Material and Method: This cross-sectional investigation recruited 779 Thai women between 20 and 85 years. Lumbar spine and hip BMD was measured by DXA (Osteosys Dexxum-T). The BMD results were classified by T-score as per WHO criteria.

Results: Advancing age was negatively correlated with BMD at both sites, whereas body weight was positively correlated to BMD at both. The correlation between BMDs at the lumbar spine and hip was 0.67 to 0.69. The peak BMD was observed in women between 20 and 24 years at both sites, with a respective mean and standard deviation of 1.082±0.153, 1.115±0.161, 0.878±0.150, and 0.946±0.125 at L1-4, L2-4, the femoral neck and total hip. Using the Thai references derived from peak BMD, the prevalence of osteoporosis was 5.1 to 5.5 and 3.1 to 6.3% at the lumbar spine and hip, respectively, which was lower than the Asian reference as provided by DXA.

Conclusion: The present study suggested that using the T-score provided by the Osteosys Dexxum-T over-diagnosed osteoporosis in Thai women. The authors recommend using Thai normal reference from the present study to define the BMD result in Thai women.

Keywords: Bone mineral density, Dual energy x-ray absorptiometry, Osteoporosis, Reference, Thailand