Is age or the body mass index (BMI) more determinant of the bone mineral density (BMD) in geriatric women and men?

The objective was to determine the effect of the body mass index (BMI) and age on the bone mineral density (BMD) in geriatric women and men. 900 geriatric patients were included in the study. BMD was measured in the right femoral neck and the antero-posterior lumbar region. All geriatric patients were classified in 1 of 4 categories on the basis of their BMI, as underweight, ideal weight, overweight, and obese. They were separated into three groups, 65-74, 75-84 and 85 and older, according to age groups. While a significant relationship was only determined between the femoral BMD measurements and the BMI in men; significant relationship was shown between both the lumbar and the femoral BMD measurements and the BMI in women. Significant relationship was also determined between the femoral BMD measurements and the BMI and age among women. While the BMDs of those aged 65-74 years group were found to be high compared to those aged 75-84 years and those aged 85 years and older groups, no difference was found between the two groups. This study confirms the effect of a high BMI on femoral neck and L2-L4 BMD among older men and women, but the effect of age was not shown above 75 years of age.