RESUMO
OBJECTIVE: To evaluate the association between circulating leptin and bone mineral density (BMD) in patients with rheumatoid arthritis (RA). METHODS: One-hundred thirty postmenopausal women with RA were assessed for body mass index (BMI), disease characteristics, history of drug use, rheumatoid factor, and erythrocyte sedimentation rate (ESR). BMD (g/cm(2)) was determined in the hip and spine by DEXA. Serum leptin concentrations were measured by ELISA. Spearman's correlation coefficients (rho) were determined between BMD and leptin and other variables. A multiple regression analysis was used to adjust for confounders. RESULTS: Patients' serum leptin levels varied widely (range 2-128 ng/ml). Thirty-three patients (25%) had osteoporosis. Higher levels of leptin correlated significantly with BMD in the lumbar spine (rho = 0.17, p = 0.04) and total hip (rho = 0.21, p = 0.01). The variables that were negatively correlated with BMD were age, duration of menopause, and ESR. After adjustment for confounders, leptin was no longer associated with BMD. In the multivariate model, factors that remained associated with BMD in the total hip were age (p = 0.021) and BMI (p = 0.003); and the factors that remained associated with BMD in the lumbar spine were BMI (p = 0.03) and ESR (p = 0.01). CONCLUSION: No relevant association was found between circulating leptin levels and BMD in patients with RA in this cross-sectional study. Followup studies are needed to evaluate whether abnormal leptin levels confer a risk for fractures due to osteoporosis.
Assuntos
Artrite Reumatoide/sangue , Densidade Óssea , Leptina/sangue , Adulto , Idoso , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Osteoporose/sangue , Estatísticas não ParamétricasRESUMO
In this cross-sectional study, we assessed the relationship between circulating TNF-alpha and E-selectin (sE-selectin) with extraarticular involvement and severity of joint disease in RA. We compared 56 patients who had RA and extraarticular involvement (ExRA) with a group of 84 patients with only articular involvement (non-ExRA). ExRA had higher circulating TNF-alpha than non-ExRA (32 +/- 9 vs. 28 +/- 6 pg/mL, P = 0.002). sE-selectin levels did not differ between both groups. sE-selectin correlated with tender joint count (rho = 0.19, P = 0.03), morning stiffness (rho = 0.19, P = 0.03), severity of pain (rho = 0.21, P = 0.02), disease activity (assessed by the patient) (rho = 0.21, P = 0.02), HAQ-DI (rho = 0.29, P = 0.004), and rheumatoid factor titers (rho = 0.31, P = <0.001). Circulating TNF-alpha had no correlation with sE-selectin or disease activity. We concluded that sE-selectin correlated with severity of joint disease, further follow-up studies should evaluate if sE-selectin is useful as prognosis marker for progression of articular damage.