Bone mineral density: reference values and correlates for Bangladeshi women aged 16-65 years

Studies examining the reference values of bone mineral density (BMD) and their patterns at different ages are largely based on data generated from developed countries. The objective of this study was to estimate reference values of BMD, along with their correlates, for women living in urban and suburban areas of Bangladesh.

Dual-energy X-ray absorptiometry scans were performed on 500 women 16-65 years of age. Reference values at the lumbar spine (LS) and femoral neck (FN) were estimated after adjusting for height and weight. In addition, multiple linear regression analysis was used to examine correlates of BMD at the LS and FN.

Mean BMD was highest at the LS and FN in women 16-19 (1.001-1.007 g/cm(2)) and 16-22 years of age (0.880-0.888 g/cm(2)), respectively, and gradually declined with increasing age thereafter. BMD decreased at an annual rate of 0.0027 g/cm(2) at the LS and 0.0046 g/cm(2) at the FN among women aged 16-45 years. For women 46-65 years of age, the respective figures were 0.0073 and 0.0083 g/cm(2). In both age groups, body weight was positively associated with BMD at both sites, and with height only at the LS. In addition, years of pill use was positively associated with BMD at the LS among women aged 16-45 years. BMD levels at both sites began to decline during the early twenties among Bangladeshi women.

Age-specific BMD data generated in this study could be useful for interpreting bone densitometry data among women in Bangladesh and other South Asian countries.