Trends in Incidences, Treatments and Outcomes of Spontaneous Subarachnoid Hemorrhage in Korea Between 2002 and 2022.

Background: Access to equitable care for severely emergent diseases serves as a key indicator for evaluating the performance of a country's health care system. The aim of this study was to examine trends in the incidence, treatment and outcomes of patients with spontaneous subarachnoid hemorrhage (SAH) using Korean national claims data.

Methods: A retrospective analysis was conducted on a cohort of inpatients with spontaneous SAH from 2002 to 2022, utilizing data from the Korean National Health Insurance Service. The primary outcomes assessed were fatalities within 30 and 90 days from the index date of hospitalization.

Results: While the crude incidence rate has remained constant, the age-standardized incidence rate (ASR) has decreased from 22.0 per 100,000 in 2002 to 12.5 per 100,000 in 2022. The regions with the highest incidence rates were Gyeonggi (29,833 cases, 21.0%) and Seoul (26,484, 18.7%). In 2002, 59.6% of all patients received major treatments within 48 hours of admission, with a distribution of 68.4% in tertiary hospitals and 30.7% in secondary hospitals. By 2022, the proportion of patients receiving major treatment had increased to 71.9%, with 42.3% in tertiary hospitals and 57.5% in secondary hospitals. Endovascular coiling surpassed surgical clipping as the predominant treatment modality between 2013 and 2014. On average, 70.1% of treated patients received care within their area of residence, with the highest rates in Daegu (92.9%), Gwangju (91.4%) and Busan (90.1%) and the lowest in Jeonnam (14.2%). From 2002 to 2019, the 30-day and 90-day fatality rates declined from 21.2% to 19.2% and from 24.4% to 21.3%, respectively, whereas these rates gradually increased after 2020.

Conclusion: The total number of patients with spontaneous SAH remained relatively constant, whereas both the ASR and overall crude fatality rate declined. A national shift in treatment modalities was observed, with coiling surpassing clipping and admissions to secondary hospitals exceeding those to tertiary hospitals. Regional disparities in health care utilization were identified, highlighting the need for a locally accountable health care system in health care policy.