Prevention & lipidsCohort study

Exposure-response associations between chronic exposure to fine particulate matter and risks of hospital admission for major cardiovascular diseases: population based cohort study

BMJPublished

  • Population based cohort study
  • causal framework robust against confounding and exposure measurement error

Authors' conclusion

The findings of this study suggest that no safe threshold exists for the chronic effect of PM2.5 on overall cardiovascular health.

Study context

Population
Medicare fee-for-service beneficiaries aged ≥65 years, contiguous US, 2000–16
Participants
59,761,494 beneficiaries
Exposure
Chronic PM2.5 exposure levels
Outcome
First hospital admission for ischemic heart disease, cerebrovascular disease, HF, cardiomyopathy, arrhythmia, valvular heart disease, thoracic and abdominal aortic aneurysms, or composite CVD

Main finding

Composite CVD hospital admission

Relative risk

1.29

95% CI 1.28–1.30

By group

9–10 µg/m3 vs ≤5 µg/m3
RR 1.29 (95% CI 1.28–1.30)

As reported in the abstract

Observational data: associations, not effects.

Further findings

Cardiovascular disease (CVD) subtypes

3-year average PM2.5 associated with increased RR of first admission for ischemic heart disease, cerebrovascular disease, HF, cardiomyopathy, arrhythmia, and thoracic and abdominal aortic aneurysms

Persistence and effect modification

Effects persisted for at least 3 years after exposure
Age, education, healthcare accessibility and neighborhood deprivation appeared to modify susceptibility

Original publication

Exposure-response associations between chronic exposure to fine particulate matter and risks of hospital admission for major cardiovascular diseases: population based cohort study. BMJ. Published 21 February 2024. doi:10.1136/bmj-2023-076939

Summarised from the published abstract; every number is checked against it