Transient ischemic attack and coronary artery disease: a two-sample Mendelian randomization analysis.

Area of Science:

• Cardiovascular Epidemiology
• Genetic Epidemiology
• Causal Inference

Background:

• Observational studies suggest a link between transient ischemic attacks (TIAs) and increased risk of coronary artery disease (CAD).
• The causal relationship between TIAs and CAD remains unclear.
• Genetic association studies provide tools to investigate causality.

Purpose of the Study:

• To investigate the potential causal relationship between TIAs and CAD.
• To utilize Mendelian randomization (MR) to assess causality.

Main Methods:

• A two-sample Mendelian randomization (MR) study was conducted.
• Genome-wide association study data from FinnGen was used.
• Inverse-variance weighted (IVW) method was the primary analysis technique, with MR-Egger, weighted median, MR-PRESSO, and multivariable MR used for robustness checks.

Main Results:

• The IVW method indicated that TIAs are associated with an increased risk of coronary artery atherosclerosis (OR 1.17, P=0.002), ischemic heart disease (OR 1.15, P=0.007), and myocardial infarction (OR 1.15, P=0.025).
• Heterogeneity and horizontal pleiotropy were detected for ischemic heart disease.
• Sensitivity analyses did not reveal horizontal pleiotropy for other outcomes.

Conclusions:

• This MR study provides evidence for a potential causal link between TIAs and CAD.
• Further research is warranted to elucidate the underlying mechanisms.