Published: 11 March 2024
What is a lazy eye?
Amblyopia, more commonly known as a ‘lazy eye’, is a neurodevelopmental eye condition that affects as many as four in 100 children. It occurs when the vision in one eye does not develop properly; a disconnect between how the brain and eye work together means the brain is unable to process the visual signal from the affected eye.
The condition can be triggered by a squint or being long-sighted, but many children don’t notice anything is wrong as their vision is most often reduced in only one eye. This means that the majority of children are only diagnosed when having their first eye test at around four or five years old.
The study design
This study aimed to investigate the association between amblyopia and a range of health conditions.
The study analysed data from 126,399 adults who were part of the United Kingdom Biobank and had undergone an eye test. Participants were asked:
- if they were treated for amblyopia in childhood
- if they still had in amblyopia in adulthood
- if they had a medical diagnosis of
- diabetes
- high blood pressure
- cardiovascular diseases such as heart attack
- cerebrovascular disease such as stroke.
The following measurements were also collected from participants:
- BMI
- blood glucose
- cholesterol levels.
The results
Of the 3,238 participants who had amblyopia as a child, 82% had persistent reduced vision in one eye as an adult. Of these participants, the study found they had:
- 29% higher odds of developing diabetes
- 25% higher odds of experiencing hypertension
- 16% higher odds of having obesity
- an increased risk of heart attack, even when other risk factors were taken into account
For participants who had a ‘lazy eye’ as children but were no longer affected as adults the correlations followed the same direction but were not as strong.
Dr Siegfried Wagner from UCL Institute of Ophthalmology and Moorfields Eye Hospital said: “Vision and the eyes are sentinels for overall health – whether heart disease or metabolic dysfunction, they are intimately linked with other organ systems. This is one of the reasons why we screen for good vision in both eyes.
“We emphasise that our research does not show a causal relationship between amblyopia and ill health in adulthood. Our research means that the ‘average’ adult who had amblyopia as a child is more likely to develop these disorders than the ‘average’ adult who did not have amblyopia. The findings don’t mean that every child with amblyopia will inevitably develop cardiometabolic disorders in adult life.”
The implications
A recent report from the Academy of Medical Sciences, which involved some of the present study’s researchers, recommended urgent action to address the declining physical and mental health of UK children under five.
The team hopes that this study will help reinforce this message and highlight how child health lays the foundations for adult health.
Corresponding author Professor Jugnoo Rahi from UCL Great Ormond Street Institute for Child Health, UCL Institute of Ophthalmology and Great Ormond Street Hospital said: “It is rare to have a ‘marker’ in childhood that is associated with increased risk of serious disease in adult life, and also one that is measured and known for every child – because of population screening.
“The large numbers of affected children and their families may want to think of our findings as an extra incentive for trying to achieve healthy lifestyles from childhood.”
Made possible by NIHR Infrastructure
The study was funded by the Medical Research Council and the Ulverscroft Foundation. It was led by UCL and carried out in collaboration with the University of the Aegean, University of Leicester and King’s College London.
The study relied upon NIHR support:
Dr Siegfried Wagner is a Senior Research Fellow at Moorfields Eye Hospital and UCL Institute of Ophthalmology and is supported by NIHR Moorfields BRC.
Professor Jugnoo Rahi is a Professor of Ophthalmic Epidemiology at UCL Great Ormond Street Institute of Child Health, which is supported by NIHR GOSH Biomedical Research Centre (BRC). She is also an academic at the Institute of Ophthalmology (IoO) UCL, which is supported by NIHR Moorfields BRC. She is an NIHR Senior Investigator.
Read the full paper in eClinicalMedicine.