Nutritional status assessed by prognostic nutritional index and its association with lower extremity deep venous thrombosis: a retrospective study.

BACKGROUND

Deep venous thrombosis (DVT) is a frequent and potentially fatal complication of hospitalised patients in the lower extremities. Nutritional status affects immune function, coagulation, and recovery, but its relationship with LEDVT has not been adequately explored. The Prognostic Nutritional Index (PNI) is a straightforward marker that includes serum albumin and lymphocyte count and serves as an indicator of both nutritional and immune status.

PURPOSE: This research was done to examine the relationship between the PNI and LEDVT risk.

METHODS

This retrospective cohort study included 600 adult patients who underwent lower-limb duplex ultrasonography between January 2020 and December 2025. Clinical, demographic and laboratory data were gathered. PNI was calculated as: PNI = (10 × serum albumin [g/dL]) + (0.005 × total lymphocyte count [/mm3]). Patients have been divided into tertiles according to PNI. Logistic regression analyses were conducted to identify predictors of LEDVT, and the predictive performance of PNI was assessed using ROC curve analysis.

RESULTS

A total of 600 patients were studied, of whom 182 (30.3%) had LEDVT. The PNI of patients with LEDVT was significantly lower (41.1 ± 6.3) than that of patients without (48.2 ± 7.1, p < 0.001). The incidence of LEDVT declined steadily with increasing PNI tertiles (48.5, 29.0, and 13.5 in the low, moderate, and high PNI tertiles, respectively; p-trend <0.001). Lower PNI remained independently associated with LEDVT (adjusted OR 0.91/unit increase; 95% CI 0.88-0.94, p = 0.001) in multivariate analysis, alongside malignancy and immobilisation. Analysis of ROC curves revealed fair discriminative ability of PNI (AUC 0.74, 95% CI 0.70-0.78).

CONCLUSION

There is a positive association between lower nutritional status (PNI) and the risk of LEDVT in hospitalised patients. PNI may serve as an easy, cost-effective biomarker for LEDVT risk stratification.