Age, Weight and Body Mass Index Effect on Bone Mineral Density in Postmenopausal Women

Post-menopausal osteoporosis: do body composition, nutritional habits, and physical activity affect bone mineral density?

Introduction

Aim: to evaluate the effect of body composition, nutritional habits (NH), and physical activity (PA) levels on bone mineral density (BMD) in osteoporotic postmenopausal women (OPW). Subjects and method: the demographic characteristics, anthropometric measurements, PA status, information on NH, some biochemical findings, and BMD measurements of 100 OPWs were evaluated. Results: in this study, 48 % of the women were classified as obese. The obese women were found to have lower vitamin D levels and higher parathyroid hormone levels than those of the over-weight women. A positive correlation was found between body mass index and L1L4, L2L4, and femur BMD (r = 0.268, p < 0.001; r = 0.241, p < 0.01; r = 0.369, p < 0.001, respectively). There was a significant decrease in L1L4 and femur BMD with increasing age (r = -0.224, p < 0.05; r = -0.366, p < 0.001, respectively). Femur BMD showed a positive correlation with duration (hours/week) and frequency of PA (days/week). According to the logistic regression analysis, body weight, daily tea consumption, and PA were positively associated with femur BMD, while advanced age, the age of menarche, salt and coffee consumption, and postmenopausal fracture status were negatively associated. Conclusion: we observed that body weight, some nutritional factors, and active lifestyle have seemed to effect BMD in OPWs. An adequate, balanced nutrition maintaining the ideal weight, and regular physical activity may improve bone health in OPWs.

A study on bone mass density using dual energy X-ray absorptiometry: Does high body mass index have protective effect on bone density in obese patients?

Background:

Osteoporosis is known as reduction of bone density, which is diagnosed using dual-energy X-ray absorptiometry. Although some studies have shown high body mass index (BMI) as a protective factor for osteoporosis and fracture risks, some other studies demonstrated obesity as a risk factor for osteoporosis. The aim of this study is to evaluate the relationship between BMI and bone mineral density (BMD) in premenopausal and postmenopausal females. Furthermore, we determined the correlation between BMI and fracture risk in postmenopausal females.

Materials and Methods:

In this study, we evaluated the relationship between the age and BMI with 10-year probability fracture risk (estimated using fracture risk assessment tool) and BMD in the L1–L4 spine and femoral neck. Data were collected from BMD center, Askariye Hospital, Isfahan, Iran, from May 2016 to July 2017.

Results:

The study consisted of 1361 individuals, including 305 premenopausal females and 1056 postmenopausal females. The results showed a statistically significant increase of BMD (P < 0.001) and a decrease of fracture risk (β = −0.158, R² = 0.518) with an increase of BMI in postmenopausal females. Moreover, lumbar spine and femoral neck BMD were significantly higher in individuals with BMI ≥30 than in those with BMI <25 in both premenopausal and postmenopausal females (P < 0.001). In addition, older postmenopausal females indicated significantly lower L1–L4 BMD (r = −0.280, P < 0.05) and femoral neck BMD (r = −0.358, P < 0.05).

Conclusion:

The results showed a positive correlation between BMI and BMD of the spine and femoral neck which did not differ by menopausal status. However, there was a correlation between BMI and fracture risk in postmenopausal females.