Sensorineural Hearing Loss Associated with Neomycin Eardrops and Nonintact Tympanic Membranes

Abstract

Objective Use of neomycin eardrops in nonintact tympanic membranes (NITMs) due to tympanic membrane (TM) perforation or tympanostomy tubes (TTs) is controversial because of the potential for ototoxicity. We sought to compare the risk of sensorineural hearing loss (SNHL) in patients with NITMs who received neomycin with those who received fluoroquinolone eardrops. Study Design Retrospective cohort study. Setting Administrative claims data analysis, including diagnoses and procedure detail for physician office and hospital visits and pharmacy dispensing events in children eligible for Medicaid fee-for-service benefits in 29 states between 1999 and 2006. Subjects and Methods Eligible patients (age <18 years) had to have received a study eardrop within 12 months after first diagnosis of NITM. The follow-up period started from the first eardrop dispensing. Main Outcome Measures We compared the 12-month risk of SNHL using Cox proportional hazards regression models adjusted for SNHL risk factors. Results We found 982 SNHL cases in 134,598 children treated with neomycin or fluoroquinolone eardrops. The adjusted hazard ratio (HR) for 1, 2, and 3 or more prescriptions of neomycin was 0.90 (95% confidence interval [CI], 0.76-1.07), 1.45 (1.05-2.01), and 1.30 (0.71-2.36), respectively, when adjusted for SNHL risk factors, the interval between initial diagnosis of NITM and eardrop initiation, and total number of eardrop prescriptions. The results remained unchanged for several sensitivity analyses. Conclusion Short-term use of neomycin eardrops in patients with NITMs is not associated with an increased risk of SNHL; however, repeated doses (ie, ≥2 prescriptions) showed a significant association with an increased risk of SNHL.