A thorough systematic-review and meta-analysis was carried-out following PRISMA guidelines. Databases like PubMed, Embase, Cochrane library and Web-of-Science were searched for Randomized Controlled Trials (RCTs) reporting IL-6, TNF-alpha, or CRP levels in the blood or cerebrospinal fluid of the patients who had confirmed aneurysmal Subarachnoid Hemorrhage. Pooled risk ratios (RRs) were calculated using random-effects models and Heterogeneity was assessed using the I² statistic.

Results from 1,742 patients analysed described a vivid pattern certifying that greater levels of inflammation during aSAH saw greater challenges in recovery. Upon investigation of individual biomarkers, 1.IL-6 showed the most pronounced difference between patient groups. 2.TNF-α was also significantly higher in patients with poor outcomes. 3.CRP levels were markedly elevated in those who did not recover as well.

Further, we found that measuring IL-6 directly from the CSF fluid was even better predictor of recovery than measuring it from blood. While the overall trend was clear, there was some natural variation between individual studies, which we attribute to differences in when samples were taken and how recovery was assessed. Finally, our analysis found no signs that these overall results were skewed by unpublished data, giving us more confidence in the findings.

The high levels of inflammatory cytokines i.e. IL-6, TNF-alpha, CRP are linked with worsening functional outcomes after aSAH. Hence, these biomarkers can be used as the prognostic biomarkers for early risk stratification and management of aSAH.