High-intensity exercise improves multidimensional fatigue and health-related quality of life in rheumatoid arthritis: a randomized controlled study

Prolonged fatigue is prevalent in people with rheumatoid arthritis (RA), and physical activity is recommended as an adjunct treatment option to managing fatigue. However, the type and dose of physical activity is not established. The purpose of this randomized controlled multicenter study was to evaluate the effect of high-intensity interval training (HIIT) and strength exercise on fatigue, sleep, mood, pain and health-related quality of life in people with RA. In total, 87 participants diagnosed with RA, mean age 48 (SD 9.66) Years and 84% females, were randomly assigned to an intervention group (IG) (n = 43) performing supervised HIIT and strength exercise for 12 weeks, or a control group (n = 44) with counseling of the general physical activity recommendations. Self-administered measures were assessed at baseline, 3 months, 6 months and 12 months; the Multidimensional Fatigue Inventory (MFI 20), the Pittsburgh Sleep Quality Index (PSQI), the Hospital Anxiety and Depression Scale (HADS), pain (VAS), health-related quality of life (VAS-global). Disease activity was assessed with the DAS28-ESR. Statistical analyses were performed using Analysis of Covariance (ANCOVA), and mixed model repeated measure analysis. At 3 months, a significant mean group difference in change was found on MFI-20 subscales General fatigue -4.0 (95%CI -5.57 to -2.39), Physical fatigue -4.9 (95%CI -6.43 to -3.36), Reduced activity -2.5 (95%CI -3.84 to -1.20), and Reduced motivation -1.8 (95%CI -2.97 to -0.62), favoring the IG. Additionally, a significant mean group difference in change was seen on VAS-global -12.8 (95%CI -21.3 to -4.3), in favor of the IG. At 6 months follow-up, the significant mean group difference on General fatigue -2.4 (95%CI -3.85 to -0.92), Physical fatigue -3.7 (95%CI -5.25 to -2.10), Reduced activity -2.0 (95%CI -3.53 to -0.39), Reduced motivation -1.6 (95%CI -2.93 to -0.16) and VAS-global -9.2 (95%CI -17.47 to -0.94) persisted. At 12 months follow-up a significant mean group difference was seen on Physical fatigue, depression mood, pain and VAS-global (p-value < 0.05), still in favor of the IG. The high-intensity exercise intervention had a beneficial effect on multidimensional fatigue, and health-related quality of life in people with RA. The effect on fatigue and health-related quality of life persisted during the 12 months-follow up period indicating long-term effects. The trial was registered prospectively on “FoU in Sweden” (Research and Development in Sweden), (registration number: 275642), and retrospectively on Trial Gov. (NCT 05768165).