Kuninori Maruta

Difference in the effect of adiposity on bone density between pre- and postmenopausal women.

OBJECTIVES Elevated bone mineral density (BMD) in obese women is partially attributable to the higher circulating estrogen levels derived from extraglandular aromatization in adipose tissue. However, it remains unclear whether there is an effect of overall adiposity on BMD in both pre- and postmenopausal women. The difference in the effect of overall adiposity on BMD between pre- and postmenopausal women was investigated. MATERIALS AND METHODS Subjects were 296 premenopausal women with regular menstruation and 233 postmenopausal women. Age, age at menarche, years since menopause (YSM, in postmenopausal women), weight, height, and body mass index were recorded. Total fat mass amount, lean mass amount, and percentage of body fat were measured by whole body scanning with dual-energy X-ray absorptiometry (DEXA). Lumbar spine BMD (L2-L4) was measured by DEXA. In each group, significant determinants of BMD were investigated using univariate and stepwise multiple regression analysis. RESULTS In postmenopausal women, YSM, lean mass amount, total fat mass amount, and height were significant determinants of BMD (R(2)=0.273, P<0.001). In premenopausal women, only two variables including lean mass amount and age at menarche were significant determinants of lumbar spine BMD (R(2)=0.110, P<0.001), but total fat mass amount and percentage of body fat were not significant determinants of BMD. CONCLUSION The effect of overall adiposity on BMD is more prominent in postmenopausal women than in premenopausal women.

The effect of menopause on regional and total body lean mass

OBJECTIVES To investigate the effect of menopause on regional and total body lean mass. METHODS Evaluation of 123 healthy premenopausal women (40.6 +/- 10.8 years) and 123 healthy postmenopausal women (61.8 +/- 7.5 years). All subjects were right side dominant. Regional (head, bilateral arms, trunk, and bilateral legs) and total body lean mass were measured using whole-body scanning by dual-energy X-ray absorptiometry. Baseline characteristics including age, height, weight, and menopausal state were recorded. These variables were compared between pre- and postmenopausal women. In all subjects, correlations between regional or total body lean mass and baseline characteristics were investigated using univariate and multiple regression analyses. RESULTS Height, and lean mass of the trunk, bilateral legs and total body were significantly lower in postmenopausal women than in premenopausal women, while lean mass of the bilateral arms did not differ between the two groups. On univariate regression analysis, bilateral arms lean mass was positively correlated with height (P < 0.001). Trunk, bilateral legs, and total body lean mass were inversely correlated with age and menopausal state (P < 0.001), but were positively correlated with height (P < 0.001). After adjusting for age and height, trunk lean mass was still correlated with menopausal state (P < 0.01). CONCLUSIONS Menopause induces lean mass loss, independent of aging and height. Trunk lean mass is more prone to decline with menopause than lean mass of other sites.

Relationship between body fat distribution and bone mineral density in premenopausal Japanese women

Objective To investigate the relationship between body fat distribution and bone mineral density (BMD). Methods Subjects were 282 premenopausal women (mean age ± standard deviation [SD], 38.8 ± 8.5 years; range, 20–51 years) with regular menstrual cycles. Baseline characteristics included age, age at menarche, height, weight, body mass index ([BMI], weight/height2), and parity. Anthropometric characteristics including the ratio of trunk fat mass to leg fat mass (trunk–leg fat ratio), percentage of body fat, and total body lean mass were measured by whole-body scanning with dual-energy x-ray absorptiometry. Lumbar spine BMD (L2–4) was also measured by dual-energy x-ray absorptiometry. Correlations of BMD to baseline and anthropometric characteristics were investigated using univariate and multivariate analysis. Results Although height, trunk–leg fat ratio, and total body lean mass were positively correlated with lumbar spine BMD (r = .18, P < .01; r = .17, P < .01; and r = .25, P < .001; respectively), age at menarche was inversely correlated with BMD (r = −.19, P < .01). On multivariable analysis, trunk–leg fat ratio, height, age at menarche, and total body lean mass were still independently correlated with lumbar spine BMD (P < .05). However, total fat mass was not correlated with BMD. Conclusion Upper body fat distribution rather than overall adiposity is associated with lumbar spine BMD in premenopausal women. Humoral factors associated with body fat mass appear to influence lumbar spine BMD.

The contribution of menopause to changes in body-fat distribution.

Objective: To investigate whether menopause contributes to changes in body‐fat distribution, irrespective of aging or obesity.

