Sleep apnea and eye diseases: evidence of association and potential pathogenic mechanisms.

Abstract

Eye diseases are an important group of increasingly prevalent disorders that contribute very significantly to disability and represent a considerable health burden. Some data suggest that several of these diseases may be associated with sleep-disordered breathing, mainly obstructive sleep apnea (OSA), due to intermediate mechanisms, such as intermittent hypoxia or sleep fragmentation. The aims of this systematic review were to identify and critically evaluate the current evidence supporting the existence of a possible relationship between OSA and the more relevant eye diseases as well as to evaluate the potential pathogenic mechanisms. There is a body of largely low level evidence for the association of OSA with glaucoma, nonarteritic ischemic optic neuropathy, central serous chorioretinopathy and diabetic retinopathy. Meta-analysis of available case-control studies shows that OSA increases the risk of glaucoma (pooled odds ratio: 1.50; 95% confidence interval 1.25 to 1.80; p<0.001), nonarteritic ischemic optic neuropathy (3.62; 1.94 to 6.76; p<0.001) and diabetic retinopathy (1.57; 1.09 to 2.27; p=0.02). Moreover, several pathogenic pathways have been identified, mainly related to hypoxic damage, mechanical stress, systemic inflammation, oxidative stress, sympathetic tone and endothelial dysfunction. In contrast, information about the effect of apnea-hypopnea suppression on the development and progression of eye damage is either non-existent or of a very low level of evidence. In conclusion, OSA has emerged as an additional potential risk factor for many eye diseases, although their link is weak and contradictory, so further examination is required.