Optic nerve diseases linked to sleep disorders, study finds

Diseases of the inner retina and optic nerve may be a significant risk factor for sleep disorders, a study published in Ophthalmology suggests.

Raymond Wee, MS, and Russell Van Gelder, MD, PhD, at Washington University Medical School in St. Louis observed the sleep-wakefulness cycles of 25 visually impaired subjects who ranged in age from 12 to 20 and compared these to the cycles of 12 young subjects with normal sight. The visually impaired subjects were divided into two groups: those with optic nerve disease and those without. The activities of the subjects were monitored continuously for 14 days using a wrist-worn device.

Recent basic research has suggested that the retina contains nonvisual photoreceptors in the inner ganglion cell layer that communicate directly with the areas of the brain involved in circadian rhythms, according to a press release issued by the American Academy of Ophthalmology detailing this study.

“The study showed the subjects with optic nerve disease were 20 times more likely to have pathologic levels of daytime sleepiness, as indicated by napping, than the subjects with normal sight,” Dr. Van Gelder said in the AAO release. “They were also nine times more likely to have pathologic sleepiness than the visually impaired subjects who were blind from the non-optic nerve diseases. We suspect these patients have difficulty using daylight to synchronize their internal rhythms to the outside world.”

The study is published in the February issue of Ophthalmology.