Fig. 3

Putative causal circulating metabolites of four DR outcomes identified by univariable and multivariable Mendelian randomization analyses. A. The heatmap illustrated the effects of 26 causal circulating metabolites with robust evidence on four diabetic retinopathy (DR) outcomes identified through univariable Mendelian randomization (UVMR) analyses. These included 11 metabolites for overall DR, 5 for background DR, 1 for severe background DR, and 9 for proliferative DR (PDR). B. The forest plots depicted the results of multivariable Mendelian randomization (MVMR) analyses using the MR-BMA method. These analyses identified 8 out of the 11 causal metabolites for overall DR, 1 out of the 5 for background DR, and 2 out of the 9 for PDR, considering the combined impact of these metabolites