According to the Centers of Disease Control and Prevention (CDC), age-related macular degeneration (AMD) is the leading cause of permanent impairment of reading and fine or close-up vision in the US for people aged 65 and over.
1.8 million people aged 40 and over are currently affected by the condition in the US, and another 7.3 million are believed to be at risk of developing AMD. It is predicted that the amount of people who have developed AMD will reach 2.95 million by 2020.
A previous study published in JAMA Opthalmol. has reported that there is a significant association between vision loss and depression, but now new research has found that a form of rehabilitation therapy can reduce this risk in people with AMD by half.
The new study tested an approach called "behavior activation." According to study co-author Robin Casten, PhD, associate professor of psychiatry and human behavior at Thomas Jefferson University, Philadelphia, behavior activation is a method that involves helping people to recognize that the loss of enjoyed activities could lead to depression, and then helping them re-engage with those activities.
The research was funded by the National Eye Institute (NEI) and published in Opthalmology.
AMD occurs when the macula - the most sensitive part of the retina and responsible for clear vision in your direct line of sight - becomes damaged over time. The condition commonly results in a blurred area in the center of a person's vision
Age-related macular degeneration is most likely to affect people over 60 years of age.
Although it does not in itself lead to blindness, the central vision loss can severely impair simple day-to-day activities such as reading, writing and driving. What may once have been enjoyable and fulfilling activities can become a struggle to complete. It can become very difficult to leave home and navigate unfamiliar places, and subsequently social life can suffer.
Dr. Barry Rovner, professor of psychiatry and neurology at Sidney Kimmel Medical College, Thomas Jefferson University, states that as the depression is a response to disability, they reasoned "an effective treatment would be to reduce the disability through rehabilitation."
For the study, the researchers recruited 188 people with bilateral AMD from an ophthalmology practice in Philadelphia. The participants had an average age of 84 years, 50% lived on their own and 70% were female. All had the same level of visual impairment, mild depressive symptoms and were at risk of developing clinical depression.
All participants had two appointments with an optometrist who prescribed low-vision devices to aid them, such as handheld magnifiers. Following these appointments, the participants were then split into two groups; one group would receive behavior activation therapy from a specially trained occupational therapist while the other group served as a control group, not receiving any occupational therapy.
The occupational therapist worked with the participants in the first group to help them use low-vision devices, make practical changes to their home, increase their social activities and give them structure through the setting of personal goals.
Depression risk reduced
After 4 months, 19 participants had either passed away or withdrawn from the trial: 12 from the control group and seven from the group receiving therapy. Out of the remaining participants, 23.4% of the control group and 12.6% of the group receiving behavior activation therapy developed clinical depression.
The researchers calculated that behavior activation reduced the risk of depression by 50% compared with the control treatment.
Eleanor Schron, PhD, group leader for clinical applications at NEI, said that the study helped to tackle an important issue in eye care:
"AMD is typically diagnosed and treated in primary eye care settings, where there is no defined standard of care for depression. This study was a unique and compelling effort to address that issue by strengthening teamwork between eye care professionals and mental health professionals."
The researchers are continuing to follow the participants of the study in order to see if these recorded benefits are maintained for one year.
Dr. Rovner identifies that for behavior activation therapy to be more available for AMD patients, stronger links would need to be made between primary eye care and mental health care workers, and specialized instruction would also be needed for occupational therapists.
Although the study is limited by the size and location of its sample of participants, it could serve as a starting point for similar approaches to preventing and treating depression in people with AMD.
Written by James McIntosh