One morning in January 2005, Bonnielin Swenor walked up a staircase from a Metro station in Washington, D.C. She was heading to her job at a science consulting firm. She was 26 years old, had recently married and had just submitted more than a dozen applications to graduate schools in public health.

“I remember thinking, this is such a sunny day for January,” Swenor says. “When I got to the top of the steps, the sun was shining directly into my eyes. And then the afterimage of the sun never left my right eye. It just never went away. I got to my office and sat down at my desk, and I couldn’t read, couldn’t look at my email. I thought it was something in my contacts, so I took them out and washed them. But it wasn’t getting better.”

There happened to be an optometrist on the ground level of Swenor’s office building, so she went downstairs for an exam. “They told me I needed to see a retina specialist right away,” she says. “I wasn’t even sure what that meant.”

By the end of the week, Swenor had a diagnosis: myopic macular degeneration, a condition also known as pathological myopia. With this condition, the eye becomes elongated, and the resultant stretching causes the retina and other structures in the back of the eye to become thin and fragile. The thinning eventually causes a pattern of hemorrhaging, scarring and pathological blood vessel growth, all of which damage the central vision. Roughly one in 1,000 people worldwide is estimated to suffer visual impairment related to myopic macular degeneration. Older people are at greatest risk, but the condition often hits people who, like Swenor, are in the prime of life. The disease is progressive and irreversible.

Roughly a year after her diagnosis, Swenor’s second eye began to be affected. “I woke up one morning, and there was a hemorrhage in the left eye,” she says. “At that point, that was my worst nightmare. Until that point, I’d been able to tell myself, ‘At least I’ve got the one good eye.’” She left work on short-term disability and began to doubt whether she’d ever be able to build the scientific career she’d planned. “It took me a while to really absorb that these changes were permanent,” she says. “I was very depressed. It was one of the lowest periods of my life.”

Fast forward 13 years. Today Swenor is an assistant professor of ophthalmology at Johns Hopkins’ Wilmer Eye Institute. She has become one of the country’s most prominent scholars of low vision and aging. In collaboration with colleagues across Johns Hopkins and other institutions, Swenor is investigating the mechanisms through which low vision and other sensory deficits can contribute to accelerated aging. She is also exploring why so few people with failing eyesight receive low-vision rehabilitation services, which can provide the skills they need to maintain their independence and enhance their daily functioning.

“Bonnie is among the very best younger scholars I’ve ever worked with,” says Sheila West, professor of ophthalmology and vice chair for research at the Wilmer Eye Institute, who has been a faculty member at Johns Hopkins since 1971. “She has the highest standards for what she will work on and what she will do, and she’s done all of this in the face of an impairment that most people would find extremely daunting for an academic career.”

Why Should I Ask For Help?

A few months after her diagnosis, Swenor learned that she had been admitted to the M.P.H. program at the Johns Hopkins Bloomberg School of Public Health. She deferred admission for a year while she came to grips with her condition. “I distinctly remember saying to myself, ‘This just cannot be the end of my life as a scientist,’” she says.

During that year, Swenor began to receive anti-VEGF injections, one of the most common treatments for myopic macular degeneration. VEGF—vascular endothelial growth factor—is a protein that promotes the development of blood vessels in a retina affected by myopic macular degeneration. Anti-VEGF injections can’t reverse the course of the disease, but they can stabilize symptoms for a time.

In the spring of 2006, Swenor began to attend Johns Hopkins part time, making a long commute—two buses and two trains—from northern Virginia. The anti-VEGF injections had stabilized her symptoms, and she had discovered a few techniques for managing her condition. “The decision to go to school was very frightening,” she says, “but it was also a good distraction.” At this stage, she chose not to disclose her impairment to professors or fellow students. “I honestly felt like I wasn’t blind, so why should I ask for help?”

Swenor entered the M.P.H. program intending to study the relationship between nutrition and cancer risk, a long-standing interest of hers. Then, in her fourth semester, she took West’s course in the epidemiology of eye disease. “After the second class session, I met with Sheila and explained my situation,” she says. “She persuaded me to switch my research focus toward ophthalmology. That was the moment that changed my path.”

For her master’s thesis, Swenor applied her interest in nutrition and epidemiology to questions of visual impairment. She mined data from the Salisbury Eye Evaluation Study, a longitudinal study of 2,520 older adults on Maryland’s Eastern Shore. The study included extensive data about the participants’ diets, and Swenor analyzed whether consumption of seafood appeared to offer protective effects against age-related macular degeneration. Her conclusion: High levels of fish and shellfish intake were protective against the most advanced stage of the disease.

