If current projections hold, about half of the world’s population will be at lifelong risk of permanent blinding conditions.
This statistic isn’t meant to scare you into booking your annual eye exam—though you should probably get that appointment on the books.
Rather, it’s the basis for groundbreaking studies about myopia within the University of Houston’s ophthalmic research program that have helped the University land 35 active awards from the National Health Institute's National Eye Institute.
Receiving these NEI awards is a significant feat, as the application process is the most competitive research arena in the world, according to Michael Twa, dean of UH’s College of Optometry.
“Achieving a National Eye Institute grant is a career achievement for any investigator," notes Twa. “Only a few hundred new grants are awarded each year.”
Ironically, it’s the University’s foresight that secured this highly sought funding.
Myopia, commonly referred to as “nearsightedness,” is a condition that occurs when the eye grows too long, causing objects in the distance to appear blurry.
And while we have temporary, practical fixes for this through standard glasses and contact lenses, the American Optometric Association reports that as of 2020, more than 40% of Americans are myopic—a number that is rapidly rising, particularly among school-aged children.
The layman’s takeaway here is straightforward: So, more Americans will be using these tried-and-true visual aids in the future. No big deal, right?
Focusing on the Culprits
The problem is that myopia doesn’t just cause blurry vision. It creates a lifetime risk for more serious eye conditions, like myopic macular degeneration, glaucoma and retinal detachment—which can lead to permanent vision loss.
In short, myopia is a condition that is best avoided altogether. But that’s not exactly realistic.
While the exact causes of myopia are difficult to pinpoint, most researchers will agree there are three likely culprits behind its growing prevalence among kids: genetics, increased time on digital screens and less time spent outside.
The first two are no-brainers. Interestingly though, several longitudinal studies show children who spend more time outdoors, regardless of whether their parents are myopic, have a lower risk of developing nearsightedness.
Even with this insight, no “miracle cure” exists for myopia.
David Berntsen, associate professor of optometry and chair of the UH College of Optometry’s clinical sciences department, doesn’t aim to cure myopia—yet. Serving as principal investigator of the UH clinic site and on the executive committee for the Bifocal Lenses In Nearsighted Kids (BLINK) study and the BLINK2 study, Berntsen and his collaborators at The Ohio State University’s College of Optometry are instead evaluating a new type of contact lens to correct and slow the progression of myopia in young children.
The BLINK Study began as a multi-center, randomized three-year clinical trial of 294 children, with Berntsen’s team at UH following 150 children ages 7 to 11 and his colleagues at Ohio State following another 144 children. In the study, participants were randomly assigned to wear either standard soft contact lenses or one of two different add power multifocal contact lenses (medium add or high add).
When the study concluded, the answer was clear: Add power, otherwise known as the additional power over a distance prescription, matters. Berntsen and his collaborators found that the participants assigned the high-add multifocal contact lenses had slower myopic progression.
With research well underway in the second leg of the study, the BLINK2 study builds on the initial research findings to identify the “why.”
“We know the lenses work,” Berntsen says. “But our most recent findings are pointing to another likely cause of these lenses’ success other than where they’re focusing the light.”
According to Berntsen, for about the last decade, that light focusing has been the hypothesis as to why the lenses work. But, there haven’t been studies that concurrently measure some of the things these lenses affect to give a definitive answer on what specifically is causing the myopia growth reduction.
“But it's a major step to know these certain types of contact lenses are able to slow progression,” Berntsen acknowledges.
Refining the Look of Success
BLINK2 is a three-year study following the same cohort of children from the initial BLINK study, and it’s notable for more than a few reasons. The original three-year BLINK study achieved a 98% retention rate, which far exceeds the national research retention rate of 82%.
Because of this, Berntsen and his colleagues were able to continue monitoring these now high school-aged participants to understand what happens when patients stop treatment—and how these specialized lenses continue to play a part in their myopic growth reduction.
For the first two years of the BLINK2 study, all participants wore the high-add multifocal lenses that were found to slow myopia progression. Participants were also instructed to wear a watch-like light meter that monitors their exposure to varying indoor and outdoor light levels. Concurrently, their parents were instructed to complete self-reported questionnaires on things like their child’s amount of near work activities and time spent outdoors.
The third and last year of the BLINK2 study is determining if there is a change in myopia progression when all children are switched to standard contact lenses to determine if the benefit remains after discontinuing multifocal contact lens wear.
“For any myopia management treatment to be successful,” Berntsen noted, “It is important that the benefit remains once the patient stops using the treatment when they are older.”
From there, he hopes results from BLINK2 will help to identify factors that may help optimize the efficacy of the contact lenses and other optical treatments to slow myopia progression.
While these types of myopia studies aren’t proprietary to UH, the institution is identifying key gaps in our knowledge about myopia and inspiring additional research both within the program and across the nation.
In the Near Future
Currently, Berntsen and his colleagues at Ohio State have a planning grant from the NEI to lay the groundwork for a future multi-center clinical trial grant application. They want to determine whether low-concentration atropine eyedrops can be used to delay the onset of nearsightedness in kids who are most at risk of developing myopia.
Berntsen’s findings might not pave the way to an easy cure, but that’s not the point. Conducting studies like these are essential to ensure that we can respond to potential public health crises, like global vision loss, before they happen.
While data analysis for BLINK2 is still in its final stages, Twa advises that the rigor of Berntsen’s research, and his preliminary findings, cannot be understated.
"The medications, the contact lenses, the glasses—all these strategies are meant to curb myopia, and Dr. Berntsen’s studies are designed to ask and answer questions fairly about which ones work,” Twa explained. “I think the results sometimes are disturbing to people because they're at odds with what folks have been led to believe, or what they would like to believe. And that's what good science does. It's juicy. It stirs the pot. It asks the right questions, and it debunks conventional thinking sometimes, but it should.”