Association of lipid-lowering drugs with the risk of type 2 diabetes and its complications: a mendelian randomized...

The pathogenesis of type 2 diabetes mellitus is somewhat associated with lipid metabolism. We aim to assess the impact of lipid-lowering drugs (HMGCR inhibitors, PCSK9 inhibitors, and NPC1L1 inhibitors) on type 2 diabetes mellitus and its complications through a two-sample Mendelian randomization (MR) study.

We identified suitable genetic instruments from the GWAS database that represent the expression levels of three genes, interpreting reduced genetically proxied gene expression as indicative of lipid-lowering drug use. We evaluated the causal relationships among these variables employing a two-sample Mendelian randomization approach, with the Inverse Variance Weighted (IVW) analysis serving as the primary method. Coronary artery disease was utilized as a positive control to validate the reliability of the selected genetic instruments.

Increased genetically proxied HMGCR expression is significantly associated with a reduced risk of type 2 diabetes mellitus (OR = 0.64, 95%CI = 0.55-0.74), which was replicated in the FinnGen study with consistent results (OR = 0.65, 95%CI = 0.53-0.80). Increased genetically proxied HMGCR expression is associated with a reduced risk of diabetic retinopathy (OR = 0.23, 95%CI = 0.12-0.44) and diabetic nephropathy (OR = 0.35, 95%CI = 0.17-0.71). In contrast, increased genetically proxied PCSK9 expression is associated with a decreased risk of diabetic coma (OR = 0.70, 95%CI = 0.50-0.98), diabetic neuropathy (OR = 0.24, 95%CI = 0.14-0.42), diabetic retinopathy (OR = 0.67, 95%CI = 0.48-0.96), diabetic cardiovascular diseases (OR = 0.62, 95%CI = 0.38-0.99), and diabetic nephropathy (OR = 0.62, 95%CI = 0.41-0.95).

This Mendelian randomization study suggests an association between HMGCR and the pathogenesis of type 2 diabetes mellitus, with increased genetically proxied HMGCR expression reducing the risk of type 2 diabetes mellitus, while PCSK9 and NPC1L1 show no significant association with type 2 diabetes mellitus. These findings may offer more reasonable lipid-lowering drug options for patients with dyslipidemia.