). At 24 weeks, the effect of aerobic land-based exercise was smaller and not statistically significant: SMD -0.15 (95% CI -0.33, 0.02). CONCLUSION: There is evidence with low risk of bias that an aerobic exercise program is effective in reducing fatigue among patients with RA, especially in the short term; however, effects are small. To substantiate the evidence, RCTs should be performed in patients with RA selected for having fatigue.

Relationship between objectively assessed physical activity and fatigue in patients with rheumatoid arthritis: inverse correlation of activity and fatigue.

OBJECTIVE: 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 whether daily activity level is associated with fatigue in patients with RA, and 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: A total of 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 = 0.03). Pain, disability, coping, and cognition were not associated significantly with daily activity level. CONCLUSION: 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 sex, age, disease duration, pain, disability, or other fatigue-related factors.

Association between fatigue and pain in rheumatoid arthritis: does pain precede fatigue or does fatigue precede pain?

OBJECTIVE: Fatigue and pain are important symptoms for patients with rheumatoid arthritis (RA), but their temporal association is unknown. Therefore, the objective of this study was to investigate the longitudinal relationship between fatigue and pain in patients with RA using time-lag models. METHODS: Consecutive RA outpatients (n = 228) were enrolled for this 1-year study. Fatigue was assessed monthly with the Checklist Individual Strength (CIS; range 8-56) and pain was assessed monthly with the bodily pain subscale (inverted, range 0-100) of the Short Form 36. The association between monthly changes in fatigue and pain was analyzed using longitudinal regression (mixed models), using the same months and with a 1-month time lag. RESULTS: A total of 198 patients were included in the analyses. At baseline, the mean ± SD pain score was 35.23 ± 19.82 and the mean ± SD CIS fatigue score was 31.0 ± 12.4. Severe fatigue at baseline (CIS score ≥35) was present in 42% of the patients. The mean ± SD patient-averaged CIS fatigue score over 1 year was 30.9 ± 6.0 and the mean ± SD patient-averaged pain score over 1 year was 36.4 ± 18.3. The longitudinal regression analysis showed a significant positive relationship between fatigue and pain during the same month (ß = 2.04; 95% confidence interval 1.82, 2.27). The models using a time lag showed no significant association between changes in pain and changes in fatigue. CONCLUSION: In established RA, pain and fatigue show monthly fluctuations that are synchronous rather than showing a temporal relationship with a time lag; within this timeframe, the results do not indicate that one precedes the other.