A Household Appliance That Lowers Blood Pressure by 3mmHg? New Insights on Air Purifiers That May Also Reduce the Risk of Myocardial Infarction

The French publication Medisite highlighted air purifiers as "home appliances that could lower the risk of myocardial infarction." This claim is based on a randomized crossover trial published in the Journal of the American College of Cardiology (JACC) on August 6, 2025. The study involved 154 adults living near major roads and compared the effects of using HEPA air purifiers versus placebo devices for one month each. Among individuals with higher baseline systolic blood pressure, a significant reduction was observed when using HEPA purifiers (an average decrease of about 2.8 mmHg, with a total difference of about 3 mmHg compared to the placebo). However, reports also indicate that the overall average difference was small, suggesting that the effect is more pronounced in those with higher blood pressure. Particulate matter (PM) is a major risk factor for hypertension and coronary artery disease, and its infiltration into living spaces is a growing concern. On social media, opinions are divided, with comments noting "a small but clinically meaningful difference," "the importance of combining with ventilation," and "cost/filter replacement challenges." Air purifiers are not a cure-all but should be considered as part of a comprehensive strategy alongside salt reduction, exercise, and medication.