Potential Biomarker to Diagnose Delayed Cerebral Ischemia Among Subarachnoid Hemorrhage Patients: A Systematic Review and Diagnostic Meta-Analysis

Abstract

Determining the diagnosis of Delayed Cerebral Ischemia (DCI) in Subarachnoid Hemorrhage (SAH) patients is currently clinically and radiologically dependent, but it indicates brain ischemia has already occurred and has a poor prognosis. A good biomarker is needed to determine the diagnosis of DCI for faster and more accurate enforcement. A meta-analysis of proportional diagnostic accuracy with PRISMA guidance was conducted. Various databases (PubMed, ScienceDirect, etc) were utilized with the keywords “Delayed Cerebral Ischemia” AND “Biomarker”. We utilized PIROS framework such as Subarachnoid Hemorrhage (Patients), Laboratory Biomarker (Index), DCI Guideline Diagnosis (Reference), Confirmed Delayed Cerebral Ischaemia (Outcome), and Observational OR Validation design(Study). Statistical analysis was run with R Studio (R.4.4.3) [library (mada) and library (meta)] followed by risk of bias assessment using QUADAS 2 independently by each author. A total of 23 out of 203 articles were included. In general, the lab biomarkers had a sensitivity of 75% (95%CI: 69% - 80%) with a specificity of 72% (95%CI: 67% - 76%) and a Diagnostic Odds Ratio of 7.8 (95%CI: 5.7 - 10). Of all the biomarkers included, CSF LDH (Sensitivity 100%, Specificity 76.9%) and CSF Lactate (Sensitivity 83.3%, Specificity 88.9%) had good diagnostic value among others. SROC plot indicates moderate overall diagnostic accuracy, with an average sensitivity and specificity around 73-75%. However, substantial heterogeneity (shown by scattered points and a large predictive region) means individual biomarker performance varies considerably, and new study results may differ significantly from this average. QUADAS-2 analysis showed 95% of the included articles had a low risk of bias. CSF LDH and CSF Lactate show promise as diagnostic biomarkers for early detection of delayed cerebral ischemia (DCI) in subarachnoid hemorrhage (SAH), potentially preventing further brain damage. Laboratory biomarkers are valuable for early DCI detection.