Local researchers are studying a toxic protein found in the brain of Alzheimer’s patients to see what can be done to better treat and slow the progression of the disease.
Alzheimer’s disease, the most common form of dementia, causes problems with memory, thinking and behavior that gradually get worse over time. One in nine Americans 65 and older suffer from the disease, which affects about 5.2 million in the U.S., according to the Alzheimer’s Association.
The greatest risk is related to age, said Mark Todd, a neuropsychologist with Cleveland Clinic Florida in Weston. The risk also increases as you get older. Nearly a third of those 85 and older have the disease, according to the Alzheimer’s Association.
“Having a parent or sibling who has dementia increases risk by three or four times,” Todd said. Medical conditions like diabetes, hypertension and sleep apnea also increase risk, especially if the conditions are untreated.
Don’t smoke, limit alcohol use and increase physical activity, Todd said. Research shows that moderate exercise, three times a week or more for at least 20 minutes of elevating your heart rate, helps reduce the accumulation of amyloid protein in the brain, he said. “If you are older and can’t get around, you don’t have to run a marathon, but you can sit in a chair and learn aerobic exercises using your arms and legs to get to your target heart rate.”
The Mediterranean diet, with fish, green leafy vegetables, nuts and fruit, is helpful, as well as a low-fat diet, green tea, and chocolate in moderation. Staying cognitively active, by learning a new language, taking a class, doing puzzles and games also helps improve mood and avoid depression. People over 65 who are depressed or have anxiety are more likely to develop a cognitive disorder, he said.
“But watching TV doesn’t help, even if it’s the History Channel,” Todd said. “I’d rather them go to a history class at a local university and talk with other people to make themselves think, more than just having the information passively given to them through the TV.”
Local researchers are studying amyloid to determine how things like imaging, stem cells and boosting the body’s immune system can help mental decline and better target treatment options. A form of amyloid called beta-amyloid clumps together into “plaques” that are toxic to nerve cells in the brain. These plaques are one of the indicators of Alzheimer’s.
A study at Mount Sinai Medical Center in Miami Beach is investigating the impact an amyloid PET scan, which images amyloid plaques in the brain, has on the treatment of people with cognitive impairment whose diagnosis is unclear. “The purpose of the study is to determine if the imaging makes a difference in the management of the patient,” said Dr. Ranjan Duara, medical director of the Wein Center for Alzheimer’s Disease and Memory Disorders at Mount Sinai.
The amyloid PET scan, which is available commercially for about $4,500, is not covered by insurance. Researchers hope to provide evidence with the study to support reimbursement by Medicare and private insurers.
“They want to know whether getting this PET scan early on will save them money by determining the diagnosis quickly and determining which treatment is best for the patient,” Duara said.
The study is enrolling more than 18,000 Medicare beneficiaries ages 65 and older from around the country. Mount Sinai is recruiting for the study, which will continue for about four years. Eligible patients should have mild cognitive impairment or dementia with an uncertain cause, and must be evaluated by a specialist who thinks the scan would be helpful in the diagnosis.
Miami Jewish Health Systems
There are 18 actively enrolling clinical trials related to Alzheimer’s at Miami Jewish Health Systems in northeast Miami. Three are using immunotherapy to treat Alzheimer’s. “They are primarily done with regular intravenous infusions of antibodies,” said Dr. Marc Agronin, vice president for behavioral health and clinical research at Miami Jewish Health Systems. “Immunotherapy tries to get our own immune system to recognize and get rid of the toxic protein beta-amyloid.”
The studies are enrolling individuals with mild to moderate Alzheimer’s, generally ages 50 to 90, who are in good physical health and who can have regular brain scans, both MRIs and PET scans, he said.
“We are excited about these trials, because to date they have the most preliminary data that points to the ability to slow down the course of Alzheimer’s,” said Agronin, author of How We Age: A Doctor’s Journey into the Heart of Growing Old. “Preliminary data shows that for mild Alzheimer’s disease, it may slow it down as much as 34 percent.”
To qualify, patients have to have a PET scan to show the amyloid protein is in the brain.
“It’s a new frontier of treatment. If we can demonstrate that this treatment can slow it down, the importance is to implement it much earlier in the course of the disease,” Agronin said. “It’s like putting out a fire. The earlier you get to it, the more effective your methods.”
University of Miami
A University of Miami study is the first clinical trial in the U.S. to examine the effect of stem cells on Alzheimer’s disease. “We’re trying to decide if stem cells can reduce the rate of decline or even improve the symptoms,” said Dr. Bernard Baumel, assistant professor of neurology at UHealth — the University of Miami Health System. “Stem cells have anti-inflammatory properties and may affect the amyloid protein.”
The brain is always producing and reducing amyloid, he said. In Alzheimer’s patients, amyloid is made in a quantity that is not reduced normally by the brain, and around these amyloid plaques you get inflammatory cells that are very destructive. “If you can reduce inflammation, you can quiet the brain and hopefully allow the normal reduction of amyloid to happen,” Baumel added.
The stem cells, taken from the bone marrow of healthy donors, also help the production of new cells. “So the hope is that it will reduce destruction caused by inflammation, and even hopefully replace cells that have died in the part of the brain that causes Alzheimer’s,” he said.
Stem cells are tolerated well by recipients, and there is a long history of using stem cells in other conditions, such as to repair damage to the heart in cardiac patients, for joint diseases, and now to see if they repair the lungs in patients with severe lung disease. “It’s time now that we see how it works in central nervous system problems like Alzheimer’s,” Baumel said.
The study is open to 30 people with mild Alzheimer’s, ages 55-80, who are otherwise healthy. The stem cells will be infused intravenously. For information, call 305-243-6633 or emailMemoryProgram@med.miami.edu.