People with poor sleep habits may be at greater risk for developing glaucoma, according to new research from Johns Hopkins University.

In this cross-sectional study, investigators included 6,784 subjects aged 40 or older who completed a sleep questionnaire from the 2005-2008 National Health and Nutrition Examination Survey. The participants were asked about the average number of hours they slept per night, how long it took them to fall asleep, whether they had been diagnosed with a sleep disorder, patterns of waking in the night, the use of sleep medication and daytime dysfunction from sleepiness, including whether they felt tired during the day.

Each subject underwent two frequency-doubling technology visual field tests per eye.

The study found the odds of disc-defined glaucoma were three times higher among those who slept for 10 or more hours per night compared with participants who slept seven hours per night. Additionally, the investigators noted the odds of disc-defined glaucoma were two times higher among individuals who fell asleep in nine minutes or less and 30 or more minutes compared with those who fell asleep within 10 to 29 minutes. The study also reported the odds of visual field defects were three times higher among subjects who slept for three hours or less per night and 10 or more hours per night compared with individuals who slept seven hours a night.

The odds of visual field defects were two times higher among those who had difficulty remembering things and three times higher among subjects who had difficulty working on a hobby due to daytime sleepiness compared with those without difficulty.

“These findings support the hypothesis that worse sleep parameters may be a risk factor for, or a consequence of glaucoma, which adds to a growing body of literature regarding sleep dysfunction in glaucoma patients,” investigators noted.