The prevalence, incidence and burden of narcolepsy and idiopathic hypersomnia in Taiwan: comparison between the National Health Insurance Research Claims Database and a hospital cohort database.

Study objectives: We investigated the prevalence and incidence of narcolepsy (type 1 and 2) and idiopathic hypersomnia (IH) in Taiwan using the National Health Insurance Research Database (NHIRD), and compared disease burden with patients identified from a "gold-standard" hospital database.

Methods: This study employed retrospective cohort and cross-sectional designs, to analyze data from the NHIRD and the hospital database cohort between 2009 and 2019. Analyses comprised prevalence and incidence of narcolepsy and IH, with diagnoses validated against the hospital database, and comparison of demographics, prescriptions, comorbidities, healthcare utilization, and costs with a control cohort. Categorical variables were analyzed using the chi-squared test; continuous variables were assessed via analysis of variance or Kruskal-Wallis tests.

Results: From both databases, 24  317 patients were identified as having narcolepsy or IH. The diagnosed prevalence of narcolepsy was 9.98 per 100 000 individuals. Annual increases in prevalence and incidence were observed, particularly in young adults (aged 21-30 years). Patients with narcolepsy and IH exhibited higher rates of comorbidities and received more psychotropics compared with controls. However, fewer patients from the NHIRD received treatment for hypersomnolence than those from the hospital cohort. Healthcare utilization and costs were higher among patients with narcolepsy and IH compared with controls.

Conclusions: Increased narcolepsy prevalence over time was observed, particularly among young adults, but the overall prevalence in Taiwan appears to be lower than in other countries, potentially indicating underdiagnosis or inadequate treatment. High comorbidity rates and healthcare utilization underscore the substantial disease burden in patients with central hypersomnia.