Impact of comorbidity burden on outcome in patients with cardiogenic shock: A Cardiogenic Shock Working Group analysis.

AIMS Comorbidity burden is a major determinant of outcomes. Its prognostic impact on cardiogenic shock (CS) across CS subtypes remains insufficiently characterized. We aimed to characterize the prevalence and distribution of comorbidities in CS, assess their impacts on outcomes, and identify high-risk comorbidity patterns in all-cause, acute myocardial infarction-related (AMI-CS) and heart failure-related CS (HF-CS). METHODS AND RESULTS Cardiogenic shock patients from the multicentre Cardiogenic Shock Working Group (CSWG) registry (2020-2024) were analysed. We used adjusted logistic regression models to assess the impact of comorbidities individually, in combination, and as a cumulative burden on in-hospital mortality. We developed the Comorbidity Risk Index for Cardiogenic Shock (COMRI-CS) to capture the association between comorbidities and CS mortality. Among 6815 patients (26.5% AMI-CS, 53.6% HF-CS), 6087 (89.3%) presented with ≥1 comorbidity, and 4390 (64.4%) with ≥3 comorbidities. In-hospital mortality increased with comorbidity burden (AMI-CS: 35.4%, 39.6%, 47.1% with 1-3, 4-6, ≥7 comorbidities, respectively; HF-CS: 19.6%, 24.9%, 27.5%, respectively). A high comorbidity burden was independently associated with a 51% higher relative mortality risk in AMI-CS (odds ratio [OR] 1.51, 95% confidence interval [CI] 1.02-2.23, p = 0.037), and a more pronounced increase of 122% in HF-CS (OR 2.22, 95% CI 1.49-3.37, p < 0.001). Distinct high-risk comorbidities and combinations were identified, varying across CS subtypes. With each COMRI-CS point, in-hospital mortality increased by ~5.5%. CONCLUSIONS In this large real-world CS cohort, comorbidity burden was highly prevalent, varied across subtypes, and was independently associated with mortality. Integrating chronic conditions into early CS risk stratification may enhance clinical decision-making in CS management.