Frailty and Age as Predictors of Mortality in Acute Myocardial Infarction Complicated by Cardiogenic Shock

Cardiogenic shock is a serious complication of acute myocardial infarction (AMICS) with an in-hospital mortality rate of approximately 50%. Frailty is associated with poor outcomes in general but has been poorly investigated in AMICS. The purpose of this study was to evaluate the independent and combined effects of frailty and age on mortality in AMICS patients. We conducted a retrospective observational study using the RETROSHOCK cohort, including 1,716 AMICS patients admitted to 2 tertiary university hospitals in Denmark (2010-2017). Frailty was assessed using the Hospital Frailty Risk Score, with frailty defined as a score ≥5. Patients were further stratified by age ≥70 and <70 years old. In a separate analysis, age was categorized into 5 groups at 10-year intervals. Mortality was assessed at 30 days, 1 year (30-day landmark), and 10 years (30-day landmark). Frailty was present in 22% (n = 381). The median age was 69.5 years (IQR: 61-77). The 30-day mortality rate was 65% in frail patients compared to 51% in nonfrail patients, P < 0.001. The highest mortality was observed in patients aged ≥80 years (82%; P < 0.001) at 30 days, with more than 9-fold adjusted increased risk of death compared to nonfrail patients under 50 years (adjusted HR: 9.18; 95% CI: 4.66-18.1; P < 0.001). Combined analysis of age and frailty demonstrated 73% mortality in frail patients ≥70 years at 30 days and 82% at 10 years (30-day landmark). Frailty remained independently associated with increased risk of mortality (aHR: 1.84; 95% CI: 1.37-2.46; P < 0.001). Frailty and age are strong, independent predictors of mortality in AMICS.