The following is a summary of “A Mendelian randomization (MR) study on causal effects of 25(OH) vitamin D levels on diabetic nephropathy.,” published in the June 2023 issue of Nephrology by He et al.
The association between vitamin D supplementation and a reduced incidence of diabetic nephropathy (DN) exists, but the causative nature of this relationship remains uncertain.
For a study, researchers aimed to examine the 25(OH) vitamin-D levels in DN. They employed 2 samples, MR, to assess the causal impact of vitamin D on DN in 7,751 individuals with type I diabetes-related nephropathy (T1DN) and 9,933 individuals with type II diabetes-related nephropathy (T2DN). They replicated certain prior studies investigating the impact of KIM-1 (kidney injury molecule 1) and body mass index (BMI) on DN. Investigators reported that results of the MR analysis indicated no causal association between 25(OH) D levels and the early/later stages of T1DN (early: OR = 0.903, 95%CI: 0.229-3.555; later: OR = 1.213, 95%CI: 0.367-4.010) and T2DN (early: OR = 0.588, 95%CI: 0.182-1.904; later: OR = 0.904, 95%CI: 0.376-2.173), nor with the kidney function of patients with diabetes mellitus: eGFRcyea (creatinine-based estimated GFR) (Beta = 0.007, 95%CI: -0.355 to 0.369)) or UACR (urinary albumin creatinine ratio) (Beta = 0.186, 95%CI: -0.961 to 1.333)).
They found no causal link between vitamin D and DN or kidney function in patients with diabetes.
Source: bmcnephrol.biomedcentral.com/articles/10.1186/s12882-023-03186-2
