Incidence and predictors of significant hearing loss requiring hearing assistive devices among childhood cancer survivors: A population-based study.

Abstract

10055 Background: Though hearing loss is a significant late effect among childhood cancer survivors, recent guidelines note insufficient evidence to quantify natural history or risk associated with specific exposures. We examined the long-term incidence and predictors of hearing loss requiring hearing amplification devices (HAD) using population-based healthcare data. Methods: In Ontario, Canada, HAD costs are subsidized by the provincial Assistive Devices Program (ADP). Ontario children age <18 years at cancer diagnosis between 1987-2016 were identified using a pediatric cancer registry and linked to ADP claims. The cumulative incidence of HAD use was compared between cases and matched controls. Patient, disease, and treatment predictors of HAD were examined. Results: We identified 11,842 cases and 59,210 matched controls. Cases were at higher risk of HAD [hazard ratio (HR) 12.8, 95% confidence interval (95CI) 9.8-16.7; p<0.001]. The cumulative incidence of HAD among survivors was 2.1% (95CI 1.7-2.5%) at 20-years and 6.4% (95CI 2.8-12.1%) at 30-years. 30-year incidence was highest in survivors of neuroblastoma (10.7%, 95CI 3.8-21.7%) and hepatoblastoma (16.2%, 95CI 8.6-26.0%). Predictors of HAD in multivariable analyses included age 0-4 years at diagnosis (vs. 5-9 years, HR 2.2, 95CI 1.4-3.3; p<0.001). Relative to no cisplatin exposure, patients receiving 1-200mg/m2 were not at greater risk, unlike those receiving higher cumulative doses (Table). Relative to no radiation, those receiving ≤32Gy were at no higher risk, unlike while those receiving >32Gy. Carboplatin exposure was not associated with HAD. Conclusions: Childhood cancer survivors are at elevated risk of requiring HAD which continues to rise between 20 and 30 years from diagnosis. Thresholds of cisplatin and radiation exposure exist above which risk substantially increases. Prolonged monitoring and trials of otoprotective agents are warranted in high-risk populations. [Table: see text]