Concentrations of Estradiol, Progesterone and Testosterone in Serum and Cerebrospinal Fluid of Patients with Aneurysmal Subarachnoid Hemorrhage Correlate Weakly with Transcranial Doppler Flow Velocities

Background:The implication of the steroids estradiol, progesterone and testosterone in cerebral vasospasm after aneurysmal subarachnoid hemorrhage (aSAH) has not been comprehensively assessed. In rodents, studies suggested beneficial effects of steroids on cerebral vasospasm after experimental SAH. Studies in humans are warranted, however, a general dilemma of human studies on neuroactive substances is that the brain is not directly accessible and that concentrations in the periphery may not adequately parallel concentrations in the central compartments. In the present study, concentrations of estradiol, progesterone and testosterone in serum and cerebrospinal fluid (CSF) of patients with aSAH were determined. Blood flow velocities in cerebral arteries were measured by transcranial Doppler sonography (TCD). The aim of this study was to evaluate the correlations between the cerebral blood flow velocities and levels of estradiol, progesterone and testosterone in CSF and serum.Results:Samples of serum and CSF of 42 patients with aSAH were collected concomitantly daily or every other day via the arterial line and the external ventricular drainage for two weeks after the hemorrhage. Blood flow velocities in the cerebral arteries were determined by TCD. Total estradiol, progesterone and testosterone concentrations were measured by electro-chemiluminescence immunoassay. The strength of correlation was assessed by Spearman’s rank correlation coefficient. The correlation analysis revealed very weak correlations between cerebral blood flow velocities and concentrations of estradiol, progesterone and testosterone levels in both compartments with correlation coefficients below 0.2.Conclusions:In humans with aSAH, merely very weak correlations between flow velocities of cerebral arteries and concentrations of estradiol, progesterone and testosterone in serum and CSF were demonstrated. The relevance of steroids on cerebral vasospasm in humans remains unclear although beneficial effects were described in rodent studies. Pathways leading to neurological deterioration linked and unlinked to cerebral vasospasm remain complex and possibly interrelated. Thus, the implication of steroids in cerebral vasospasm or other processes of neurological deterioration warrants further clarification.