Association of body mass index and waist circumference with bone metabolism markers in Iranian elderly

Objective: There is no agreement on the role of obesity as a protection factor or unfavorable factor on bone. In the present study, the association of body mass index (BMI) and waist circumference (WC) with osteocalcin, C-terminal telopeptide of type 1 collagen (CTX-I), hs-CRP, parathormone (PTH) and 25-hydroxyvitamin D (25(OH)) in elderly was investigated.Methods: This cross-sectional study was conducted on 178 elderly residents in Tehran, with a mean age of 67.04 (60-83). Serum osteocalcin, hsCRP, 25(OH) D, PTH and urine CTX-I, were measured for all participants. Waist circumference, weight and height were measured and BMI was calculated. Linear regression and Pearson Correlation were performed to evaluate the relation of BMI and waist circumference with other variables.Results: A significant inverse association was found between BMI with osteocalcin ((Beta = -.171, p= 0.027)) after control for covariates. In addition, there were a statistically significant relation of BMI and WC with hs-CRP (Beta =0.246, p= 0.002 and Beta =0.219, p= 0.006, respectively), and PTH (Beta = 0.1169, p= 0.040 and Beta = 0.200, p= 0.018), respectively). The present study didn’t show a statistically significant relation of BMI and WC with urine CTX-I after adjustment for potential confounders (Beta =-0.143, p= 0.065 and Beta = -0.104, p= 0.183, respectively).Conclusion: The present study has concluded that obesity is an undesirable factor in bone by reduced serum osteocalcin and increasing hs-crp and PTH which contribute to bone resorption, beauty of this region.

کلیدواژه ها:

obesity ، bone marker ، elderly ، osteocalcin ، CTX-I