Alzheimer’s patients' sight significantly worse, research finds

Further research due on whether supplements can halt decline in cognitive function

Researchers have found that Alzheimer’s patients have “significantly worse” vision than others in their age group and are more likely to be deficient in key nutrients in the eye.

The multi-disciplinary team from the Vision Research Centre at Waterford Institute of Technology also discovered it’s possible to improve the vision of patients with Alzheimer’s disease by providing supplements that include the carotenoid macular pigment.

The findings allow the possibility for further groundbreaking research and have been published in the Journal of Alzheimer’s Disease following funded by the UK-based Howar Foundation.

Future phases of the research project, led by Prof John Nolan and Prof Stephen Beatty with Prof Riona Mulcahy of the Age-Related Care Unit at University Hospital Waterford (UHW), will follow a cohort of patients with early signs of cognitive decline over a three-year period.


This will be aimed at investigating whether taking specific supplements can arrest the decline in cognitive function, and possibly improve it.

Other members of the research tam include Dr Alan Howard of the Howard Foundation in Cambridge, who created the Cambridge Diet.

Common dementia

Prof Nolan, a Fulbright Scholar and European Research Council-funded Fellow, said Alzheimer’s is the single most common form of dementia, affecting an estimated 48,000 people in Ireland.

“In the absence of a cure for Alzheimer’s, it is vital that we look at risk factors and establish patterns between Alzheimer’s disease and other conditions,” he said.

“What our research has found is that patients with Alzheimer’s disease not only have lower cognition but also considerably poorer vision compared to their peers of the same age without Alzheimer’s.

“Furthermore, we have found that those with Alzheimer’s are significantly lacking in lutein, zeaxanthin and meso-zeaxanthin. These nutrients are known as dietary carotenoids and at the back of the eye where they are vitally important, they are referred to as macular pigment.”

The team was keen, he said, to establish whether it was possible to help restore some of the vision lost in those with Alzheimer’s.

“Our trials using supplements that are rich in carotenoids found that patients did indeed experience improved vision as their macular pigment was boosted.”

‘Particularly exciting’

Prof Beatty said it was “particularly exciting” to see clinically meaningful improvements in the eyesight of Alzheimer’s patients who received supplements with carotenoids for six months.

“The research outcomes support the view that the Alzheimer’s patients in the study are well capable of responding to and benefiting from carotenoids but have not had them sufficiently present in their diet.

“At a societal level, this also serves to underline once again the importance of a diet rich in fruit and vegetables in reducing our risk of various debilitating conditions as we get older.”

Prof Mulcahy, who works with Alzheimer’s patients at UHW, said there is now a solid research basis to build from.

“Given the growing prevalence of Alzheimer’s and our ageing population, there is a real urgency to make progress in this field and that challenge brings exciting opportunities to collaborate with colleagues from other disciplines.”