The effect of body mass index on bone mineral density in postmenopausal women

Obesity and osteoporosis are very common disorders and they both have high cost of treatment. Diseases such as cardiovascular diseases, diabetes, high blood pressure and degenerative joint disorders are more common in the setting of obesity. On the other hand, osteoporosis, due to increased fracture risk, is a common culprit of morbidity and mortality in geriatric population. The aim of the study was to analyze the possible relationship between body weight and bone quality in postmenopausal women. 121 patients between 47-80 age who were at least 1 year postmenopausal that applied to Government Hospital Of Rize, Department Of Physical Therapy and Rehabilitation were recruited for our study. Women with surgical menopause, women with medical problems known to effect bone mineral density, and women who are being treated for osteoporosis were excluded from the study. Age, weight, height, years after menopause, number of children, previous history of fracture and bone mineral density (BMD) measured from the lumbar vertebrae (L1-L4) were recorded. Based on body mass index (BMI) measurements using the World Health Organisation (WHO) criteria, 6 ( 5%) of the patients had a normal BMI, 27 (22.3%) were overweight, 39 (32.2%) patients were grade 1 obese , 29 (%24) of the patients had grade 2 obesity and 20 (%16.5) patients had grade 3 obesity. There was a statistically significant positive relationship between BMI and BMD (r=0.41, p=0.0001) and BMI and T-score (r=0.31, p=0.001). In conclusion, body weight has a positive effect on bone mass and it is possible to claim that obesity is protective against osteoporosis.