Auditory Prognosis of Patients With Sudden Sensorineural Hearing Loss in Relation to the Presence of Acute Vestibular Syndrome: A Systematic Literature Review and Meta-Analysis

Objectives: Hearing recovery following idiopathic sudden sensorineural hearing loss (ISSNHL) is influenced by various prognostic factors, and the presence of acute vestibular syndrome (AVS) may adversely impact auditory outcomes. Evaluating vestibular function in SSNHL patients could offer insights into predicting hearing recovery. This systematic review aims to assess whether the presence of AVS exacerbates the audiological prognosis of ISSNHL. Design: A comprehensive systematic review was conducted using databases such as PubMed, Cochrane Library, EMBASE, and Scopus, encompassing articles published in the last decade. Included were retrospective and prospective case-control and cohort studies, as well as randomized clinical trials. Meta-analysis was performed based on the findings from these studies. Results: Among 386 articles identified, six addressed the systematic review’s question, all being retrospective studies. These articles collectively involved 393 patients for the meta-analysis. Vestibular function assessment methods varied widely, posing challenges for direct comparisons. The likelihood of unfavorable hearing outcomes was 2.29 times higher in patients with associated AVS. Hearing recovery was 3.22 times more likely to be worse in patients with altered cervical vestibular evoked myogenic potentials-air-conducted sound. Abnormal caloric test results showed no significant association with worse hearing prognosis, although patients with unaltered caloric tests demonstrated a significantly greater improvement in pure-tone audiometry. Conclusions: Hearing recovery from ISSNHL appears to be diminished in patients with associated AVS and abnormal vestibular test results.