We’re Watching the World Go Blind

Three researchers say eye care accessibility around the globe isn’t keeping up with an aging population, posing challenges for eye care professionals over the next 30 years.

5:00 AM

Author | Jordyn Imhoff

Pupil of eye with world map being reflected in the eye

As the global population grows and ages, so does their need for eye care. But according to two new studies published in The Lancet Global Health, these needs aren't being met relative to international targets to reduce avoidable vision loss.

As 2020 comes to a close, an international group of researchers set out to provide updated estimates on the number of people that are blind or visually impaired across the globe, to identify the predominant causes, and to illustrate epidemiological trends over the last 30 years.

LISTEN UP: Add the new Michigan Medicine News Break to your Alexa-enabled device, or subscribe to our daily updates on iTunes, Google Play and Stitcher

"This is important because when we think about setting a public health agenda, knowing the prevalence of an impairment, what causes it, and where in the world it's most common informs the actions that key decision makers like  the WHO and ministries of health take to allocate limited resources," says Joshua Ehrlich, M.D., M.P.H., a study author and ophthalmologist at Kellogg Eye Center.

The study team assesses a collection of secondary data every five years, undertaking a meta-analysis of population-based surveys of eye disease assembled by the Vision Loss Expert Group and spanning from 1980 to 2018.

Creating a blueprint

A study like this poses challenges since regional populations vary in age. 

"For example, the population in some Asian and European countries is much older on average than the population in many African nations. Many populations are also growing older over time. A direct comparison of the percentage of the population with blindness or vision impairment wouldn't paint a complete picture" says Ehrlich, who is also a member of University of Michigan's Institute for Healthcare Policy and Innovation, explains.

To address this issue, the study looked at age-standardized prevalence, accomplished by adjusting regional populations to fit a standard age structure.

"We found that the age-standardized prevalence is decreasing around the world, which tells us eye care systems and quality of care are getting better," says C.S. Mott Children's Hospital's Monte A. Del Monte, M.D., a study author and pediatric ophthalmologist at Kellogg Eye Center. "However, as populations age, a larger number of people are being affected by serious vision impairment, suggesting we need to improve accessibility to care and further develop human resources to provide care."

In fact, the researchers found that there wasn't any significant reduction in the number of people with treatable vision loss in the last ten years, which paled in comparison to the World Health Assembly Global Action Plan target of a 25% global reduction of avoidable vision loss in this same time frame.

Although findings varied by region globally, cataracts and the unmet need for glasses were the most prevalent causes of moderate to severe vision impairment. Approximately 45% of the 33.6 million cases of global blindness were caused by cataracts, which can be treated with surgery.

Refractive error, which causes a blurred image resulting from an abnormal shape of the cornea and lens not bending light correctly, accounted for vision loss in 86 million people across the globe. This largest contributor to moderate or severely impaired vision can be easily treated with glasses.

We face enormous challenges in treating and preventing vision impairment as the global population grows and ages, but I'm optimistic of a future where we will succeed because of the measures we take now to make a difference.

Joshua R. Ehrlich, M.D., M.P.H.

Also important, vision impairment due to diabetic retinopathy, a complication of diabetes that affects eyesight, was found to have increased in global prevalence.

"This is another condition in which we can prevent vision loss with early screenings and intervention," says study author Alan L. Robin, M.D., a collaborating ophthalmologist at Kellogg Eye Center and professor at Johns Hopkins Medicine. "As diabetes becomes more common across the globe, this condition may begin to affect younger populations, as well."

Looking to 2050

"Working as a global eye care community, we need to now look at the next 30 years," Ehrlich says. "We hope to take these findings and create implementable strategies with our global partners through our Kellogg Eye Center for International Ophthalmology so fewer people go blind unnecessarily."

In an effort to contribute to the WHO initiative VISION 2020: The Right to Sight, the researchers updated estimates of the global burden of vision loss and provided predictions for what the year 2050 may look like.

They found that the majority of the 43.9 million people blind globally are women. Women also make up the majority of the 295 million people who have moderate to severe vision loss, the 163 million who have mild vision loss and the 510 million who have visual impairments related to the unmet need for glasses, specifically poor near vision.

MORE FROM MICHIGAN: Sign up for our weekly newsletter

By 2050, Ehrlich, Del Monte, and Robin predict 61 million people will be blind, 474 million will have moderate and severe vision loss, 360 million will have mild vision loss and 866 million will have visual impairments related to farsightedness.

"Eliminating preventable blindness globally isn't keeping pace with the global population's needs," Ehrlich says. "We face enormous challenges in treating and preventing vision impairment as the global population grows and ages, but I'm optimistic of a future where we will succeed because of the measures we take now to make a difference."

Both studies were funded by Brien Holden Vision Institute, Fondation Théa, Fred Hollows Foundation, Bill & Melinda Gates Foundation, Lions Clubs International Foundation, Sightsavers International and the University of Heidelberg.

Papers Cited: "Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study," The Lancet Global Health. DOI: 10.1016/S2214-109X(20)30489-7

"Trends in prevalence of blindness and distance and near vision impairment over 30 years: an analysis for the Global Burden of Disease Study," The Lancet Global Health. DOI: 10.1016/S2214-109X(20)30425-3


More Articles About: Lab Report All Research Topics Community Health Gender Diabetes Management Eye Disorders Vision Testing Health Care Delivery, Policy and Economics Health Care Quality Kellogg Eye Center
Health Lab word mark overlaying blue cells
Health Lab

Explore a variety of health care news & stories by visiting the Health Lab home page for more articles.

Media Contact Public Relations

Department of Communication at Michigan Medicine

[email protected]

734-764-2220

In This Story
Joshua Ehrlich Josh Ehrlich

Associate Professor

Stay Informed

Want top health & research news weekly? Sign up for Health Lab’s newsletters today!

Subscribe
Featured News & Stories orange cells floating squiggly lines coming out of it with blurred blue and purple colors
Health Lab
Clinically deployed AI guidance for preventing C. difficile spread
AI guidance for clinicians aimed at reducing the spread of C.diff was deployed for the first time in a hospital setting, according to a University of Michigan-led study.
outline drawing of pancreas on beige screen with green orange yellow and pink
Health Lab
Avoiding recovery delays with hospitalized pancreatitis
Acute pancreatitis is among the most common gastrointestinal conditions requiring inpatient hospital care in the United States. Balancing the signaling of the interleukin-22 protein and interleukin-22 binding protein is crucial to recovery from acute and chronic pancreatitis.
ultrasound on skin
Health Lab
Simple muscle ultrasound may detect early prediabetes
A simple ultrasound of a patient’s thigh or shoulder muscle may detect insulin resistance before it progresses to type 2 diabetes or even prediabetes. In a study, Michigan Medicine researchers performed muscle ultrasounds on 25 patients who were also evaluated for insulin resistance.
algae green spread all over lake by forest edge from high view
Health Lab
Living near harmful algal blooms reduces life expectancy with ALS
Living close to cyanobacterial harmful algal blooms — which are present nationwide but are more common in coastal and Great Lake states — heightens the rate of dying from amyotrophic lateral sclerosis, or ALS, a study suggests.
teen by self in room listening to music and family with young kid eating out
Health Lab
Many parents struggle letting teens have independence on family vacations
One in five parents say they’ve never allowed their teen to be away from them during a trip.
father and son standing together and book cover
Health Lab
One doctor’s American dream: to stop hate
Asian-American history is American history. William D. Chey shares his immigrant father’s legacy, his own experience and calls on youth to practice the values of diversity, equity and inclusion throughout their lives.