Measuring serum melatonin concentrations to predict clinical outcome after aneurysmal subarachnoid hemorrhage

Oxidative stress has a key role in brain injury and melatonin possesses antioxidant effects. We aimed to ascertain the potential relationship between serum melatonin concentrations and functional outcome following aneurysmal subarachnoid hemorrhage (aSAH).This prospective and observational study was conducted of 169 aSAH patients. Baseline serum melatonin concentrations were determined. A worse 6-month functional outcome was defined as a Glasgow Outcome Scale score of 1-3.Patients with a worse outcome (56 cases) compared to those with a good outcome (113 cases) exhibited significantly higher concentrations of serum melatonin (P 0.001). An area under the receiver operating curve of 0.819 was revealed for the prediction of 6-month worse outcome by serum melatonin concentrations. Multiple logistic regression analysis showed an independent association of serum melatonin concentrations with 6-month worse outcome (odds ratio = 1.204). An intimate correlation existed between serum melatonin concentrations and World Federation of Neurological Surgeons subarachnoid hemorrhage scale scores as well as between serum melatonin concentrations and modified Fisher scores (P 0.001).Patients with higher serum melatonin concentrations are more likely to have a poor prognosis. Serum melatonin can be considered as an independent predictor of functional outcome after aSAH.