Major study of 59 million Americans finds fine particulate matter from air pollution increases heart disease risks.

In a recent study published in BMJ, researchers assessed exposure-response relationships between chronic fine-size particulate matter (PM2.5) exposure and the probability of first-time hospitalization for cardiovascular disease (CVD) subgroups.

PM2.5, a minor component of air pollution, contributes considerably to CVD by inducing inflammation, vasoconstriction, cardiac electrical abnormalities, and blood clot formation.

Chronic exposure raises the risk of CVD-related hospitalization and death. Studies frequently focus on one or two CVD subtypes, neglecting to detect susceptible ones.

Comparing effect sizes across subtypes might help us understand processes and advise targeted strategies to lessen the impact of PM2.5.

The research included 59,761,494 individuals with 476,953,892 follow-up years; the majority were white (84%), with a higher number of female beneficiaries (55%). Most participants (75%) were between the ages of 65 and 74 when they began the research.

During the trial, 18% of participants registered with Medicaid. 22% required hospitalization due to a combination of cardiovascular diseases. The most frequent CVD subtype was ischemic heart illness, which affected 8.8% of recipients.

Other common illnesses were cerebrovascular disease (7.7%), heart failure (6.6%), and arrhythmia (6.5%). Three-year mean exposure to PM2.5 was related to an increase in the relative risk of initial hospitalization for cerebrovascular illnesses, ischemic heart diseases, cardiomyopathy, heart failure, abdominal and thoracic aortic aneurysms, and arrhythmia.

The study findings showed that chronic exposure to fine-sized particulate matter increases the risk of cerebrovascular illnesses, ischemic heart diseases, cardiomyopathy, heart failure, arrhythmia, and abdominal and thoracic aortic aneurysms.

Exposure-response curves for several CVD subtypes shifted, indicating a lack of a safe threshold for cardiovascular health. Adhering to the WHO's air quality standards of ≤5 µg/m3 can provide considerable advantages. Susceptibility varied by participant age, healthcare access, educational achievement, and neighborhood deprivation.

Cardiac arrhythmia and heart failure are among the most vulnerable CVD subtypes in patients exposed to PM2.5.