1Universitätsklinikum Mannheim I. Medizinische Klinik Mannheim, Deutschland; 2Klinikum Nürnberg Nord Institut für klinische Chemie und Laboratoriumsmedizin und Transfusionsmedizin Nürnberg, Deutschland; 3Medizinische Hochschule Hannover Kardiologie und Angiologie Hannover, Deutschland
Objective: The study investigates the prevalence and prognostic impact of anemia in a cohort of patients with coronary artery disease (CAD), as well as procedural data and outcomes in unselected patients undergoing invasive coronary angiography (CA).
Background: The spectrum of patients undergoing CA has significantly changed over the past decades, related to ongoing demographic changes and improved treatment strategies for patients with cardiovascular disease. Limited data regarding anemia-related characteristics and outcomes in unselected patients undergoing CA is available.
Methods: Consecutive patients undergoing invasive CA from 2016 to 2022 were included at one institution. Patients with anemia (hemoglobin <13.0 g/dL for males and <12.0 g/dL for females) were compared to patients without anemia. Firstly, the prevalence and extent of CAD, as well as procedural-related data was assessed comparing anemic and non-anemic patients. Secondly, the prognosis of anemic and non-anemic patients undergoing CA was investigated with regard to the primary endpoint in-hospital all-cause mortality at 30 days. Secondary endpoints comprised the risk of acute myocardial infarction (AMI), revascularization and hospitalization for heart failure at 36 months of follow-up. Statistical analyses included Kaplan-Meier analyses, as well as uni- and multivariable Cox proportional regression analyses.
Results: From 2016 to 2022, 7,645 patients undergoing CA were included with a mean and median hemoglobin level of 12.9 g/dL and 13.2 g/dl respectively. The corresponding prevalence of anemia was 38.5%. Anemic patients had a higher prevalence of CAD (76.3% vs 74.8%; p = 0.001) as well as a higher prevalence of 3-vessel CAD compared to non-anemic patients (36.1% vs. 24.9%; p = 0.001), alongside with higher rates of percutaneous coronary intervention (PCI) (45.3% - 41.5%; p = 0.001). At 30 days, the risk of in-hospital all-cause mortality was higher for anemic patients (12.6% vs. 2.5%; p = 0.001; HR = 3.173; 95% CI 2.564 – 3.926; p = 0.001), which was still evident after multivariable adjustment (HR = 1.719; 95% CI 1.001 – 2.954; p = 0.050). However, neither the risk of AMI at 36 months (8.4% vs. 7.4%, p=0.091), nor the risk of revascularization at 36 months (8.0% vs. 8.5%, p=0.447) was higher in anemic patients compared to non-anemic patients. Finally, the risk of rehospitalization for heart failure was increased in patients with anemia (27.4% vs. 18.4%; p = 0.001).
Conclusion: Anemia represents a common comorbidity affecting more than one third of patients undergoing CA and was independently associated with an increased risk of in-hospital all-cause mortality at 30 days.