Independent predictive role of nutritional markers in kidney function decline and mortality in diabetes

Malnutrition and chronic inflammation are common in chronic kidney disease (CKD) and contribute to disease progression and mortality. While the prognostic nutritional index (PNI), geriatric nutritional risk index (GNRI), and controlling nutritional status (CONUT) scores assess nutritional status, their predictive values for CKD progression and mortality in individuals with diabetes, particularly independent of tumor necrosis factor receptor 2 (TNFR2), remains unclear. This study aimed to evaluate whether these markers predict outcomes beyond TNFR2.

We analyzed 640 individuals with diabetes, stratified by PNI quartiles (Q1 vs. Q2-4). Serum TNFR2 was measured using enzyme-linked immunosorbent assay. Nutritional status was assessed using PNI, GNRI, and CONUT scores. Cox proportional hazards models adjusted for covariates including TNFR2 examined associations between nutritional markers and a kidney event (≥30 % decline in estimated glomerular filtration rate), mortality, and a composite outcome.

The mean age was 65 years; 53.9 % were male. Over median follow-ups of 5.3 and 5.4-years, 75 (11.7 %) experienced a kidney event and 44 (6.9 %) died. A total of 112 (17.5 %) experienced the composite outcome. All three markers were independently associated with a kidney event (PNI: hazard ratio [HR], 1.84; 95 % confidence interval [CI], 1.13-3.02) and a composite outcome (PNI: HR, 1.94; 95 % CI, 1.30-2.89). GNRI was the only marker independently associated with mortality (HR, 2.90; 95 % CI, 1.56-5.37).

PNI, GNRI, and CONUT scores strongly predict adverse outcomes in diabetes, emphasizing the importance of nutritional evaluation. Targeted nutritional interventions may improve prognosis.