Association between remnant cholesterol and short-term hearing outcomes in sudden sensorineural hearing loss

Dyslipidemia has been implicated in the pathogenesis and prognosis of sudden sensorineural hearing loss (SSNHL). Remnant cholesterol (RC), a novel lipid parameter, predicts cardiovascular outcomes independently of traditional lipid indices, but its prognostic value in SSNHL remains unclear. We examined whether baseline RC is associated with short-term hearing outcome after systemic treatment.

We conducted a retrospective cohort study of 399 patients diagnosed with SSNHL who received standardized systemic treatment for 1-2 weeks. RC was calculated as total cholesterol - LDL-C - HDL-C. The primary endpoint was non-recovery, defined as a pure-tone average (PTA) improvement < 15 dB; sensitivity analyses used < 10 dB based on different guidelines. Multivariable logistic regression and restricted cubic spline analyses were used to evaluate associations. Patients were additionally stratified by LDL-C and RC to assess prognostic information beyond LDL-C.

Of the 399 patients, 178 (44.6%) achieved short-term hearing recovery. Higher RC was independently associated with non-recovery (adjusted OR 2.25, 95% CI 1.34-3.77; P = 0.002), and spline analyses suggested an approximately linear relationship. Findings were consistent using the 10 dB definition (adjusted OR 2.10, 95% CI 1.31-3.36; P = 0.002). Compared with low LDL-C/low RC, non-recovery odds were higher in high LDL-C/low RC (adjusted OR 1.85, 95% CI 1.17-2.95), low LDL-C/high RC (adjusted OR 3.52, 95% CI 1.37-9.06), and high LDL-C/high RC (adjusted OR 2.06, 95% CI 1.63-4.41).

Elevated RC is independently associated with poorer short-term recovery in SSNHL. RC may serve as an easily obtainable biomarker for short-term recovery stratification in SSNHL.