Autopsy consent, brain collection, and standardized neuropathologic assessment of ADNI participants: The essential role of the Neuropathology Core

Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO 63110, USA.
Alzheimer's & dementia: the journal of the Alzheimer's Association (Impact Factor: 12.41). 05/2010; 6(3):274-9. DOI: 10.1016/j.jalz.2010.03.012
Source: PubMed

ABSTRACT Our objectives are to facilitate autopsy consent, brain collection, and perform standardized neuropathologic assessments of all Alzheimer's Disease Neuroimaging Initiative (ADNI) participants who come to autopsy at the 58 ADNI sites in the USA and Canada.
Building on the expertise and resources of the existing Alzheimer's Disease Research Center (ADRC) at Washington University School of Medicine, St. Louis, MO, a Neuropathology Core (NPC) to serve ADNI was established with one new highly motivated research coordinator. The ADNI-NPC coordinator provides training materials and protocols to assist clinicians at ADNI sites in obtaining voluntary consent for brain autopsy in ADNI participants. Secondly, the ADNI-NPC maintains a central laboratory to provide uniform neuropathologic assessments using the operational criteria for the classification of AD and other pathologies defined by the National Alzheimer Coordinating Center (NACC). Thirdly, the ADNI-NPC maintains a state-of-the-art brain bank of ADNI-derived brain tissue to promote biomarker and multi-disciplinary clinicopathologic studies.
During the initial year of funding of the ADNI Neuropathology Core, there was notable improvement in the autopsy rate to 44.4%. In the most recent year of funding (September 1(st), 2008 to August 31(st) 2009), our autopsy rate improved to 71.5%. Although the overall numbers to date are small, these data demonstrate that the Neuropathology Core has established the administrative organization with the participating sites to harvest brains from ADNI participants who come to autopsy.
Within two years of operation, the Neuropathology Core has: (1) implemented a protocol to solicit permission for brain autopsy in ADNI participants at all 58 sites who die and (2) to send appropriate brain tissue from the decedents to the Neuropathology Core for a standardized, uniform, and state-of-the-art neuropathologic assessment. The benefit to ADNI of the implementation of the NPC is very clear. Prior to the establishment of the NPC in September 2007, there were 6 deaths but no autopsies in ADNI participants. Subsequent to the establishment of the Core there have been 17 deaths of ADNI participants and 10 autopsies. Hence, the autopsy rate has gone from 0% to 59%. The third major accomplishment is the detection of co-existent pathologies with AD in the autopsied cases. It is possible that these co-morbidities may contribute to any variance in ADNI data.

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Available from: Nigel J. Cairns, Nov 03, 2014
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    • "The ADNI Neuropathology Core (ADNI-NPC) was funded and established at Washington University in St. Louis in September 2007; therefore no autopsies were performed on deceased ADNI subjects prior to this time. Established procedures for obtaining informed consent for autopsy and the autopsy procedures has been previously described [41]. Briefly, participating centers undertake their own brain assessment and provide standard sets of fixed tissue blocks/sections and frozen sections to the ADNI-NPC or send the brain to the ADNI-NPC if the center does not routinely perform neuropathological assessments. "
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    • "While the autopsy numbers at this point are small, to date 10 of our subjects have come to autopsy bearing the clinical diagnosis of either mild cognitive impairment (n = 2) or Alzheimer's dementia (n = 8) at the time of death. Of these, four (40%) had autopsy findings of Alzheimer's pathology without any other significant co-morbidity and six (60%) had autopsy findings of mixed Alzheimer's pathology (Cairns et al., 2010). While subjects with mixed pathology are not addressed by the 'biomarker Figure 3 Hypothetical effects of pure Alzheimer's pathology versus mixed pathology on time-to-progression from mild cognitive impairment to dementia. "
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