Averting Alzheimer’s through exercise, clean air and an active social calendar

November is Alzheimer’s Awareness Month, and USC scientists are researching healthy lifestyle choices and certain drugs that might reduce the risk of developing the disease.

November 21, 2019 Leigh Hopper

November is Alzheimer’s Awareness Month, and scientists at USC are researching measures that might reduce the risk of developing the disease. Experts are examining the role of fine particle pollution, the positive impact of healthy lifestyle choices and testing drugs to prevent disease in at-risk individuals who aren’t showing any symptoms.

Reducing risk for memory loss and Alzheimer’s disease

“We do not yet know how to prevent or cure Alzheimer’s disease, although we know that genetics, lifestyle, and environmental exposures all contribute,” said Margaret Gatz, an expert on aging and Alzheimer’s disease and professor of psychology, gerontology and preventive medicine at the USC Dornsife College of Letters, Arts and Sciences. “Nonetheless, there are things that can be done to reduce people’s risk – regular physical exercise, controlling blood pressure and diabetes, and keeping one’s brain active and engaged.”

Gatz is studying twin pairs where one member of the pair has developed Alzheimer’s disease while the other has not, to better understand risk factors to which the affected twin was uniquely exposed and protective factors in the life of the unaffected twin.

Could a drug started before problems arise prevent Alzheimer’s?

Paul Aisen, a professor of neurology and director of the Alzheimer’s Therapeutic Research Institute at the Keck School of Medicine of USC, said a true Alzheimer’s prevention trial would be difficult to do because it would require thousands of healthy, asymptomatic participants followed for many years to compare the rate of occurrence of Alzheimer’s in individuals treated with a drug or placebo.

But the next best thing, he said, is currently underway: “It’s a very early treatment trial, sometimes called a ‘secondary prevention trial,’ that enrolls individuals who have evidence amyloid in the brain but no Alzheimer’s symptoms and tracks the rate of subtle cognitive decline across treatment arms. This is the design of the A4 trial now in progress.”

Aisen is one of the organizers of the upcoming Clinical Trials on Alzheimer’s Disease scientific meeting, taking place Dec. 4-7 in San Diego, where he will deliver a keynote address titled “Failure after failure, what’s next in AD drug development?”

Ruling out other conditions

Tatyana Gurvich, a certified geriatric pharmacist and an assistant professor at the USC School of Pharmacy, looks at Alzheimer’s a little differently; she’s interested in figuring out the problems that may mimic Alzheimer’s.

“Before diagnosing Alzheimer’s disease, it is very important to rule out other conditions,” she said. “Sometimes depression, anxiety, insomnia, poor thyroid function or a simple vitamin deficiency can contribute to worsening memory and confusion. Fixing those problems will lead to improved memory.”

A careful review of a patient’s current medication list — including all prescriptions, over-the-counter medicines, herbs, supplements, cannabis and alcohol — is necessary before diagnosing Alzheimer’s.

“Many of these substances can contribute to confusion and memory impairment. Once they are removed, memory may improve,” she said.

Does dirty air play a role?

Andrew Petkus, an assistant professor of clinical neurology at the Keck School of Medicine, is interested in the role that fine particle pollution may play in Alzheimer’s. Fine particles, also called PM2.5 particles, come from traffic exhaust, smoke, dust and other sources, and can reach the brain when inhaled.

A number of studies have shown that individuals who are exposed to higher levels of pollutants are at higher risk for Alzheimer’s disease.

“I think it’s important to study because we can identify some physical mechanisms that might be causing some of the physical changes in the brain,” he said. “It’s important to help us understand that process so we can identify targets for eventual treatments.”

Social activities keep the brain at its best

Of the 5.8 million Americans living with Alzheimer’s disease, nearly two-thirds are women. The reason for this striking discrepancy isn’t yet known, and proposed theories range from differences in hormones to lifestyle factors.

Carolyn Kaloostian, an assistant professor of clinical family medicine at the Keck School of Medicine with expertise in catching the early signs of the disease, believes an active social life is key to keeping healthy.

“Family members and primary care physicians should encourage more women to participate in activities that are good for their cognitive health. Research has increasingly shown that leading an active social life can protect from memory loss,” she said. “When we are working, our social circle and cognitive work is chosen for us. Later, women must seek out social engagement in their communities. These stimulating activities can help keep our brain at its best.”

alzheimer's research funding
USC’s federal funding for its research on Alzheimer‘s and related dementias increased by more than 400% between 2015 and 2018. That figure includes large grants for clinical trial infrastructure as well as a drug trial to prevent Alzheimer’s in people with “preclinical” disease. (USC Illustration/Diana Molleda)