All analyses were performed using the MR-Base “TwoSampleMR” v0.4.9 package11 in R. To avoid bias in the MR estimates due to linkage disequilibrium (r2), clumping was applied using the “clump_data” function with an r2 < 0.001. Genetic variants were required to be available in both the exposure and outcome traits and were harmonised using the default parameters within the TwoSampleMR package. Following this harmonisation, we only examined causal relationships where there were at least 30 instrumental genetic variables.
