The Serum Melatonin Levels and Mortality of Patients with Spontaneous Intracerebral Hemorrhage

Objective: Providing melatonin in animal models with spontaneous intracerebral hemorrhage (SIH) has been associated with beneficial effects. However, to our knowledge, there are no published data on circulating melatonin levels regarding the prognosis of SIH patients. Therefore, the objectives of this study were to determine whether serum melatonin levels in SIH patients were associated with early mortality and whether they could be used as prognostic biomarkers. Methods: This observational and prospective study included patients with supratentorial and clinically severe SIH (defined as Glasgow Coma Scale GCS <9) admitted to the Intensive Care Units of six Spanish hospitals. Serum melatonin levels were determined at the time of severe SIH diagnosis. Mortality at 30 days was the study end-point. Results: Non-surviving patients (n = 46) showed higher serum melatonin levels (p < 0.001) than surviving (n = 54) patients. An area under the curve was found for the prediction of 30-day mortality by serum melatonin levels of 0.89 (95% CI = 0.81-0.94; p < 0.001). Multiple logistic regression analysis showed an association of serum melatonin levels with 30-day mortality (Odds Ratio = 8.16; 95% CI = 2.30-28.95; p = 0.001) after controlling for midline shift, glycemia, early evacuation of SIH, and Intracerebral hemorrhage (ICH) score. Conclusions: The novel findings by our study were the presence of higher serum melatonin levels in non-surviving patients than in surviving patients and the association of these levels with mortality.