Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT06128824 |
Other study ID # |
HIFI-CAA-01 |
Secondary ID |
|
Status |
Recruiting |
Phase |
|
First received |
|
Last updated |
|
Start date |
March 19, 2019 |
Est. completion date |
March 31, 2026 |
Study information
Verified date |
November 2023 |
Source |
Ludwig-Maximilians - University of Munich |
Contact |
Martin Dichgans, MD |
Phone |
+49 89 4400 |
Email |
martin.dichgans[@]med.uni-muenchen.de |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
Cerebral amyloid angiopathy (CAA), caused by amyloid beta depositions in the walls of small
cerebral vessels, is remarkably common in the elderly. Its major clinical consequences
include intracerebral hemorrhages (ICH) typically in lobar location, functional dependence
(disability) and cognitive impairment.
Cortical superficial siderosis (cSS) is a common finding in CAA patients and can even be the
only magnetic resonance imaging sign of CAA. cSS is of high prognostic relevance regarding
future intracerebral haemorrhage and disability. Previous studies suggest that cSS is caused
by recurrent focal subarachnoid hemorrhages (fSAH). However, the exact mechanisms and the
temporal dynamics of this highly relevant imaging finding are largely unknown.
In addition to hemorrhagic manifestations, such as cSS, CAA patients also show ischemic
lesions. Of particular interest are acute ischemic lesions as detected by diffusion imaging,
which seem to be highly prevalent. Since haemorrhagic and ischemic lesions require
fundamentally different therapeutic strategies, understanding the relevance and interplay of
both lesion types is highly important for clinical decision making.
The HIFI-CAA cohort study aims to provide novel insights into cSS, acute ischemic lesions and
other relevant brain alterations in CAA through high-frequency (monthly) serial magnetic
resonance imaging.
Description:
Cerebral amyloid angiopathy (CAA) is defined as the deposition of β-amyloid in the walls of
small cortical cerebral vessels. It is very common in the elderly population with prevalence
rates up to 60% and is associated with Alzheimer´s disease. Intracerebral lobar
macrohemorrhages (ICH) are the most devastating presentation of CAA and the main cause of
morbidity and mortality. In addition to developing clinically manifest strokes, CAA patients
may also suffer from transient neurological symptoms and progressive cognitive impairment
ultimately resulting in dementia.
Apart from ICH, typical MRI signs of CAA include multiple cerebral microbleeds (CMB) in a
cortical-subcortical localization, white matter hyperintensities on T2-weighted images and
supratentorial cortical superficial siderosis (cSS). Main risk factors for recurrence of
CAA-related ICH are apolipoprotein E ε2 or ε4 alleles, previous ICHs and CMB on follow-up
imaging. Recently, cSS emerged as an additional, major independent risk factor for ICH and
disability.
In CAA, siderosis affects the convexity of the cerebral hemispheres, and thus is termed
cortical superficial siderosis (cSS). This is in contrast to infratentorial superficial
siderosis, which is not linked to CAA. CSS is likely caused by recurrent non-traumatic, focal
convexity subarachnoid hemorrhages (fSAH). There are causes of fSAH and cSS other than CAA,
and these causes seem to vary depending on age: in younger patients (< 60 years of age) fSAH
and cSS are most commonly seen in the context of trauma, vasculitis and reversible cerebral
vasoconstriction syndrome, while CAA seems to be the by far most common cause in subjects
above 60 years of age. cSS is common (> 60%) in patients with histologically proven CAA, and
may be the only hemorrhagic imaging sign on MRI.
Lesions on diffusion-weighted imaging, i.e. areas of restricted diffusion, are a very
frequent finding in CAA. These diffusion restrictions can be found in 25% to 50% of CAA
patients when performing a single MRI. One recent study even suggests a spatial relationship
with cSS. The clinical significance of these lesions is not yet fully established. The most
likely pathophysiology behind these lesions is acute ischemia, or to be more precise
cytotoxic edema after brain ischemia/infarction. However, subcortical infarcts as detected
through a diffusion-restricted lesion can have vastly different fates, ranging from
disappearance to complete brain tissue loss (cavitation). An important step in the
understanding of these lesions is the precise estimation of prevalence and tissue
consequences. A critical point in this endeavour is that these diffusion restricted lesions
are typically only visible for a few weeks. Thus, they can remain completely undetected in
studies using conventional study designs with follow-up intervals as long as 6 months, one
year or even longer.
While small subcortical and cortical ischemic lesions (detectable as diffusion restrictions)
are a common finding in CAA patients, their exact prevalence and relevance for disease
progression are unclear. Overall, temporal dynamics of the processes leading to hemorrhagic
and ischemic manifestations of CAA as well as their interrelationships are insufficiently
understood. These critical aspects can be addressed by a novel study design with serial,
monthly magnetic resonance imaging. The study design is inspired by a recent high-frequency
serial imaging study in patients with sporadic, non-amyloid cerebral small vessel disease
conducted at Nijmegen (Radboud University Nijmegen Diffusion tensor and Magnetic resonance
imaging Cohort - Investigating The origin and Evolution of cerebral small vessel disease, RUN
DMC - InTENse).
The primary aim of this study is to prospectively evaluate the development and temporal
evolution of incident and prevalent fSAH & cSS in CAA patients.
Secondary aims are i) to assess the monthly incidence of acute ischemic lesions (diffusion
restrictions) in CAA patients with cSS/fSAH and to compare the incidence with lobar ICH
survivors, and ii) to assess the inter-relationship between hemorrhagic lesions
(fSAH/cSS/CMB) and acute ischemic lesions as well as the association between these lesions
and cerebrovascular event rates and functional status.