Systemic immune-inflammation index (SII) but not platelet-albumin-bilirubin (PALBI) grade is associated with severity of acute ischemic stroke (AIS)

Abstract

Introduction Inflammation plays an important role in stroke. Many inflammatory markers in peripheral blood are proved to be associated with stroke severity or prognosis. But few comprehensive models or scales to evaluate the severity of stroke have been reported. Systemic immune-inflammation index (SII) and platelet-albumin-bilirubin (PALBI) grade as new markers of inflammation have shown their positive association with liver cancer. The relation between SII, or PALBI and stroke remains uncertain. Objective To investigate the relationship between SII, PALBI grade and stroke severity. Methods Patients with ischemic stroke with hospital admission <24 h after symptom onset were prospectively included in a stroke registry. Demographic, clinical, and laboratory data were collected immediately after admission in all patients. The National Institutes of Health Stroke Scale (NIHSS) was used to assess stroke severity upon admission. Minor stroke was defined as NIHSS score < =5, moderate-to-severe stroke as NIHSS score >5. SII, calculated as platelet × neutrophil/lymphocyte was divided into four groups according to interquartile range: lowest SII (SII < 353.9 × 109/L), low SII (353.9–532.8 × 109/L), high SII (532.8–783.9 × 109/L), and highest SII (>783.9 × 109/L) group. Results A total of 362 patients with ischemic stroke were included, and between minor and moderate-to-severe stroke significant difference was found in SII (p < 0.0001), NLR (p < 0.0001), and PLR (p = 0.001), respectively. After multivariate regression analyses, SII groups (Odd ratio = 1.351, 95% confidence interval 1.084–1.684, p = 0.007) not PALBI was an independent risk factor for stroke severity. Conclusion We found that SII but not PALBI, which both are markers of inflammation, was independently associated with stroke severity.