Osteoprotegerin - does it play a protective role in the pathogenesis of bone loss in obese perimenopausal women?

Abstract

Introduction: Assessment of serum osteoprotegerin (OPG) concentrations in obese patients in comparison to healthy controls and evaluation of a possible correlation between OPG and other markers of bone turnover or calcitropic hormones.
Material and methods: 50 obese perimenopausal women without concomitant diseases (BMI 36.7 ± 4.1 kg/m², mean age 50.4 ± 4.9 yrs). The control group consisted of 19 healthy women (BMI 24.2 ± 2.1 kg/m²; mean age 53.8 ± 5.1 yrs). In all patients serum concentration of OPG, C telopeptide of type I collagen containing the crosslinking site (CTX), osteocalcin, parathormone (PTH) and vitamin D (25-OH-D₃) was assessed. Dual energy x-ray absorptiometry (the DXA method) of the lumbar spine and femoral neck was performed using a Lunar DPXL to measure bone marrow density (BMD).
Results: In obese perimenopausal women serum OPG, osteocalcin and 25-OH-D₃ levels were significantly lower, and the serum PTH level was significantly higher in comparison to healthy controls. A significantly positive correlation was found between serum OPG level and age in both obese and control subjects.
Conclusion: The serum OPG level in obese perimenopausal women is significantly lower in comparison to healthy controls and does not correlate significantly with biochemical markers of bone turnover, calcitropic hormones and BMD. It probably cannot play a protective role in the pathogenesis of bone loss in obese perimenopausal women.