Predictors of Poor Hearing Outcomes Following Primary Stapes Surgery: A Study From the Swedish Quality Register for Otosclerosis Surgery

OBJECTIVE: To identify preoperative and perioperative factors associated with unchanged or worsened hearing after primary stapes surgery for otosclerosis. STUDY DESIGN: Registry-based study. SETTING: Nationwide Swedish Quality Register for Otosclerosis Surgery including procedures performed at county and university hospitals. PATIENTS: A total of 1813 adult patients underwent primary stapes surgery between 2009 and 2020 with complete preoperative and 1-year postoperative audiometry. INTERVENTION: Primary stapes surgery. MAIN OUTCOME MEASURES: Unchanged or worsened hearing one year postoperatively defined as one or more of the following: air conduction (AC) threshold improvement ≤5 dB [pure tone average for 0.5, 1, 2, and 4 kHz (PTA4)]; bone conduction deterioration ≥10 dB (PTA4); increased air-bone gap (ABG) ≥0 dB (PTA4); or worsening of high-frequency thresholds (PTA 4, 6, 8 kHz) ≥15 dB. RESULTS: Unchanged or worsened hearing occurred in 7% of cases. Multivariate logistic regression identified smaller preoperative ABG [≤23.8 dB; odds ratio (OR)=2.3, P <0.001], lower AC thresholds (≤45.0 dB HL; OR=2.1, P=0.002), older age (55 to 64 y: OR=2.1, P=0.007; ≥65 y: OR=2.3, P=0.012), and stapedectomy (compared with stapedotomy) (OR 3.5, P=0.025) as predictors of unchanged or worsened hearing. CONCLUSIONS: Smaller preoperative ABG, better baseline AC thresholds, and older age emerged as key predictors of unchanged or worsened hearing. These findings highlight the importance of careful patient selection and counseling, particularly for individuals with mild conductive hearing loss or of advanced age.