A Comparative Study of Bone-Health and Associated Factors in Healthy Indian Adolescents and Young Women.

Introduction: Adolescence is a critical period for the accrual of bone mass. However, few studies have assessed the bone geometry in slum-dwelling girls/young women. We thus conducted this study: (1) to assess bone health in Indian adolescent girls and young women residing in slum vs nonslum (NS) areas and (2) to identify factors associated with poor bone health.

Methods: This cross-sectional case-control study was performed on 110 apparently healthy unmarried, nonpregnant, nonlactating, postmenarchal adolescent girls and young women aged 11 to 24 years residing in urban slums with the same number of age-matched controls from NS areas. Anthropometric, dietary, physical-activity and bone-health parameters (using dual-energy X-ray absorptiometry and peripheral quantitative computed tomography-DXA and pQCT-respectively) were evaluated using standard protocols. A P value of < 0.05 was considered statistically significant.

Results: Slum girls were significantly shorter and lighter and had lower dietary intakes of calcium and protein after adjusting for total daily calorie intake than NS girls (P < 0.05). Areal bone-mineral density (BMD) at lumber spine (0.940 ± 0.13 vs1.042 ± 0.15 g/cm²), femur and total body (less-head), bone-mineral apparent density adjusted for volume at the lumbar spine (0.295 ± 0.04 vs 0.319 ± 0.04 g/cm³) and height-adjusted bone density at femur (0.862 ± 0.011 vs 0.905 ± 0.011 g/cm²) were significantly lower in slum dwelling participants as compared to their NS counterparts (P < 0.05). After adjusting for confounders like sunlight exposure, anthropometric parameters and dietary calcium intake, area of dwelling was still a significant factor for the difference in BMD.

Conclusions: The potential determinants of poor bone density and geometry in girls and young women residing in slums include residential location, dietary habits, and physical activity levels. Despite adjustments for confounding factors, differences in bone health between those in slum and nonslum areas suggest adaptations developed over generations of deprivation in these individuals, necessitating urgent intervention.