Sources of variability in estimates of the prevalence of Alzheimer's disease in the United States.

TitleSources of variability in estimates of the prevalence of Alzheimer's disease in the United States.
Publication TypeJournal Article
Year of Publication2011
AuthorsWilson, RS, Weir, DR, Leurgans, SE, Evans, DA, Hebert, LE, Langa, KM, Plassman, BL, Small, BJ, Bennett, DA
JournalAlzheimers Dement
Volume7
Issue1
Pagination74-9
Date Published2011 Jan
ISSN Number1552-5279
Call Numbernewpubs20110328_Wilson.pdf
KeywordsAged, Aged, 80 and over, Alzheimer disease, Community Health Planning, Comorbidity, Dementia, Diagnosis, Differential, Female, Humans, Incidence, Male, Prevalence, United States
Abstract

<p><b>BACKGROUND: </b>The prevalence of Alzheimer's disease (AD) in the United States was estimated at 2.3 million in 2002 by the Aging, Demographics, and Memory Study (ADAMS), which is almost 50% less than the estimate of 4.5 million in 2000 derived from the Chicago Health and Aging Project.</p><p><b>METHODS: </b>We considered how differences in diagnostic criteria may have contributed to these differences in AD prevalence.</p><p><b>RESULTS: </b>We identified several important differences in diagnostic criteria that may have contributed to the differing estimates of AD prevalence. Two factors were especially noteworthy. First, the Diagnostic and Statistical Manual of Mental Disorders III-R and IV criteria of functional limitation documented by an informant used in ADAMS effectively concentrated the diagnosis of dementia toward a relatively higher level of cognitive impairment. ADAMS separately identified a category of cognitive impairment not dementia and within that group there were a substantial number of cases with "prodromal" AD (a maximum of 1.95 million with upweighting). Second, a substantial proportion of dementia in ADAMS was attributed to either vascular disease (representing a maximum of 0.59 million with upweighting) or undetermined etiology (a maximum of 0.34 million), whereas most dementia, including mixed dementia, was attributed to AD in the Chicago Health and Aging Project.</p><p><b>CONCLUSION: </b>The diagnosis of AD in population studies is a complex process. When a diagnosis of AD excludes persons meeting criteria for vascular dementia, when not all persons with dementia are assigned an etiology, and when a diagnosis of dementia requires an informant report of functional limitations, the prevalence is substantially lower and the diagnosed cases most likely have a relatively higher level of impairment.</p>

URLhttp://mgetit.lib.umich.edu/sfx_local?ctx_enc=info 3Aofi 2Fenc 3AUTF-8;ctx_id=10_1;ctx_tim=2011-03-28T16 3A21 3A52EDT;ctx_ver=Z39.88-2004;rfr_id=info 3Asid 2Fsfxit.com 3Acitation;rft.genre=article;rft_id=info 3Apmid 2F21255745;rft_val_fmt=info 3Aofi 2Ffmt
DOI10.1016/j.jalz.2010.11.006
User Guide Notes

http://www.ncbi.nlm.nih.gov/pubmed/21255745?dopt=Abstract

Endnote Keywords

Epidemiology/Dementia/Alzheimers disease/Vascular dementia/Mild cognitive impairment/Cognitive impairment no dementia

Endnote ID

24590

Alternate JournalAlzheimers Dement
Citation Key7565
PubMed ID21255745
PubMed Central IDPMC3145367
Grant ListR01 AG011101-17 / AG / NIA NIH HHS / United States
R01 AG027010-01 / AG / NIA NIH HHS / United States
U01 AG009740 / AG / NIA NIH HHS / United States
U01 AG009740-21S3 / AG / NIA NIH HHS / United States
R01 AG017917-09 / AG / NIA NIH HHS / United States
R01 AG027010-03 / AG / NIA NIH HHS / United States
U01 AG009740-22 / AG / NIA NIH HHS / United States
R01 AG017917-10 / AG / NIA NIH HHS / United States
R01AG027010 / AG / NIA NIH HHS / United States
R01 AG017917 / AG / NIA NIH HHS / United States
R01AG17917 / AG / NIA NIH HHS / United States
U01 AG009740-21S2 / AG / NIA NIH HHS / United States
R01 AG017917-08 / AG / NIA NIH HHS / United States
U01AG09740 / AG / NIA NIH HHS / United States
R01AG11101 / AG / NIA NIH HHS / United States
R01 AG017917-07 / AG / NIA NIH HHS / United States
R01 AG027010 / AG / NIA NIH HHS / United States
R01 AG011101-15 / AG / NIA NIH HHS / United States
R01 AG027010-02S1 / AG / NIA NIH HHS / United States
U01 AG009740-21S1 / AG / NIA NIH HHS / United States
R01 AG011101 / AG / NIA NIH HHS / United States
R01 AG011101-16 / AG / NIA NIH HHS / United States
R01 AG027010-02 / AG / NIA NIH HHS / United States
R01 AG011101-14 / AG / NIA NIH HHS / United States