Article

Focal hemosiderin deposits and β-amyloid load in the ADNI cohort.

Department of Radiology, Mayo Clinic, Rochester, MN, USA. Electronic address: .
Alzheimer's & dementia: the journal of the Alzheimer's Association (Impact Factor: 14.48). 01/2013; DOI: 10.1016/j.jalz.2012.10.011
Source: PubMed

ABSTRACT BACKGROUND: Prevalence and risk factors for focal hemosiderin deposits are important considerations when planning amyloid-modifying trials for treatment and prevention of Alzheimer's disease (AD). METHODS: Subjects were cognitively normal (n = 171), early-mild cognitive impairment (MCI) (n = 240), late-MCI (n = 111), and AD (n = 40) from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Microhemorrhages and superficial siderosis were assessed at baseline and on all available MRIs at 3, 6, and 12 months. β-amyloid load was assessed with (18)F-florbetapir positron emission tomography. RESULTS: Prevalence of superficial siderosis was 1% and prevalence of microhemorrhages was 25% increasing with age (P < .001) and β-amyloid load (P < .001). Topographic densities of microhemorrhages were highest in the occipital lobes and lowest in the deep/infratentorial regions. A greater number of microhemorrhages at baseline was associated with a greater annualized rate of additional microhemorrhages by last follow-up (rank correlation = 0.49; P < .001). CONCLUSIONS: Focal hemosiderin deposits are relatively common in the ADNI cohort and are associated with β-amyloid load.

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