Combined nutritional and inflammatory risk stratification for predicting functional outcomes in acute ischemic stroke

Inflammation and malnutrition are both closely associated with adverse outcomes after acute ischemic stroke (AIS), yet their combined effect and potential interaction remain insufficiently understood. This study aimed to evaluate the prognostic value of combined nutritional and inflammatory risk stratification based on nutritional risk screening-2002 (NRS-2002) and neutrophil-to-lymphocyte ratio (NLR), and to explore whether inflammatory burden mediates the relationship between nutritional status and functional outcomes.

We retrospectively analyzed 1,167 consecutive patients with AIS admitted within 48 h of symptom onset. Nutritional status was assessed using NRS-2002, and inflammatory status was evaluated using admission NLR. Patients were categorized into four groups: low-Risk, inflammatory-risk, nutritional-risk, and dual-risk. The primary outcome was poor functional outcome at 3 months (modified Rankin Scale ≥3). Multivariable logistic regression models were used to examine associations. Predictive performance was evaluated using AUC, NRI, and IDI. Mediation analysis was conducted using NLR area under the curve (NLR-AUC) to assess the indirect effect of inflammation.

Compared with the low-risk group, the inflammatory-risk, nutritional-risk, and dual-risk groups were all independently associated with increased risk of poor functional outcomes (all P < 0.05). The dual-risk group showed the highest risk (fully adjusted OR = 3.59, P < 0.001). Nutritional-inflammatory risk stratification demonstrated superior predictive performance compared with traditional nutritional indices (all P < 0.05). Although it did not significantly improve AUC when added to the totaled health risks in vascular events (THRIVE) score, it significantly enhanced continuous NRI and IDI (both P < 0.05). Mediation analysis revealed that inflammatory burden partially mediated the association between malnutrition and poor outcomes in the basic model (mediation proportion: 8.73%), but this effect was attenuated after full adjustment.

Combined assessment of nutritional and inflammatory status provides meaningful risk stratification for functional outcomes in AIS. Malnutrition and systemic inflammation exert a synergistic effect on post-stroke prognosis, while inflammation may partially mediate this relationship but is not independent of key clinical factors.