The 5-Item Modified Frailty Index Predicts Postoperative Complications After Cochlear Implantation

Objective: Examine the relationship between frailty and postoperative outcomes in cochlear implant (CI) recipients. Study design: Retrospective cohort study. Setting: Epic Cosmos Database. Subject population: A total of 23,550 cochlear implantations between 2015 and 2023. Intervention: Unilateral or bilateral cochlear implantation. Main outcome measures: Rates of CI explantation, inpatient admission, nonhome discharge, and major complications such as stroke, myocardial infarction, and renal failure. Results: Of 23,550 cochlear implantations identified, 53.1% were male, and the average age at implantation was 64.1 years (SD 17.3). The average mFI-5 score was 0.66 (SD 0.81), with 53% of patients having an mFI-5 score of 0. Fewer than 1% of cases had postoperative explantation, inpatient admission, or major complications. Frailty, as measured by mFI-5, was a strong predictor for rates of postoperative complications, readmission, and nonhome discharge. For each one-point increase in mFI-5 score, the odds ratio increased by 1.84 for postoperative inpatient admission ( P <0.000001, 95% CI: 1.70-1.98), 1.41 for discharge to nonhome locations ( P <0.001, 95% CI: 1.18-1.67), and 2.15 for major complications ( P <0.000001, 95% CI: 1.95-2.38). This was as high as 6.96, 2.26, and 8.27, respectively, for severely frail patients (mFI-5 ≥ 3). Age was not a strong predictor of any of the outcome measures. Explanation rates were not significantly associated with frailty scores or age. Conclusion: CI remains a generally safe procedure with low overall complication rates. Contrary to prior studies, frailty as measured by the mFI-5 is a strong predictor of postoperative complications and adverse events for patients undergoing CI.