Modified frailty index as an indicator for outcomes, discharge status, and readmission after lower extremity bypass surgery for critical limb ischemia.

Frailty has been associated with poor postoperative outcomes. This study evaluated the 5-factor modified frailty index (mFI-5) to assess complications, mortality, discharge disposition, and readmission in patients undergoing lower extremity (LE) bypass for critical limb ischemia (CLI).The National Surgical Quality Improvement Program vascular module (2011-2017) was utilized to identify patients undergoing LE bypass for CLI. Adverse events included infectious complications, bleeding complications, prolonged ventilation, amputation, readmission, and death. Patients were divided into groups based on mFI-5 scores: mFI1 (0), mFI2 (0.2), mFI3 (0.4), and mFI4 (0.6-1). Data were analyzed using the Cochran-Mantel-Haenszel statistic for general association and multivariable logistic regression. About 11,530 patients undergoing bypass for CLI were identified (42% rest pain and 58% tissue loss; 23% mFI1, 31% mFI2, 27% mFI3, and 19% mFI4; 64% men and 36% women). An increase in mFI-5 was associated with higher 30-day mortality (mFI1 = 0.62%; mFI12 = 1.45%; mFI13 = 1.35%; and mFI14 = 3.09%; P < .0001). After adjustment for age, mFI4 was associated with increased mortality compared with mFI1 (odds ratio, 3.80; 95% confidence interval, 1.69-8.54). Increased mFI-5 was associated with bleeding complications, wound infections, urinary tract infections, prolonged ventilation, sepsis, unplanned reoperations, and discharge to nonhome destination (all P < .01). Compared with mFI1 (13.5%), mFI4 was associated with increased 30-day readmission (24.8%, P < .0001). In patients undergoing LE bypass for CLI, higher mFI-5 was associated with increased postoperative complications, in-hospital and 30-day mortality, nonhome discharge, and 30-day readmission. The mFI-5 as an easily calculated tool can identify patients at high risk for inferior outcomes. It should be incorporated into discharge planning after LE bypass for CLI.