Letter to the Editor: Vitamin D deficiency and post-transplant diabetes in kidney recipients - opportunity for risk stratification and intervention.

Vitamin D deficiency is highly prevalent worldwide, including in South Asia, and may contribute to dysglycemia by affecting insulin secretion, insulin sensitivity, and inflammation. Observational studies in the general population link lower 25-hydroxyvitamin D concentrations to a higher risk of incident type 2 diabetes, and emerging evidence suggests a similar relationship in kidney transplant recipients with post-transplant diabetes mellitus (PTDM). In this context, the prospective study published in the World Journal of Nephrology by Singh et al provides important evidence from a tropical setting, showing that pre-transplant 25-hydroxyvitamin D < 20 ng/mL was independently associated with PTDM at 1 year after kidney transplantation. In this correspondence, available global, regional, mechanistic, and transplant data are synthesized to argue that vitamin D deficiency should be considered a clinically relevant and potentially modifiable component of PTDM risk stratification, while acknowledging that causality remains unproven and residual confounding cannot be excluded.