Categorization of comorbidity profile of patients with myocardial infarction and impact of comorbidity profile on survival

Acute myocardial infarction (MI) is a common cardiac emergency with substantial morbidity and mortality. Approximately 550,000 first episodes and 200,000 recurrent episodes of acute MI occur in the United States of America annually. Ischemic heart disease is the leading contributor to the burden of disease regarding disability-adjusted life-years worldwide. Although the management of acute myocardial infarction has improved dramatically over the past decades, patients’ comorbidity burden is still important for outcome and especially for survival. In this context, Charlson Comorbidity Index is an established tool to evaluate patients’ individual comorbidity profile and to analyse the comorbidity profile-related impact on survival.

The objective of the present study is to investigate the impact of the comorbidity profile on prognosis of MI patients in a large nationwide inpatient sample.

The German nationwide inpatient statistics of the years 2005-2022 was used for statistical analysis of the MI patients (source: RDC of the Federal Statistical Office and the Statistical Offices of the federal states, DRG Statistics 2005-2022, and own calculations). Hospitalizations of MI patients were stratified for Charlson comorbidity class. The patients were categorized in mild severity (Charlson Comorbidity Index 1-2 points), moderate severity (Charlson Comorbidity Index 3-4 points) and severe severity (Charlson Comorbidity Index >4 points) and the severity classes were compared.

Overall, 4,913,273 hospitalizations of MI patients were counted in Germany between 2005 and 2022. Hospitalizations of MI patients were stratified by the Charlson Comorbidity Index class. Among these, 642,355 (13.1%) were categorized as mild, 1,263,564 (25.7%) as moderate, and 3,007,354 (61.2%) as patients with a severe comorbidity burden. In-hospital case-fatality increased with the current Charlson Comorbidity Index class: 2.8% in mild, 5.5% in moderate and 16.5% in the severe Charlson Comorbidity Index class (P<0.001). The Charlson Comorbidity Index class was significantly associated with increased in-hospital case-fatality (OR 2.974 [2.956-2.992], P<0.001).

The results of our study help to better understand the role of an aggravated comorbidity profile on increased in-hospital case-fatality of MI patients. An increase in the Charlson Comorbidity Index class by one was associated with an approximately 3-fold increase regarding in-hospital case-fatality.