Park S, Lee S, Kim Y, et al. - Causal decrease in renal function by nonalcoholic fatty liver disease (NAFLD) was evident in this Mendelian randomization study.

• There exists an observational link between NAFLD and kidney function impairment.

• A significant association between a genetic predisposition for NAFLD (determined either by the single SNP rs738409 or by the group of variants) and a reduced estimated glomerular filtration rate (eGFR) was found even with adjustment for metabolic disorders, in the UK Biobank.

• The links were not significant in the negative control subgroups (body mass index < 30 kg/m ² , absence of central obesity, and serum alanine aminotransferase level ≤ 20 IU/mL) with a low likelihood of developing NAFLD.

• However, the associations were significant in the subgroups with a remaining risk of NAFLD, indicating the absence of a horizontal pleiotropic pathway.