Poor bone health in underprivileged Indian girls: an effect of low bone mass accrual during puberty

A socio-economic gradient exists for most reasons of morbidity and mortality including delayed puberty in lower (LSES) as compared to higher (HSES) socio-economic stratum and puberty is an important factor affecting bone status in children and adolescents. Thus, a cross-sectional study was conducted on 195 age-matched pairs of girls (8-17years) from LSES and HSES in Pune City, India to assess the hypothesis that socio-economic factors working through late puberty would have a negative association with bone status of adolescents. Height, weight and Tanner stage were assessed. Total body bone mineral content (TBBMC), total body bone area (TBBA), total body bone mineral density (TBBMD), lean body mass (LBM) and total body fat mass (TBFM) were measured using GE Lunar DPX Pro Pencil Beam DXA (Wisconsin, USA) scanner. Mean TBBMC (1172±434g), TBBA (1351±356cm(2)), TBBMD (0.846±0.104g/cm(2)), LBM (21,622±5306g) and TBFM (7746±5194g) in LSES girls were significantly lower than that of HSES girls [TBBMC (1483±525g), TBBA (1533±380cm(2)), TBBMD (0.942±0.119g/cm(2)), LBM (24,308±5829g) and TBFM (12,196±7404g)] (p<0.01). There was a significant effect of age and puberty on all bone parameters. The differences in TBBMC, TBBA, LBM and TBFM between the 2 socio-economic strata at Tanner stage I were not significant (p>0.1) whereas there were significant differences in these parameters from Tanner stages II to V (p<0.05). The percentage difference between LSES and HSES girls in TBBMC, TBBA, TBBMD, LBM and TBFM was 3.4%, 0%, 3.7%, 0.2% and 17.3% respectively at Tanner stage I which increased to 19.1%, 9.7%, 10.4%, 8.8% and 31.2% respectively at Tanner stage V. In conclusion, our results suggest that pubertal years may provide a window of opportunity to promote bone health in adolescent girls from the lower socio-economic stratum.