But “the brain and its relationship to dementia is a relatively recent topic,” said the lead study author Mark Weiskopf, Cecil K. and Philip Drinker Professor of Environmental Epidemiology and Physiology at the Harvard TH Chan School of Public Health. “Dementia is a huge problem worldwide. If we can reduce exposure to these particles, we can reduce the burden of dementia.”
more 57 million people Worldwide there are people living with dementia, a number expected to increase to an estimated 153 million by 2050.
A meta-analysis published Wednesday in the British Medical Journal (BMJ) examined 16 observational studies and found consistent evidence of a link between PM 2.5 and dementia, even when a person’s annual exposure was less than 12 micrograms per cubic meter of air, the current Environmental Protection Agency standard, the study found. It has been said. A grain of rice weighs about 30,000 micrograms, Weiskopf said.
Studies have measured dementia subjects’ overall exposure to the pollutant from one year to 20 years, although “it’s unlikely that dementia-causing exposure is actually as little as one year, but researchers use that number as a surrogate to estimate long-term exposure,” Weiskopf said.
EPA is considering strengthening air quality standards Lower PM 2.5 exposure Between nine and 10 micrograms per year, or between eight and 11 micrograms per cubic meter of air. The agency sought public comment on both measures.
According to the World Health Organization, ninety-nine percent of the world’s population is exposed to levels of PM 2.5 considered unhealthy—annual concentrations greater than five micrograms per cubic meter. Study Published last month.
Increased PM 2.5 exposure is associated with increased dementia risk
Harvard scientists examined studies that used a method known as “active case ascertainment,” a process in which each participant is screened in an extensive effort to confirm a dementia diagnosis, Weiskopf said. This approach is more accurate than “passive case containment,” which involves random screening and “can miss a lot of cases,” Weiskopf said.
They used more precise software tools to eliminate biases that could affect the results, such as disparities in health-care access and the amount of pollutant exposure, Weiskopf said.
They found a 17 percent increase in the risk of dementia for every two-microgram increase in air per cubic meter of annual PM 2.5 exposure, as well as a smaller increase in the risk of breathing nitrogen oxides and nitrogen dioxide, pollutants that often result from traffic exhaust.
It’s not clear how air pollution affects the development of dementia, said Rebecca Edelmayer, senior director of scientific engagement at the Alzheimer’s Association, but “it’s hypothesized that very small particles of pollutants enter our bodies and enter our circulatory system, which supplies fuel to the brain.”
Some scientists speculate that it may be related to chronic inflammation in the body, or Buildup of beta amyloid levels Blood is often present in the brain of Alzheimer’s disease patients Abnormal levels of beta amyloid which together form plaques that disrupt neuron and cell function.
“These data illustrate that there are many factors across the lifestyle that can contribute to our risk of dementia, including the environment,” Edelmayer said.
PM 2.5 pollutants often come from construction sites, unpaved roads, smoke and fires, or complex chemical reactions with pollutants emitted from power plants, industrial facilities, cars and trucks.
“Most people don’t have the power to control or influence the quality of the air they breathe in their environment, so it’s not a personal risk they can manage themselves,” said Christina custom, clinical director of the Institute for Brain Health and Dementia at George Washington University who was not involved in the study. “For most people, a diagnosis of dementia is something they dread because – beyond living with it as well as they can – there’s not much we can do to reverse it. So any work that allows us to identify risk factors and prevent people from developing dementia is something we need to focus on.”
Furthermore, these pollutants disproportionately affect vulnerable populations such as children, the elderly, and those with existing heart or lung disease, as well as low-income neighborhoods and communities of color, where polluting industries are frequently located. “The story of dementia and discrimination and race is very real,” Prather said.
American Lung Association, among others 2022 “State of the Air” Reportfound that more than 4 in 10 Americans live in areas with unhealthy air quality.
Dementia is among the many health problems linked to air pollution
Recent studies have added dementia to the numerous dangers of air pollution documented by a growing body of scientific research in recent years.
Many studies – including its June 2022 report Health Effects Institute — linked air pollution to health problems viz Heart disease and strokeLow birth weight, circulatory problems, lung cancer mortality, worsening asthma, Especially in children, Diabetes, cognitive decline And birth defectAnd premature death.
Research Also linked to social effects such as air pollution exposure Substance abuse, self harm, suicide And crime.
This pollution pollutes the air and heats the planet, underscoring the dangers of climate change, experts say.
“This meta-analysis reinforces my belief that ending the use of fossil fuels is the single most important intervention we can take to protect human health,” said Gaurav Basu, a physician and health equity fellow at the Center for Climate, Health and the Global Environment at the Harvard TH Chan School of Public Health who was not involved in the research. “This study helps us bring cognitive health to the fore in the conversation about the benefits we get from a rapid transition to a clean energy economy.”
Basu said that as a primary care physician, he regularly sees “the tragic impact of dementia” on his patients and their loved ones.
Many people are exposed to air pollution, and reducing their exposure could make a huge difference in the overall global burden of dementia, now and in the future, with substantial population-level health implications, Weiskopf said.
“Dementia has a tremendous personal, health, social and financial cost to the world, so anything we can do to delay, modify or prevent it can have a huge societal impact,” he said.
