Correlation between audiovestibular function tests and hearing outcomes in severe to profound sudden sensorineural hearing loss.

ABSTRACT

OBJECTIVE: This study investigated whether audiovestibular function tests, namely auditory brain stem response (ABR) and vestibular-evoked myogenic potential (VEMP) tests were correlated to hearing outcomes after controlling the effects of other potential confounding factors in severe to profound sudden sensorineural hearing loss (SSHL). DESIGN: Eighty-eight patients with severe to profound SSHL were enrolled in this study. Pretreatment hearing levels, results of audiovestibular function tests, and final hearing outcomes were recorded from retrospective chart reviews. Other factors, including age, gender, delay of treatment, vertigo, diabetes mellitus, and hypertension, were collected as well. Comparative analysis between multiple variables and hearing outcomes was conducted using the cumulative logits model in overall subjects. Further, multivariate analysis of prognostic factors was conducted in the stratified groups of severe (70 dB HL <hearing level < or =90 dB HL) and profound (hearing level >90 dB HL) SSHL. RESULTS: Multivariate analysis showed that pretreatment hearing levels, presence of vertigo, and results of ABR and VEMP testing were significant outcome predictors in the overall subjects. Stratification analysis demonstrated that both the presence of ABR and VEMP waveforms were significantly correlated with better hearing outcomes in the group of severe SSHL [ABR adjusted odds ratio (aOR) = 14.7, 95% confidence interval (CI) = 1.78 to 122, p = 0.01; VEMP aOR = 5.91, 95% CI = 1.18 to 29.5, p = 0.03], whereas the presence of vertigo was the only significant negative prognostic factor in the group of profound SSHL (aOR = 0.24, 95% CI = 0.06 to 0.95, p = 0.04). Other variables, including age, gender, diabetes mellitus, hypertension, and delay of treatment, were not significantly related to hearing outcomes in both groups (p > 0.05). A predictive hearing recovery table with the combined ABR and VEMP results was proposed for the group of severe SSHL. CONCLUSIONS: ABR and VEMP tests should be included in the battery of neurootological examinations in patients with severe SSHL because the presence of both waveforms might indicate favorable hearing outcomes. The presence of vertigo might portend a worse prognosis in patients with profound SSHL. A presumed table in predicting hearing outcomes was suggested for patients with severe SSHL.