British scientists develop simple eye test that could predict death

British scientists develop simple eye test that could predict death

A simple eye test that predicts death from cardiovascular disease has been developed by British scientists.

It combines artificial intelligence (AI) with scans of the retina, the membrane at the back of the eye that contains light-sensitive cells.

The technique could lead to a screening program that would allow drugs and lifestyle changes to be prescribed decades before symptoms appear.

Lead author, Professor Alicja Regina Rudnicka, from St George’s University of London, said the test is cheap, accessible and non-invasive.

People at risk of stroke, heart attack and other circulatory conditions could undergo artificial intelligence-enabled retinal vasculometry (RV) during routine visits to the optician.

Prof Rudnicka said: “It has the potential to reach a higher proportion of the population in the community due to ‘high street’ availability.

“RV offers an alternative predictive biomarker to traditional risk scores for vascular health without the need for blood sampling or blood pressure measurement.

“It is very likely to help prolong disease-free status in an increasingly aging population with increasing comorbidities, and help minimize health care costs associated with lifelong vascular diseases.”

An algorithm called Quartz was developed based on retinal images of tens of thousands of Britons aged 40 to 69.

It focused on the width, area and curvature, or tortuosity, of tiny blood vessels called arterioles and venules.

Quartz’s performance was compared to the widely used Framingham Risk Scores framework, both separately and jointly.

The health of all participants was followed for an average of seven to nine years, during which time there were 327 and 201 circulatory disease deaths among 64,144 UK Biobank and 5,862 EPIC-Norfolk participants respectively.

In men, arteriolar and venular width, tortuosity, and width variation emerged as important predictors of death from circulatory disease.

In women, arteriolar and venular area and width and venular tortuosity and width variation contributed to risk prediction.

The predictive influence of retinal vasculature on death from circulatory disease interacted with smoking, drugs to treat high blood pressure, and previous heart attack.

Overall, these predictive models, based on age, smoking, medical history and retinal vasculature, recorded between half and two-thirds of circulatory disease deaths in those most at risk.

And retinal vasculature models captured around 5 per cent more cases of stroke in UK Biobank men and 8 per cent more cases in UK Biobank women and 3 per cent more cases among EPIC-Norfolk men who were most in are at risk, but almost 2 percent fewer cases among EPIC-Norfolk women.

And Framingham Risk Scores captured more cases of heart attack among those most at risk.

Retinal imaging is already common practice in the UK and the US, the researchers point out.

Prof Rudnicka said: “Retinal vasculature is a microvascular marker, and therefore offers better prediction for circulatory mortality and stroke compared to heart attack which is more macrovascular, except perhaps in women.

“In the general population, it could be used as a non-contact form of systemic vascular health monitoring, to triage those at medium-high risk of circulatory mortality for further clinical risk assessment and appropriate intervention.”

In the UK, for example, it can be included in the primary care NHS Health Check for those between 41 and 74, they suggest.

Dr. Ify Mordi and Dr. Emanuele Trucco, from the University of Dundee, who were not involved in the study, said that using retinal vasculature changes to inform overall cardiovascular risk “is certainly attractive and intuitive.”

They said: “Using retinal screening in this way would likely require a significant increase in the number of ophthalmologists or otherwise trained assessors.

“What is needed now is for ophthalmologists, cardiologists, primary care physicians and computer scientists to work together to design studies to determine whether using this information improves clinical outcome, and, if so, to work with regulatory bodies, scientific societies and health systems to optimize clinical workflows and enable practical implementation in routine practice.

The study is in the British Journal of Ophthalmology.