Spatial and temporal intracerebral hemorrhage patterns in Dutch-type hereditary cerebral amyloid angiopathy

Location and Timing of Recurrent, Nontraumatic Intracerebral Hemorrhage

Importance

: The spatial and temporal distribution of intracerebral hemorrhage (ICH) recurrence are largely unknown.

Objective

To assess timing and location of recurrent ICH events in relation to the index ICH event (adjacent ICH [adjICH] vs remote ICH [remICH]).

Design, Setting, and Participants

This cohort study was a pooled analysis of individual cohort studies from 2002 to 2021 among hospital-based European cohorts. Patients with 2 or more clinically distinguishable (≥1 recurrent) small vessel disease-related ICH events were included. Data analysis was performed from December 2023 to December 2024.

Exposures

ICH location and underlying small vessel disease type.

Main Outcomes and Measures

The primary outcome was adjICH, defined by anatomical ICH location and side, and the secondary outcome was time to recurrence. Multivariable regression analyses were conducted adjusting for ICH location, cerebral amyloid angiopathy according to Boston 2.0 or simplified Edinburgh criteria, convexity subarachnoid hemorrhage extension, hypertension, and antihypertensive treatment, including an interaction term for hypertension and antihypertensive treatment.

Results

Among 733 patients (median [IQR] age, 72.4 [65.2 to 79.0] years; 346 female [47.2%]), there were 1616 ICH events, including 733 index and 883 recurrent ICH events (range, 1 to 6 recurrences) over a median (IQR) follow-up of 2.53 (0.66 to 4.92) years. There were 340 patients (46.4%) with adjICH and 393 patients (53.6%) with remICH. Among recurrent ICH events, there were 476 adjICH events and 407 remICH events. In multivariable regression analyses, lobar index ICH (adjusted odds ratio [aOR], 2.08; 95% CI, 1.32 to 3.27) and cerebral amyloid angiopathy at index ICH (aOR, 2.21; 95% CI, 1.57 to 3.11) were associated with higher odds of adjICH, while cerebellar index ICH was associated with lower odds of adjICH (aOR, 0.25; 95% CI, 0.07 to 0.89). The median (IQR) time to recurrence was 1.25 (0.36 to 3.38) years for adjICH and 2.21 (0.66 to 4.85) years for remICH. Previous lobar or convexity subarachnoid hemorrhage (coefficient, -0.75; 95% CI, -1.25 to -0.25; P = .003 ), adjICH (coefficient, -0.60; 95% CI, -1.02 to -0.18; P = .005), and the number of previous ICH events (coefficient per 1-event increase, -0.62; 95% CI, -0.93 to -0.32; P < .001) were independently associated with a shorter time to recurrence.

Conclusions and relevance

This study found that early recurrence and cerebral amyloid angiopathy were associated with adjICH. These findings suggest that regional, tissue-based factors may facilitate recurrence and that identifying and targeting local vasculopathic changes may represent potential novel treatment targets.

The Impact of Vascular Risk Factors on Cerebral Amyloid Angiopathy: A Cohort Study in Hereditary Cerebral Amyloid Angiopathy and a Systemic Review in Sporadic Cerebral Amyloid Angiopathy

INTRODUCTION

Cerebral amyloid angiopathy (CAA) has a remarkably variable disease course, even in monogenetic hereditary forms. Our aim was to investigate the prevalence of vascular risk factors and their effect on disease onset and course in Dutch-type hereditary (D-)CAA and sporadic CAA.

METHODS

We performed a cohort study in D-CAA to investigate the association between vascular risk factors (hypertension, hypercholesterolemia, smoking, and alcohol use) and age of intracerebral hemorrhage (ICH) onset and time of ICH recurrence with survival analyses. In addition, we performed a systematic review to assess the prevalence of vascular risk factors and their effect on clinical outcome in sporadic CAA. We searched PubMed, Embase, Web of Science, and Cochrane Library from 1987 to 2022 and included cohorts with ≥10 patients. We created forest plots, calculated pooled estimates, and reported variability (heterogeneity plus sampling variability) and risk of bias.

