PM2.5 associates with blood pressure: a Mendelian randomization analysis

Area of Science:

• Environmental Health
• Cardiovascular Epidemiology
• Genetic Epidemiology

Background:

• The association between fine particulate matter (PM2.5) and blood pressure (BP) remains controversial.
• Understanding the causal relationship is crucial for public health interventions.

Purpose of the Study:

• To investigate the causal effect of fine particulate matter (PM2.5) on blood pressure (BP) using a two-sample Mendelian randomization (MR) analysis.
• To clarify the controversial link between PM2.5 exposure and hypertension.

Main Methods:

• Utilized a two-sample Mendelian randomization (MR) design.
• Employed 58 genome-wide significant single-nucleotide polymorphisms (SNPs) associated with PM2.5 as instrumental variables.
• Applied inverse-variance weighted (IVW) as the primary analysis, with MR-Egger and weighted median methods for sensitivity analyses.

Main Results:

• A significant negative causal association was found between genetically predicted PM2.5 levels and systolic blood pressure (SBP).
• Each 1-SD increase in genetically predicted PM2.5 was associated with a decrease in SBP (IVW: β = -0.14, 95% CI [-0.25, -0.03]; Weighted Median: β = -0.13, 95% CI [-0.22, -0.04]).
• No significant causal relationship was observed between PM2.5 and diastolic blood pressure (DBP).

Conclusions:

• Increased exposure to fine particulate matter (PM2.5) may causally lead to decreased systolic blood pressure (SBP).
• These findings offer novel insights into the complex relationship between air pollution and cardiovascular health.