How Do Patient Comorbidities Impact Adult Cochlear Implant Outcomes?

Introduction: Cochlear implant (CI) recipients display variability in early and long-term speech recognition (SR) and patient-reported outcome measures (PROMs). Medical comorbidities influence outcomes for many chronic conditions including diabetes, cancer, and cardiovascular disease. Our objective was to evaluate the relationship between preoperative comorbidities and post-CI SR and PROMs.

Methods: Adults with bilateral hearing loss who received CIs from 2017 to 2022 were included. Thirty-two comorbidities were determined via an in-depth chart review analyzing anesthesia preoperative notes, medication lists, and encounter notes with other caretakers. Three comorbidity scores were computed: Charlson Index (10-year mortality), Elixhauser Index (30-day mortality), and a basic sum score (equal weight to each comorbidity). Associations between comorbidity scores and early (1-, and 3-months) and late post-CI (6- and 12-months) outcomes were analyzed using Spearman rho correlations. Clinical SR measures included word recognition (CNC), sentence recognition in quiet (AzBioQ), and noise (AzBioN) in best-aided condition, and PROMs included Speech, Spatial and Qualities of Hearing Scale (SSQ-12) and Cochlear Implant Quality of Life (CIQOL-10).

Results: A total of 343 patients met inclusion criteria. Charlson Index scores were significantly related to early and late post-CI SR, including CNC, AzBio, and AzBioN (rs = -.18 – -.29). Elixhauser Index scores were significantly related to early post-CI SR for CNC and AzBioQ (rs = -.13 and -.18, respectively). The basic sum score showed a significant association with late AzBioQ (rs = -.22). There were no significant relationships between comorbidity scores and PROMs.

Conclusions: Comorbidity scores were significantly associated with early and late CI SR outcomes. The stronger association with the Charlson Index, which predicts 10-year mortality, suggests overlap between factors influencing long-term survival and CI success. Evaluating comorbidities may help optimize CI outcomes through improved preoperative counseling and planning.