BONE-DENSITY, BIOCHEMISTRY AND LIFE-STYLE

We have assessed the relationship between bone density, biochemistry a nd life-style factors in a cross-sectional study of 434 pre- and 357 p ostmenopausal women. Bone-mineral content (BMC) was measured in the no n-dominant forearm using single-photon densitometry. Bone mass was cor rected for bone size (BMC2) in a sub-set of 263 subjects. Correlation statistics and multiple regression analyses were used to identify phys ical and biochemical measurements that could be used to best predict B MC or BMC2. These were combined with lifestyle factors, using multiple logistic regression analysis, to identify women at risk of low bone d ensity. Cut-off values were taken as the 5th percentile of the bone de nsity distributions in pre-menopausal women. In postmenopausal women, using BMC2 values to define ''risk'', and using age, creatinine, alkal ine phosphatase, thyroxine treatment, and calcium supplementation as p redictors, a sensitivity of 73% and a specificity of 95% were achieved . Such a model may be of use as a ''first pass'' screening test for os teoporosis.