Letter to the Editor: Post-transplant diabetes mellitus prevention in renal transplantation - are we missing vitamin D?

Post-transplant diabetes mellitus (PTDM) affects 10% to 40% of solid organ transplant recipients and is associated with adverse graft and cardiovascular outcomes. We read with interest the observational study published in the World Journal of Nephrology by Singh et al. This study suggests an association between vitamin D status and the risk of post-transplant diabetes mellitus. Evidence from the general population demonstrates that low serum 25-hydroxyvitamin D levels are associated with an increased risk of type 2 diabetes mellitus. Vitamin D deficiency affects over 80% of patients with end-stage kidney disease and commonly persists after transplantation. Vitamin D deficiency may worsen post-transplant glucose control by impairing anti-inflammatory pathways, reducing insulin sensitivity, and compromising pancreatic β-cell function. These actions are particularly important in patients receiving calcineurin inhibitors and glucocorticoids, which are major contributors to impaired insulin secretion. In PTDM, vitamin D status merits renewed attention as a modifiable factor influencing post-transplant glycemic control. Well-designed supplementation trials are needed to determine whether correcting vitamin D deficiency can meaningfully reduce PTDM incidence and improve graft outcomes.