Introduction: Little is known about the prevalence and prognostic impact of patient (pt) frailty on in-hospital mortality in the setting of acute MI, or the optimal way to assess frailty in this setting.
Methods: We examined the relationship between frailty and outcomes in acute MI pts ≥65 years from January 1, 2015 to December 31, 2016 in ACTION Registry-GWTG. Three spheres of pre-hospital function (cognition, ambulation, and functional independence) were assessed, and findings were summed in two new ways: (1) ACTION Frailty Scale based on responses to six groups adapted from the Canadian Study of Health and Aging Clinical Frailty Scale; (2) ACTION Frailty Score derived by summing a rank score of 0-2 assigned for each grade (range 0-6). Associations between frailty status and all-cause mortality were estimated using multivariable logistic regression.
Results: Among 143,722 acute MI pts at 778 hospitals, 108,059 (75.2%) were fit/well and 6,484 (4.5%) were vulnerable to frailty, while 7,527 (5.2%) had mild, 3,913 (2.7%) moderate, 2,715 (1.9%) severe, and 632 (0.4%) very severe frailty according to the ACTION Frailty Scale; 14,392 (10.0%) could not be categorized. Increasing severity of frailty by this scale was associated with step-wise higher risk for in-hospital mortality (P-trend <0.001; Table). Patient categories of the ACTION Frailty Score provided similar results. After adjustment for clinical risk predictors, each 1-unit increase in frailty score was associated with a 12% higher mortality risk (OR 1.12, 95% CI 1.10-1.15), a risk that emerged even among mildly frail pts (OR 1.35, 95% CI 1.22-1.49).
Conclusions: Increasing severity of frailty is associated with in-hospital mortality risk in the setting of acute MI using two assessment methods. Risk-benefit calculations that underlie major treatment decisions in MI patients may be better informed by incorporating an objective measure of frailty to ensure clinical decision-making matches long-term goals of care.