gms | German Medical Science

Objective: Delayed cerebral ischemia (DCI) prediction in aneurysmal subarachnoid hemorrhage (aSAH) is still an unsolved mystery, the solution of which could contribute significantly to the individualization and optimization of therapy. Soluble urokinase plasminogen activator receptor (suPAR) is a novel and pivotal inflammatory marker. High suPAR serum levels (suPAR-SL) have been associated with poor outcome in traumatic brain injury and stroke patients, but its importance is unclear in the context of aSAH. We aimed to characterize the role of circulating suPAR in both serum and CSF in aSAH patients.

Methods: All patients between 18 and 90 years of age admitted for aSAH to a tertiary care facility between 2014 and 2019 were screened for eligibility. Demographic data, the occurrence of DCI and clinical outcome (GOSE) were recorded. A healthy control group was included for comparison. suPAR was analyzed on the day of admission (all patients) and on the day of DCI or day 8 in aSAH patients without DCI. One- and two-sample t-tests were used for simple difference comparisons within and between groups. Two regression analyses were constructed to assess the influence of suPAR levels on outcome.

Results: A total of 36 aSAH patients and 32 healthy volunteers were included for analysis. Significantly elevated suPAR serum levels (suPAR-SL) were found for aSAH patients compared to healthy controls (p < .001). In aSAH patients, suPAR-SL increased daily by 4%, while suPAR CSF levels (suPAR-CSFL) showed a significantly faster daily increase by an average of 22.5 % (p = .01). Logistic regression analysis showed significant power in DCI prediction for suPAR-SL at admission (p = .04). Each increase of the suPAR-SL by one ng/ml more than tripled the odds of developing DCI (OR = 3.06). While admission suPAR-CSFL were not predictive of DCI, we observed a significant correlation with the dynamics of deterioration (time between admission and DCI: p = .04): each increase of suPAR-CSFL by one ng/ml accelerated clinical deterioration by almost an entire day. Concerning the outcome, elevated suPAR-SL at admission showed statistical significance for lower GOSE at discharge (p = .04).

Conclusion: We demonstrated that an initial increase in suPAR-SL is associated with the development of DCI and poor outcome. Higher suPAR-CSFL were associated with a more rapid DCI appearance. Biomarkers such as suPAR may help to further clarify the role of inflammation in the context of SAH.