[Factors associated with the implementation of municipal osteoporosis screening: An ecological study]

Objectives　In Japan, in accordance with their public health responsibilities to promote the early detection and treatment of osteoporosis, municipal governments are legally encouraged to implement osteoporosis screening. However, the proportion of municipalities that conduct such screenings plateaued at approximately 60%, with substantial intermunicipal disparities. In this study, we aimed to identify the factors that are associated with the implementation of osteoporosis screening across all municipalities in Japan.Methods　This ecological study included all municipalities in Japan. Based on the 2022 Community Health and Health Promotion Project Report, public data on fiscal factors, population characteristics, and medical resources were analyzed to ascertain the implementation status of osteoporosis screening. The community environmental indicators included the habitable population density, area-deprivation index, and rurality index. Modified Poisson regression was used to estimate prevalence differences (PDs) with 95% confidence intervals (CIs). The multivariable model comprised all explanatory variables, except the number of orthopedic surgeons and the rurality index which were excluded owing to their strong correlations with the other variables.Results　Among 1,735 municipalities, 1,094 (63.1%) implemented osteoporosis screening. In the unadjusted model, a 0.1-unit increase in the fiscal capacity index was associated with a 1.2 percentage-point higher implementation rate (PD＝0.012, 95% CI [0.004-0.020], P＝0.003). In contrast, a 1% increase in the proportion of residents aged ≥75 years was associated with a 0.6 percentage-point lower implementation rate (PD ＝－0.006, 95% CI [－0.011 to －0.002], P＝0.004), and a one-unit increase in the area-deprivation index was associated with a 3.7 percentage-point lower rate (PD＝－0.037, 95% CI [－0.072 to －0.003], P＝0.032). In the multivariable model, the fiscal capacity index remained positively associated with osteoporosis screening implementation, with a 0.1-unit increase corresponding to a 1.7-percentage point higher implementation rate (PD＝0.017; 95% CI [0.003-0.030], P＝0.014). In contrast, a 10% increase in the habitable population density was associated with a 0.4-percentage point decrease in the implementation rate (PD＝－0.004, 95% CI [－0.006 to －0.001], P＝0.005).Conclusion　A greater fiscal capacity and a higher habitable population density were associated with higher and lower implementation rates of osteoporosis screening, respectively. Thus, local socioeconomic and geographic characteristics may influence municipal-level screening practices; these findings provide evidence for developing strategies to promote the implementation of osteoporosis screening and reduce disparities among municipalities.