Severe sudden sensorineural hearing loss related to risk of stroke and atherosclerosis

Nobuyoshi Tsuzuki,Takanori Nishiyama,Koichiro Wasano,Marie Shimanuki,Seiichi Shinden,Ko Hentona,Naoki Oishi,Kaoru Ogawa,Yoshihiko Hiraga

doi:10.1038/s41598-021-99731-w

Abstract

The cause of idiopathic sudden sensorineural hearing loss (idiopathic SSNHL)—diagnosed after excluding other causes of hearing loss, such as SSNHL associated with vestibular schwannoma (VS)—is unknown. The presumed pathogenesis of idiopathic SSNHL includes circulatory disorders (e.g., cochlear infarction). We tested the hypothesis that patients with SSNHL who are at high stroke risk will have a lower rate of VS compared to those with low stroke risk. The rationale is that the primary cause of SSNHL in patients with high stroke risk might be a circulatory disturbance. We conducted a retrospective study in six hospitals. Our sampling of SSNHL patients included those diagnosed with idiopathic SSNHL and VS-associated SSNHL. SSNHL patients who had a head MRI were stratified by severity of hearing loss and evaluated for differences in the detection rate of VS between the high-scoring CHADS2 (CHADS2-H-), an index of stroke risk, and low-scoring CHADS2 (CHADS2-L-) groups. We identified 916 patients who met the inclusion criteria. For severe hearing loss, the CHADS2-H group had a significantly lower rate of VS than the CHADS2-L group (OR 0 [95% CI 0.00–0.612]; P = 0.007). These results indirectly support the hypothesis that a primary cause of severe idiopathic SSNHL in those at high risk of stroke might be a circulatory disorder.

Highlights

Main symptoms Sudden onset Severe sensorineural hearing loss Unknown etiology For reference Hearing loss Exclude cases diagnosed as acute low-tone sensorineural hearing loss Exclude functional hearing loss Sudden onset of hearing loss; may progressively deteriorate over a few days No repeated episodes of improvement or worsening of hearing loss Unilateral hearing loss, but may be bilateral at the onset May be accompanied by tinnitus around the time of onset of hearing loss May be accompanied by vertigo, nausea, and/or vomiting around the time of onset of hearing loss, without recurrent episodes of vertigo No cranial nerve symptoms other than from cranial nerve VIII Definite diagnosis: All of the above main symptoms are present
Using receiver operating characteristic (ROC) curve analysis, we determined that the optimal cutoff values for the CHADS2 score were at two points (CHADS2-H, CHADS2-L) on the specificity-sensitivity curve
We found no significant difference in the rate of CHADS2-H and CHADS2-L between SSNHL patients with vestibular schwannoma (VS) and those without VS (p = 0.06) (odds ratio (OR), 0.38 [95% CI 0.099–1.066])

Summary

Introduction

Main symptoms Sudden onset Severe sensorineural hearing loss Unknown etiology For reference Hearing loss (i.e., hearing loss of 30 dB or more over three consecutive frequencies within 72 h) Exclude cases diagnosed as acute low-tone sensorineural hearing loss Exclude functional hearing loss Sudden onset of hearing loss; may progressively deteriorate over a few days No repeated episodes of improvement or worsening of hearing loss Unilateral hearing loss, but may be bilateral at the onset May be accompanied by tinnitus around the time of onset of hearing loss May be accompanied by vertigo, nausea, and/or vomiting around the time of onset of hearing loss, without recurrent episodes of vertigo No cranial nerve symptoms other than from cranial nerve VIII Definite diagnosis: All of the above main symptoms are present. The CHADS2 score is one method for assessing stroke and atherosclerosis risk in patients with non-rheumatic atrial fibrillation. CHADS2 is essentially a set of clinical prediction rules for estimating risk. The CHADS2 score may be useful as a predictor of cardiovascular/cerebrovascular events in patients with coronary artery disease lacking atrial fibrillation and as a prognosticator for patients with acute myocardial infarction[12,13]. The present study tested this hypothesis by comparing the rate of VS in patients with SSNHL, who were stratified by CHADS2 score and severity of hearing loss. We estimated the population of idiopathic SSNHL patients who are at risk for stroke and atherosclerosis by using CHADS2 scores and severity of hearing loss

Objectives

Methods

Results

Conclusion