Fig. 1

Principles of MR analysis for serum albumin level traits and risk of cardiovascular diseases outcomes and assumptions that need to be met to obtain unbiased estimates of causal effects. Broken lines represent potential pleiotropic or direct causal effects between variables that would violate MR assumptions. Three assumptions of MR: (1) genetic variants must be associated with serum albumin levels; (2) genetic variants must not be associated with confounders; (3) genetic variants must influence the risk of cardiovascular traits and disease outcomes only through serum albumin levels and not through any alternative pathways. MR: Mendelian randomization