Cluster approach to identifying the 5-year prognosis of patients with chronic heart failure of ischemic etiology

BACKGROUND: The phenotypic and pathophysiological heterogeneity of patients with chronic heart failure increases the interest of researchers in grouping according to similar clinical and genetic characteristics based on cluster analysis. AIM: To identify phenotypic subgroups in a multivariate cohort of patients with chronic heart failure secondary to coronary artery disease using uncontrolled cluster analysis of clinical, instrumental and genetic components. MATERIAL AND METHODS: 470 patients with chronic heart failure of functional class I–IV, stable course, ischemic etiology of both sexes at the age of 66.4±10.4 years were examined. A clinical study was conducted, genotyping single nucleotide polymorphisms rs10927875 of the ZBTB17 gene, rs247616 of the CETP gene, rs1143634 of the IL-1β gene, rs1800629 of the TNF gene, rs1800795 of the IL-6 gene was carried out, and patient outcomes were assessed for 5 years. Quantitative data were presented as mean and standard deviation or median and interquartile range; categorical — as frequencies and percentages. Categorical intergroup differences were tested using the χ2 test, and quantitative differences were tested using the Student/Mann–Whitney test. Hierarchical clustering was carried out according to 44 demographic, clinical, genetic variables, time to event was analyzed by the Kaplan–Meier method, risk ratio — by Cox regression. Statistical processing was carried out in the R4.3.1 program. RESULTS: Two clusters of patients with heart failure were identified. Cluster 1 (66%) included older patients of both sexes, predominantly functional class III–IV chronic heart failure, with enlarged heart chambers, reduced left ventricular ejection fraction, higher heart rate, atrial fibrillation and left ventricular hypertrophy. In this cluster, more carriers of the GG genotype of the rs1800795 polymorphism of the IL-6 gene (p 0.001) and the CT genotype of the rs247616 polymorphism of the CETP gene (p=0.014) were identified. Cluster 2 (34%) was represented predominantly by younger women, with a higher metabolic index, a history of myocardial infarction and coronary intervention, smokers, and a larger proportion of the TT genotype of the rs247616 polymorphism of the CETP gene (p=0.029). CONCLUSION: 2 clusters of patients with chronic heart failure, characterized by a different set of 44 variables that determine the risk of death from all causes, were identified.