Does Bad Sleep Cause Glaucoma?

Glaucoma is a potentially blinding eye disease with damage to the optic nerve that is sometimes associated with high pressure inside the eye. Because you cannot feel glaucoma or notice the vision loss until a very late stage, glaucoma is a sneaky and sometimes devastating disease. That's why it's important to be regularly checked by an eye doctor. A new study showed an interesting association with sleep patterns.

• If you sleep too long or not long enough, you're more likely to have glaucoma.
• Same if you fall asleep too quickly or take too long.
• And if you tend to forget things during the day, you're more likely to have glaucoma.

Importantly, an "association study" such as this one doesn't prove cause and effect. Does poor sleep cause glaucoma or the reverse? Or are they related to some other factor?