Microplastics and Nanoplastics in Atheromas and Cardiovascular Events.
Level 3 - non-randomized controlled study
Prospective multicenter observational cohort study
PubMed 38446676 · doi:10.1056/NEJMoa2309822
What was done
This prospective, multicenter observational study followed patients undergoing carotid endarterectomy for asymptomatic carotid artery disease. Excised carotid plaque specimens were analyzed for microplastics and nanoplastics (MNPs) using pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed via ELISA and immunohistochemistry. The primary outcome was a composite of myocardial infarction, stroke, or all-cause death, comparing patients with detectable plaque MNPs to those without detectable MNPs.
What was found
Of 304 enrolled patients, 257 completed follow-up (mean 33.7 ± 6.9 months). Polyethylene was detected in 150 patients (58.4%; mean 21.7 ± 24.5 μg per milligram of plaque), and polyvinyl chloride was detected in 31 patients (12.1%; mean 5.2 ± 2.4 μg per milligram). Electron microscopy showed jagged-edged foreign particles among macrophages and debris. Patients with detectable MNPs had a significantly higher risk of the primary composite end point than those without detectable MNPs (hazard ratio, 4.53; 95% CI, 2.00 to 10.27; P < 0.001).
Why it matters
This study provides direct human observational evidence associating the presence of microplastics and nanoplastics within vascular atheromas with an elevated risk of major adverse cardiovascular events and death.
Limits
The observational design cannot establish direct causation and remains susceptible to unmeasured confounding such as environmental, occupational, or lifestyle factors. The cohort was limited to patients undergoing endarterectomy for asymptomatic carotid disease, limiting generalizability to wider populations. In addition, 47 of 304 enrolled patients (15.5%) did not complete the mean 34-month follow-up.
Cited by
- supports A New England Journal of Medicine study found that microplastics present in arterial plaques are linked to an increased risk of cardiovascular events.