The prognostic nutritional index as a risk factor for severe COVID-19 infection among hospitalized patients: A multicenter historical cohort study.

Introduction: Malnutrition is a critical prognostic factor in COVID-19, affecting up to 50 % of hospitalized patients and increasing their mortality risk tenfold compared to well-nourished patients. The prognostic nutritional index (PNI) assesses nutritional and immune status and can help gauge the severity of COVID-19.

Objective: To evaluate whether PNI was independently associated with the severity of COVID-19 infection among hospitalized patients in the United States.

Methods: This study was a historical cohort study of adult patients with COVID-19 hospitalized in five hospitals in southeast Michigan. Data collected from the electronic medical record were analyzed using SPSS v. 29.0, and a p-value <0.05 was considered statistically significant.

Results: Data were included on 286 patients, with a mean age of 58.7 ± 17.5 years, 53.5 % (153/286) female, and 48.3 % (138/286) black/African American. The most common comorbidities were hypertension (62.9 %), obesity (54.2 %) and type 2 diabetes mellitus (32.1 %). Of the 286 patients, 144 (50.3) had severe/ critical disease. Patients with severe COVID-19 had significantly lower mean PNI levels than those with mild to moderate disease (35.1 ± 5.2 vs 37.7 ± 6.4, p < 0.001). After controlling for smoking status, vaccination status, race, and home steroid use, PNI remained an independent predictor for severe/ critical COVID-19 (OR=0.92, p < 0.001).

Conclusions: This study demonstrated that PNI is an independent predictor of severe COVID-19. The PNI score can be easily calculated from routine blood tests for every patient and helps risk stratify hospitalized COVID-19 patients. Additional research is needed to confirm these results.