The impact of basic vs private health insurance status on treatments and outcomes of ST-elevation myocardial infarction patients in Switzerland: insights from the AMIS Plus registry

BACKGROUND: Large disparities in treatments and outcomes of ST-elevation myocardial infarction (STEMI) patients driven by insurance status have been reported. However, it is unknown whether this applies to Switzerland, a country characterised by an overall high income, mandatory basic health insurance covering virtually all treatments and the option of a supplementary private health insurance allowing for full institution and doctor choice as well as a higher service standard. This study aimed to assess the impact of insurance status on treatments and outcomes in STEMI patients in Switzerland. METHODS: STEMI patients enrolled in the nationwide Acute Myocardial Infarction in Switzerland (AMIS) Plus registry between 2005 and 2023 were analysed. We compared patients with basic health insurance only to those with supplementary private health insurance with respect to optimal medical therapy, percutaneous coronary intervention (PCI) and outcomes. Primary outcome measures were rates of optimal medical therapy and full guideline-recommended treatment (FGRT) (defined as optimal medical therapy plus PCI). Secondary outcome measures were in-hospital all-cause mortality, major adverse cardiac and cerebrovascular events (MACCE), length of stay and 1-year all-cause mortality after discharge. Multivariate logistic mixed-effects models examined whether insurance type influenced treatments and outcomes. RESULTS: Among 16,463 patients, 13,023 (79.1%) had only basic health insurance. Patients with basic health insurance only were younger, more often males and had higher rates of obesity, diabetes and active smoking, but lower rates of cancer than supplementary private health insurance patients. In addition, they more often received optimal medical therapy and FGRT. Patients with basic health insurance only had higher rates of in-hospital mortality and MACCE. However, after adjusting for covariates, no statistically significant associations were identified between insurance type and access to optimal medical therapy or FGRT, in-hospital mortality, MACCE, length of stay or 1-year mortality after discharge. CONCLUSION: In this study, we observed no significant association between insurance status and treatments or outcomes of STEMI patients, suggesting a high level of equity in acute cardiac care in Switzerland.