Resting energy expenditure: a stronger marker than body weight for bone mineral density in white women but not men? The Rancho Bernardo study

Screening for basal metabolic rate and visceral fat among postmenopausal osteoporosis with type 2 diabetes mellitus

BACKGROUND

In people with type 2 diabetes mellitus, there is an increase in basal metabolic rate (BMR) which is associated with level of glycaemic control. Women with postmenopausal osteoporosis have decreased BMR. The aim of the present study is to find the BMR using Meffin-St Jeor predictive equation in women with type 2 diabetes mellitus (T2DM) who have attained menopause with osteoporosis.

MATERIALS & METHODS

100 women who have attained menopause, who were diagnosed to have osteoporosis with type 2 diabetes mellitus were assessed for BMR using Meffin-St Jeor predictive equation. Detailed history of diabetes and menopause were obtained. Blood glucose value was measured using standard glucometers. Body composition for visceral fat (VF) was measured using bioelectrical impedance analysis. Level of physical activity of the participants was measured using global physical activity questionnaire (GPAQ).

RESULTS

The median BMR of the participants was 1.075 (714, 1483.25). Statistically significant correlation was found between BMR and GPAQ (r_s = 0.731), BMR and VF (r_s = 0.678). However BMR was not correlated with FBS (r_s = 0.083) duration of diabetes (r_s = -0.046).

CONCLUSION

There is a decrease in BMR in women with T2DM with postmenopausal osteoporosis. BMR was significantly correlated with level of physical activity and visceral fat.

Influence of basal energy expenditure and body composition on bone mineral density in postmenopausal women

Background

The aim of this study was to investigate the influence of body mass index, body weight, lean mass, fat mass, and basal energy expenditure on bone mineral density in postmenopausal women.

Methods

This was a cross-sectional, descriptive study of a sample of 50 women, with minimum time since menopause between 1 and 10 years. Bone mineral density was assessed at the lumbar spine (L2–L4), femoral neck, Ward’s triangle, and trochanter using dual-energy X-ray absorptiometry. Body mass index, lean mass, fat mass, and basal energy expenditure were measured by bioimpedance.

Results

The mean age of the women was 51.49 ± 3.86 years and time since menopause was 3.50 ± 2.59 years. Significant negative correlations were found between chronological age and lumbar spine, femoral neck, Ward’s triangle, and trochanteric bone mineral density. In regard to time since menopause, we also observed significant negative correlations with bone mineral density at the lumbar spine and Ward’s triangle. The following significant positive correlations were recorded: body mass index with bone mineral density at the femoral neck and trochanter; fat mass with bone mineral density at the femoral neck and trochanter; lean mass with bone mineral density at the lumbar spine, femoral neck, and trochanter; and basal energy expenditure with bone mineral density at all sites assessed. On the other hand, the multiple linear regression model showed that: 20.2% of bone mineral density variability at the lumbar spine is related to lean mass and time since menopause; 22.3% of bone mineral density variability at the femoral neck is related to body weight and age; 18.9% of bone mineral density variability at Ward’s triangle is related to age and basal energy expenditure; and 39% of bone mineral density variability at the trochanter is related to body mass index, age, and menarche.

Conclusion

Changes in bone mineral density, specific for each skeletal site, are influenced by age, time since menopause, body weight, body mass index, lean mass, and basal energy expenditure. Lean mass and basal energy expenditure positively influenced bone mineral density at the lumbar spine and Ward’s triangle, with a predominance of trabecular bone.

Percent body fat, fractures and risk of osteoporosis in women

OBJECTIVES

Globally, in an aging population, osteoporosis and fractures are emerging as major public health problems; accessible and affordable recognition, prevention and treatment strategies are needed. Percent body fat is known to be associated with bone mineral density and fractures. This paper uses an innovative, virtually cost-free method to estimate percent body fat from age, height and weight, and assesses its validity by examining the association between percent body fat and fractures among women 39 and older.

DESIGN

An epidemiologic study.

PARTICIPANTS

3940 college alumnae, median age 53.6, participated by responding to a mailed questionnaire covering medical history, behavioral factors, birth date, weight and height.

STATISTICAL METHODS

T-tests, chi-square and multivariable logistic regression.

MEASUREMENTS

Percent body fat estimated from age, weight, height and gender.

RESULTS

Associations of fractures with percent body fat are expressed as odds ratios: for osteoporotic (wrist, hip and/or x-ray confirmed vertebral), the adjusted OR = 2.41, 95% CI (1.65, 3.54), P < 0.0001; for wrist fractures, the adjusted OR = 2.56, 95% CI (1.65, 3.96), P < 0.0001; for x-ray confirmed vertebral fractures the adjusted OR = 4.69, 95% CI (2.05, 10.77), P=0.0003).; and for non-osteoporotic, he adjusted OR= 1.00, 95% CI (0.76 1.32), P=0.999.

CONCLUSION

The findings are consistent with methods using DXA and/or other technologies that show percent body fat is associated with fractures of the wrist and vertebrae. Identification of risk factors is necessary for the prevention and treatment of osteoporosis and osteoporotic fractures. Estimation of percent body fat from age, height and weight may be a valid, cost-saving, and cost-effective alternative tool for screening and assessing risk of osteoporosis in settings where Dual x-ray absorptiometry (DXA) or other radiological techniques are too costly or unavailable.