The purpose of this study is to evaluate the predictive value of serum adiponectin levels in aneurysmal subarachnoid hemorrhage patients.

Adiponectin (APN) is an abundant protein hormone derived from adipose tissue. It has been suggested to exert anti-inflammatory, antiatherogenic, and vascular protective. Subarachnoid hemorrhage (SAH) comprises about 5% of all strokes with high mortality and permanent disability rates. Although many patients survive from the initial hemorrhage or rebleeding, they suffered from long-term delayed neurological deficits (DNDs), including stroke, delayed cerebral ischemia, cognitive and neuropsychological abnormalities that seriously impact overall function and quality of life. Ruptured cerebral aneurysms are the most common cause of SAH. There is growing evidence supporting APN act as a predictive factor for SAH. The observational study will focus on the predictive value of serum adiponectin levels in aneurysmal subarachnoid hemorrhage (aSAH).

Inclusion Criteria:

• Age>18yrs and age<90yrs
• It shows subarachnoid hemorrhage (SAH) based on computed tomography (CT) scan on admission
• Aneurysmal subarachnoid hemorrhage confirmed by computed tomography angiography (CTA), magnetic resonance angiography (MRA) or digital subtraction angiography (DSA)
• SAH grade is assessed by Hunt & Hess classification
• Informed consented

Exclusion Criteria:

• Traumatic subarachnoid hemorrhage
• Patients with cerebral herniation or highly possible to occur within 2 days from SAH
• Length of hospital stay is expected to be less than 5 days
• Duration from onset to admission is more than 48 hours
• Disturbance of communication or poor compliance to blood collection, imaging examination and follow-up

Patients with aneurysmal subarachnoid hemorrhage who are hospitalized within 24 hours from onset.