Cognitive outcome after aneurysmal subarachnoid hemorrhage: time course of recovery and relationship to clinical, radiological, and management parameters.

OBJECTIVE: Although many patients show a satisfactory physical outcome after aneurysmal subarachnoid hemorrhage (SAH), disabling cognitive dysfunction may still be present. This study focuses on the time course of cognitive recovery during the first year after aneurysmal SAH, and relates the neuropsychological test results to clinical, radiological, and management parameters.
METHODS: Thirty-two patients were followed prospectively with neuropsychological examinations at 3, 6, and 12 months after SAH. Test results were compared with clinical entry variables, management variables, and pre- and postoperative radiological findings.
RESULTS: The time course of cognitive recovery after aneurysmal SAH is heterogeneous, with motor and psychomotor functions recovering within the first 6 months, whereas verbal memory did not improve significantly until at least 6 months after the ictus. Clinical and radiological parameters reflecting the impact of the bleed were related to memory function, intelligence, and aphasia. The site of aneurysm and mode of treatment could not be linked to neuropsychological outcome. The time length of volume-controlled mechanical ventilation as a reflector of the aggregated consequences of being subjected to an aneurysm rupture correlated with both motor and psychomotor functioning and memory performance, predominantly 6 to 12 months after SAH, but was not linked to intelligence or aphasia.
CONCLUSION: The various cognitive functions have different time courses of recovery, with verbal memory requiring the longest time. Parameters reflecting the impact of the bleed and patient management can be linked to neuropsychological outcome.