OBJECTIVES: To investigate the prevalence of coincident anticoagulation in patients with cognitive disorders and possible or probable cerebral amyloid angiopathy (CAA) as well as the relationship between the presence of oral anticoagulation and CAA-specific lesion load.

MATERIALS AND METHODS: Patients with subjective cognitive decline (SCD), amnestic and non-amnestic mild cognitive impairment (aMCI/naMCI), Alzheimer's disease (AD), mixed dementia (MD) and vascular dementia (VD) who presented to our outpatient dementia clinic between February 2016 and October 2020 were included in this retrospective analysis. Patients underwent cranial magnetic resonance imaging (MRI). MRI data sets were analyzed regarding the presence of CAA-related MRI biomarkers to determine CAA prevalence. Presence of anticoagulant therapy was determined by chart review.

RESULTS: Within the study period, 458 patients (209 male, 249 female, mean age 73.2 ± 9.9 years) with SCD (n = 44), naMCI (n = 40), aMCI (n = 182), AD (n = 120), MD (n = 68) and VD (n = 4) were analyzed. A total of 109 patients (23.8%) were diagnosed with possible or probable CAA. CAA prevalence was highest in aMCI (39.4%) and MD (28.4%). Of patients with possible or probable CAA, 30.3% were under platelet aggregation inhibition, 12.8% were treated with novel oral anticoagulants and 3.7% received phenprocoumon treatment. Regarding the whole study cohort, patients under oral anticoagulation showed more cerebral microbleeds (p = 0.047). There was no relationship between oral anticoagulation therapy and the frequency of cortical superficial siderosis (p = 0.634).

CONCLUSION: CAA is a frequent phenomenon in older patients with cognitive disorders. Almost half of CAA patients receive anticoagulant therapy. Oral anticoagulation is associated with a higher number of cortical and subcortical microbleeds.