Nationwide Trends in the Incidence and Fatality of Acute Myocardial Infarction and Stroke in Korea, 2011-2023.

BACKGROUND AND OBJECTIVES: In South Korea and other countries operating national health insurance, claims data are used to estimate the burden of acute myocardial infarction (AMI) and stroke. However, most previous studies relied on diagnostic claim codes and did not distinguish first-ever from recurrent events. To estimate nationwide trends in the incidence and fatality of AMI and stroke using validated claims-based algorithms that distinguish first-ever from recurrent events. METHODS: We analyzed National Health Insurance Service (NHIS) claims data covering the entire Korean population from 2002 to 2023. The period from 2002-2010 served as a washout period, and annual incidence and case-fatality rates were estimated for 2011-2023. AMI (ICD-10: I21-I23) and stroke (ICD-10: I60-I61, I63-I64) events were identified from hospitalization episodes using diagnostic, procedure, imaging, and mortality codes. Crude and age-standardized rates were calculated. RESULTS: Between 2011 and 2023, AMI events increased from 22,395 to 34,768, including 1,472 to 3,373 recurrent cases. Stroke events rose from 99,837 to 113,098, including 16,925 to 22,813 recurrent cases. Crude incidence increased for AMI (44.7 to 68.0 per 100,000 person-years) and stroke (199.2 to 221.1), whereas age-standardized incidence increased slightly for AMI (35.7 to 37.1) but declined markedly for stroke (158.3 to 113.2). AMI fatality rates remained stable, whereas stroke fatality rates declined initially but rose modestly in recent years. CONCLUSIONS: By linking NHIS claims with mortality statistics and applying validated algorithms, this study demonstrates that reliable national monitoring of AMI and stroke incidence and fatality is feasible without extensive hospital-based registries or active surveillance systems.