The predictive role of systemic inflammation response index in the prognosis of traumatic brain injury: A propensity score matching study

Baojie Mao; Lei Feng; Dongdong Lin; Yanfei Shen; Jiangchun Ma; Yuning Lu; Rui Zhang; Ming Wang; Shu Wan

doi:10.3389/fneur.2022.995925

The predictive role of systemic inflammation response index in the prognosis of traumatic brain injury: A propensity score matching study

Front Neurol. 2022 Nov 2:13:995925. doi: 10.3389/fneur.2022.995925. eCollection 2022.

Authors

Baojie Mao^{1

2}, Lei Feng^{1

2}, Dongdong Lin², Yanfei Shen³, Jiangchun Ma², Yuning Lu^{1

2}, Rui Zhang^{1

2}, Ming Wang², Shu Wan²

Affiliations

¹ The Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, China.
² Brain Center, Affiliated Zhejiang Hospital, Zhejiang University School of Medicine, Hangzhou, China.
³ Department of Intensive Care, Affiliated Zhejiang Hospital, Zhejiang University School of Medicine, Hangzhou, China.

Abstract

Background: We aimed to evaluate the predictive power of systemic inflammation response index (SIRI), a novel biomarker, to predict all-cause mortality in patients with traumatic brain injury (TBI) in the intensive care unit (ICU).

Methods: Clinical data were retrieved from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. Kaplan-Meier (KM) methods and cox proportional hazard models were performed to examine the association between SIRI and all-cause mortality. The predictive power of SIRI was evaluated compared to other leukocyte-related indexes including neutrophils, lymphocytes, monocytes and white blood cells (WBC) by the Receiver Operating Characteristic (ROC)curve for 30-day mortality. In addition, propensity score matching (PSM) was conducted to reduce confounding.

Results: A total of 350 TBI patients were enrolled overall in our study. The optimal cutoff point of SIRI was determined at 11.24 × 10⁹/L. After 1:1 PSM, 66 matched pairs (132 patients) were generated. During the 30-day, in-hospital and 365-day follow-up periods, patients with low SIRI level were associated with improved survival (p < 0.05) compared with patients with high SIRI level. Cox regression analysis identified that higher SIRI values was an independent risk factor for all-cause mortality and results were stable on multiple subgroup analyses. Furthermore, ROC analysis indicated that the area under the curve of SIRI [0.6658 (95% Confidence Interval, 0.5630-0.7687)] was greater than that of neutrophils, monocytes, lymphocytes and WBC. The above results were also observed in the matched cohort.

Conclusion: It was suggested that TBI patients with high SIRI level would suffer from a high risk of 30-day, in-hospital and 365-day mortality. SIRI is a promising inflammatory biomarker for predicting TBI patients' prognosis with relatively better predictive power than other single indicators related to peripheral differential leukocyte counts.

Keywords: Medical Information Mart for Intensive Care-IV; all-cause mortality; propensity score matching (PSM); systemic inflammation response index (SIRI); traumatic brain injury (TBI).