Systemic Immune-Inflammation Index and Long-Term Mortality in Patients with Stroke-Associated Pneumonia

Abstract

Background: Systemic immune inflammation has been investigated as a prognostic marker of different diseases. This study is designed to assess the association of systemic immune-inflammation index (SII) with long-term mortality of stroke-associated pneumonia (SAP) patients. Methods: Patients aged ≥18 years with SAP were selected from the Nanjing Stroke Registry Program in China. We retrospectively evaluated systemic immune-inflammation response with SII and pneumonia severity with the pneumonia severity index and the confusion, uremia, elevated respiratory rate, hypotension, and aged 65 years or older score. To explore the correlation between SII and mortality in SAP patients, multivariable Cox regressions and competing risk regressions were conducted. Mediation analysis was also performed to assess the role of pneumonia severity. Results: Among 611 patients in the SAP population, death occurred in 164 patients (26.8%) during the median follow-up of 3.0 (1.2-4.6) years. In multivariate analysis, higher SII scores could predict increased mortality in patients with SAP (adjusted hazard ratio 2.061; 95% confidence interval, 1.256-3.383; P = 0.004), and the association was mediated by pneumonia severity. Moreover, adding SII to traditional models improved their predictive ability for mortality. Conclusion: Our study displayed that SII was characterized in SAP patients with different prognoses. Elevated SII scores increased the risk of mortality. Further research is required for the clinical practice of the index among SAP patients.

Use of the systemic immune-inflammation index to predict the severity of pneumonia in the emergency department

“…However, the presence of a history of malignancy among their patients may have affected the SII values. Examining long-term mortality in patients with ischaemic stroke who developed SAP, Xie et al determined that SII values successfully predicted long-term mortality [13]. In the present study, patients with conditions that could affect SII values, such as a history of malignancy, were excluded from the study.…”

“…In addition, pneumonia was the main reason for presentation to the emergency department among the patients selected for this study. Therefore, this study differs from previous studies in which cases of pneumonia that developed during another disease were examined (11)(12)(13). The study's patient selection was similar to that of Acar et al, who investigated the use of SII values in determining clinical severity and 28-day mortality in patients with community-acquired pneumonia [14].…”

Association between systemic immune-inflammation index and insulin resistance and mortality

“…It is worth noting that our study fully accounted for the robust association between SII and all-cause mortality, aligning with the findings of a prior study. This study examined the link between SII and long-term mortality in patients with stroke-associated pneumonia, revealing a substantial association between SII and mortality 46 .…”

Association of the systemic immune-inflammation index with all-cause and cardiovascular mortality in individuals with rheumatoid arthritis

“…Existing literature has highlighted a link between elevated SII levels and an increased risk of mortality both in the general population and among individuals with conditions characterized by significant inflammatory processes 28 – 31 . Regarding the acute ischemic stroke in intensive care units, one study identified a positive, albeit non-linear, relationship between SII and in-hospital mortality 11 , as well as in individuals with stroke-associated pneumonia 32 . Furthermore, research has shown that SII is associated with a heightened risk of mortality in adults with asthma 33 .…”