Causal Association Between Anemia and Cardiovascular Disease: A 2-Sample Bidirectional Mendelian Randomization Study

Area of Science:

• Cardiovascular Medicine
• Genetics
• Epidemiology

Background:

• Observational studies suggest a link between anemia and cardiovascular disease (CVD), but causal relationships remain unclear.
• Understanding the bidirectional causality between anemia and CVD is crucial for clinical management.

Approach:

• A 2-sample bidirectional Mendelian randomization (MR) study was conducted using summary statistics from genome-wide association studies.
• Multiple analytical methods and sensitivity analyses were employed to ensure result robustness.
• Meta-analysis combined findings from various studies, including UK Biobank and FinnGen.

Key Points:

• Genetically predicted anemia showed a significant causal association with increased heart failure risk (OR, 1.11) and a suggestive association with coronary artery disease risk (OR, 1.11).
• Reverse MR analysis revealed that genetic predisposition to heart failure (OR, 1.64), coronary artery disease (OR, 1.16), and any ischemic stroke (OR, 1.30) significantly increases anemia risk.
• Sensitivity analyses indicated minimal horizontal pleiotropy and heterogeneity, supporting the reliability of the findings.

Conclusions:

• The study provides evidence for a bidirectional causal relationship between anemia and heart failure.
• Genetic predisposition to coronary artery disease and ischemic stroke is associated with an increased risk of anemia.