Women with rheumatoid arthritis (RA) have an increased odds of having abnormal body fat distribution, sarcopenia and sarcopenic obesity, especially those with a normal weight, compared with men with RA or women without the disease, according to researchers in Baltimore, Maryland.
Dr. Jon T. Giles at the Johns Hopkins University School of Medicine and colleagues studied body composition of 189 men and women with RA and 189 age- and gender-matched controls to assess disease-related predictors of abnormal body phenotype.
The subjects underwent dual-energy X-ray absorptiometry for measurement of total and regional body fat and lean mass. Body mass index (BMI) was calculated and lifestyle factors, demographics and RA severity and treatment were considered for each patient.
Women with RA were significantly more likely to have sarcopenia, have excess fat and have sarcopenic obesity. This was not seen among men with RA or the controls.
Differences in body composition phenotypes were greatest for patients with normal weight and normal BMI.
Increasing joint deformity, higher self-reported disability scores, elevated C-reactive protein levels, rheumatoid factor seropositivity, and a lack of current treatment with disease-modifying antirheumatic drugs were significantly associated with abnormal body composition, Dr. Giles and colleagues report in the June issue of Arthritis & Rheumatism (Arthritis Care and Research).
"Abnormal body composition phenotypes are over-represented in patients with RA, particularly in those in the normal weight BMI range. RA-associated disease and treatment characteristics contribute to this increase in abnormal body composition," the authors point out.
"Because aberrant body composition is increasingly implicated as a key determinant of health, further investigation is needed to determine the causal factors for these body composition changes and to devise and test interventional strategies to reduce their effects on health outcomes in patients with RA."
Arthritis Rheum 2008;59:807-815
