Results of a second major myopia study to be released this week have shown the incidence of childhood myopia among American children has more than doubled over the last 50 years.
According to a study of 9,000 Los Angeles-area children by the USC Eye Institute, the incidence of childhood myopia is increasing at ‘an alarming pace’.
The university said the findings echoed a ‘troubling trend among adults and children in Asia, where 90 percent or more of the population have been diagnosed with myopia, up from 10 to 20 percent 60 years ago’.
The Multi-Ethnic Pediatric Eye Disease Study MEPEDS, conducted by researchers and clinicians from the USC Eye Institute at Keck Medicine at USC in collaboration with the National Institutes of Health, found that the incidence of childhood myopia in the US to be greatest in African-American children, followed by Asian-American children, Hispanic/Latino and Non-Hispanic white children.
Rohit Varma, MD, MPH and director of the USC Eye Institute, said: ‘While research shows there is a genetic component, the rapid proliferation of myopia in the matter of a few decades among Asians suggests that close-up work and use of mobile devices and screens on a daily basis, combined with a lack of proper lighting or sunlight, may be the real culprit behind these dramatic increases. More research is needed to uncover how these environmental or behavioural factors may affect the development or progression of eye disease.’
From 2003 to 2011, the USCstudy provided free eye exams at USC Eye Institute clinics to more than 9,000 Los Angeles-area children aged between 6 months and 6 years.
‘In addition to being the largest pediatric eye study ever undertaken, it is the first of its kind to examine children as young as 6 months old,’ added Varma. ‘Typically, children do not undergo vision testing until they reach school age. By including younger children, we have the opportunity to identify eye diseases and their causes at the formative stages.’
USC Eye Institute researchers and clinicians collected basic health information during a home visit with the child and parents, followed by a detailed eye examination under dilation that collected more than 5,000 eye measurements for each child.