Background and rationale:~Delayed cerebral ischemia (DCI) is the independent most important predictor of neurological disability in survivors following aneurysmal subarachnoid hemorrhage (aSAH). DCI could also be identified as the most important predictor of moderate to severe neuropsychological impairment following aSAH. Only few prospective studies so far specifically analyzed the effect size of the relationship between DCI and neuropsychological impairment, and all studies had a methodological weakness: lack of a baseline neuropsychological assessment before the onset of DCI.~In studies analyzing the neuropsychological outcome after aSAH, the Montreal Cognitive Assessment (MoCA) is the most comprehensive, sensitive and specific instrument among the short tests. The MoCA is increasingly used in the aSAH population, while its validity and reliability has only been demonstrated in the normal population or patients suffering from diseases different from aSAH, such as e.g. Parkinson's disease or dementia. Today, neuropsychological examinations find entry into clinical routine for aSAH patients to estimate the need for inpatient rehabilitation. However, the MoCA is often applied to aSAH patients in a busy intensive or intermediate care unit, while it remains largely unknown whether the distraction in such an environment represents a bias to the obtained results.~This study therefore evaluates aSAH patients before and after the phase of DCI, as well as three months after aSAH, in order to estimate the impact of DCI on neuropsychological impairment. In addition, the extent and location of cerebral ischemia, as measured with the Alberta Stroke Program Early CT Score (ASPECTS) is correlated with the neuropsychological outcome.~Furthermore, the study measures the test/retest reliability of the MoCA, as well as the influence of the intensive care environment on the MoCA results in a randomized fashion in subjects with acute brain damage (and no aSAH).~Objectives:~The primary objective of this multicenter observational study is to determine the effect size of the relationship between DCI and neuropsychological impairment 14-28 days and 3 months after aSAH.~Secondary objectives are the feasibility to administer and the validity of the MoCA in an intensive care unit setting, as well as the test/retest reliability of the MoCA in patients with acute brain damage in absence of aSAH.~Outcomes:~The primary endpoint is the proportion of patients with or without DCI that show worsening on the MoCA 3 months after the ictus as compared to before the DCI phase by at least two points.~Key secondary endpoints for part 1 of the study are:~The proportion of patients with or without DCI that show worsening on the MoCA 14-28 days after the ictus as compared to before the DCI phase by at least two points.~The absolute difference of the MoCA before and after the active phase of DCI in patients with versus without DCI.~The absolute difference of the MoCA before the active phase of DCI and 3 months after aSAH in patients with versus without DCI~The rate of patients with versus without DCI that show cognitive impairment at 14-28 days and 3 months (defined as MoCA < 26 points)~The correlation of neuropsychological outcome with the extent and location of ischemic lesions on brain CT-scan 12-21 days post-SAH, graded by the semi-quantitative ASPECT-grading~Health-related quality of life at 3 months in patients with versus without DCI~Home-time at 3 months in patients with versus without DCI~Death and dependency at 3 months in patients with versus without DCI~The absolute MoCA result, health-related quality of life and home-time at 3 months in patients with versus without hydrocephalus requiring shunting~The absolute MoCA result, health-related quality of life and home-time at 3 months in patients with surgical versus endovascular aneurysm occlusion~Key secondary endpoints for part 2 of the study are:~The test/retest reliability of the MoCA in patients with acute brain damage~The influence of the intensive care environment on the MoCA in patients with acute brain damage
The primary objective of this multicenter observational study is to determine the effect size of the relationship between DCI and neuropsychological impairment 14-28 days and 3 months after aSAH.~Secondary objectives are the feasibility to administer and the validity of the MoCA in an intensive care unit setting, as well as the test/retest reliability of the MoCA in patients with acute brain damage in absence of aSAH.