The seafood study gave Swenor a taste for epidemiological research, and it led to a much more fruitful line of inquiry. For her doctoral work at the school of public health, Swenor used the Salisbury study and other large longitudinal data sets to explore how various types of visual impairment affect older adults’ mobility over time.

This might sound like an obvious principle—of course visual impairment makes elderly people less likely to walk and more likely to fall—but, in fact, the prevalence of these problems and the mechanisms that underlie them are not fully understood by geriatricians and ophthalmologists. In a series of widely cited papers that she authored or co-authored during her doctoral study, Swenor and her colleagues explored how visual impairment can lead to fear of falling and changes in gait, which can in turn lead people to engage in less physical activity, which can in turn harm health in a host of ways.

By the time she began her doctoral study, Swenor’s eyesight had declined by another several notches. At this point, there was no choice: She had to request accommodations to complete her graduate training. In 2010, she started to seek care at Wilmer’s Lions Low Vision and Vision Rehabilitation Center, where she was advised on skills and techniques that have helped her manage her condition. But more important than those skills, she says, were the conversations she had with Judith Goldstein, the clinic’s director.

“When people first develop a disability, they tend to question themselves and struggle to find a new identity,” Swenor says. “And it was so important to talk to someone who understood and who could assure me, ‘Yes, this is hard, but here are the skills and resources that can help get you through it.’”

Around the same time that Swenor began to attend Goldstein’s clinic, she and her husband moved from Virginia to Baltimore. (Now he’s the one with the difficult commute.) They now have two young children.

“One of the most challenging parts of my day,” she says, “is when I take them to the playground. If it’s a sunny day and I haven’t happened to dress them in distinctive bright clothes, it can be hard for me to see them. There are definitely moments of panic.”

The Vision-Cognition Relationship

After completing her doctorate in 2013, Swenor did a postdoctoral fellowship at the National Institute on Aging, helping to refine the vision-related elements of the Baltimore Longitudinal Study of Aging, a major project based at MedStar Harbor Hospital in Baltimore. It was during this period that she became interested in what has become one of the central questions of her research today: Does visual impairment directly contribute to dementia and cognitive decline in older adults?

“There are three different pathways that can describe the relationship between vision and cognitive aging,” Swenor says. “First, in some cases, you might have a common factor that causes both visual impairment and dementia. For example, chronic inflammation or cellular senescence might cause visual impairment and concurrently cause problems in the brain. Second, in some cases, changes in the brain, such as neurologic damage, directly cause problems with visual perception. But it’s the third pathway that I’m interested in: When and how can visual impairment lead to a decline in cognition?”

There are several mechanisms through which low vision might gradually harm cognition, Swenor says. “People with visual impairment change their lives. They change their patterns of social interaction. They do less physical activity. They engage in fewer cognitive activities, such as crossword puzzles, and other hobbies.”

All of those behavioral changes are known risk factors for dementia, but as of now, their relative importance in the vision-cognition relationship is poorly understood. The great research challenge of the next 10 years, Swenor says, will be to identify effective interventions that can help patients with low vision reduce their risk of cognitive decline.

In this work, Swenor is building a project parallel to one developed by Frank Lin ’03, professor of otolaryngology–head and neck surgery. Where Swenor focuses on vision, Lin is well-known for his studies of hearing impairment and cognition in older adults. Lin is now directing a large-scale randomized trial exploring whether better treatment of hearing loss can delay the onset of dementia in at-risk elderly adults (see p. 34 for more on Lin’s work). Swenor and Lin have collaborated on a variety of research projects, including studies of elderly adults who are living with both visual and hearing loss.

“Bonnie is phenomenal to work with,” Lin says. “She has great instincts about research design, and she can also draw on her own personal experience of visual impairment. I feel very lucky that I’ve been able to collaborate with her.”

Swenor has recently become intrigued by a second question about vision and cognition: If an older adult has visual or other sensory impairments, what is the best way to measure their dementia in the first place? Many of the standard tests for assessing cognition require a certain baseline of sensory acuity. If a patient scores poorly on those questions, is it because their cognitive processes are failing, or simply because they couldn’t see or hear the question well enough to respond appropriately?

“This speaks to a fundamental question of whether we’re over- or underestimating the overall number of people with dementia,” Swenor says. “Right now, some studies of dementia make certain accommodations for people with sensory impairments, and other studies don’t. There really isn’t a uniform best practice.”

During the next decade, Swenor hopes to work with colleagues to determine the best strategies for accurately measuring actual dementia in people who are visually impaired. If best practices can be identified, she would like the National Institutes of Health and other major funders to promote the use of those practices in all future studies of dementia so that cognitive function can be reliably compared across studies.

