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Association between modifiable risk factors and bradyarrhythmia: A Mendelian randomization study
Wanqian Pan1, Yujia Wu2, Chenyang Jin3
1Department of Cardiology, The First Affiliated Hospital of Soochow University, Jiangsu, China; Department of Cardiovascular Medicine, Hainan Medical University First School of Clinical Medicine: The First Affiliated Hospital of Hainan Medical University, Haikou, China.
Heart Rhythm
|October 17, 2025
Summary
Modifiable factors like body mass index and blood pressure causally increase the risk of bradyarrhythmia (slow heart rate). Understanding these links is key for developing prevention strategies for conditions like sick sinus syndrome and conduction disorders.
Area of Science:
- Cardiovascular Genetics
- Epidemiology
- Internal Medicine
Background:
- Bradyarrhythmia is linked to poor health outcomes.
- Effective primary prevention strategies for bradyarrhythmia are currently lacking.
Purpose of the Study:
- To investigate causal relationships between modifiable risk factors and bradyarrhythmia.
- Utilized Mendelian randomization (MR) to assess these associations.
Main Methods:
- Employed summary statistics from European-ancestry genome-wide association studies.
- Conducted univariable, multivariable, and mediation MR analyses.
- Applied Bonferroni correction for statistical significance (Padj <0.0023).
Main Results:
- Genetically predicted higher body mass index (BMI) was suggestively linked to sick sinus syndrome.
- Increased BMI, systolic blood pressure (SBP), diastolic blood pressure (DBP), and lipoprotein(a) were significantly associated with conduction disorders (CD).
- BMI and SBP were linked to atrioventricular block; SBP and DBP to left bundle branch block. SBP and DBP mediated BMI's effect on CD.
Conclusions:
- Identified specific modifiable metabolic and lifestyle factors causally linked to various bradyarrhythmia types.
- Findings offer insights into potential targets for bradyarrhythmia prevention.
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