The present paper describes a population survey of bone mineral density (BMD) on the third lumbar vertebra (L3) using dual X-ray absorptiometry fixed in a van (mobile DXA) with lateral projection. Subjects were 387 persons aged 65 to 84 years living in Koganei City, a western suburb of Tokyo. This is the baseline survey of the 10-year project “Longitudinal Interdisciplinary Study on Aging” supported by Tokyo Metropolitan Institute of Gerontology (TMIG-LISA).
As for the pattern of age-related BMD calculated in the range-of-interest (ROI) being set in the center of vertebral body to eliminate the posterior segment of vertebra and/or secondary hyperostotic changes with aging, the mean BMD of L3 declined in females from 0.514±0.121g/cm2 (mean±standard deviation) in age-group 65–69 to 0.377±0.137 g/cm2 in age-group 80–84. In males, it showed a decrease from 0.731±0.155 in 65–69 to 0.613±0.158 in 75–79 but a slight (insignificant) increase at age-group 80–84. There were significant differences of mean BMD between males and females in each age-group and in average. BMD was significantly associated with age (negatively) and body mass index (positively) in the multiple regression analysis.
Bone mineral density Mobile DXA Community elderly Epidemiology TMIG-LISA