Objective: To assess the prevalence and the relative importance of risk factors for low bone mass in Indian pre- and post-menopausal women.
Methods: Data were collected on anthropometry and lifestyle factors in apparently healthy 80 pre- and 92 post-menopausal (40-75 years) women. Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry. Fasting blood samples were analysed for Parathyroid hormone, vitamin D, calcium and zinc.
Results: BMD at all three sites was significantly lower in post-menopausal than the pre-menopausal women (p < 0.001). Prevalence of osteoporosis was highest at the lumbar spine (25.8%) in post-menopausal women, while prevalence of osteopenia was high in pre-menopausal women (44.3%). Vitamin D deficiency was seen in 54.5% pre and 41.8% post-menopausal women and significant correlation of serum 25(OH)D levels (r = 0.16) was obtained only for total hip Z-score (p < 0.05). Correlation between sun index and lumbar spine BMD was marginally significant (r = 0.14, p = 0.07). Generalised linear models revealed that after adjusting for age, weight and height, percent decrease of 2.1-4.5% in BMD may be attributed to menopause.
Conclusion: Age, weight, height, menopause, low intakes of calcium and low 25(OH)D along with poor sunlight exposure are the major factors contributing to bone loss in Indian women above 40 years of age.