Women with rheumatoid arthritis (RA) are more likely to have sarcopenia and sarcopenic obesity compared with male patients with RA, according to a study in the Journal of Clinical Rheumatology.
In this cross-sectional study, researchers compared the prevalence of sarcopenia and factors contributing to sarcopenia in 105 adult patients with RA and 100 healthy controls. Sarcopenia was defined as the presence of low muscle strength in handgrip and low muscle mass in the appendicular skeletal muscle mass (ASM) index, as measured by dual-energy x-ray absorptiometry.
Patients with RA had a significantly lower percentage of lean mass (odds ratio [OR], 0.999; 95% CI, 0.99962–0.99990; P =.0021) and ASM (OR, 0.568; 95% CI, 0.37449–0.80971; P =.0038) compared with the control group. Only women with RA had lower lean parameters, including total lean mass, percentage of lean mass, and ASM. Women with RA had a significantly lower ASM index compared with controls (31.0% vs 11.9%, respectively; OR, 3.3; 95% CI, 1.5–7.4; P =.0028), with no differences observed between men.
Both fat mass and most adipose indices were significantly higher in men and women with RA. Women with RA had a higher prevalence of sarcopenia as well as sarcopenic obesity. In the multivariable analysis, sarcopenia was associated with previous fragility fractures (OR, 5.460; 95% CI, 1.05359–3.27608; P =.0470). The univariate analysis linked sarcopenia with long-term corticosteroid treatment, high cumulative corticosteroid dose, previous fragility fractures, low total lean mass, and low ASM.
Limitations of the study included its cross-sectional design as well as the small number of participants in the study with sarcopenia. Additionally, sarcopenia was considered as the primary outcome and the authors acknowledge that a reverse relationship cannot be excluded.
Due to the study’s limitations, the researchers suggest “longitudinal studies for causal associations are needed.”
Brance ML, Di Gregorio S, Pons-Estel BA, et al. Prevalence of sarcopenia and whole-body composition in rheumatoid arthritis. J Clin Rheumatol. Published online September 4, 2020. doi:10.1097/RHU.0000000000001549