Association between frailty and heart failure incident after acute coronary syndrome

Background Despite advances in treatment strategies that have substantially reduced mortality in patients with acute coronary syndrome (ACS), the incidence of heart failure (HF) after ACS remains high. Therefore, there is a need to identify risk factors for the development of HF in patients with ACS. Frailty, characterized by reduced physiological resilience and resistance to stressors, has been identified as a potential risk factor for the development of various diseases. Frailty in patients with ACS has received increasing attention and has been reported to be associated with poor prognosis and an increased risk of readmission. However, the association of frailty with the development of HF after ACS remains unclear. Purpose We aimed to clarify the association of frailty with the risk of developing HF in patients with ACS. Methods We included 877 patients with ACS who had no history of HF or complications of HF during hospitalization. Frailty was assessed using the Short Physical Performance Battery (SPPB), and the SPPB score ≤9 was defined as having frailty (1). Patients were categorized into two groups based on the presence or absence of frailty. The endpoint was the HF event. Kaplan-Meier curves and log-rank tests were conducted to compare the cumulative incidence of HF between the two groups. The relationship between frailty and subsequent HF risk was investigated using multivariate Cox regression analysis. As death can be a competing risk factor for HF events, we conducted a competing risk analysis. Results Overall, the median (interquartile range) age was 67 (57–74) years, 81.3% were men, and frailty was observed in 9.9%. During a mean follow-up of 4.2±3.5 years, 6.7% HF events were observed. The incidence of HF was 13.8 (95% confidence interval [CI]: 10.4–18.3) per 1,000 person-years in the non-frailty group and 56.4 (95% CI: 31.2–101.8) per 1,000 person-years in the frailty group. The cumulative incidence of HF events was significantly higher in the frailty group than in the non-frailty group (log-rank p <0.001; Figure 1). After multivariate adjustment, frailty was associated with a higher risk of HF (hazard ratio [HR]: 2.38, 95% CI: 1.16–4.87, p=0.018; Figure 1). Even if competing risks of death were considered, the results did not change (subHR: 2.16, 95% CI: 1.09–4.30). In subgroup analyses such as high B-type natriuretic peptide, multivessel disease, and diabetes mellitus, frailty was consistently associated with a higher risk of developing HF (Figure 2). When SPPB was treated as a continuous variable, the HR (95% CI) per 1-point decrease in SPPB for HF was 1.16 (1.05–1.29). Conclusions Frailty is associated with a higher risk of developing HF after ACS. The study suggests the importance of assessing not only basic attributes and cardiac and renal function but also the presence of frailty in order to assess the risk of developing HF after ACS. The relationship between frailty and HF. Subgroup analysis.