EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/194331
68 EW GLAUCOMA October 2011 February 2013 Sleep disorders linked to glaucoma, floppy eyelid syndrome by Michelle Dalton EyeWorld Contributing Writer A spate of new studies has rejuvenated the interest in the association between these disorders T hink sleeping disorders and ocular disorders are two completely separate occurrences? Maybe not, if three recently published articles1-3 are any indication. Obstructive sleep apnea (OSA) has been associated with a variety of ocular disorders, from floppy eyelid syndrome (FES) to keratoconus to infectious keratitis to glaucoma.3 OSA and glaucoma Chin-Chun Lin, MA, and colleagues used a national, population-based dataset in Taiwan to determine the risk and prevalence of open-angle glaucoma (OAG) among patients with OSA over the course of 5 years.3 Ahmad A. Aref, MD, reported on nighttime events that might lead to the development or progression of glaucomatous optic neuropathy.2 Patients with OSA "were independently associated with a 1.67 times increased risk of OAG diagnosis within the first 5 years after their diagnosis," Prof. Lin wrote. The group noted two theories on the re- lationship exist—one suggesting the increased IOP and "stretching of the lamina cribrosa is the reason for glaucoma," but that obesity (or at least an increased body mass index) is also thought to be related to direct damage of the optic nerve, and an overwhelming majority of patients with OSA are overweight. The second theory suggests hypoxia can cause direct damage to the optic nerve and that the recurrent hypopnea characteristic of OSA is partially responsible for optic nerve head perfusion, the group noted. "There is certainly enough early evidence to suggest that OSA plays a role in the progression of glaucoma," said Dr. Aref, assistant professor of ophthalmology, Illinois Eye & Ear Infirmary, Department of Ophthalmology & Visual Sciences, University of Illinois at Chicago. He noted these kinds of large, retrospective cohort studies "have some methodological limitations. They rely on billing diagnoses that are subject to underdiagnosis"—both OSA and glaucoma fall into this category because of their slowly progressive and largely asymptomatic nature. Case-control studies, on the other hand, "are better designed with prospectively diagnosed individuals with glaucoma, OSA, or both," he said. OSA and FES A few theories on the causal relationship between OSA and FES exist.