Prognostic significance of plasma S1P in acute intracerebral hemorrhage: A prospective cohort study

Objective: Sphingosine-1-phosphate (S1P) may regulate neuroinflammatory immunity and blood-brain barrier integrity. This study was designed to assess the prognostic role of plasma S1P in intracerebral hemorrhage (ICH).Methods: In this prospective cohort study, plasma S1P levels were measured in 51 controls, at admission in 114 ICH patients and at days 1, 3, 5 and 7 in 51 of all patients. Univariate analysis and multivariate analysis were sequentially used to investigate severity correlation and prognosis association.Results: Plasma S1P levels were significantly elevated at admission, peaked at day 5, and declined at day 7, which were significantly higher during 7 days than those of controls (all P < 0.001). Areas under receiver operating characteristic curve (AUCs) of plasma S1P levels insignificant differed among all time points (all P > 0.05). Admission plasma S1P levels, in close correlation with National Institutes of Health Stroke Scale (NIHSS) scores [beta, 7.661; 95 % confidence interval (CI), 4.893-10.399; P < 0.001] and hematoma volume (beta, 1.285; 95 % CI, 0.348-2.230; P < 0.001), independently predicted 3-month poor prognosis (modified Rankin Scale scores of 3-6) (odds ratio, 3.184; 95 % CI, 1.057-9.597; P = 0.040). Admission plasma S1P levels had AUC of 0.799 (95 % CI, 0.713-0.868) for prognosis prediction. The levels > 240.4 ng/ml distinguished risk of poor prognosis with the maximum Youden index of 0.518. Prediction model integrating NIHSS scores, hematoma volume and admission plasma S1P levels had substantially higher prognostic predictive ability than NIHSS scores (P = 0.023), but not than hematoma volume (P = 0.061). Conclusion: There is a significant elevation of plasma S1P levels during early period after ICH, which were independently related to severity and poor prognosis. Thus, plasma S1P may be a potential prognostic biomarker of ICH.