Lifestyle and body composition changes in patients with rheumatoid arthritis during the COVID-19 pandemic: A retrospective, observational study.

Objectives: Behavioral restrictions and staying at home during the COVID-19 pandemic have affected lifestyles. It was hypothesized that patients with rheumatoid arthritis (RA) decreased their activities of daily living (ADL) and exercise during the pandemic. The aim of this study is to investigate the changes in lifestyle and body composition.

Methods: Data were obtained from an observational study (CHIKARA study). Of 100 RA patients, 70 (57 women, 13 men) were followed-up with measurements of grip strength, as well as muscle mass, fat mass, and basal metabolic rate by a body composition analyzer. Changes in ADL and exercise were evaluated using a visual analog scale. The relationships between changes in ADL or exercise and body composition were investigated.

Results: Muscle mass and grip strength were significantly lower after behavioral restrictions compared to the periods before restrictions (34.0 vs 34.7 kg, P < 0.001; 16.2 vs 17.2 kg, P = 0.013, respectively). Fat mass was significantly greater after behavioral restrictions compared to the periods before restrictions (16.2 vs 15.5 kg, P = 0.014). The mean decrease in ADL was 44%, whereas that of exercise was 20%.The change in muscle mass ( = -0.335, P = 0.007) was the only independent factor for the change in exercise on multivariate analysis.

Conclusions: Muscle mass and grip strength decreased and fat mass increased in RA patients with the behavioral restrictions of the COVID-19 pandemic. Muscle mass decreased in patients without exercise. Maintenance of muscle mass may be important during the COVID-19 pandemic.