Rheumatoid arthritis is associated with exacerbated body composition deterioration in Kazakh females.

Objective: The aim of this study was to assess the magnitude of changes in nutritional body composition components as a consequence of rheumatoid arthritis (RA) and the extent to which these components are associated with RA clinical characteristics, serologic markers, and osteoporosis-related phenotypes (OP-RPs). Early pathologic signs, if detected, could assist in future preventative techniques.

Methods: The study sample was comprised of 260 women with RA and 168 first-degree female relatives without RA who returned for body composition measurements using bioelectrical impedance analysis, from a previously established epidemiologic study conducted in Kazakhstan.

Results: In multivariate logistic regression, body composition components, the fat mass index (odds ratio [OR], 0.848; 95% confidence interval [CI], 0.786-0.913; P < 0.001) and the phase angle (PA; OR, 0.654; 95% CI, 0.467-0.826; P = 0.001), were independently and significantly negatively associated with RA after disease development. In multilinear regression analysis, PA was consistently associated with OP-RP, specifically concerning the spongial bone mineral density (BMDSPN) and cortical index, where ageing, reduced PA and increased disease duration explained 31.5% of BMDSPN and 37.3% of cortical index variation.

Conclusion: Data on RA in women in Kazakhstan consistently show that fat mass index and PA act as independent major covariates associated with RA affection status. These findings suggest exacerbated body composition deterioration when compared with healthy controls, potentially indicating the early appearance of sarcopenia and likely cachexic-like properties. The data also suggest that PA could serve as a potential predictor of RA prognosis, and the concomitant development of osteoporosis.