Temporal and Spatial Clustering of Intracerebral Hemorrhage in Cerebral Amyloid Angiopathy.

OBJECTIVES: Cerebral amyloid angiopathy (CAA)-associated lobar intracerebral hemorrhage (ICH) has a high risk of recurrence, but the underlying mechanisms remain uncertain. We, therefore, aimed to characterize patterns of recurrent ICH. METHODS: We investigated early recurrent ICH (≥1 recurrent ICH event within 90 days of the index event) and ICH clusters (≥2 ICH events within 90 days at any time point) in 2 large cohorts of consecutive patients with first-ever ICH and available MRI. RESULTS: In 682 included patients (median age 68 years, 40.3% female, median follow-up time 4.1 years), 18 (2.6%) had an early recurrent ICH, which was associated with higher age and CAA. In patients with probable CAA, the risk of early recurrent ICH was increased 5-fold within the first 3 months compared with during months 4-12 (hazard ratio 5.41, 95% CI 2.18-13.4) while no significant difference was observed in patients without CAA. In patients with an ICH cluster, we observed spatial clustering (recurrent ICH within close proximity of index ICH in 63.0%) and a tendency for multiple sequential hemorrhages (≥3 ICH foci within 3 months in 44.4%). DISCUSSION: Our data provide evidence of both temporal and spatial clustering of ICH in CAA, suggesting a transient and localized active bleeding-prone process.

Iatrogenic cerebral amyloid angiopathy in older adults.

BACKGROUND AND PURPOSE: An increasing number of cases of iatrogenic cerebral amyloid angiopathy (CAA) have now been reported worldwide. Proposed diagnostic criteria require a history of medical intervention with potential for amyloid-ß transmission, for example those using cadaveric dura mater or requiring instrumentation of the brain or spinal cord. Clinical presentation occurs after an appropriate latency (usually three or four decades); to date, most patients with iatrogenic CAA have had 'early-onset' disease (compared to sporadic, age-related, CAA), as a consequence of childhood procedures. RESULTS: We describe five cases of possible iatrogenic CAA in adults presenting in later life (aged 65 years and older); all had prior neurosurgical interventions and presented after a latency suggestive of iatrogenic disease (range 30-39 years). Use of cadaveric dura mater was confirmed in one case, and highly likely in the remainder. CONCLUSION: The presentation of iatrogenic CAA in older adults widens the known potential spectrum of this disease and highlights the difficulties of making the diagnosis in this age group, and particularly in differentiating iatrogenic from sporadic CAA. Increased vigilance for cases presenting at an older age is essential for furthering our understanding of the clinical phenotype and broader implications of iatrogenic CAA.