On April 7, 2022, DAI joined the world in observing World Health Day, an annual initiative by the World Health Organization (WHO) to promote good health and well-being of people across the world. We are posting our blog about World Health Day, to coincide with the Seventy-fifth World Health Assembly, being held on 22-28 May 2022 in Geneva.
The theme for World Health Day 2022 focused on raising awareness of the impact of climate change on human health – Our planet, our health.
There is growing research evidence showing that climate change is among the leading global health threat and its impact on health is deeply complex.
One of the environmental health hazards is air pollution which can lead to serious health conditions such as asthma, chronic obstructive pulmonary disease COPD), lung cancer, and the risk of hemorrhagic stroke in older women.
Air pollution is a mix of hazardous gases and fine solid particles and it can come from human-made pollution like, traffic-related air pollution (TRAP) and mother nature pollutants, such as smoke from wildfires, ash and gases from volcanic eruptions. Long-term exposure to these pollutants is associated with oxidative stress and inflammation in human cells and may cause chronic diseases and cancer.
But what about air pollution on brain health?
In recent years, the possibility of air pollution as a significant threat to brain health has caught the attention of neuroscientists and toxicologists. A study done in Ontario, Canada, revealed that adults living within 300 meters to heavy traffic had a higher risk of dementia and the result is consistent with earlier study done on older men who have long-term exposure to air pollution.
The particulate matter (PM2.5) that arises from wildfires and vehicle emission can be inhaled deeply, affecting the central nervous system, and leading to decreased cognition and well-being. Hence, it is not surprising that air pollution was added to the list of 12 potentially modifiable risk factors for dementia by the Lancet Commission on Dementia Prevention, Intervention, and Care in 2020.
Multiple studies have shown that elevated long-term exposure to PM2.5 was associated with higher hazard of all-cause dementia and vascular/mixed dementia. It also aggravated the early decline of episodic memory problems and depressive symptoms in older women as shown in another study.
What this means to prevention, intervention and care of people living with dementia?
It means that air pollution should not be seen just as environmental threat but also a significant threat to human health. Thus, reducing air pollution is everyone’s business just like dementia is everyone’s business.
There is a need to educate public on the connection between poor air quality and cognition decline, and possibility of developing dementia from long-term exposure. More research is needed to determine which kinds of pollutants are most harmful to brain health.
It also means that residential aged care homes should be situated far away from TRAP and industrial pollution since older people are at-risk group.
However, air pollution is not restricted to outdoor but also indoor and in poorly ventilated homes, concentrations of these gases like nitrogen dioxide can be much higher indoors than outdoors.
This is where environmental design can play a significant role in finding innovative ways to improve air quality and reduce indoor air pollution sources. It is about creating a sustainable and livable place and that is one of the environmental focus areas of the DAI Environmental Design Special Interest Group (ED-SiG).
By Emily Ong, DAI Board member and ED-SiG project lead