Causal relationship between breakfast skipping and myocardial infarction: Two-sample Mendelian randomization

Area of Science:

• Cardiovascular Epidemiology
• Genetic Epidemiology
• Nutritional Epidemiology

Background:

• Observational studies indicate a link between skipping breakfast and myocardial infarction (MI).
• The causal relationship between breakfast skipping and MI remains unclear.
• Mendelian randomization (MR) can help infer causality using genetic variants.

Purpose of the Study:

• To investigate the potential causal relationship between habitual breakfast skipping and the risk of MI using MR.
• To leverage large-scale genetic data to assess the impact of breakfast skipping on heart attack risk.
• To provide evidence-based insights into the role of breakfast consumption in cardiovascular health.

Main Methods:

• Mendelian randomization (MR) analysis using genetic variants associated with breakfast skipping and MI.
• Inverse variance-weighted (IVW) method as the primary analysis, with MR-Egger, weighted median, and mode analyses for robustness.
• Heterogeneity (Cochrane Q, MR-Egger intercept) and pleiotropy (MR-PRESSO) tests were performed.
• Sensitivity analyses, including leave-one-out analysis, were conducted to ensure result reliability.

Main Results:

• A significant association was found between breakfast skipping and an increased risk of MI (OR: 1.34, 95% CI: 1.03–1.76, P=0.027).
• No evidence of heterogeneity or horizontal pleiotropy was detected.
• Sensitivity analyses confirmed the robustness and reliability of the primary findings.

Conclusions:

• Habitual breakfast skipping may causally increase the risk of myocardial infarction.
• Regular breakfast consumption could be a modifiable factor in reducing the likelihood of heart attacks.
• This MR study provides strong genetic evidence supporting the importance of breakfast for cardiovascular health.