Prevalence of Glaucoma in Patients With Moderate to Severe Obstructive Sleep Apnea

Ocular Morbidity and Outcomes in a 3 Year Follow-up Study

SP Hashim; FA Al Mansouri; M Farouk; AA Al Hashemi; R Singh

Disclosures

Eye. 2014;28(11):1304-1309. 

In This Article

Abstract and Introduction

Abstract

Purpose This study was conducted to investigate the prevalence and progression of glaucoma in patients receiving treatment for obstructive sleep apnea (OSA). We also investigated whether there is an association between severity of OSA and the incidence of glaucoma.

Methods A total of 39 patients aged >30 years who had been diagnosed with moderate and severe OSA in the sleep clinic at Hamad General Hospital were assessed for the presence of glaucoma. The severity of OSA was graded as mild, moderate, or severe based on American Association of Sleep Medicine (AASM) criteria using the apnea hypopnea index. Before enrollment, all patients underwent a complete ophthalmic examination including serial visual field tests, optical coherence tomography (OCT) with fundus photographs, and pachymetry. Enrolled patients were followed up in the ophthalmology outpatient clinic and sleep clinic for a period of 3 years.

Results Examinations found that 8 (20.5%; 95% confidence interval (CI) 9.9–37%) of the 39 patients with OSA had glaucoma. Six (75%; 95% CI 36–96%) of these patients had normal-tension glaucoma (NTG) and two (25%; 95% CI 4.5–64.4%) patients had high-tension glaucoma. Among the 27 patients with severe OSA, 7 (25.9%; 95% CI 8–34%) had glaucoma, and among 12 patients with moderate OSA, 1 (8.3%; 95% CI 0.1–15%) had glaucoma. During the course of follow-up, two patients who previously did not have glaucoma were reclassified as NTG and two patients with glaucoma deteriorated. A higher prevalence of glaucoma in the severe OSA group compared with the moderate OSA group was found, albeit a statistically significant difference could not be attained (P=0.4).

Conclusions Our study showed that severe OSA is an important risk factor for developing glaucoma. Adequate treatment of OSA, along with optimal ophthalmic care, resulted in better control of glaucoma.

Introduction

Sleep apnea is a common disorder characterized by brief interruptions of breathing during sleep, and sleep apnea syndrome is defined as episodes of apnea and hypopnea during sleep accompanied by symptoms of functional impairment after sleep.[1]

Obstructive sleep apnea (OSA) is a type of sleep apnea that results from complete or partial collapse of the pharyngeal airway during sleep, and is characterized by brief interruptions of breathing.

OSA increases the risk for cardiovascular morbidity and mortality, and can also cause hypertension and increased insulin resistance. OSA has also been associated with daytime sleepiness, which can lead to automobile accidents.

Oxygen levels in tissues decrease significantly during sleep in patients with OSA, resulting in changes in brain metabolism and brain activation response.[2] Glaucoma is the second leading cause of blindness worldwide, and in the year 2020, an estimated 79.6 million people will be affected by the disease.[3] Glaucoma is defined as a chronic progressive optic neuropathy,[4] and it is usually asymptomatic until the disease is well advanced. Even in developed countries, only ~50% of probable glaucoma patients are officially diagnosed with the disease, and the rate of diagnosis in developing countries is probably much lower.[3] Prevalence of OSA in the general population showed wide variation, affecting men more than women. Values ranging from 3 to 7% were mentioned in various studies, and found to be higher in the studies from Asia.[5] Previous studies have shown an association between OSA and glaucoma in general and NTG in particular.[6–13] This study was conducted to investigate the prevalence and progression of glaucoma in patients receiving treatment for OSA. We also investigated whether there is an association between the severity of OSA and the incidence of glaucoma.

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