Cortical subarachnoid haemorrhage in the elderly: a recurrent event probably related to cerebral amyloid angiopathy

Objective: Isolated, non-traumatic, cortical subarachnoid haemorrhage (cSAH) is a rare type of cerebrovascular disease caused by various disorders. In a few cases, especially in the elderly, no apparent cause can be identified. We report a case series of patients without apparent cause of cSAH. We aimed to determine whether cerebral amyloid angiopathy (CAA) could be a common cause of cSAH.

Methods: We retrospectively analysed clinical and radiological data of consecutive patients admitted to a tertiary stroke unit with cSAH. All patients had brain MRI as a part of their initial evaluation and a repeat examination during follow-up.

Results: Amongst 25 patients with cSAH, 10 patients had no apparent cause of cSAH (six men and four women; mean age ± SD: 73.8 ± 8.5 years). All patients with no apparent cause presented with single or recurrent focal transient neurological symptoms of short duration. Only one patient experienced headache. cSAH was limited to one or two sulci, mostly the central sulcus. MRI showed the evidence of prior asymptomatic bleeding in 9/10 patients: cortical hemosiderosis (9/10), lobar intracerebral haemorrhage (ICH) (6/10) and cortical microbleeds (9/10). Eight of ten patients met the Boston criteria for probable CAA and 2/10 for possible CAA. During follow-up, three patients had recurrent bleeding: cSAH (2) and lobar ICH (1).

Conclusions: Our findings suggest that CAA could be a common cause of cSAH in the elderly with a fairly uniform clinical presentation. In addition to prior cortical bleeding (ICH, MBs), most patients from the present series had evidence of focal cortical hemosiderosis likely corresponding with prior unrecognized cSAH and suggesting that cSAH was a recurrent event.