Dementia and Modifiable Risk Factors: Latest Study Adds Air Pollution to a Long List

As one gets older, it is common to experience some cognitive decline with typical brain aging, such as subtle changes in memory, thinking, and  reasoning, explains the U.S. Centers for Disease Control and Prevention (CDC). However, dementia is not an inevitable part of typical brain aging, the CDC adds.

That leads to another important point about dementia and Alzheimer’s, which is the most common form of the disease: There are several modifiable risk factors that seem to be mounting as new clinical studies emerge.

The most recent study found that exposure to traffic-related air pollution was more likely to produce high amounts of amyloid plaques associated with Alzheimer’s in the brain. Published in Neurology, the medical journal of the American Academy of Neurology, the study does not prove that air pollution causes more amyloid plaques in the brain – but it found an association.

However, it is not the first study to find such an association, explains G. Peter Gliebus, M.D., a neurologist with a subspecialty certification in behavioral neurology and neuropsychiatry, at Marcus Neuroscience Institute, part of Baptist Health, at Boca Raton Regional Hospital. A 2017 study found that people living in closer proximity to major roads have a slightly higher risk of developing dementia.

G. Peter Gliebus, M.D., neurologist at Marcus Neuroscience Institute, part of Baptist Health, at Boca Raton Regional Hospital.>

“This new study has revealed a matter of concern -- individuals living in areas with higher air traffic pollution may have a greater risk of developing Alzheimer's disease pathology, as demonstrated during autopsies,” said Dr. Gliebus. “It is important to note, however, that the study only establishes a correlation and not a causation. Nevertheless, it is worth mentioning that this is not the first research to suggest a relationship between air pollution and cognitive decline, particularly Alzheimer's disease.”

Dementia is a general term that may include loss of memory, language, problem-solving or other thinking abilities that are severe enough to interfere with daily life. A recent CDC study examined how common eight risk factors  were among adults 45 years and older. The risk factors considered were hypertension (high blood pressure), not getting enough physical exercise, obesity, diabetes, depression, smoking, hearing loss, and binge drinking.

The CDC study’s results were striking: Nearly 50 percent had high blood pressure or did not meet the aerobic physical activity guideline. Adults with cognitive decline were more likely to report at least 4 factors (34 percent) than those without cognitive decline (13 percent).

“These risk factors can have a significant impact on an individual's health and the risk of developing cognitive decline, but among them, hypertension and physical inactivity are the most common,” explains Dr. Gliebus. “High blood pressure, or hypertension, is linked to an increased risk of developing dementia and cardiovascular diseases and can have severe consequences on one's health. Similarly, physical inactivity is a major risk factor that can significantly affect brain health and overall well-being, making it crucial to maintain a regular exercise routine.”

With the growing elderly population, cases of dementia and Alzheimer's are expected to continue rise. Dr Gliebus acknowledges the challenges of dealing with a family member who is struggling with memory loss or showing early signs of cognitive decline.

“It's important to approach the situation with kindness, empathy, and understanding,” he said. “Both the person experiencing dementia or Alzheimer's and their caregivers face challenges that require patience, compassion, and an attentive ear.”

Additionally, early diagnosis is crucial in managing dementia and Alzheimer's.

“If you observe any memory loss symptoms in your loved one, it's wise to talk to a doctor as soon as possible,” said Dr. Gliebus. “Early treatment can help manage symptoms and improve the quality of life for those affected. It's also  essential to look for resources and support groups available for people with dementia and their families. Connecting with others who are going through a similar situation can provide emotional support and practical advice.”