APOB and type 2 diabetes mellitus: Although the causal relation between the metabolites and CVD in people with DKD is not yet fully understood, Mendelian randomisation studies have suggested TRLs and ApoB are causally associated with CVD [14, 15]; phenylalanine has been associated with type 2 diabetes [16], impaired kidney function [9], heart failure [17] and CVD [18] in large cohort studies.