Amblyopia affects an estimated 1.4 percent of children worldwide. But what if “lazy eye” was an indicator of later health problems? Previous literature has not indicated any link between amblyopia in childhood and a greater risk of cardiometabolic dysfunction in adulthood. Now, a newly published study in The Lancet – conducted by Siegfried Wagner, Vasiliki Bountziouka, Pirro Hysi, and Jugnoo Rahi on behalf of the UK Biobank Eye & Vision Consortium – suggests otherwise, though the authors acknowledge the lack of evidence pointing to a causal relationship.
“What the study shows is that the average person who had amblyopia in childhood has a higher risk of cardiometabolic disorders in adult life – it doesn’t mean that everyone with amblyopia will develop these cardiometabolic disorders,” explains co-author Jugnoo Rahi, a practicing ophthalmologist and epidemiologist. “But it is very unusual to have a clear childhood ‘marker’ of increased risk of cardiometabolic disorders as an adult – and in the case of amblyopia, a marker that is known for every child due to whole population screening.”
How strong is the link? Patients who had amblyopia as a child had a 16-percent higher chance of becoming obese in adulthood, a 29-percent higher chance of developing diabetes, and were 25 percent more likely to develop hypertension in their adult life. An increased risk of heart attack was also noted in the study. “It would be speculation to offer reasons behind the observation,” says Rahi. “[But] we hope that knowing this association can support the efforts of affected children and their families to achieve healthy lifestyles – including exercise and healthy diets – from the outset.”
Despite the lack of evidence to support causality, Rahi believes the findings do add usefully to the existing evidence base pointing towards the importance of early life as a foundation for lifelong health. “Specifically, they uncover a potential indirect/non-vision benefit of childhood vision screening to detect amblyopia,” she says. “Since amblyopia affects between two percent and four percent of most child populations, there could be a significant impact at population level. It would be good to investigate if knowledge of the association was helpful to affected children as they grow up in terms of motivating or maintaining healthy lifestyles, as that would be an important route to a population benefit via child vision screening.”
This article first appeared in The New Optometrist.
