Reference Values for Bone Mineral Density and Bone Turnover Markers in the General Elderly Population: A Japanese Cohort Survey Randomly Sampled From A Basic Resident Registry

The aim of this study was to provide definitive reference values for bone mineral density (BMD) and bone turnover markers in the general elderly population. Registered citizens of 50 to 89 years old were targeted for this survey. After random sampling from the resident registry of Obuse town, we established eight groups based on age (50s, 60s, 70s, and 80s) and gender. A total of 411 people were enrolled. We used a dual-energy x-ray absorptiometry device to measure and evaluate BMD. The bone formation marker bone alkaline phosphatase (BAP) was measured as a bone turnover marker. Bone resorption markers, including pentosidine, urinary total deoxypyridinoline, urinary type I collagen N-telopeptide, tartrate-resistant acid phosphatase 5b (TRACP-5b), 25-hydroxyvitamin D, and whole PTH were also measured as bone turnover markers.Sixty-three people (15.3%) were diagnosed as OP. In women, BMD decreased with age. On the other hand, there was no characteristic change with age in men. As for bone markers, 25(OH)D, whole parathyroid hormone, and BAP showed no characteristics associated with gender and aging. In terms of the association between low BMD and bone markers, there was a significant association between low BMD and TRACP-5b in females.In conclusions, BMD decreased with age in women. However, there was no decline with age in men. All bone metabolism markers showed no significant characteristics associated with age or gender, except for a significant association between low BMD and TRACP-5b in females. TRACP-5b was a potentially useful marker for the detection of low BMD.