A study of the link between bone turnover markers and bone mineral density with inflammation and body mass in postmenopausal women with active rheumatoid arthritis.

In this study, the levels of bone turnover markers (BTMs) and bone mineral density (BMD) were studied in relation to body mass and several inflammatory markers, in postmenopausal patients with rheumatoid arthritis (RA). Fifty-nine postmenopausal women with active RA (lean, overweight, obese) were studied. The femoral BMD and serum levels of BTMs: osteocalcin (OC) and collagen type I cross-linked C-telopeptide fragments (CTX), and osteopontin (OPN), resistin, high sensitivity C-reactive protein, interleukin-6, tumor necrosis factor (TNF)-α in these patients were measured. It has been noticed that obese women had significantly higher total femoral BMD and total T-score compared to the lean subjects (p ≤ 0.01). The significant associations of BMD measures and CTX levels with body mass parameters (p ≤ 0.01 and p < 0.05, respectively) were found. Values of neck BMD adjusted for BMI were inversely associated with concentrations of TNF-α (p < 0.05). Osteocalcin levels inversely correlated with resistin (p ≤ 0.01) and CTX levels positively correlated with OPN (p ≤ 0.01). There were found no associations between BTMs and BMD with other inflammatory indices. Inverse correlations between OPN levels and body mass (p < 0.05), waist circumference (p < 0.05), and duration of postmenopausal period (p ≤ 0.01) were observed. Findings of the present study suggest that body mass and inflammatory markers, most of all OPN, resistin and TNF-α, play an important role in bone metabolism in postmenopausal women with active RA.