Idiopathic sudden sensorineural hearing loss in patients with obstructive sleep apnea

Purpose: Obstructive sleep apnea (OSA) is characterized by recurring hypoxic-apneic events during sleep, and labyrinthine vascular compromise is a pathophysiologic hallmark of idiopathic sudden sensorineural hearing loss (ISSNHL). Some reports have discussed the relationship between OSA and hearing impairment; however, few have examined hearing prognosis in OSA and patients without OSA with ISSNHL. We aimed to investigate clinical manifestations of ISSNHL in patients with OSA, including severity of hearing loss and response to treatment. Patients and Methods: A case-control study was conducted by extracting data from the sleep center and cochlea center databases of the Chang Gung Memorial Hospital. A retrospective chart review was performed to include confirmed adult OSA patients diagnosed with unilateral ISSNHL. Age and sex-matched patients without OSA with ISSNHL were enrolled as controls. Pure-tone average (PTA) thresholds were measured at specific frequencies. Changes in PTA before and after standard treatment with oral prednisolone (1mg/kg/day for 5 days, then tapered) and between participants with OSA and without OSA were compared. Standard treatment was given to all ISSNHL patients. Results: Twenty-eight out of 8500 (0.33%) OSA patients experienced subsequent ISSNHL in 9 years. Patients with OSA (n=28) had poorer high-frequency perception in the unaffected ear than the patients without OSA (n=120), although the difference was not significant. Hearing in the affected ear among patients with OSA was comparable to that patients without OSA at individual frequencies and average, suggesting no difference in hearing loss in the affected ear between the two groups. In terms of high-frequencies (4000 and 8000 Hz) perception, patients with OSA had significantly poorer responses to steroid treatment than patients without OSA. Conclusion: ISSNHL may be one of the auditory complications associated with OSA. Patients with OSA had poorer prednisolone related hearing improvement in high frequencies than patients without OSA. Despite study limitations, OSA-related hypoxia and snoring noise is hazardous to hearing and standard treatments with CPAP is suggested in OSA patients for both holistic and auditory health.