Air pollution tied to hospital admissions for heart disease

Editor's Note

Data published February 21 in The BMJ points to air pollution as a factor in increased hospital admissions for major heart diseases. 

According to the Global Burden of Disease study, exposure to fine particulate matter (PM2.5) accounts for 7.6% of total mortality and 4.2% of disability-adjusted life years (a measure of years lived in good health). Findings from the study, which aims to quantify health loss from hundreds of diseases, illnesses, and risk factors, led the World Health Organization (WHO) to update air quality guidelines in 2021. 

The more recent BMJ report details a population-based cohort study that examined 60 million US adults along with Medicare insurance data from 2000 to 2016. This research links three-year average exposure to average PM2.5 levels (9.7 ug/m3) to increased risk of hospital admission for 7 major cardiovascular diseases, including heart failure, ischemic heart disease, and arrhythmia. The findings indicated that the cardiovascular effects from air pollutant exposure persisted for at least three years following the exposure with variations in susceptibility based on age, education, and access to health care services.

The researchers conclude that while there is no safe threshold for exposure to fine particulate matter for cardiovascular health. However, there could be significant health benefits to meeting WHO air quality guidelines, which recommend exposures of 5 μg/m3 or less. If that could be achieved, “we could avoid 23% in hospital admissions for cardiovascular disease,” they write.