RESULTS

We included 70 participants with D-CAA (47% women, mean age 53 years). Sixteen (23%) had hypertension, 15 (21%) had hypercholesterolemia, 45 (64%) were smokers, and 61 (87%) used alcohol. We found no clear effect of vascular risk factors on age of first ICH (log-rank test hypertension: p = 0.35, hypercholesterolemia: p = 0.41, smoking: p = 0.61, and alcohol use: p = 0.55) or time until ICH recurrence (log-rank test hypertension: p = 0.71, hypercholesterolemia: p = 0.20, and smoking: p = 0.71). We identified 25 out of 1,234 screened papers that assessed the prevalence of risk factors in CAA and 6 that reported clinical outcomes. The pooled prevalence estimates of hypertension was 62% (95% CI: 55-69%), diabetes was 17% (95% CI: 14-20%), dyslipidemia was 32% (95% CI: 23-41%), and tobacco use was 27% (95% CI: 18-36%). One study reported study diabetes and hypertension to be associated with a lower risk of recurrent ICH, whereas another study reported hypertension to be associated with an increased risk. All other studies showed no association between vascular risk factors and clinical outcome. High-quality studies focusing on vascular risk factors were lacking.

CONCLUSION

In patients with D-CAA and sporadic CAA, the prevalence of vascular risk factors is high. Although this suggests an opportunity for prevention, there is no clear association between these risk factors and CAA-related ICH onset and recurrence.

Temporal Ordering of Biomarkers in Dutch-Type Hereditary Cerebral Amyloid Angiopathy

BACKGROUND

The temporal ordering of biomarkers for cerebral amyloid angiopathy (CAA) is important for their use in trials and for the understanding of the pathological cascade of CAA. We investigated the presence and abnormality of the most common biomarkers in the largest (pre)symptomatic Dutch-type hereditary CAA (D-CAA) cohort to date.

METHODS

We included cross-sectional data from participants with (pre)symptomatic D-CAA and controls without CAA. We investigated CAA-related cerebral small vessel disease markers on 3T-MRI, cerebrovascular reactivity with functional 7T-MRI (fMRI) and amyloid-β40 and amyloid-β42 levels in cerebrospinal fluid. We calculated frequencies and plotted biomarker abnormality according to age to form scatterplots.

RESULTS

We included 68 participants with D-CAA (59% presymptomatic, mean age, 50 [range, 26-75] years; 53% women), 53 controls (mean age, 51 years; 42% women) for cerebrospinal fluid analysis and 36 controls (mean age, 53 years; 100% women) for fMRI analysis. Decreased cerebrospinal fluid amyloid-β40 and amyloid-β42 levels were the earliest biomarkers present: all D-CAA participants had lower levels of amyloid-β40 and amyloid-β42 compared with controls (youngest participant 30 years). Markers of nonhemorrhagic injury (>20 enlarged perivascular spaces in the centrum semiovale and white matter hyperintensities Fazekas score, ≥2, present in 83% [n=54]) and markers of impaired cerebrovascular reactivity (abnormal BOLD amplitude, time to peak and time to baseline, present in 56% [n=38]) were present from the age of 30 years. Finally, markers of hemorrhagic injury were present in 64% (n=41) and only appeared after the age of 41 years (first microbleeds and macrobleeds followed by cortical superficial siderosis).

CONCLUSIONS

Our results suggest that amyloid biomarkers in cerebrospinal fluid are the first to become abnormal in CAA, followed by MRI biomarkers for cerebrovascular reactivity and nonhemorrhagic injury and lastly hemorrhagic injury. This temporal ordering probably reflects the pathological stages of CAA and should be taken into account when future therapeutic trials targeting specific stages are designed.

Progressive White Matter Injury in Preclinical Dutch Cerebral Amyloid Angiopathy

Autosomal-dominant, Dutch-type cerebral amyloid angiopathy (D-CAA) offers a unique opportunity to develop biomarkers for pre-symptomatic cerebral amyloid angiopathy (CAA). We hypothesized that neuroimaging measures of white matter injury would be present and progressive in D-CAA prior to hemorrhagic lesions or symptomatic hemorrhage. In a longitudinal cohort of D-CAA carriers and non-carriers, we observed divergence of white matter injury measures between D-CAA carriers and non-carriers prior to the appearance of cerebral microbleeds and >14 years before the average age of first symptomatic hemorrhage. These results indicate that white matter disruption measures may be valuable cross-sectional and longitudinal biomarkers of D-CAA progression. ANN NEUROL 2022;92:358-363.