A new study found that the common eye disease affecting people aged 50 and older is not related to memory-loss disease such as dementia and Alzheimer's.
Researchers from the University of Manchester led by eye surgeon Dr. Tiarnan Keenan analyzed the medical records of 66,000 patients diagnosed with the common eye disease called "age-related macular degeneration." They also looked at the records of 168,000 Alzheimer's disease or dementia and over 7 million for comparison. They aim to know if having the eye disease causes dementia and vise versa, or none at all.
According to the National Institute of Health, age-related macular degeneration (AMD) is a common eye disease causing vision loss to the older population. It damages the macula, a small spot near the center of the retina and the part of the eye needed for sharp, central vision, which lets us see objects that are straight ahead. While the disease does not lead to total blindness, the loss of central vision can interfere with simple everyday activities, such as the ability to see faces, drive, read, write, or do close work, such as cooking or fixing things around the house. People who smoke, Caucasians, and/or has family history of the disease are most at risk.
AMD is often linked to dementia as both affects older people and have the same risk factors. However, when studied closely, the two don't have the same genetic risk factors. The researchers wanted to prove the latter belief.
After careful analysis of the medical records, the researchers found no relationship between AMD and dementia. Having any of the two diseases will not increase the risk of developing the other disease. However, they also found that patients with dementia are less likely to receive treatment if they have AMD too.
"These data provide evidence that there is no positive association between [age-related macular degeneration] and dementia or [Alzheimer's disease]," Dr. Keenan wrote in the paper.
The study was published in the Nov. 14 issue of the JAMA Ophthalmology.