Cataract Surgery Improves Sleep
Keeping with the theme of June being Cataract Awareness Month, this week’s blog will discuss a potential benefit of cataract surgery that many do not think of, improved sleep and cognitive performance.
We all think of how the development of cataracts causes one’s vision to become blurry or may cause problems with night driving. Removing the cataract and replacing it with a clear lens implant will help both of these issues. Cataract surgery cannot only provide one with clearer vision, but it can also minimize the need for glasses or contact lenses to see one’s best.
A recent study in the Journal of American Medical Association Ophthalmology has shown that replacing the cloudy cataract lens with a clear lens implant improves the sleep pattern of patients. By allowing more light to enter the eye after cataract surgery, one’s circadian rhythms improve. As a result, these patients spent more time in deep sleep after cataract surgery. A secondary benefit of this improved sleep pattern after undergoing cataract surgery is that these patients also demonstrated improved cognitive performance when tests were giving in the morning after they woke up.
As one ages, our natural lens gradually clouds to a state where it appears a yellow-brownish color upon examination. This process results in the lens gradually filtering out more and more light as one ages. Not only is the amount of light that travels to the back of the eye reduced, but the spectrum of light that reaches the retinal tissue in the back of the eye is also altered. In some instances the amount of light reaching the back of an eye with a cataract may be reduced to about 10 percent of what reaches the back of a young adult’s eye. This decrease in the amount and wavelength of light that hits the retinal tissue in the back of the eye leads to an increase in melatonin. Patients who had undergone cataract surgery with implantation of a clear lens did not have this increase in melatonin. Their response was more similar to that of younger adults.
Although, this study only consisted of 29 patients, it does provide evidence of an additional benefit that cataract surgery can have for patients beyond improved vision.