Study of bone mineral density in resident doctors working at a teaching hospital

Context : The erratic lifestyle of resident doctors may affect their serum 25-hydroxy vitamin D [25-(OH)D] levels and bone mineral density (BMD). Aim : To study BMD and the effect of environmental factors on it in resident doctors. Settings and Design : Prospective, cross-sectional study conducted in a tertiary healthcare centre. Materials and Methods : BMD was obtained by dual-energy X-ray absorptiometry and was correlated with various factors including weight, height, body mass index (BMI), sun exposure, physical activity, parathyroid hormone, 25-(OH)D, dietary factors. Statistical Analysis : SPSS software Version 10 (Unpaired t test was used to compare BMD of different groups and Pearson′s correlation coefficient was used to calculate correlation). Results : Two hundred and fourteen apparently healthy resident doctors were enrolled in the study. Based on Caucasian normative data, osteopenia was noted in 104 (59.7%) males and 27 (67.5%) females. Thirty-two (18.39%) males and five (12.5%) females had osteoporosis. The BMD values of males were 0.947±0.086, 0.911±0.129 and 1.016±0.133 at lumbar spine, femur neck and total hip while those in females were 0.981±0.092, 0.850±0.101 and 0.957±0.103 respectively. BMD of our cohort was lesser by 12.5-18.2% and 4.2-14.5% than the Caucasian and available Indian figures, respectively. BMD had significant positive correlation with weight, height, BMI, physical activity, and dietary calcium phosphorus ratio. 25-(OH)D levels were insufficient in 175 (87.5%) subjects but had no correlation with BMD. Conclusions : Young healthy resident doctors had significantly lower BMD, contributors being lower BMI, lower height, reduced bioavailability of dietary calcium and inadequate physical activity. Deficiency of vitamin D did not contribute to low BMD.