Losartan May Not Prevent Vestibular Schwannoma Growth or Related Hearing Loss During Observation

Objective To evaluate the impact of losartan on vestibular schwannoma (VS) growth and related hearing loss during observation. Study design Retrospective cohort study Setting Tertiary referral center Patients Sporadic VS patients undergoing initial observation with at least two magnetic resonance imaging and audiologic examinations. Intervention Losartan Main Outcome Measures Endpoints included VS growth, quantitative audiologic changes, survival free of tumor growth, and survival free of nonserviceable hearing. Patient characteristics and endpoints were compared by losartan use. Results Seventy-nine patients were included, of which 33% were taking losartan. Tumor growth was observed in 50% of patients in the losartan group and 36% in the non-losartan group ( p = 0.329). Survival analysis failed to show a significant difference in the hazard rate of VS growth between groups (hazard ratio, 1.38; 95% confidence interval, 0.70–2.70; p = 0.346). Throughout observation, mean decreases in normalized pure-tone average were 5.5 and 9.3 dB in the losartan and non-losartan groups, respectively ( p = 0.908). Mean decreases in normalized word recognition score were 11.0 and 16.6% in the losartan and non-losartan groups, respectively ( p = 0.757). Nonserviceable hearing developed in 19% of patients in the losartan group and 28% in the non-losartan group ( p = 0.734). Survival analysis did not demonstrate a significant difference in the hazard rate of developing nonserviceable hearing between groups (hazard ratio, 1.71; 95% confidence interval, 0.56–5.21; p = 0.337). Conclusions Losartan use may not reduce the risk of VS growth or hearing loss during observation. A randomized trial would be ideal to further identify the true effect on growth and hearing.