Fran Lowry

May 28, 2012

May 29, 2012 (Fort Lauderdale, Florida) — Patients with age-related macular degeneration (AMD) who do not respond to treatment with intravitreal anti–vascular endothelial growth factor (anti-VEGF) therapy may have untreated obstructive sleep apnea (OSA), researchers said here at the Association for Research in Vision and Ophthalmology (ARVO) 2012 Annual Meeting.

"Obstructive sleep apnea is a systemic disease that affects many organs," lead author Yoreh Barak, MD, from the University of Louisville, Kentucky, told Medscape Medical News.

"Patients can have conditions such as high blood pressure, and this can adversely affect the blood vessels in the eye. They also have apnea and hypoxia, so their oxygen levels are low. This is a very strong drive for systemic VEGF production, and that certainly hinders the local anti-VEGF treatment," he said.

Dr. Barak and his group observed that 12 of their patients with exudative AMD who failed to respond to intravitreal bevacizumab injections after 36 weeks (range, 24 to 48 weeks) had a very specific optical coherence tomography (OCT) pattern that showed high levels of subretinal fluid.

Suspecting that the patients might have OSA, the researchers sent the patients to their center's sleep laboratory and found that most of them did indeed have the condition.

Once the patients were started on continuous positive airway pressure (CPAP) therapy, their response to the bevacizumab injections improved, Dr. Barak reported.

Before CPAP therapy, fluctuations of the standardized volumetric change index (SVCI), a measure of the biological response to each intravitreal treatment, fit to a sine curve (r = .91, P = .03), with modest fluctuations and with a maximum of 6.0 ± 5.1% decrease in SVCI at 6.9 weeks after the first bevacizumab injection.

Subsequent injections failed to produce any further significant anatomic effect, Dr. Barak said.

After CPAP treatment, fluctuations of SVCI fit to a significantly different sine curve (r = .99, P = .02), with marked fluctuations with a maximum of 50.0 ± 10.5% decrease in SVCI at 42 weeks after the first bevacizumab injection.

Despite CPAP, however, the initial visual acuity (20/60 ± 20/16) was decreased significantly. At 82 weeks, the final visual acuity was 20/100 ± 20/32, Dr. Barak reported.

"Treatment of OSA yielded a subsequent impressive anatomical response, but functional improvement did not follow. Identifying and treating underlying OSA earlier in the management of exudative AMD may yield better functional outcomes," he said.

"Ophthalmologists and specialists should pay attention to the systemic condition of their patients, as all can have an enormous effect on the retina. It would be a good idea to have patients checked for OSA," he added.

Dr. Barak has disclosed no relevant financial relationships.

Association for Research in Vision and Ophthalmology (ARVO) 2012 Annual Meeting. Abstract # 2925. Presented May 8, 2012.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.

processing....