Swenor’s work is drawing national attenion, says Heather Whitson, associate professor of ophthalmology at Duke University School of Medicine, who collaborated with Swenor as part of a National Institute on Aging working group on sensory impairment and cognition. “Bonnie is viewed as a leader in demanding attention to outcomes that really matter to seniors dealing with chronic vision impairment.”

Swenor says she never wants her studies to be interpreted as messages of pure gloom. “I often worry that people with low vision might hear about my research and just take away, ‘You’re at greater risk of dementia and frailty and loss of mobility,’” she says. “That’s a pretty grim message. But I hope that the message is actually validating to patients: ‘These effects that you’re feeling from your visual impairment—they’re real. And we’re working on interventions that can improve long-term outcomes.’”

Removing Barriers to Low-Vision Services

Many of those potential interventions fall under the umbrella of “low-vision rehabilitation,” a service that helps visually impaired people live effectively with their disabilities. This field is generally not about eyeglasses or similar devices. Instead, low-vision rehabilitation therapists teach patients to make sensory substitutions (for example, audiobooks or text-to-speech software), help patients redesign their homes and offices for easier navigation, and counsel patients on how to prepare for long-term declines in their eyesight.

Unfortunately, Swenor says, many patients who could benefit from low-vision rehabilitation are never referred to the service. Together with Goldstein, who directs low-vision rehabilitation at Wilmer, Swenor is working on behavior modification strategies that might encourage eye specialists to make those referrals. She and Goldstein have designed a set of pop-up reminders in the electronic record: If a patient has visual acuity below a certain point, their eye doctors will see reminders that recommend referral to low-vision rehab. Those reminders are currently being piloted with 15 physicians at Johns Hopkins.

“Next we’ll look at the other side of the coin,” Swenor says. “Of the patients who have been referred, how many actually come in for services? When they don’t, what are the barriers?”

Goldstein says that one barrier to treatment remains patient finances. Although rehabilitation care with doctors and therapists is reimbursed by Medicare, visual equipment is not. So whatever aids or devices are recommended—text-to-speech software, specialized lenses, lighting—need to be paid by the patient out of pocket. “Often, the people who need these devices most are the people who are least likely to be able to afford them,” Goldstein says.

‘If You Can’t Talk About It, How Can I?’

Swenor disclosed her impairment to West while she was in graduate school, but for a long time, she hid her disability from many colleagues. She did not let others notice when she used text-to-speech tools, and she avoided the topic of why she didn’t drive to campus.

That all began to change roughly a year after she rejoined the university as a faculty member in 2014, after completing her postdoctoral fellowship.

“While I was working on a research study,” she says, “a participant asked to speak to me. They had questions about the study, and in the course of the conversation, it came out that I have this impairment but don’t often disclose or talk about it. And she very pointedly said, ‘Well, if you can’t talk about it, how can I?’ And that was hard to hear.”

Since that time, Swenor has become a vocal advocate for people with disabilities, especially those who work or study at Johns Hopkins.

Swenor herself has recently begun to require an assistant to help her read scientific papers. Text-to-speech software is not much help when visually impaired readers need to digest graphs, charts or figures. In addition, she notes: “When I read a scientific paper, I usually read the abstract, and then I might jump down to the results, and then read the introduction and the methods if I’m interested. I think that’s the way most people read. But text-to-speech software doesn’t allow for any of that. It just kind of barrels through, start to finish. It’s an incredibly inefficient way to take in information.”

Despite the hype around high-tech advances in assistive technology, at this point, Swenor says, human assistance is more efficient for certain tasks for those with vision impairment. In a talk before the American Academy of Ophthalmology in October, she challenged her audience not to be too glibly optimistic about what assistive technologies can currently do. Most smartphone apps and other technologies, she said, don’t yet provide the efficiency and accessibility that people with low vision need. Future technologies, she argued, should not only help patients with low vision perform tasks but ensure that they can perform those tasks efficiently.

Swenor’s department at Wilmer has been able to find funds to support assistance for her. For roughly 10 hours a week, she gets assistance with her visually challenging tasks: proofreading; formatting; summarizing graphs, tables and charts; and dealing with low-contrast online forms.

Swenor says she presses on tirelessly with her research in part because she cannot know how fast her vision will continue to deteriorate.

“My vision has been somewhat stable for over the past year,” she says. “But it’s a degenerative disease. I could wake up tomorrow and my vision could be worse. That used to scare me, but now it just makes me not want to waste time.”