Bone mineral density in postmenopausal women

Abstract

The impacts of various factors on bone mineral density (BMD) differ across diverse population. The aim of this study was to determine the relationship between BMD in the femoral neck (FN) and lumbar spine (LS) with some common clinical, demographic, and biochemical parameters in postmenopausal women. In this cross-sectional case-control study, all postmenopausal women of the Amirkola Health and Ageing Project (AHAP) who performed bone densitometry were included. BMD at FN and LS was measured by DXA method. Data regarding clinical, demographic, and biochemical characteristics were provided. OP was diagnosed by the International Society for Clinical Densitometry criteria. Pearson correlation and multivariate regression analyses with simultaneous adjustment were performed to determine relationship. Five hundred thirty-seven women with mean age of 67.9 ± 6.7 years and mean menopause duration (MD) of 15.8 ± 5.1 years were studied. MD correlated negatively with FNBMD and LS-BMD g/cm 2 ( r = −0.405, P = 0.001 and r = −0.217, P = 0.001). Body mass index (BMI) correlated positively with FN and LS-BMD g/cm 2 ( r = 0.397, P = 0.001 and r = 0.311, P = 0.001). The association of MD with risk of FNOP was stronger than LS-OP. Obesity and metabolic syndrome (MS) and higher serum ferritin reduced the risk of OP at both LS and FN similarly, whereas the impacts of parity, prior fracture, high level of education, and physical activity were significantly different across BMD measurement sites. The results of this study indicated a significant association between OP and MD, obesity, parity, MS, history of fracture, serum ferritin, level of education, and physical activity. However, the direction and the strength of association varied across BMD measurement sites.