Dose-response relationship of aspirin and sudden sensorineural hearing loss risk in type 2 diabetes

Abstract

Background

Sudden sensorineural hearing loss (SSNHL) affects 5 to 27 per 100,000 annually, often leading to permanent hearing loss and reduced quality of life. Type 2 diabetes (T2D) may heighten SSNHL risk via vascular damage. Aspirin is used in T2D for cardiovascular protection, yet its effect on SSNHL is uncertain and may vary by dose.

Methods

We conducted a cohort study using Taiwan's National Health Insurance Research Database to assess SSNHL risk associated with aspirin use in T2D patients. Eligible T2D patients were categorized based on cumulative aspirin exposure (cDDD ≥ 28 vs. <28) and matched on key covariates. Cox proportional hazards models and Fine and Gray's competing risk model assessed SSNHL and all-cause mortality across quartiles of cumulative aspirin dose.

Results

Among 51,657 matched pairs, SSNHL incidence was similar between aspirin users and non-users, but a dose-response effect emerged: patients in the highest cDDD quartile (Q4) had a significantly reduced SSNHL risk (adjusted HR 0.43, 95 % CI, 0.32–0.58; p < 0.0001), while lower quartiles showed increased risks. Aspirin use was associated with reduced all-cause mortality (adjusted HR 0.77, 95 % CI, 0.75–0.80). Fine and Gray's competing risk model confirmed that this reduction in mortality did not bias the observed dose-dependent protective effect of aspirin on SSNHL. Even after accounting for competing mortality risk, aspirin's protective association with SSNHL remained significant in the highest quartile (Q4, aHR 0.46, 95 % CI, 0.34–0.62; p < 0.0001), indicating an independent protective effect.

Conclusions

Our findings suggest a dose-dependent relationship where high cumulative doses of aspirin reduce SSNHL risk in T2D patients, underscoring the importance of adequate dosing for potential protective effects. Further research is necessary to clarify this dose-response relationship.