Clinical study on cognitive dysfunction after spontaneous subarachnoid haemorrhage: patient profiles and relationship to cholinergic dysfunction.

Purpose: We aimed to explore the cognitive profiles of subarachnoid haemorrhage patients who returned to the community, along with the associated risk factors.

Methods: We recruited 40 Chinese patients with spontaneous subarachnoid haemorrhage 7-27 months after the initial presentation. They had all been discharged to their homes or to care homes for the elderly. For cognitive assessment, we employed the Cognitive Subscale of the Alzheimer Disease Assessment Scale (ADAS-cog) for global cognitive function, the Frontal Assessment Battery (FAB) for frontal lobe function, and the Rivermead Behavioural Memory Test (RBMT) for everyday memory function.

Results: An ADAS-cog of more than 21/85 (poor global cognitive function) was noted in 14 (35%) patients. A FAB of less than 12/18 (poor frontal lobe function) was noted in 13 (27.5%) patients. An RBMT score of less than 15/26 (poor everyday memory function) was noted in 17 (43.6%) patients. Poor cognitive function was found to be associated with chronic hydrocephalus (in terms of FAB), with clinical vasospasm (in terms of RBMT), and with cerebral infarction (in terms of RBMT).

Conclusions: Poor cognitive function was common and occurred in up to 43.6% of the patients, with the verbal and behavioural memory aspects predominantly affected. We did not find a significant association between cholinergic dysfunction and cognitive dysfunction. Organization of future drug trials and cognitive rehabilitation should take into account the association between frontal lobe dysfunction and chronic hydrocephalus.