AURORA (Leiden D-CAA cohort)

AURORA is a prospective natural history study of Dutch-type hereditary cerebral amyloid angiopathy (D-CAA), an autosomal dominant form of CAA caused by an APP mutation, run at Leiden University Medical Center from 2018. Because carriers can be identified genetically before symptoms, the cohort covers CAA from its presymptomatic phase to recurrent haemorrhage, and it is used to study the order and progression of imaging and fluid biomarkers. The data are not public; papers from the cohort offer them on request from the corresponding author.

Composition

The LUMC study page reports 120 participants. Published analyses included carriers of the causal APP mutation, and people with a symptomatic haemorrhage suspected of CAA plus a first-degree relative with D-CAA. Presymptomatic participants were seen every two years and symptomatic ones yearly. Published subsets: 64 carriers scanned 2018-2021 (mean age 49, 35 women, 35 presymptomatic and 29 with a prior haemorrhage), and 43 carriers with baseline and one-year 3 T scans. AURORA Plus, from August 2021, added PET-CT and further memory tests.

Acquisition

Visits included 3 T MRI on a Philips system, 7 T MRI with visually stimulated BOLD fMRI, blood and CSF sampling and cognitive testing. The 3 T protocol in the 2024 Boston criteria paper had SWI (0.6 x 0.6 x 1.0 mm, 130 slices), 3D FLAIR (1.0 x 1.0 x 0.6 mm) and T2-weighted imaging (3 mm slices). In that subset 19 carriers had no FLAIR.

Annotations

Raters scored CAA markers following STRIVE-2: lobar microbleeds, macrobleeds, cortical superficial siderosis (cSS), convexity subarachnoid haemorrhage, centrum semiovale perivascular spaces and multispot white matter hyperintensities, and applied the Boston criteria v1.5 and v2.0. A separate study made semi-automatic voxel masks of cSS on SWI for 15 D-CAA patients from this cohort (together with 5 sporadic CAA patients from the FOCAS study), drawn twice by one rater and once by a second; repeat masks overlapped with a mean Dice of 0.75.

Known limitations

• No public access route, license or data use terms.
• Single centre and a rare genetic form of CAA; findings may not transfer to sporadic CAA.
• Published counts describe subsets, not the full 120 participants; the sex and age make-up of the whole cohort is not published.
• The vendor of the 7 T system is not stated in the papers used here.