Influence of obstructive sleep apnea on auditory event-related potentials.

Purpose: To evaluate the influence of obstructive sleep apnea (OSA) on the P300 response of auditory event-related potentials (ERPs) and to correlate the electrophysiological findings with OSA severity.

Methods: Patients with no OSA and mild, moderate, and severe OSA according to polysomnography (PSG) with normal hearing and no comorbidities were studied. Individuals with a body mass index (BMI) ≥ 40 kg/m, hypertension, diabetes, dyslipidemia, the use of chronic medications, and a risk of hearing loss were excluded. All patients underwent full PSG and auditory ERP measurement using the oddball paradigm with tone burst and speech stimuli. For P300 analysis (latencies and amplitudes), normal multiple linear regression models were adjusted with the groups (No OSA, Mild OSA, Moderate OSA, Severe OSA), age, BMI, and Epworth score as explanatory variables.

Results: We studied 54 individuals (47 males) aged 35 ± 8 years with a BMI of 28.4 ± 4.3 kg/m. Patients were divided according to the apnea-hypopnea index (AHI) derived from PSG into no OSA (n = 14), mild (n = 16), moderate (n = 12), and severe OSA (n = 12) groups. Patients with severe OSA presented prolonged P300 latencies with tone burst stimuli compared to patients with no OSA and those with mild and moderate OSA.

Conclusion: Severe OSA is associated with impairment of the P300 response of auditory ERPs, suggesting a decrease in the processing speed of acoustic information that may be mediated by the level of somnolence.