Factors associated with the change of bone mineral density in female patients with rheumatoid arthritis

Objective: To study the risk factors of osteoporosis(OP) in female patients with rheumatoid arthritis(RA) , and the related clinical factors. Methods: The bone mineral density(BMD) of the lumbar vertebrae(L1-L4) , femoral neck and total femoral of 115 female patients with RA and 101 female healthy subjects area were measured by dual energy X-ray absorptiometry; and the clinical and laboratory indexes were observed in the meantime. Results: The incidence of OP in female patients with RA was significant higher than that in healthy subjects(P ＜ 0. 01) . The BMD of all positions in female patients with RA was lower than that in healthy subjects(P ＜ 0. 05-P ＜ 0. 01) . The RA patients diagnosed as having OP had lower BMD than those having not(P ＜ 0. 01) . The former had elder ages, longer years of menopause, longer duration of disease and morning stiffness, tender joint counts, higher HAQ scores and worse function of joint and X-ray status than the latter(P ＜ 0. 05-P ＜ 0. 01) . The osteoporotic fracture probability in patients with RA was obviously higher than that in healthy subjects in the next 10 years(P ＜ 0. 01) . The BMD of L1-L4 in female patients with RA who were taking corticosteroid was lower than that of patients taking no corticosteroid(P ＜ 0. 05) . Logistic regression analysis showed that menopauseOR = 4. 582(1. 503-13. 974) , P ＜ 0. 01］and X-ray statusOR = 2. 267(1. 233-4. 167) , P ＜ 0. 01) were the main risk factors for the OP in female patients with RA. Conclusions: Compared with the healthy subjects, the incidence of OP and the risk of osteoporotic fracture in female patients with RA rise apparently. The occurrence of OP is related with several risk factors, such as menopause, worse X-ray status and taking corticosteroid.