Our minds and memories define us as individuals. Losing function and control means losing your identity. That’s what makes age-based cognitive decline, especially Alzheimer’s disease, so devastating. No one wants to go through it themselves or watch a loved one turn into a stranger. Luckily, research offers insight into the disease and hope for those at risk. Local experts reveal the latest in prevention and screening.
targeting amyloid-beta
Not much is known about what causes Alzheimer’s disease. Genetics and age are confirmed factors, but less is known about other elements that may put you at risk. Dr. John Morris, an Alzheimer’s specialist at Washington University School of Medicine, explains that evidence suggests a key process that triggers the disease is the alteration of a brain protein called amyloid-beta. Pieces of the protein clump together to form plaques, and it’s believed that the plaques may block cell-to-cell signaling at synapses, as well as have other negative impacts. “This alteration by itself is insufficient to produce the clinical manifestations of Alzheimer’s, mainly dementia,” Morris explains. “There are many other lesions and abnormalities that go on in the brain after amyloid changes begin.” These multiple changes are likely critical to producing dementia, he notes.
The combination of changes in the brain means that treatment for Alzheimer’s needs to target multiple pathologies, Morris says. But prior to signs of memory loss, an anti-amyloid drug may be all that’s needed for effective intervention. “We now can detect amyloid beta in people who do not have dementia yet,” he says. “It’s the initial phase of brain change, and it’s possible that addressing the amyloid alteration early might stop the other changes from happening and prevent the onset of dementia.”
There are currently two ways to test for amyloid beta plaques, according to Morris. The first is a positron emission tomography (PET) scan, a sophisticated brain imaging procedure. He say the PET scan uses a radioactive substance called a tracer to show changes in the brain, including amyloid alteration. Morris says the second method is a spinal tap, which analyzes a sample of cerebrospinal fluid. Unfortunately, these procedures can be expensive and invasive. Morris says there are efforts to create a test that measures amyloid-beta in the blood. “The amount is infinitesimal and overwhelmed by the concentration of other proteins, which makes detection much more difficult,” he says. “But just because it hasn’t been successful yet doesn’t mean it won’t be.”
lifestyle changes
The uncertainty surrounding Alzheimer’s can make the situation seem hopeless. SLUCare geriatric psychiatrist Dr. George Grossberg wants patients to know that is not the case. He notes that there are a variety of factors related to the disease, and while some, like genetics and age, cannot be modified, many can be controlled.
Grossman says evidence of the effectiveness of certain lifestyle interventions has been shown in the Finnish Geriatric Study to Prevent Cognitive Impairment and Disability (FINGER). The study followed 1,200 people at risk for cognitive decline. The control group received normal health advice, but the rest participated in the four areas of intervention. “The study saw clinically significant improvement in those who employed the interventions,” Grossberg says. “Just one of the modifications can have an impact, and it’s magnified when you combine them all.” He notes that the Alzheimer’s Association announced its own lifestyle intervention study. “It’s exciting to explore solutions that aren’t pharmaceutical,” he says. “There is no downside to making these changes. It’s good for everyone.”
There are four areas of lifestyle modification that can help lower or delay your risk for developing Alzheimer’s:
- nutritional counseling: “We know there are certain healthy diets that decrease the risk for Alzheimer’s disease,” Grossberg says. Research shows a Mediterranean diet—fish, vegetables, fruits, olive oil, red wine, and not much red meat or processed foods—is effective.
- physical activity: Grossberg says there is growing evidence that daily walking or some other sort of exercise is good for the brain. “I advise families not to be couch potatoes,” he says. “Don’t make the remote your best friend.”
- cognitive and social activity: Exercising your brain and being social also lowers your risk or can delay the onset of the disease. Grossberg recommends that people continue to read, do puzzles, play cards and engage with others.
- cardiac health: “What’s good for the heart is good for the brain,” Grossberg says. Getting cardiovascular risk factors like high blood pressure, cholesterol and diabetes under control can have big benefits you might not have considered. The same goes for avoiding risk factors like smoking, he notes.
screening
There is no one test for Alzheimer’s, explains Cheryl Kinney, senior director of client services for the Alzheimer’s Association, Greater Missouri Chapter. “We want people to notify their doctors if they notice changes in memory or information processing for themselves or a loved one,” she says. But memory screeners on their own cannot provide an Alzheimer’s diagnosis. She notes that thyroid problems, drug reactions, tumors, strokes and hydrocephalus (a condition where cerebrospinal fluid accumulates within the brain) can cause similar symptoms. “By looking at your medical history, testing your mental status, and performing neurological exams and blood tests, your doctor can determine the cause of dementia,” she says.
Kinney says early diagnosis is important. “It helps people understand their options and begin treatment; they may even be eligible for a clinical trial to test new treatments,” she explains. “It also gives them more time to plan for their future. They can get their legal and financial affairs in order before the burden completely falls on their family.”
Medicaid pays for cognitive and depression screening for eligible individuals. Grossberg points out that 65 is still young for symptoms to manifest, and screenings tend to be more effective in 70- to 75-year-olds. But like Kinney, he and Morris suggest people inform their doctor as soon as they notice memory changes.
10 warning signs and symptoms for alzheimer’s
- Memory loss that disrupts daily life
- Challenges in planning or solving problem
- Difficulty completing familiar tasks at home, at work or at leisur
- Confusion with time or place
- Trouble understanding visual images and spatial relationships
- New problems with words when speaking or writing
- Misplacing things and losing the ability to retrace step
- Decrease in/poor judgement
- Withdrawal from work or social activities
- Changes in mood and personality
Source: Alzheimer’s Association
ApoE and the tsimane project
Apolipoprotein E (ApoE) helps mediate cholesterol metabolism and transport fatty acids to the brain. However, some variations of the protein, especially ApoE4, are indicators of increased risk for Alzheimer’s disease. Dr. Ben Trumble of Arizona State University has been studying the function of ApoE as part of The Tsimane Health and Life History Project, which studies the Tsimane people, an indigenous population in Bolivia with a forager-farmer society. The project combines anthropological and biomedical research to better understand how the human life cycle has evolved.
When testing the cognitive function of the Tsimane, Trumble found that some ApoE4 carriers had higher mental function, but only in individuals who had been exposed to parasites. Such exposure is much more common in the remote, tropical Bolivian lowlands than industrialized, urban environments. Trumble theorizes this means ApoE4 may have played a role in maintaining mental acuity when humans lived primarily as hunter-gathers and were more exposed to environmental-based health threats.
Sources: Arizona State University, National Institute on Aging
