Frailty Screening Tool for Patients Undergoing Orthotopic Heart Transplant

Background: Although frailty has been previously shown to negatively influence postoperative outcomes, frailty measurements remain undefined and underused for patients undergoing orthotopic heart transplantation (OHT). This study aims to derive and validate an OHT frailty screening tool.

Methods: The United Network for Organ Sharing database was queried for adults undergoing OHT between 2000 and 2018. The total population was randomly divided into derivation (80%) and validation (20%) cohorts. The primary outcome was mortality. Secondary outcomes included rates of major morbidities and hospital length of stay. Variables that were constructs within preexisting frailty tools and that were predictive of a composite frailty outcome within the derivation cohort were incorporated into a multivariable regression model (exploratory, P < .2). Independent predictors of frailty were included in the OHT frailty screening tool.

Results: A total of 36,790 OHT recipients met the criteria for inclusion. Twelve variables were identified as independent predictors of frailty and included as OHT frailty screening tool constructs. Recipients in the validation cohort were stratified as nonfrail (72.9%, n = 5363), prefrail (24.4%, n = 1795), and frail (2.7%, n = 200). Frail patients had significantly higher rates of posttransplant stroke, renal failure, and mortality at all time intervals as well as longer length of stay (all P < .001). The risk model's predictive rates of mortality strongly correlated with the observed rates of mortality (r² = 0.97, P < .001). The c-index of the OHT frailty score was 0.74.

Conclusions: The OHT frailty screening tool is highly predictive of adverse posttransplant outcomes. This screening tool may provide a framework to enhance existing risk stratification tools and improve overall resource utilization.