[Current findings on the coincidence of cerebral amyloid angiopathy and Alzheimer's disease].

Cerebral amyloid angiopathy (CAA) is closely related to Alzheimer's disease (AD) despite having distinct pathomechanisms. The CAA modulates cognitive impairment within AD by synergistic effects. The pathophysiologic relations are complex and incompletely understood, possibly due to the heterogeneous nature of CAA with its different subtypes. Both diseases are characterized by a pathologic amyloid metabolism but the pathologic processing of amyloid precursor proteins is distinct. The manifestation of vascular and parenchymal amyloid deposits can either overlap or occur independently and isolated. The investigation of the specific contribution of co-occurring CAA within AD to cognitive deficits requires diagnostic methods that sufficiently identify CAA severity and complexity as well as detailed neuropsychological testing to precisely characterize the cognitive deficits and to draw conclusions regarding their etiology.