Cataract surgery improves cognitive ability, mood and sleep patterns in patients with Alzheimer’s disease, according to a study presented at the American Academy of Ophthalmology’s 2011 Annual Meeting in Orlando.

In this study, researchers evaluated 38 patients with debilitating cataract in at least one eye and who exhibited mild dementia secondary to Alzheimer’s disease. All patients underwent cataract surgery and IOL implantation, which yielded a dramatic improvement in both near and distance vision in all but one individual.

A neuropsychologist analyzed each patient’s mood, behavior, cognitive abilities and autonomy level one month before and three months after cataract surgery. At the three-month postoperative follow-up, cognitive status and overall perception improved in 25% of patients. Also, depression symptoms decreased in most patients. However, none of the patients demonstrated increased autonomy following surgery.

Interestingly, the researchers also found that the majority of patients experienced improved sleep patterns and fewer nighttime disturbances following surgery. The authors suggested that, following cataract removal, levels of melatonin often become normalized, which could help improve sleep quality.

“We wanted to learn whether significant vision improvement would result in positive mood and behavior changes, or might instead upset these patients’ fragile coping strategies,” said lead author Brigitte Girard, M.D., professor of ophthalmology at Tenon Hospital in Paris. “In future studies, we intend to learn what factors, specifically, led to the positive effects we found, so that we can boost the quality of life for Alzheimer’s patients, their families and caregivers.”

Girard B, Chouard B, Levy P, Laroche L. Does cataract surgery improve outcomes for Alzheimer disease patients? Paper presented at the American Academy of Ophthalmology Annual Meeting, Orlando. October 25, 2011.