Supplementary Material for: Drug Target Mendelian Randomization Study of PCSK9 and HMG-CoA Reductase Inhibition and Atrial Fibrillation

Introduction: Atrial fibrillation (AF) is a prevalent cardiac arrhythmia with significant clinical implications. The potential influence of lipid-lowering therapies, specifically PCSK9 inhibitors (PCSK9i) and HMG-CoA reductase inhibitors (statins), on AF risk remains a topic of interest. This Mendelian Randomization (MR) study aimed to elucidate the causal relationship between genetically predicted inhibition of PCSK9 and HMG-CoA reductase and the risk of AF.
Methods: Utilizing publicly available, summary-level genome-wide association study (GWAS) data, we employed single-nucleotide polymorphisms (SNPs) associated with lower LDL-C levels as instruments for gene-simulated inhibition of PCSK9 and HMG-CoA reductase. Multiple MR techniques were applied to estimate the causal effects, and sensitivity analyses were conducted to validate the results.
Results: Genetically predicted inhibition of PCSK9 demonstrated a reduced risk of AF, with an odds ratio (OR) of 0.92 (95% CI: 0.85 to 0.99, p=0.01) using the inverse variance weighted (IVW) method. In contrast, the inhibition of HMG-CoA reductase did not exhibit a statistically significant association with AF risk (IVW: OR = 1.11, 95% CI: 1.00-1.22, p = 0.05).
Conclusion: Our MR study suggests that genetically predicted inhibition of PCSK9, but not HMG-CoA reductase, is associated with a lower risk of AF. These findings provide evidence for a causal protective effect of PCSK9i on AF and support the use of PCSK9i for AF prevention in patients with dyslipidemia. Further studies are needed to elucidate the mechanisms underlying the differential effects of PCSK9i and statins on AF and to confirm the clinical implications of our findings.