According to a recently published review of 1800 cases of spontaneous intracerebral hemorrhage (ICH) which were followed over approximately four years, the risk of a ICH recurrence fell by about 25% when systolic blood pressure was maintained below 120mmHG (.75 hazard ration), as compared with blood pressure maintenance in the slightly higher 120-130mmHG range. Our main website: https://amyloidangiopathy.com/ highlights a more detailed 2015 study by some of the same Mass General Hospital researchers. Significantly, there was no difference in either all-cause or vascular mortality–even though mortality was expectedly high at approximately 25% during the four year study.

This research is important because fewer than 50% of patients typically achieve consistent blood pressure control–even though it is one of the few effective means to deal with CAA in particular. Not surprisingly, educational level seems to be a factor limiting successful blood pressure management, which may be related to reduced access to health care based on socio-economic status. It is also worth pointing out that these studies, although directly based only on the occurrence of spontaneous ICH independent of the underlying cause, are also believed to be applicable to ICH when it is caused by cerebral amyloid angiopathy.

It may be worth noting that lower blood pressure has been associated with syncopes (possible leading to dangerous falls), ischemic stroke, or coronary heart disease.
https://www.researchgate.net/publication/365068079_Blood_Pressure_Control_Targets_and_Risk_of_Cardiovascular_and_Cerebrovascular_Events_After_Intracerebral_Hemorrhage