Disparities in sleep medicine in Japan: association between CPAP prescriptions and the number of certified sleep medicine providers.

PURPOSE: Health disparities in sleep medicine are associated with underdiagnosis and undertreatment of sleep disorders, despite their well-established impact on health. This study aims to clarify regional disparities in continuous positive airway pressure (CPAP) therapy prescriptions across prefectures in Japan and to examine the association between the number of sleep specialists and CPAP prescription rates.

METHODS

This is an ecological study, investigating the association between the number of sleep specialists and CPAP insurance claims across 47 Japanese prefectures, using publicly available open data. Multiple linear regression was used to assess the impact of sleep specialists on CPAP prescriptions, adjusting for covariates such as proportion of population aged 65 and over, obesity rates, and heart disease prevalence.

RESULTS

The number of CPAP insurance claims per 1,000 population ranged from 35.0 to 65.3, with a 1.87-fold variation. The number of sleep specialists per million population varied substantially, from 0 to 35.8. Multivariable regression analysis revealed that the number of CPAP prescriptions was significantly associated with the number of sleep specialists (β = 0.32, B = 0.37, 95% CI: 0.04-0.71, p = 0.03), and the prevalence of heart disease (β = 0.39, B = 561.9, 95% CI: 55.7-1068.2, p = 0.03).

CONCLUSION

The present study showed regional disparities in sleep medicine in Japan and a positive association between the number of sleep specialists and CPAP prescriptions, which highlighted the importance of enhancing the certification systems for sleep specialists to address regional health inequities in sleep medicine.