Association between Korean Medicine Hospital Utilization and Cardiovascular Risks in Patients with Hypertension: a National Korean Cohort Study

Objectives: This study aims to investigate the effects of Korean Medicine Hospital Utilization (KMHU) on major adverse cardiovascular events (MACE), myocardial infarction (MI), stroke, and death in hypertensive patients taking antihypertensives. Methods: Using the Korean National Health Insurance Service-National Sample Cohort database, this study identified and diagnosed 68,457 hypertensive patients taking antihypertensives between 2003 and 2006. They were divided into KMHU and non-KMHU groups. The follow-up period ended with the diagnosis of myocardial infarction, stroke, or death. After propensity score matching (PSM), there were 18,242 patients each in the non-KMHU and KMHU groups. We calculated the incidence rate, hazard ratio (HR), and 95% confidence interval (CI) for MACE, myocardial infarction, stroke, and death in patients with hypertension using a stratified Cox proportional hazard model. In addition, secondary outcome analyses for stroke and cardiovascular mortality were performed. Results: After PSM, the HRs for MACE (HR: 0.84, 95% CI: 0.81-0.87), all-cause mortality (HR: 0.75, 95% CI: 0.72-0.79), and myocardial infarction (HR: 0.90, 95% CI: 0.83-0.97) were significantly lower in the KMHU group than in the non-KMHU group. Moreover, the HRs for stroke-related mortality, haemorrhage and ischaemic stroke-related mortality, and ischaemic heart disease-related and circulatory system disease-related mortality were significantly lower in the KMHU group than in the non-KMHU group. Conclusions: On long-term follow-up observation, this study supported the effect of KMHU for managing hypertension and reducing the burden of cardiovascular diseases.