The Fried Frailty Phenotype in Patients Undergoing Cardiac Surgery: A Systematic Review and Meta-Analysis

Objective: Frailty is an increasingly recognized marker of poor surgical outcomes in cardiac surgery. Frailty first was described in the seminal “Fried” paper, which constitutes the longest-standing and most well-recognized definition. This study aimed to assess the impact of the Fried and modified Fried frailty classifications on patient outcomes following cardiac surgery. Methods: The PUBMED, MEDLINE, and EMBASE databases were searched from January 2000 until August 2021 for studies evaluating postoperative outcomes using the Fried or modified Fried frailty indexes in open cardiac surgical procedures. Primary outcomes were one-year survival and postoperative quality of life. Secondary outcomes included postoperative complications, intensive care unit (ICU) length of stay (LOS), total hospital LOS, and institutional discharge. Results: Eight eligible studies were identified. Meta-analysis identified that frailty was associated with an increased risk of one-year mortality (Risk Ratio [RR]:2.23;95% confidence interval [CI]1.17 -4.23), postoperative complications (RR 1.78;95% CI 1.27 – 2.50), ICU LOS (Mean difference [MD] 21.2 hours;95% CI 8.42 – 33.94), hospital LOS (MD 3.29 days; 95% CI 2.19 – 4.94), and institutional discharge (RR 3.29;95% CI 2.19 – 4.94). A narrative review of quality of life suggested an improvement following surgery, with frail patients demonstrating a greater improvement from baseline over non-frail patients. Conclusions: Frailty is associated with a higher degree of surgical morbidity, and frail patients are twice as likely to experience mortality within one-year post-operatively. Despite this, quality of life also improves dramatically in frail patients. Frailty, in itself, does not constitute a contraindication to cardiac surgery.