Tinnitus and Obstructive Sleep Apnea

Tinnitus is a phenomenon of perceiving sounds in the absence of external auditory source, and it greatly influences the quality of paitent’s life. Although the pathophysiology of tinnitus remains unclear, recent studies have suggested a possible relationship between tinnitus and sleep disorder, mainly obstructive sleep apnea (OSA). In this context, this review study aimed to unravel the possible hypotheses regarding the correlation between tinnitus and OSA and to propose comprehensive mechanisms by which OSA may contribute to the occurrence or exacerbation of chronic tinnitus. Four main hypotheses are: 1) OSA can cause hearing loss, which consequently provokes tinnitus, 2) OSA-induced snoring sound can directly affect auditory organs and cause tinnitus, 3) OSA can worsen sleep quality, which could lead to tinnitus, and 4) tinnitus can be caused by a continuous positive airway pressure machine itself. Further research to evaluate chronic tinnitus with objective testing methods such as neuroimaging modalities or biomarkers is crucial to elucidating the correlation between OSA and tinnitus and apply into clinical treatment.