ASSOCIATION OF PROGNOSTIC NUTRITIONAL INDEX (PNI) AND THE 30-DAY MORTALITY IN ICU PATIENTS WITH ACUTE KIDNEY INJURY: A RETROSPECTIVE COHORT STUDY

Acute Kidney Injury (AKI) is a severe complication among critically ill patients, particularly those in the Intensive Care Unit (ICU), and is associated with high morbidity and mortality. Malnutrition is recognized as a risk factor for poor health outcomes; however, its impact on the prognosis of acute kidney injury (AKI) remains underexplored. The Prognostic Nutritional Index (PNI), a simple tool based on serum albumin levels and total lymphocyte count, has been widely used to assess nutritional and immunological status, but its predictive value in ICU patients with AKI lacks sufficient investigation, particularly in local settings. This study aimed to determine the association between Prognostic Nutritional Index (PNI) and 30-day mortality in ICU patients with Acute Kidney Injury

We conducted a retrospective cohort study involving adult patients with Acute Kidney Injury admitted to the Medical Intensive Care Unit from June 2021 to June 2023. Demographic and clinical data were collected by reviewing the electronic medical records. Patients were grouped as either expired (died within 30 days of ICU admission) or survived (alive within 30 days of ICU admission). The use of PNI score was assessed in all patients. Univariate and multivariate analysis were done to determine the association of PNI score and 30-day all-cause mortality among AKI patients at the medical ICU

The study included 209 patients, of whom 138 (66%) died within 30 days of ICU admission, and 71 (34%) who survived. Most of the patients (55%) had AKI Stage III. The median length of ICU stay was 11.5 days while the mean serum creatinine levels in the expired and surviving groups were 217.8 umol/L and 230.9 umol/L, respectively. Most patients (68.9%) had a PNI score of < 35 and were classified as having a severe risk for malnutrition, 13.9% were under moderate risk, and 17.2% were under normal risk for malnutrition. One hundred and five patients (50.2%) showed AKI resolution. Sixty-nine percent of the patients were weaned off dialysis. The mean SOFA and GCS scores were 8.0 and 9.6, respectively. The majority of patients (95.2%) received mechanical ventilation and 143 individuals did not receive vasopressor. There was an association between the PNI score and all-cause mortality among AKI patients in the ICU in the unadjusted model (crude OR = 2.2 (1.2 to 4.0), p = 0.013). However, after multiple predictor logistic regression analysis, AKI nonresolution (adjusted OR = 10 (4.5 to 23), p = 0.001), SOFA (adjusted OR = 1.3 (1.1 to 1.5), p = 0.001), and GCS (adjusted OR = 0.8 (0.6 to 1.0), p = 0.015) scores remained significantly associated with 30-day all-cause mortality.

Prognostic Nutritional Index (PNI) is a potential predictor of 30-day mortality among ICU patients with AKI but should not be used in isolation but rather in conjunction with other clinical parameters in risk stratification such as SOFA and GCS score. Further prospective studies are needed to confirm the association between PNI and short-term mortality in patients with AKI.

This abstract was also submitted for the Korean Society of Nephrology Congress 2025