Evaluation of vestibular evoked myogenic potentials responses in patients with severe obstructive sleep apnea before and after continuous positive airway pressure therapy.

Abstract

Study objectives: To investigate the diagnostic role of vestibular evoked myogenic potential (VEMP) in detecting potential damage to the otolithic organs and brainstem in patients with obstructive sleep apnea syndrome (OSAS) and evaluate the effect of continuous positive airway pressure (CPAP) therapy on the vestibular system through VEMP measurements.

Methods: This single-center, prospective study included 51 patients with severe OSAS (102 ears) and 20 controls without OSAS (40 ears). Cervical and ocular VEMP tests were administered to both groups. For patients with OSAS, VEMP tests were repeated after three-month CPAP therapy. Pre- and post-treatment VEMP data were compared between the groups.

Results: Patients with OSAS had significantly lower response rates of both ocular and cervical VEMP compared to controls (p=0.003 and p=0.027, respectively). In ocular VEMP, prolonged p1 and n1 latencies, shortened p1-n1 interpeak latencies, and decreased amplitudes were observed (p<0.0001 for all). In cervical VEMP, prolonged n1 and p1-n1 interpeak latencies and reduced amplitudes were noted (p<0.0001 for all), while no significant changes were observed in p1 latency. Significant post-treatment improvements were detected in ocular VEMP parameters, including n1 latency, p1-n1 latency, and amplitudes (p<0.0001, p=0.001, and p=0.001, respectively). Similarly, significant post-treatment improvements were observed in cervical VEMP parameters, namely n1 latency, p1-n1 latency, and amplitudes (p<0.0001, p<0.0001, and p=0.003, respectively). There was no significant change in p1 latency.

Conclusions: Subclinical abnormalities in otolithic organs and the brainstem in severe OSAS could be detected early using non-invasive VEMP testing. VEMP tests also revealed that a three-month CPAP therapy ameliorated these vestibular system abnormalities.