Is high bone mass index protective for osteoporosis? ‘Evaluation of relationship between body mass index, and bone mineral density in the population of the Himalayan region of India

Abstract

Objective: Although several studies have done for relationship between obesity and bone mineral density (BMD), the results are inconclusive. The aim of this study was to further investigate the relation between age, weight, BMI and BMD in outpatients of Himalayan region. Materials and methods: A hospital based cross sectional study was conducted on patients attending the outpatient Department of Orthopaedics of Shri Mahant Indiresh Hospital for a period of 3 years from September 2014 to September 2017. A total no. of 232 patients (198 F+ 34M) in the age group of 30 -90 years were selected randomly for the study. Exclusion criteria were age less than 30 and more than 90 years, confirmed cases of osteoporosis, patients on antiresorptive treatment, cases of surgically removed ovary and uterus, bone metastasis. Dual Energy X-ray Absorptiometry (DXA) scans were obtained to assess presence of low BMD. BMI calculations and BMD T-Score at femoral neck were done in all patients. Participants were categorized in BMI group (underweight <18.5 kg/m 2 , normal weight ≤25.0 kg/m 2 , overweight BMI ≥ 25 kg/m 2 and obese ≥ 30 kg/m 2. ) and BMD groups (normal < -1, osteopenia -1 to < -2.5, osteoporosis ≥ -2.5 and severe osteoporosis > -3). Statistical Package for Social Sciences (SPSS) version 20 was used for statistical analysis. Results: Subjects with higher Bone Mass Index were having high bone mineral density and less prone for osteoporosis. It was also evident that subjects in the higher age group were more prone of having osteoporosis. So it can be concluded that Body Mass Index and BMD showed a positive correlation, whereas, advancing age is associated with low BMD.