Environmental pollution linked to depression and heart failure

Research on pollution, depression and the heart, which has just been presented at ESC Preventive Cardiology 2024, the scientific congress of the European Society of Cardiology (ESC), shows that “the air we breathe affects our mental well-being, which in turn turn affects heart health,” said the study’s lead author, Dr. Shady Abohashem of Harvard Medical School in Boston.

Air pollution was responsible for an estimated 4.2 million premature deaths worldwide in 2019, according to the World Health Organization. Mental illness is also associated with premature death. This study examined whether air pollution and poor mental health are interrelated and have a joint effect on mortality from cardiovascular disease.

Studying

The study focused on particles smaller than 2.5 micrometers in diameter, also known as fine particulate matter or PM2.5. They come from vehicle emissions, combustion in power plants and wood burning and pose the greatest health risk.

To conduct the study, data on annual county-level PM2.5 levels were obtained from the Centers for Disease Control and Prevention (CDC). PM2.5 exposure was classified as high or low according to World Health Organization (WHO) standards.

The researchers collected data from the Centers for Disease Control and Prevention (CDC) on the average number of days (standardized by age) that county residents experienced mental health problems, including stress, depression and emotional problems. Each county was then divided into three groups based on these numbers. Counties in the top third reported the highest number of poor mental health (PMH) days. Age-adjusted rates of premature cardiovascular mortality (under age 65) by county were obtained from the CDC. County characteristics were obtained from the County Health Ranking Project.

Study of 315 million people

In 2013, the study included 3,047 U.S. counties with 315,720,938 residents (more than 207 million ages 20 to 64 and 50% women). Between 2013 and 2019, approximately 1,079,656 (0.34%) participants died from cardiovascular disease before age 65. The researchers analyzed the relationship between environmental pollution, mental health and premature cardiovascular mortality after adjusting for factors that might influence the relationship.

Counties with dirty air (high PM2.5 concentrations) were 10% more likely to report high numbers of PMH days compared to counties with clean air (low PM2.5 concentrations). This risk was especially higher in counties with a high prevalence of minority groups or poverty. The association between PMH and premature mortality from cardiovascular disease was stronger in counties with higher levels (above WHO recommended levels: ≥10 μm). ² ) air pollution.

In these counties, higher levels of PMG were associated with a threefold increase in premature cardiovascular mortality compared with lower levels of PMG. Moreover, one third of the risk of premature cardiovascular death associated with environmental pollution is explained by the higher burden of PMH.

Double threat

Dr Abohashem said: “Our findings show the double threat of air pollution: not only does it worsen mental health, but it also significantly increases the risk of cardiovascular deaths associated with poor mental health. Public health strategies to improve air quality and mental well-being are urgently needed to maintain cardiovascular health.”

Pollution levels in EOC countries can be seen in the EOC Cardiac Atlas.