Study stresses stress test in treating patients with AMD

Might something borrowed help doctors of optometry care for patients feeling stressed out because of age-related macular degeneration (AMD)?

Researchers at The Ohio State University (OSU) College of Optometry and the OSU Department of Ophthalmology are exploring just that possibility—using the Perceived Stress Scale (PSS). Designed in the 1980s for people to self-report the degree of stress they feel in their lives, the psychological survey might provide insights into interventions for patients with AMD and also whether stress might contribute to AMD, researchers say.  

Their research appeared in the March 2017 issue of Optometry and Vision Science. The study tested nine of the PSS' 14 questions—based on their relevance—among 137 patients with a diagnosis of AMD. Their average age was 82.  

The Perceived Stress Scale showed "acceptable measurement properties" and could be useful in assessing the perceived stress in patients with AMD, they concluded in the research.  

"It's very important to remember to consider the potential psychological consequences of vision loss," says the study's lead author Bradley Dougherty, O.D., Ph.D. "By identifying stress in patients with AMD, a doctor of optometry may be able to refer the patient for valuable treatment, in addition to what might be considered traditional optometric care. We are currently investigating whether the inflammation that can result from stress may also negatively affect AMD treatment outcomes."  

"Eye care professionals do not routinely test for stress during a comprehensive eye examination, which is why research on identifying and quantifying perceived stress is important," says study co-author San-San Cooley, O.D., an OSU College of Optometry assistant professor.  

According to the Centers for Disease Control and Prevention, AMD is the leading cause of vision loss in this country among people 65 years and older. Previous studies have linked depression and AMD, but rarely have they explored the connection between stress and AMD, the study's authors say.  

AMD and quality of life   

AMD can result in a number of stresses for patients. And it's not unusual for a doctor of optometry to refer a patient to a health care provider who can help AMD patients with depression.

"The relationship between stress and AMD is not fully understood, and it depends on what other chronic conditions are being considered," says Dr. Dougherty, an assistant professor at the OSU College of Optometry. "However, one can easily think of a number of potential sources of stress for a person with AMD. These patients are facing the prospect of uncertain visual outcomes and severe, permanent vision loss. They also often experience rapid declines in vision, which can have serious negative consequences for their daily lives."  

Dr. Cooley adds, "Some of the consequences of AMD might include loss of driving privileges and subsequently independence, inability to read and manage daily tasks like paying bills, and difficulty recognizing faces. Additionally, the treatment that many people with exudative AMD receive (intraocular injections) can itself be a source of stress."  

Read more about AMD in the AOA's clinical practice guideline, Care of the Patient with Age-Related Macular Degeneration. Doctors also can refer their patients with vision loss and depression, anxiety or stress to a health care provider who cares for patients under emotional distress. Also, based on the AOA clinical practice guideline, Care of the Patient with Visual Impairment (Low Vision Rehabilitation), doctors can provide or refer patients with functional vision problems to an eye doctor who can perform a comprehensive low-vision examination. 

A 1998 study, "The Pyschosocial Impact of Macular Degeneration," noted that quality of life and emotional distress in AMD patients was "significantly worse" than for people with chronic illnesses such as arthritis, chronic pulmonary disease and bone marrow transplants.  

'Complete care'   

The well-regarded PSS scale was developed by psychologist Sheldon Cohen, the Robert E. Doherty University Professor of Psychology at Carnegie Mellon University. The scale is typically used by psychologists. But it also has been used by epidemiologists in studies, psychoneuroimmunologists, endocrinologists, some physicians and public health care providers, according to Cohen. Says Dr. Cooley: "A first step that a doctor could take is using a survey such as the PSS to formally evaluate perceived stress levels. From there, doctors could familiarize themselves with local mental health providers and with other strategies that could be effective for patients to manage their own stress."

"Understanding a patient's level of perceived stress could help identify those who would benefit from interventions for managing stress," Dr. Dougherty says. "While it may not be commonly considered, as it's not directly related to the eye, the identification and management of perceived stress should be thought of as important to the complete care of the patient."