Cancer survivors who got radiation treatments as children have nearly twice the risk of developing diabetes as adults. Thatâ€™s according to a study led by Emory and Childrenâ€™s Healthcare of Atlanta pediatric oncologist Lillian R. Meacham, MD.
Lillian Meacham, MD
The study, published in the August 10/24 issue of Archives of Internal Medicine, compared rates of diabetes in nearly 8,600 childhood cancer survivors diagnosed between 1970 and 1986, and nearly 3,000 of their siblings who did not have cancer.
Children who were treated with total body radiation or abdominal radiation to fight off cancer appear to have higher diabetes risks later in life, regardless of whether they exercise regularly or maintain a normal weight.
After adjusting for other risk factors, including body mass index – a ratio of height and weight – Meacham and team found that childhood cancer survivors overall were 1.8 times more likely to have diabetes.
And the more radiation that was used, the greater the diabetes risk. For those treated with total body radiation — a treatment often used before bone marrow transplants to treat childhood leukemia — the diabetes risk was more than seven times greater.
More study is needed to understand how radiation could promote diabetes in cancer survivors, notes Meacham.
She says it is imperative that clinicians recognize this risk, screen for diabetes and pre-diabetes when appropriate, and approach survivors with aggressive risk-reducing strategies.
Meacham is a professor of pediatrics in the Emory School of Medicine and medical director of the Cancer Survivor Program with the AFLAC Cancer Center and Blood Disorders Services, Childrenâ€™s Healthcare of Atlanta.
Susan Primo, MD
The patients seen by Emory low vision specialist Susan Primo, OD, MPH, have already exhausted most of their treatment options. They’ve completed medication regimens or had surgery to slow advanced age-related macular degeneration (AMD), a leading cause of blindness in the elderly. But still they don’t see well.
That’s where Primo comes in. At the Emory Eye Center, sheâ€™s studying whether behavioral modifications can lead to a change in brain activity to maximize use of remaining vision.
In macular degeneration, the maculaâ€”a layer of tissue on the inside back wall of the eyeballâ€”gradually deteriorates. That delicate tissue is responsible for visual acuity, particularly in the center of the retina. Central vision is needed for seeing small and vivid details such as words on a page or the color of a traffic light, which means it is vital for common daily tasks such as reading or driving.
In more than two decades of working with patients who are visually impaired, Primo realized that people typically use their peripheral vision to compensate for loss in central vision. Studies have shown that people with progressive central vision loss compensate by spontaneously adopting a preferred retinal location (PRL) that takes over responsibility for visual clarity.
But Primo and Georgia Tech psychologist Eric Schumacher wanted to know whether using these peripheral regions causes a change in how the brain is organized. Armed with Schumacher’s expertise in functional magnetic resonance imaging (fMRI) and Primo’s clinical experience, the researchers did indeed discover continued activity in the part of the brain that maps to the macula. The brain scans of people with AMD who had developed their peripheral vision showed substantially more activity than those of people who had not developed a PRL. Their study appeared in the December 2008 edition of Restorative Neurology and Neuroscience.
In a current study, Primo and Schumacher are exploring whether occupational training and biofeedback can help people with AMD focus on using good retinal cells and in turn speed up the brain’s reorganization.
“Although others have tried to study this reorganization of macular degeneration before, no one, to our knowledge, has tried to influence it,” says Primo. “Yet it’s important to begin to come up with therapies, treatments, and technology to help patients begin to use their residual vision faster and better than they could before.â€