Comparison of the prognostic value of frailty assessment tools in patients aged ≥ 65 years hospitalized in a cardiac care unit with acute coronary syndrome

BACKGROUND: Frailty is associated with adverse events in elderly patients with acute coronary syndrome (ACS). Our aim was to compare the prognostic value of four frailty scales in patients aged ≥ 65 years hospitalized with ACS in a cardiac care unit (CCU). METHODS: Patients aged ≥ 65 years with ACS were included. Frailty was assessed using the Fried frailty scale (reference standard), the Edmonton Frail Scale (EFS), the FRAIL scale, and the Clinical frailty scale (CFS). The primary end point was all-cause mortality and the secondary end point was unscheduled rehospitalization. RESULTS: One hundred and seventy four patients aged ≥ 65 years with ACS were recruited. The median follow-up was 637.5 days. Frailty was identified in 41.4%, 40.2%, 39.1% and 36.3% patients by the Fried frailty scale, EFS, FRAIL scale and CFS, respectively. The agreement coefficients were 0.88, 0.86, and 0.79 for the FRAIL scale, EFS and CFS, respectively. In the Cox regression model, frailty was associated with all-cause mortality regardless of the scale used (univariate: hazard ratio [HR] 95% CI = 10.5, 2.4–46.8 Fried frailty scale; 12.0, 2.7–53.4 FRAIL scale; 7.1, 2.0–25.2 EFS; 8.3, 2.4–29.6 CFS. Multivariate: HR = 5.1, 1.1–23.8 Fried frailty scale; 5.7, 1.2–26.8 FRAIL scale; 3.7, 1.0–14.0 EFS; 4.2, 1.1–15.9 CFS). The FRAIL scale had the highest HR. In the univariate analysis, frailty was associated with unscheduled rehospitalization (HR = 3.2, 1.7–6.0 Fried frailty scale; 3.4, 1.8–6.3 FRAIL scale; 3.5, 1.8–6.6 EFS; 3.1, 1.7–5.8 CFS). In the multivariate analysis, only the EFS independently predicted unscheduled rehospitalization (HR = 2.2, 1.1–4.63). CONCLUSIONS: Frailty assessed by the Fried frailty scale, FRAIL scale, EFS and CFS is associated with all-cause mortality and unscheduled rehospitalization in elderly patients hospitalized in a CCU with ACS. The adjusted HR of the FRAIL scale for all-cause mortality was the highest among the scales compared, whereas the EFS was an independent predictor of unscheduled rehospitalization. These data should be taken into consideration when choosing a frailty assessment tool.