New research has found that the difference between the biological age of the retina, the light-sensitive layers of nerve tissue at the back of the eye, and a person’s actual (chronological) age is related to his risk of death. The study was published in the “British Journal of Opthalmology”.
This “retinal age gap” could be used as a screening tool, the researchers suggested. A growing body of evidence suggests that the network of small vessels (microvessels) in the retina may be a reliable indicator of the overall health of the circulatory system of the body and the brain.
Although the risks of illness and death increase with age, it is clear that these risks vary considerably between people of the same age, implying that “biological aging” is unique to the individual and may be a better indicator of current and future health, the researchers said. Several tissue, cellular, chemical and imaging indicators have been developed to capture biological aging that is out of step with chronological aging. But these techniques run into ethical and privacy issues, in addition to being often invasive, expensive and time-consuming, the researchers said.
So they turned to deep learning to see if it could accurately predict a person’s retinal age from images of the fundus, the inner back surface of the eye, and to Seeing if there was a difference between this and a person’s actual age, called the “retinal age gap”, could be linked to an increased risk of death. Deep learning is a type of machine learning and artificial intelligence (AI) that mimics the way people acquire certain types of knowledge. But unlike classical machine learning algorithms which are linear, deep learning algorithms are stacked in a hierarchy of increasing complexity.
The researchers relied on 80,169 fundus images taken by 46,969 adults aged 40 to 69, all of whom were part of the UK Biobank, a large population-based study of over half a million of middle-aged and older British residents. Some 19,200 fundus images from the right eye of 11,052 relatively healthy participants during Biobank’s initial health checkup were used to validate the accuracy of the deep learning model for the prediction of retinal age.
This showed a strong association between predicted retinal age and actual age, with an overall accuracy of 3.5 years. Retinal age difference was then assessed in the remaining 35,917 participants over an average follow-up period of 11 years.
During this period, 1,871 (5%) participants died: 321 (17%) from cardiovascular disease; 1018 (54.5 percent) from cancers; and 532 (28.5 percent) from other causes, including dementia. The proportions of “rapid aging” – those whose retina appeared older than their actual age – with retinal age differences of more than 3, 5 and 10 years were, respectively, 51%, 28% and 4.5 %.
Large retinal age gaps in years were significantly associated with 49-67% higher risks of death other than cardiovascular disease or cancer. And every one-year increase in retinal age difference was associated with a 2% increased risk of death from any cause and a 3% increased risk of death from a specific cause other than diseases. cardiovascular disease and cancer, after taking into account potentially influential factors, such as blood pressure, weight (BMI), lifestyle and ethnicity.
The same process applied to the left eyes produced similar results. This is an observational study, and as such cannot establish cause. The researchers also acknowledged that the retinal images were captured at one point in time and the participants may not be representative of the UK population as a whole.
Nevertheless, they wrote: “Our new findings have determined that retinal age difference is an independent predictor of increased risk of mortality, particularly non-[cardiovascular disease]/ non-cancer mortality. These results suggest that retinal age may be a clinically significant biomarker of aging. They added: “The retina provides a unique and accessible ‘window’ to assess the pathological processes underlying systemic vascular and neurological diseases that are associated with increased risks of mortality. “
“This hypothesis is supported by previous studies, which have suggested that retinal imaging contains information about cardiovascular risk factors, chronic kidney disease, and systemic biomarkers,” they continued. The new findings, combined with previous research, have added weight to the hypothesis that the retina plays an important role in the aging process and is susceptible to the cumulative damage of aging that increases mortality risk, they explained. . (ANI)
(This story has not been edited by the Devdiscourse team and is auto-generated from a syndicated feed.)
