Causal relationship between particulate matter 2.5 and infectious diseases: A two-sample Mendelian randomization...

Area of Science:

• Environmental Health
• Epidemiology
• Genetics

Background:

• Previous observational studies indicated a link between PM2.5 and infectious diseases, but causality was unproven.
• Particulate matter 2.5 (PM2.5) exposure is a global health concern with potential links to various infections.

Purpose of the Study:

• To investigate the causal relationship between PM2.5 concentrations and multiple infectious diseases using Mendelian randomization.
• To determine if PM2.5 exposure causally affects the risk of COVID-19 infection, hospitalization, and severity, as well as other infections like urinary tract infections, bacterial pneumonia, and intestinal infections.

Main Methods:

• Mendelian randomization (MR) analysis was employed as the primary methodology.
• Inverse variance weighted (IVW) was the main analysis method, supplemented by MR-Egger, weighted median, and maximum likelihood methods.
• Sensitivity analyses included Cochrane's Q test, MR-Egger intercept, MR-PRESSO, and leave-one-out tests to ensure robustness and assess pleiotropy.

Main Results:

• A significant causal effect was found where elevated PM2.5 concentration increases the risk of hospitalized COVID-19 (OR=1.91) and very severe COVID-19 (OR=3.29).
• No causal effect of PM2.5 on urinary tract infection, bacterial pneumonia, or intestinal infection was identified.
• Sensitivity analyses confirmed the reliability of the significant causal associations found for COVID-19.

Conclusions:

• Lifetime exposure to elevated PM2.5 concentrations is causally linked to an increased risk of hospitalized and severe COVID-19.
• Findings suggest that air pollution control strategies could be beneficial in mitigating COVID-19 progression and severity.
• Targeted interventions to reduce PM2.5 exposure may be a viable public health strategy for managing COVID-19.