New research estimates that hundreds of thousands of dementia cases in the United States may be caused by the air we breathe.
As people live longer, an increasing number of nations are battling rising dementia rates. Each year, nearly 188,000 cases of dementia are attributed to air pollution in the United States, with poor air quality due to wildfires and agriculture demonstrating the strongest association with an increased risk of Alzheimer’s disease and other forms of dementia in later life.
The research, which was published in the journal JAMA Network Open on Monday, August 14, contains new estimates that highlight a variety of health hazards long associated with air pollution.
Studies have already established a link between poor air quality and a variety of health issues, including the risk of developing dementia. However, the new study examined how specific causes of air pollution appear to be linked to dementia more strongly than others.
The findings were based on an analysis of data accumulated over decades for a National Institutes of Health-supported survey. Every two years, thousands of older individuals were examined regarding their health.
The researchers then combined this information with detailed air quality modeling to estimate the potential exposure of individuals in their living areas. The focus was on what scientists refer to as PM 2.5 air pollution, which is a standard for very small particles (less than 2.5 micrometers broad, a fraction of the width of a human hair) that can be inhaled.
These particles can originate from a variety of sources, including vehicle emissions and ash from wildfires. They are associated with a variety of adverse health effects, ranging from coughing and shortness of breath to asthma exacerbation and an increased risk of mortality from heart disease.
Sources of Air Quality Information and Factors Affecting Results Including Wildfires and Agriculture Emissions
Various data sources were consulted, including measurements from the Environmental Protection Agency and information about nearby factors that could influence air quality – such as the recent wildfires in Canada, which prompted air quality alerts in major US cities.
Even after adjusting for a variety of potential other factors that could influence results, such as gender, race and ethnicity, educational status, and affluence, modeling revealed a higher risk. They were also able to account for whether a person’s previous residence was urban or rural.
Dr. Adar acknowledges that while they had information about where people moved during the course of the survey, they did not have enough data to model every exposure or check for every disparity throughout their life, such as where people were born, which could have affected the results.
Beyond direct emissions from wildfires and agriculture, Dr. Adar explained that their analysis could also account for other types of air pollution that can be traced back to these sources.
Other toxic molecules can be transported through communities by the smoke as it burns. Due to the ammonia emitted by sources such as manure and fertilizer, farming can also exacerbate air pollution.
Source: Mirror News