Research Shows Patients Who Have Cataracts Removed are 30% Less Likely to Develop Dementia

The key, the researchers say, may be the restoration of vision that comes with cataract surgery. The finding stems from data on 3,038 people 65 and older who were dementia-free at the start of the study and were tracked for nearly 10 years after their decision on eye surgery.

The researchers noted that visual impairment has been identified as a dementia risk factor, in part because it can lead to social isolation and decreased cognitive stimulation. But by restoring vision, they wrote, cataract surgery may help delay or prevent the development of dementia.

By comparison, the researchers found no differences in risk for dementia among people who did or did not have glaucoma surgery, which does not restore vision. Glaucoma is a condition that attacks the optic nerve. A cataract is a cloudy area that can develop in the lens of the eye, almost always caused by normal changes in the eye that come with age. Proteins in the lens tend to break down and clump together, according to the National Eye Institute, creating the cloudy area. This can lead to such symptoms as blurred vision, sensitivity to light and difficulty seeing at night.

The only treatment is surgery to remove the clouded lens and replace it with an artificial lens (called an intraocular lens), which restores vision. More than 24 million U.S. residents have cataracts, according to the American Academy of Ophthalmology, and nearly half of people who are 80 either have cataracts or have had surgery to remove them.