Relation between Obesity and Bone Mineral Density and Vertebral Fractures in Korean Postmenopausal Women

Abstract

PurposeThe traditional belief that obesity is protective against osteoporosis has been questioned. Recent epidemiologic studies show that body fat itself may be a risk factor for osteoporosis and bone fractures. Accumulating evidence suggests that metabolic syndrome and the individual components of metabolic syndrome such as hypertension, increased triglycerides, and reduced high-density lipoprotein cholesterol are also risk factors for low bone mineral density. Using a cross sectional study design, we evaluated the associations between obesity or metabolic syndrome and bone mineral density (BMD) or vertebral fracture.Materials and MethodsA total of 907 postmenopausal healthy female subjects, aged 60-79 years, were recruited from woman hospitals in Seoul, South Korea. BMD, vetebral fracture, bone markers, and body composition including body weight, body mass index (BMI), percentage body fat, and waist circumference were measured.ResultsAfter adjusting for age, smoking status, alcohol consumption, total calcium intake, and total energy intake, waist circumference was negatively related to BMD of all sites (lumbar BMD p = 0.037, all sites of femur BMD p < 0.001) whereas body weight was still positively related to BMD of all sites (p < 0.001). Percentage body fat and waist circumference were much higher in the fracture group than the non-fracture group (p = 0.0383, 0.082 respectively). Serum glucose levels were postively correlated to lumbar BMD (p = 0.016), femoral neck BMD (p = 0.0335), and femoral trochanter BMD (p = 0.0082). Serum high density lipoprotein cholesterol (HDLC) was positively related to femoral trochanter BMD (p = 0.0366) and was lower in the control group than the fracture group (p = 0.011).ConclusionIn contrast to the effect favorable body weight on bone mineral density, high percentage body fat and waist circumference are related to low BMD and a vertebral fracture. Some components of metabolic syndrome were related to BMD and a vertebral fracture.

Obesity Increases Precision Errors in Dual-Energy X-Ray Absorptiometry Measurements

“…With the increasing incidence of obesity in the population [7,14] and recent evidence that there is a greater fracture incidence in obese patients [15,16] and lower than expected BMD in a sub-population of obese women [17], the larger precision errors in obese populations demonstrated in this study will be increasingly significant for clinical studies.…”

High cholesterol diet increases osteoporosis risk via inhibiting bone formation in rats

“…High cholesterol fed rats had higher body weights, which is consistent with the view that obesity is related wtih osteoporosis. Kim [20] showed that high percentage body fat and waist circumference correlated with low BMD and risk of a vertebral fracture. Obesity-reduced bone density was associated with activation of PPARgamma and suppression of Wnt/ beta-catenin in rapidly growing male rats [21] .…”

Bone Mineral Density in Relation to Metabolic Syndrome Components in Postmenopausal Women With Diabetes Mellitus Type 2

“…that obesity is not benefi cial or has a negative eff ect on osteoporosis. In a study of postmenopausal Korean women 19 , waist circumference, which provides an indication of central obesity (visceral fat mass), was related to low BMD and osteoporotic vertebral fractures. In contrast, our research demonstrated signifi cant positive correlation between vertebral and femoral BMD and waist circumference, which could be explained by higher circulating insulin levels in central obesity.…”