J Korean Med Assoc.  2023 Oct;66(10):573-580. 10.5124/jkma.2023.66.10.573.

Prognostic factors of sudden sensorineural hearing loss

• Kong TH

• KMID: 2547246
• DOI: http://doi.org/10.5124/jkma.2023.66.10.573

Abstract

Background
Sudden sensorineural hearing loss (SSNHL) refers to rapid and often unexplained decline in auditory acuity. Reported recovery rates for SSNHL vary across studies; however, these are usually within the range of 40% to 60%. Although numerous studies have investigated factors that affect auditory restoration, prediction of patients’ hearing recovery remains challenging.
Current Concepts
Natural recovery rates for SSNHL range between 32.0% and 65.0%, and treatments commonly include systemic steroid therapy and intratympanic dexamethasone injections. Adjunctive treatments, such as antiviral agents, vasodilators, anticoagulants, hyperbaric oxygen therapy, and stellate ganglion block therapy are also utilized. Recovery typically occurs within 2 weeks, and approximately 66.0% of patients have complete or partial hearing restoration. Recovery predominantly occurs early; approximately 78.2% to 90.0% patients recover within 1 month and >98.0% within 3 months. Age is an important factor associated with recovery; patients aged ≥40 years show low recovery rates. Coexisting dizziness is generally associated with unfavorable outcomes. Hearing loss severity and types (based on the frequency-specific pattern of hearing impairment) are associated with poor prognosis. Additionally, systemic conditions like hypertension and diabetes are implicated as etiopathogenetic contributors. In addition to a variety of audiological assessments to evaluate cochlear function, environmental factors, including particulate matter and air pollution affect outcomes.
Discussion and Conclusion
During SSNHL treatment, evaluation of factors known to affect recovery is important to determine patients’ hearing restoration potential. Proactive patient counseling is necessary to guide treatment decision-making, particularly for initiation of auditory rehabilitation following incomplete or lack of recovery. Significant variables that affect hearing recovery are useful prognostic indicators. These studies are expected to provide better understanding of the pathophysiology of SSNHL and offer an evidence-based foundation for therapeutic interventions.

Keyword

Sensorineural hearing loss; Sudden hearing loss; Pathophysiology; Prognosis; 감각신경난청; 돌발난청; 병태생리; 예후