MATERIAL and METHODS: This case-control study was performed in Namazi Hospital, affiliated to Shiraz University of Medical Sciences, Shiraz, Iran. The study population included patients referred to Namazi Hospital with a diagnosis of SAH, whose symptoms had emerged within less than 48 hours. The case group consisted of patients with cerebral aneurysms, who were divided into two groups of raptured and un-raptured brain aneurysms. This study examined the relationship between the serum IL-1β levels and brain aneurysms. The number of samples was 43 per group and 86 in total. Forty-eight hours before the onset of symptoms and before surgery, a blood sample was collected to measure the IL-1Β antibody (anti-IL-1β) level; in less than three hours, the serum was isolated and placed in a -80ºC freezer.

RESULTS: In patients with unruptured aneurysms, the Fisher's grade was 0, while most ruptured aneurysms were grade 3. The middle cerebral artery (MCA) (n=10, 23%) was the most common site of aneurysm, followed by the anterior communicating artery (ACom) (n=9, 20%). There was a significant correlation between ruptured aneurysms and the Glasgow Comma Scale (GCS) score (p=0.01) and also Fisher's classification (p=0.04). Patients with ruptured and unruptured aneurysms showed no significant differences regarding the serum IL-1β levels. A significant difference was found in the serum level of IL-1β between the case and control groups (p=0.04).

CONCLUSION: Generally, knowledge of the association between aneurysm development and inflammatory response can have significant clinical implications in the future. The present findings suggested a significant correlation between the IL-1β levels and the outcomes of aneurysmal SAH, independent of initial hemorrhage. Keywords : Neuroinflammation, Aneurysmal subarachnoid hemorrhage, IL-1β