The Neuropathology of Older Persons with and Without Dementia from Community versus Clinic Cohorts

Issue title: Mini-Forum: Clinical-Pathologic Correlations in Population- and Community-Based Studies of Brain Aging

Guest editors: Thomas Montine and Joshua Sonnen

Article type: Research Article

Authors: Schneider, Julie A.^{a; b; c; *} | Aggarwal, Neelum T.^{a; b} | Barnes, Lisa^{a; b; d} | Boyle, Patricia^{a; d} | Bennett, David A.^{a; b}

Affiliations: [a] Rush Alzheimer's Disease Center, Chicago, IL, USA | [b] Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA | [c] Department of Pathology, Rush University Medical Center, Chicago, IL, USA | [d] Department of Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA

Correspondence: [*] Corresponding author: Julie A. Schneider, M.D., M.S., Department of Pathology (Neuropathology) and Neurological Sciences, Rush Alzheimer's Disease Center, Rush University Medical Center, Armour Academic Center, 600 South Paulina Street, Suite 1022F, Chicago, IL 60612, USA. Tel.: +1 312 942 2360; Fax: +1 312 942 2297; E-mail: [email protected].

Abstract: Community-based cohorts of older persons may differ neuropathologically from clinic-based cohorts. This study investigated age-related pathologies in persons with and without dementia and included autopsied participants from two community-based cohorts, the Rush Religious Orders Study (n=386) and the Memory and Aging Project (n=195), and one clinic-based cohort, the Clinical Core of the Rush Alzheimer's Disease Center (n=392). Final clinical diagnoses included no cognitive impairment (n=202), mild cognitive impairment (MCI) (n=150), probable Alzheimer's disease (AD) (n=474), possible AD (n=88), and other dementias (n=59). Postmortem diagnoses included pathologic AD, cerebral infarcts, and Lewy body disease. Community-based persons with clinical AD had less severe AD pathology (p<0.001) and had more cerebral infarcts (p<0.001) compared to clinic-based persons. Additionally, community-based persons with MCI had more infarcts compared to clinic-based persons. Overall, there was a higher proportion of Lewy bodies and atypical pathologies in the clinic-based compared to the community-based cohorts (p<0.001). Community-based persons with probable AD show less severe AD pathology and more often have infarcts and mixed pathologies; those with MCI more often have infarcts and mixed pathologies. Overall, clinic-based persons have more Lewy bodies and atypical pathologies. The spectrum of pathologies underlying cognitive impairment in clinic-based cohorts differs from community-based cohorts.

Keywords: Clinic, community, epidemiology, neuropathology, selection bias

DOI: 10.3233/JAD-2009-1227

Journal: Journal of Alzheimer's Disease, vol. 18, no. 3, pp. 691-701, 2009