Hope for Alzheimer’s: sight and smell tests could spot the symptoms sooner

Analysing patients’ eyes and sense of smell could help doctors diagnose Alzheimer’s disease years before traditional medical tests, according to new research presented at this year’s Alzheimer’s Association international conference in Copenhagen.

A group of researchers from Harvard found that greater brain cell death was linked to a worsened ability to smell. In another study, Dr Davangere Devanand from Columbia University Medical Center followed a group of elderly people in New York over six years and found that those who had initially been assessed as being poor at identifying odours were more likely to go on to develop Alzheimer’s.

Other research focused on the level of beta-amyloid detected in the eye. Beta-amyloid is a protein that clogs up the brain of sufferers years before symptoms of memory loss appear. In an Australian study, the Commonwealth Scientific and Industrial Research Organization gave participants a curcumin supplement. Because this has fluorescent properties, researchers were able to detect amyloid plaque in the eye using imaging techniques.

Paul D. Hartung, from Cognoptix, a medical technology company in Massachusetts, reported similar success with a fluorescent eye scanning system that detects beta-amyloid with the help of a special ointment applied to the lower eyelid. Brain scans confirmed that there’s a correlation between amyloid build-up in the brain and the eyes.

Existing tests to identify this type of brain damage involve scans and lumbar punctures, which are expensive, invasive, and impractical to offer to everyone who’s getting older. But most cases of Alzheimer’s aren’t detected until the symptoms are advanced, and there is no cure. That means these new options for earlier detection could not only lead to the disease being spotted sooner but to more effective treatment options in future.

There are around 44 million people around the world living with dementia, 800,000 of those in the UK. (Alzheimer’s is the most common form.) Last year, the British government hosted an international summit on dementia, with experts pledging to find a cure by 2025.

Heather Snyder, the director of medical and scientific operations at the Alzheimer’s Association said, ‘In the face of the growing worldwide Alzheimer’s disease epidemic, there is a pressing need for simple, less invasive diagnostic tests that will identify the risk of Alzheimer’s much earlier in the disease process.’

Image via Daniel Novta’s Flickr.