Bone mass density in the normal population of Iran

Abstract: Background: Bone mineral density (BMD) of the spine and the femoral neck are accurate indicators of the bone mass and thus useful predictors of fracture risk. Dual energy X-ray absorptiometry (DEXA) is the easiest, yet the most precise and non-invasive technique. The need for a population-specific normative BMD data is vital in preventing mislabelling or misdiagnosis of osteopenia or even osteoporosis. Aim: This study was performed to determine the lumbar vertebral and the proximal femur BMD measured by DEXA in 280 normal Iranian men and women. Method: Subjects were selected randomly from different social economic classes in Tehran. Normal subjects were selected for each decade and both sexes. BMD was measured with a Hologic QDR 1000+ densitometer, for the lumbar spine (L1, L2, L3, L4, L1–L4) and the femoral neck (neck, trochanter, intertrochanter, ward triangle, total). Data were treated by polynomial approximation (3rd degree). Results: In women, the highest BMD recorded was 1.020 g/cm2 for the lumbar spine (mean L1–L4) at the age of 31 years, and 0.832 for the femoral neck at the age of 34. In men, the highest BMD recorded was 0.987 g/cm2 for the lumbar spine (mean L1–L4) at the age of 36, and 0.907 for the femoral neck at the age of 30. The highest BMD in spine was lower in men than women. Conclusion: The BMD of both lumbar spine and femoral neck (in both sexes) was lower in this study than the Hologic standards. Key words: bone mineral density, dual energy X-ray absorptiometry (DEXA), osteoporosis.