Individuals with prediabetes have shown a greater response to high-intensity interval training than those with rheumatoid arthritis, according to a study recently published in Arthritis Research & Therapy. This finding supports previous research demonstrating impaired muscle remodeling ability in rheumatoid arthritis.
This study included 12 individuals with rheumatoid arthritis and 9 with prediabetes who were sedentary at baseline. These participants underwent 10 weeks of high-intensity interval training, completed body composition testing, vastus lateralis biopsies, and plasma collection before and after. Training included 3 sessions of graded treadmill exercise per week. Enzyme-linked immunosorbent assays were used to measure muscle interleukin-6 (mIL-6), plasma galectin-3, mIL-1 beta, mIL-8, mIL-10, muscle tumor necrosis factor-alfa (mTNF-alfa), and cytokines and myostatin in muscle. To analyze the interassociation of galectin-3, researchers examined a separate cohort of 47 individuals with rheumatoid arthritis and 23 matched controls.
High-intensity interval training was associated with improved maximal oxygen consumption in both groups and Disease Activity Score in 28 joints. Although galectin-3 reduction was not associated with training, it was significantly associated with better maximal oxygen consumption in those with rheumatoid arthritis (r=-0.57; P =.05). Those with rheumatoid arthritis who achieved both lower body fat and increased lean mass were on regimens of methotrexate, tofacitinib, or sulfasalazine. Improved body composition was associated with lower mTNF-alfa and IL-6 (r<-0.60; P <.05), although those with prediabetes showed a more significant association between greater lean mass and lower mIL-6 than those with rheumatoid arthritis (Fisher r-to-z P =.0004). Also among those with prediabetes, this greater lean mass was associated with lower muscle myostatin (r=-0.92; P <.05; Fisher r-to-z P =.026). Improved body composition was not associated with either hydroxychloroquine or TNF-inhibitors among those who exercised.
Limitations to this study included a small sample size and a resultant lack of significance in certain interassociations, as well as multiple pharmacological treatments among those with rheumatoid arthritis.
The study researchers concluded that “exercise-mediated body composition and cardiovascular risk improvements are closely tied to—and likely depend upon—effective muscle remodeling. However, the correlations of muscle remodeling markers (myostatin and cytokines) with favorable body composition outcomes were stronger in prediabetes than in [rheumatoid arthritis]. These differences provide further evidence to support the occurrence of abnormal muscle remodeling in [rheumatoid arthritis] and offer insights into the etiology of exercise intolerance and disability in [rheumatoid arthritis].”
Andonian BJ, Bartlett DB, Huebner JL, et al. Effect of high-intensity interval training on muscle remodeling in rheumatoid arthritis compared to prediabetes [published online December 27, 2018]. Arthritis Res Ther. doi: 10.1186/s13075-018-1786-6