Application of the condensed protocol for the NIA-AA guidelines for the neuropathological assessment of Alzheimer's disease in an academic clinical practice

Aims: In response to concerns regarding resource expenditures required to implement fully the 2012 National Institute on Aging and the Alzheimer's Association (NIA-AA) Sponsored Guidelines for the neuropathological assessment of Alzheimer's disease (AD), we previously developed a sensitive and cost-reducing condensed protocol (CP) at the University of Washington (UW) Alzheimer's Disease Research Center (ADRC) that consolidated the recommended NIA-AA protocol into fewer cassettes requiring fewer immunohistochemical stains. The CP was not designed to replace NIA-AA protocols, but instead to make the NIA-AA criteria accessible to clinical and forensic neuropathology practices where resources limit full implementation of NIA-AA guidelines. Methods and results: In this regard, we developed practical criteria to instigate CP sampling and immunostaining, and applied these criteria in an academic clinical neuropathological practice. During the course of 1 year, 73 cases were sampled using the CP; of those, 53 (72.6%) contained histological features that prompted CP work-up. We found that the CP resulted in increased identification of AD and Lewy body disease neuropathological changes from what was expected using a clinical history-driven work-up alone, while saving approximately $900 per case. Conclusions: This study demonstrates the feasibility and cost-savings of the CP applied to a clinical autopsy practice, and highlights potentially unrecognised neurodegenerative disease processes in the general ageing community.