Sensorineural hearing loss in type 2 diabetes mellitus patients: a systematic review of treatments and outcomes

INTRODUCTION: Sudden sensorineural hearing loss (SSNHL) in type 2 diabetes mellitus (T2DM) patients represents a complex therapeutic challenge that requires balancing audiological outcomes and metabolic safety. Current treatment guidelines do not provide specific recommendations for diabetic patients, despite evidence suggesting altered treatment responses and increased complication risks in this population. EVIDENCE ACQUISITION: A systematic review was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Electronic search was performed in MEDLINE, Embase, Web of Science, Cochrane Library, Scopus, and ClinicalTrials.gov databases using terms related to SSNHL and diabetes mellitus. Only prospective studies reporting treatment outcomes for SSNHL in diabetic patients were included. Primary outcomes included audiological improvement, while secondary outcomes encompassed metabolic adverse events and treatment safety. EVIDENCE SYNTHESIS: Five studies published between 2006 and 2024 were included, involving 322 diabetic patients with SSNHL. Treatment modalities included intratympanic corticosteroids (ITCS), oral corticosteroids (OCS), intravenous corticosteroids (IVCS), hyperbaric oxygen therapy (HBOT), prostaglandin E, and doluperine (DOLU). ITCS combined with DOLU achieved the highest reported success rate (86.7%), followed by HBOT combined with medications (84.0%) and ITCS alone (79.4%). Metabolic adverse events were rare, occurring in 2.7% of patients receiving systemic corticosteroids, while no hyperglycemic episodes were reported with ITCS therapy. Baseline glycemic control was generally suboptimal across studies (HbA1c 7.6-8.3%). CONCLUSIONS: Multiple treatment modalities demonstrate efficacy for SSNHL in diabetic patients, with intratympanic approaches offering superior metabolic safety profiles. ITCS should be considered first-line therapy given its excellent efficacy and absence of systemic metabolic complications. Future research should focus on larger randomized controlled trials with standardized outcome measures to establish evidence-based treatment protocols for this vulnerable population.