The effects of physical exercise on body fat distribution and bone mineral density in postmenopausal women

OBJECTIVE The present cross-sectional study investigated the effects of physical exercise on body fat distribution and bone mineral density (BMD). METHODS Subjects were 57 postmenopausal women (mean age, 60.5+/-6.4 years) who had exercised regularly for at least 2 years. Controls were 130 age-matched sedentary women. Age, years since menopause (YSM), height, weight, and body mass index (BMI, wt./ht.(2)) were recorded. Total fat mass, percentage of body fat, trunk fat mass, leg fat mass, the ratio of trunk fat mass to leg fat mass (trunk-leg fat ratio), total body lean mass, percentage of body lean, and lumbar spine BMD (L2-L4) were measured by dual-energy X-ray absorptiometry. RESULTS Baseline characteristics and leg fat mass did not differ between the two groups. Total fat mass, percentage of body fat, trunk fat mass, and trunk-leg fat ratio were lower (P<0.05, P<0.01, P<0.01 and P<0.001, respectively), while total body lean mass, percentage of body lean mass, and lumbar spine BMD were higher in exercising women (P<0.05, P<0.05 and P<0.01, respectively). Performing physical exercise was inversely correlated with trunk-leg fat ratio (standardized regression coefficient=-0.178, P<0.01), but positively correlated with BMD (0. 203, P<0.01) irrespective of age, height, YSM, and total fat mass. CONCLUSION Physical exercise has beneficial effects on body fat distribution and BMD in postmenopausal women. Reduction of upper body fat distribution with physical exercise may be more attributable to the decrease in trunk fat mass.

Lean mass as a significant determinant of regional and total body bone mineral density in premenopausal women

Abstract: We investigated the relations of body composition to regional and total body bone mineral density (BMD) in 275 healthy Japanese premenopausal women (mean age, 37.1 ± 9.2 years; range, 16–55 years). In all subjects, the right side was dominant. BMD of the head, bilateral arms, lumbar spine (L2–L4), bilateral legs, and total body were measured using whole-body scanning by dual-energy X-ray absorptiometry (DXA). Total fat mass, total lean mass, regional lean mass, and regional fat mass were measured by DXA. Baseline characteristics including age, height, body weight, and body mass index were recorded for each subject. Possible correlations between regional or total body BMD with variables were determined on univariate and stepwise multiple regression analysis. BMD, lean mass, and fat mass were compared between the bilateral extremities. Total lean mass for the right arm, regional lean mass for the left arm, total lean mass for the lumbar spine, body weight for the bilateral legs, and total lean mass for the whole body were the most significant determinants of BMD on stepwise multiple regression analysis. Right-arm BMD was significantly higher than left-arm BMD. However, no significant difference was observed between BMD in the right and left legs. We concluded that lean mass is a more significant determinant of regional and total body BMD than fat mass in premenopausal women.

Bone mineral density in postmenopausal women with endometrial cancer

OBJECTIVE The aim of the study was to investigate the relationship between endometrial cancer and bone mineral density (BMD). MATERIALS AND METHODS A total of 55 postmenopausal Japanese women with well-differentiated adenocarcinoma and 284 age-matched healthy women were studied. Baseline characteristics including age, age at menopause, years since menopause (YSM), weight, height, body mass index (BMI), prior menstrual history, parity, and fertility were recorded for each subject. Lumbar spine BMD (L2-4), and body fat indices including body fat mass amount and percent body fat were measured by dual-energy X-ray absorptiometry. These variables were compared between the two groups. In all subjects (n = 339), correlations of BMD with the presence of endometrial cancer, baseline characteristics, and body fat indices were investigated, using univariate and multiple regression analyses. RESULTS BMD, weight, BMI, body fat mass amount, and percent body fat were significantly higher in women with endometrial cancer. Other baseline characteristics did not differ between the two groups. Age at menopause, height, weight, BMI, percent body fat, and body fat mass amount were positively correlated with BMD, while age and YSM were inversely correlated with BMD. After adjusting for age, YSM, and height, the presence of endometrial cancer was still correlated with BMD (P < 0.05). However, after adding body fat mass amount to these three adjusted variables, there was no correlation between the presence of endometrial cancer and BMD. CONCLUSION Women with endometrial cancer have a high BMD. This is attributable to high body fat mass amount in this disease.

Changes in endometrial wave-like movements in accordance with the phases of menstrual cycle.

To investigate whether endometrial wave‐like movements change with phases of the menstrual cycle.

Association of upper arm circumference at muscle flexion with lumbar spine bone mineral density

Abstract: We investigated the association of upper arm circumference at muscle flexion with lumbar spine (L2–L4) bone mineral density (BMD) in 252 postmenopausal Japanese women (mean age, 62.0 ± 7.6 years; range, 43–78 years) with right-side dominance. Age, age at menopause, years since menopause (YSM), weight, and height were recorded. Dominant upper arm circumference (cm) was measured at muscle flexion. Lumbar spine BMD was measured by dual-energy X-ray absorptiometry (DXA). Correlations between BMD and variables were determined using Pearsons correlation coefficient. Significant predictors of the lumbar spine BMD were determined using stepwise multiple regression analysis. Upper arm circumference, weight, and height were positively correlated with BMD (r = 0.397, 0.343, and 0.323, respectively), whereas YSM and age were inversely correlated with BMD (r = −0.415 and −0.392, respectively). On stepwise multiple regression analysis, YSM, upper arm circumference, and weight were significant predictors of BMD (R2 = 0.322, P < 0.0001). Predicted value of the lumbar spine BMD was calculated by the following formula: Predicted BMD = 0.249 − 0.0078 (YSM) + 0.016 (upper arm circumference) + 0.0046 (weight). Dominant upper arm circumference at muscle flexion in combination with YSM and weight is a useful predictor of lumbar spine BMD.