Analysis of the causes of death in elderly patients with acute decompensated heart failure aged 75 years and over

Abstract

Objective To explore the clinical characteristics and causes of death in patients with acute heart failure at aged 75 and over. Methods The prospective study collected 175 patients with acute heart failure from January 2012 to December 2014.They were divided into ≥75 years old group and<75 years old group and the general clinical data were recorded.Follow-up was performed mainly by telephone with supplemented hospitalization follow-up and outpatient follow-up.Survival rates were assessed by Kaplan-Meier method.The survival rate difference between the two groups was compared using the log-rank test.Multivariate Cox proportional hazards regression analysis was used to determine the independent risk factors for death. Results The proportions of ischemic heart disease, hypertension and old myocardial infarction were higher in the elderly group than in the young group with a higher proportion of male, diabetes and body mass index in <75 years old group.Elderly group had a higher level of left ventricular ejection fraction(LVEF)and a lower level of total cholesterol, triglycerides and low density lipoprotein cholesterol(LDL-C). Kaplan-Meier curves showed that all-cause mortality(χ2=4.005, P=0.045)and non-cardiovascular mortality(χ2=4.418, P=0.041)were significantly higher in the elderly group than in the younger group, whereas cardiovascular mortality had no significant difference between the two groups(χ2=0.754, P=0.385). In patients with non-cardiovascular mortality, 12 cases(63.2%)died of pulmonary infection in elderly group, 3 cases(25.0%)died of lung infection in younger group, and the difference was statistically significant between the 2 groups(χ2=4.288, P=0.038). Multivariate Cox proportional hazards regression analysis showed that age≥75 years was an independent predictor for both non-cardiovascular mortality[HR(95%CI): 2.71(1.50-6.55), Wald χ2=2.266, P=0.038]and all-cause mortality[HR(95%CI): 1.75(1.28-3.13), Wald χ2=2.914, P=0.026]in patients with acute heart failure. Conclusions Age ≥75 years is an independent risk factor for all dead patients with acute heart failure and non-cardiovascular death, but it is not the independent risk factors for cardiovascular death, which is of great significance to establish a more rational treatment strategy for senile heart failure. Key words: Acute decompensated heart failure; Risk factors; Prognosis