Dizziness in OSA patients– is there a link and can CPAP treat it?
Reviewed by Aileen Lambert

This is a small study which proposes an interesting hypothesis - that in patients with both dizziness and OSA, treatment of their sleep disorder can provide resolution of their dizziness symptoms, which were otherwise refractory to standard treatment, particularly in patients with Meniere’s disease. The pathophysiological link between these two conditions is suggested to be at a cerebrovascular flow level. It is also highlighted that migraine is known to be more problematic in patients with untreated OSA. This retrospective study explores the incidence of OSA in patients who attended a dedicated dizziness clinic. The authors identified 52 adult patients with pulse-oximetry or polysomnogram-confirmed OSA who had received treatment with CPAP or uvulopalatopharyngoplasty (UVPPP). The mean Apnoea-Hypopnoea Index was 30. All patients had undergone vestibular review by a neurotologist and had vestibular testing/MRI as necessary to reach a diagnosis. Normal vestibular testing was found in 60%. Of the 52 patients, 19 had complete resolution of their dizziness symptoms following their OSA treatment, based on two-year follow-up data (called ‘Responders’ in the study). Ten patients did not have resolution of their symptoms, and the remainder had either incomplete documentation or incomplete CPAP treatment due to intolerance. When comparing this study group incidence to the normal population, the rate of vestibular migraine in this study was 10 times, Meniere’s disease was 115 times, and sudden sensorineural hearing loss (SSNHL) with vertigo 200 times that of the general population. A fourth type of dizziness symptom was described by patients in this study, which involves multiple daily bouts of non-positional internal spinning, phenotypically similar to vestibular paroxysmia. It was this type of dizziness which responded best to OSA treatment. The three patients in the responder group who had a diagnosis of Meniere’s disease had full resolution of their symptoms following OSA treatment, despite failing standard MD treatment prior to OSA intervention. Also, in the responder group, all patients with vestibular migraine had complete resolution of symptoms following CPAP (as the only added treatment). This is an early study and unsurprisingly recommends further prospective randomised controlled trials of this topic, but it is a useful reminder to screen for OSA in patients who present primarily with vestibular symptoms, and consider appropriate treatment, which may benefit both conditions.

The Clinical Spectrum of Dizziness in Sleep Apnea.
Foster CA, Machala M.
OTOL NEUROTOL
2020;41(10):1419-22.