Relationship between total and regional bone mineral density and menopausal state, body composition and life style factors in overweight Japanese women

Abstract

Objective: To investigate whether menopausal state, body composition and lifestyle factors influence total and regional bone mineral density in overweight Japanese women.

Design: Cross-sectional study of women who were recruited to the weight reduction program held at community-based health promotion center in Tokyo area.

Subjects: A total of 178 women with a mean age of 48 y old (20-69 y) with a clear menstrual history and BMI over 24.

Measurements: Total, regional and lumbar spine bone mineral density (BMD) and body composition were measured using DXA (Lunar). Menstrual history was taken by a questionnaire and walking steps per day and energy intake were measured. Physical fitness was assessed by cardio-respiratory fitness and leg extension power. Subjects were divided into pre-menopausal and post-menopausal groups.

Results: Pre-menopausal group had significantly higher total body BMD as well as regional BMD than post-menopausal group. However, no differences in BMI, percentage fat and fat mass (FM) were seen between the two groups. The multiple regression analysis stepwise method revealed that total and regional BMD correlated with menopausal state and total FM independently. Total and regional BMD did not correlate with total non-fat soft tissue mass (NFSM), energy intake, walking steps or physical fitness levels. Trunk and lower extremities BMD correlated with corresponding regional FM and NFSM, and upper extremities BMD correlated with only corresponding body part NFSM after adjusting menopausal state.

Conclusion: Total and regional BMD had strong negative correlation with menopausal state rather than total FM in overweight Japanese women. Weight-bearing site BMD correlated with corresponding body part FM and NFSM and non-weight bearing site BMD only correlated with corresponding body part NFSM after adjusting for menopausal state.