Age- and modality-specific trends in bone mineral density testing among women in Japan.

Abstract

Osteoporosis affects an estimated 15.9 million people in Japan. Because diagnosis is based on bone mineral density (BMD), access to BMD testing is essential for fragility-fracture prevention; however, nationwide trends by modality and age have been unclear. We examined trends in BMD testing among women using the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB). Public NDB Open Data (fiscal years 2014-2022) were used to obtain annual counts of BMD examinations by age group and modality: dual-energy X-ray absorptiometry (DXA), microdensitometry/single-energy X-ray absorptiometry (MD/SXA), and quantitative ultrasound (QUS). Age-stratified population-adjusted rates were calculated using census data. Trends were assessed with Poisson regression with log(population) offsets and year-by-age interaction terms. Total examinations increased from 5.46 million (2014) to 7.14 million (2022). Women aged 60-69, 70-79, and 80-89 years accounted for >85% of tests. Population-adjusted rates increased across all age groups, with the largest annual increases in women aged 40-49 years and ≥90 years (∼4.4%/year). DXA increased from 1.67 to 4.03 million, whereas MD/SXA decreased from 3.18 to 2.67 million. QUS decreased overall (608,118 to 434,984) but increased in women aged ≤39 and 40-49 years. BMD testing among women in Japan expanded and shifted toward DXA, with declining MD/SXA and selective growth of QUS in younger women, supporting the need for age- and context-appropriate diagnostic strategies.