Expanding the spectrum of cerebral amyloid angiopathy: non-classical symptoms and the emerging iatrogenic subtype

This thesis aimed to identify non-classical symptoms associated with cerebral amyloid angiopathy (CAA) and investigate the disease consequences and burden as experienced by patients and reported by informants.<br>Part I, assessed the frequency and patterns of non-classical symptoms and HRQoL. We found that transient symptoms and headaches occur frequently, but are not associated with specific blood products visible on MRI. Informants of one-third to half of patients reported neuropsychiatric symptoms being present, which was linked to cognitive decline, but not radiological CAA-burden. Further, we found that CAA impacts emotional role functioning and factors related to social participation.<br>Part II investigates iatrogenic CAA (iCAA), a newly identified CAA-subtype. We described the frequency, clinical profile, radiological features and outcome of patients with presumed iCAA, which is thought de be a consequence of specific medical procedures and might be present in 45% of patients with young-onset CAA and in 4% of those fulfilling commonly used diagnostic criteria. Further, we described the first cases of a newly hypothesized transmission mechanism. Finally, we considered and scrutinized the ethical arguments concerning three disclosure-related questions regarding the iatrogenic CAA diagnosis, that arise due to the uncertainty regarding its etiology and prognosis, and the absence of disease-modifying treatments.<br>