Assessing Causality Between Second-Hand Smoking and Potentially Associated Diseases in Multiple Systems: A Two-Sample...

Area of Science:

• Epidemiology
• Genetic Epidemiology
• Public Health

Background:

• Secondhand smoke (SHS) exposure is a global health concern, with workplaces being a significant source.
• Observational studies suggest SHS is linked to various diseases, but establishing causality is challenging.

Purpose of the Study:

• To investigate the causal relationship between workplace SHS exposure and associated diseases using Mendelian randomization (MR).

Main Methods:

• Utilized summary statistics from UK Biobank, FinnGen, and European Bioinformatics Institute for European participants.
• Employed MR with inverse variance weighted (IVW), MR-Egger, and weighted median methods.
• Conducted sensitivity analyses to validate causal findings.

Main Results:

• Genetically determined atrial fibrillation (AF) and stroke showed a robust causal association with workplace SHS exposure (IVW model).
• Suggestive associations were observed between workplace SHS and myocardial infarction (MI), asthma, and depression.

Conclusions:

• Workplace SHS exposure is a causal risk factor for AF and stroke in European populations.
• Further research is needed to explore causality with other diseases potentially linked to SHS.
• Findings support the advancement and implementation of smoke-free policies.