Conductive Hearing Loss Associates With Dementia, and Middle Ear Reconstruction Mitigates This Association: A Multinational Database Study

Objective To test the hypothesis that conductive hearing loss (CHL) is associated with dementia, and that middle ear reconstruction (MER) associates with improved outcomes for these measures in a multinational electronic health records database. Study Design Retrospective cohort study with propensity-score matching (PSM). Setting TriNetX is a research database representing about 110 million patients from the United States, Taiwan, Brazil, and India. Patients Subjects older than 50 years with no HL and any CHL (ICD-10: H90.0–2). Subjects of any age with and without any MER (CPT: 1010174). Main Outcome Measures Odds ratios (ORs) and hazard ratios with 95% confidence intervals (95% CIs) for incident dementia (ICD-10: F01, F03, G30). Results Of 103,609 patients older than 50 years experiencing any CHL, 2.74% developed dementia compared with 1.22% of 38,216,019 patients with no HL (OR, 95% CI: 2.29, 2.20–2.37). Of patients experiencing CHL, there were 39,850 who received MER. The average age was 31.3 years, with 51% female patients. A total of 343,876 control patients with CHL were identified; 39,900 patients remained in each cohort after 1:1 PSM for HL- and dementia-related risk factors. Matched risk for developing dementia among MER recipients was 0.33% compared with 0.58% in controls (OR: 0.58, 0.46–0.72). Conclusions CHL increases the odds for dementia, and MER improves the odds for incident dementia. This study represents the first population study on the topic of CHL, MER, and dementia.