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

Abstract

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.

Keywords: Hemorrhagic Stroke; Korea; SAH Fatality; SAH Incidence; SAH Treatment; Spontaneous Subarachnoid Hemorrhage (SAH).

Fig. 1. Flowchart of the study population selection.

SAH = spontaneous subarachnoid hemorrhage, NHIS = National Health Insurance Service.

Fig. 2. Number of patients with spontaneous subarachnoid hemorrhage by year, type of health care institution, and type and location of health care institution from 2002 to 2022. (A) The number of patients. (B) Crude and age-standardized incidence rates. (C) The number of patients by type of health care institution. (D) The number of patients by type and location of health care institution.

AAPC = average annual percent change, ER = emergency room, ICU = intensive care unit.

Fig. 3. Number of treated patients with spontaneous subarachnoid hemorrhage according to the type of treatment modality from 2002 to 2022. (A) The number of patients during 2 weeks of hospitalization. (B) The number of patients within 48 hours of admission.

BHT = burr-hole trephination, EVD = extraventricular drainage, DC = decompressive craniectomy.

Fig. 4. Number of patients with spontaneous subarachnoid hemorrhage who received either coiling or clipping within 48 hours of admission by type of health care institution from 2002 to 2022.

AAPC = average annual percent change.

Fig. 5. The 30- and 90-day fatalities of spontaneous subarachnoid hemorrhage patients annually from 2002 to 2022. (A) Overall fatality. (B) The 30-day fatality according to the type of treatment modality. (C) The 90-day fatality according to the type of treatment modality. (D) The 30-day fatality rates by type of health care institution. (E) The 90-day fatality by type of health care institution. (F) The 30-day fatality rate according to the type and location of health care institution. (G) The 90-day fatality rates according to the type and location of health care institution.

AAPC = average annual percent change, BHT = burr-hole trephination, EVD = extraventricular drainage, DC = decompressive craniectomy.