Early Post-Transplant Changes in Nutritional Status Predict Long-Term Graft Loss and Mortality.

Background

Nutritional status is an important determinant of outcomes after kidney transplantation, yet the prognostic significance of longitudinal changes in nutritional indices remains insufficiently investigated. We evaluated whether first-year changes in the Prognostic Nutritional Index (PNI) and Controlling Nutritional Status (CONUT) score were associated with long-term adverse outcomes in kidney transplant recipients (KTRs).

Methods

This retrospective cohort study included 352 adult KTRs with a median follow-up of 11.4 years. PNI and CONUT were calculated before transplantation and at the first post-transplant year. Patients were categorized according to changes in nutritional status as improved/stable or worsened. The primary outcome was a composite of end-stage renal disease (ESRD) or death with a functioning graft. Two separate multivariable logistic regression models were constructed to evaluate the associations of changes in first-year PNI and CONUT with the composite outcome after adjustment for clinically relevant demographic and transplant-specific variables, including first-year rejection episodes, estimated glomerular filtration rate (eGFR), and urine protein-to-creatinine ratio (PCR). Additional analyses were performed separately for graft loss and death with a functioning graft.

Results

Baseline PNI and CONUT scores were comparable between patients with and without adverse outcomes. Patients who reached the composite outcome had significantly lower first-year eGFR (p = 0.001), whereas first-year rejection episodes and urine PCR were similar between the groups. After multivariable adjustment, worsening first-year PNI (OR: 2.02, 95% CI: 1.08-3.77, p = 0.028) and worsening first-year CONUT (OR: 2.01, 95% CI: 1.11-3.65, p = 0.022) remained independently associated with the composite outcome. Higher first-year eGFR was independently associated with a lower risk of adverse outcomes. Separate analyses of graft loss and death with a functioning graft supported the primary findings, with stronger associations observed for graft-related outcomes.

Conclusions

Early deterioration in nutritional status, reflected by worsening changes in PNI and CONUT during the first post-transplant year, was independently associated with adverse long-term outcomes in KTRs. Serial assessment of these simple and inexpensive nutritional indices may improve long-term risk stratification and help identify patients who could benefit from closer clinical follow-up and individualized nutritional assessment.