Vasopressin and oxytocin in CSF and plasma of patients with aneurysmal subarachnoid haemorrhage

Abstract

Objective Clinicopathological studies on patients succumbing to subarachnoid haemorrhage (SAH) demonstrated hypothalamic lesions. The implication of the hypothalamic neuropeptides arginine-vasopressin (AVP) and oxytocin (OXT) has not been linked to aneurysmal SAH yet. This study investigates AVP and OXT in CSF and plasma of patients with spontaneous aneurysmal SAH and their association with outcome.Methods CSF and plasma samples of 12 patients with aneurysmal SAH were prospectively studied for 2weeks. AVP and OXT were measured by radioimmunoassay. Outcome was assessed on Glasgow-Outcome-Scale. Twenty-nine patients without neuropsychiatric disturbances served as controls. Differences in neuropeptide concentration time courses were assessed by regression models. Group comparisons were performed by Kruskal-Wallis and correlations by Spearman tests.Results Regression of CSF levels between patients with poor and good outcome revealed significantly lower levels of AVP in patients with poor outcome (p=0.012) while OXT showed a trend towards lower levels (p=0.063). In plasma, no significant differences between outcome groups were found. Group comparisons between poor outcome patients and controls revealed significant differences in CSF for AVP (p=0.001) and OXT (p=0.015). In plasma, AVP yielded significantly different results while OXT did not. No differences were found between the good outcome group and controls. Plasma and CSF concentrations showed no significant correlation.Conclusion Patients with poor outcome after aneurysmal SAH have lower AVP and OXT levels in CSF than patients with good outcome while neuropeptide levels in plasma failed to reflect differences in outcome. The data indicate hypothalamic damage as an aetiologic factor for outcome after aneurysmal SAH.