Impact of the clinical frailty scale on mid-term mortality in patients with ST-elevated myocardial infarction

BACKGROUND: "Frailty" is associated with poor prognosis in ST-elevated myocardial infarction (STEMI). However, there is little data regarding the impact of the Canadian Study of Health and Aging Clinical Frailty Scale (CFS), a simple and semiquantitative tool for assessing frailty, on mid-term mortality in STEMI patients. METHODS: A total of 354 consecutive STEMI patients (mean age 69.8 ± 12.4 years; male 76.6%) who underwent percutaneous intervention between July 2014 and March 2017 were retrospectively reviewed. The study endpoint was mid-term mortality according to the CFS classification. Furthermore, in order to clarify the impact of CFS upon admission on mid-term mortality, the independent predictors of all-cause death were evaluated. RESULTS: Patients were categorized into three groups (CFS 1-3, n = 281; CFS 4-5, n = 62; and CFS 6-7, n = 11). During the study period (median 474 days), all-cause death was observed in 39 patients. After multivariate Cox regression analysis, higher CFS (adjusted hazard ratio HR 2.34, 95% confidence interval CI 1.43-3.85, p < 0.001), higher Killip score (adjusted HR 2.46, 95%CI 1.30-5.78, p = 0.002), and lower serum albumin level (adjusted HR 4.29, 95%CI 2.16-8.51, p < 0.001) were significantly associated with an increased risk of all-cause death. CONCLUSION: In conclusion, severe frailty was associated with mid-term mortality in STEMI patients who underwent PCI.