The association between acute nutritional changes and prognosis in ischemic stroke patients

Nutritional status during the acute phase of ischemic stroke can change dynamically and may influence patient outcomes. However, the impact of short-term nutritional changes on prognosis remains unclear. This study aimed to investigate the association between acute-phase nutritional changes and 3-month functional outcomes, and to identify factors contributing to nutritional deterioration.

A prospective-retrospective cohort study was conducted including 1,445 patients with acute ischemic stroke admitted within 48 h of onset. Nutritional status was assessed using the Prognostic Nutritional Index (PNI) within 24 h of admission (PNI1) and on day 5 ± 1 of admission (PNI2). ΔPNI was calculated as PNI2 minus PNI1. Functional outcomes at 3 months were evaluated using the modified Rankin Scale (mRS), with mRS ≥3 defined as poor outcome. Logistic regression and restricted cubic spline analyses were performed to examine the association between ΔPNI and outcomes. Subgroup analyses explored potential effect modifiers, and linear regression identified determinants of nutritional changes.

PNI2 was significantly lower than PNI1 (45.75 vs. 46.70, p < 0.001). An increase in ΔPNI was independently associated with a decreased likelihood of poor 3-month outcomes (Model 4: OR per 5-unit increase = 0.744, 95% CI: 0.579-0.957, p = 0.021). Patients in the nutritional improvement group showed significantly better outcomes than those in the deterioration group (ΔPNI_ ± 1.5 OR: 0.559, 95% CI: 0.330-0.946, p = 0.030; ΔPNI/PNI1_ ± 3% OR: 0.556, 95% CI: 0.334-0.928, p = 0.025). Subgroup analyses indicated stronger associations in patients aged <65 years, males, those with large-artery atherosclerosis, mild stroke, or receiving intravenous thrombolysis. Older age, low baseline PNI, low body mass index, and nasogastric tube feeding were significant risk factors for nutritional deterioration.

Declines in nutritional status during the acute phase of ischemic stroke are independently associated with an increased risk of poor 3-month functional outcomes, particularly in specific patient subgroups. Patients with low baseline energy reserves, older age, or requiring nasogastric tube feeding are at higher risk of nutritional deterioration.