Publication:

The effect of body mass index on bone mineral density in postmenopausal women

Background The aim of this study was to evaluate the association between BMI and BMD among postmenopausal women.

Methods A total of 121 healthy female patients, aged 65.67±8.59 years, previously menopaused, were enrolled. Subjects were divided into five subgroups according to their BMI. History of fracture and BMD were recorded and compared between groups.

Results Among the 121 subjects, 77 (63.6%) individuals had a normal BMD, 32 (26.4%) had osteopenia, and 12 (9.9%) were diagnosed with osteoporosis. Mean of waist circumference was 96.1±8.52cm. The prevalence of fractures was 29.8% in this study. A simple correlation analysis revealed that waist circumference was negatively related to lumbar spine BMD (r= -0.374, p=0.03) and lumbar spine BMD T score (r= -0,352 p=0.002) whereas body weight was positively related to BMD of lumbar spine BMD (r=0.41, p=0.0001) and lumbar spine BMD T score (r=0,31 p=0.001). Age and years since menopause (YSM) were negatively correlated with BMD and T score (p=0.001, p=0.0001, respectively).

Conclusions Even though higher BMI seems to have positive impact on bone density thanks to hormonal and mechanical reasons, increased waist circumference is a sign of a metabolic syndrome and systemic inflammation which are known as having negative effect on bone density. Therefore, postmenopausal women specifically with abdominal obesity should be evaluated for osteoporosis.