Original Article

Increased Prevalence in Alzheimer Disease in the Northeast Tennessee Region of the United States

Authors: Sylvester O. Orimaye, PhD, MPH, Jodi L. Southerland, DrPh, Adekunle O. Oke, MD, MPH, Aderonke Ajibade, MD, MPH


Objectives: This study describes the changes in prevalence odds ratios (PORs) for Alzheimer disease (AD) in the northeast Tennessee region (NTR) during a 3-year period, describes the statistical assessment process, and critically assesses the database from which the statistical association was derived. The article also examines several beliefs pertinent to the clinical management of AD in the NTR from the perspective of professionals delivering services.

Methods: We extracted prevalence data for NTR counties for 2013, 2014, and 2015 from the Centers for Medicare & Medicaid Services Geographic Variation Public Use File. We used the crude prevalence and the 2010 US Census Data fixed population for each county to compute the POR. The 2013 Economic Research Service Rural-Urban Continuum Codes were used to identify rural and urban counties in the NTR. We collected primary data on the perceived observation of the increasing prevalence in the NTR during the last 3 years and barriers to early diagnosis through an online survey from 44 experts and professionals working in AD-related fields within the NTR.

Results: The PORs of AD in rural counties in NTR increased by 18.3%, 4.7%, and 19% compared with urban counties for 2013, 2014, and 2015, respectively. The POR of AD for the entire NTR region increased by 22.7%, 22.5%, and 21.2% compared with other regions in Tennessee for 2013, 2014, and 2015, respectively. Compared with 2012, 68.4% of respondents currently work with more individuals with AD; 71.8% reported that the NTR has a higher number of late-stage diagnoses of AD. A total of 92.3% strongly agreed that early detection of AD is important, and 95% agreed that early diagnosis could prolong the lives of patients with AD; 51.2% were unaware of existing AD screening services. Reported barriers were denial, lack of patient awareness, inefficient screening methods, communication, and lack of community resources.

Conclusions: Increased prevalence of AD among inhabitants in the NTR and identified barriers to early screening or diagnosis in the management of AD were identified. Access to early screening techniques must be prioritized in deprived areas within the NTR. Healthcare providers and medical professionals in the NTR must be well equipped with the required training and resources to respond adequately to the increasing prevalence of AD.
Posted in: Neurology16

This content is limited to qualifying members.

Existing members, please login first.

If you have an existing account please login now to access this article or view your purchase options.

Purchase only this article ($15)

Create a free account, then purchase this article to download or access it online for 24 hours.

Purchase an SMJ online subscription ($75)

Create a free account, then purchase a subscription to get complete access to all articles for a full year.

Purchase a membership plan (fees vary)

Premium members can access all articles plus recieve many more benefits. View all membership plans and benefit packages.


1. Abner EL, Jicha GA, Christian WJ, et al. Rural-urban differences in Alzheimer’s disease and related disorders diagnostic prevalence in Kentucky and West Virginia. J Rural Health 2016;32:314-320.
2. Hebert LE, Weuve J, Scherr PA, et al. Alzheimer disease in the United States (2010-2050) estimated using the 2010 Census. Neurology 2013;80:1778-1783.
3. Mattos MK, Snitz BE, Lingler JH, et al. Older rural-and urban-dwelling Appalachian adults with mild cognitive impairment. J Rural Health 2017;33:208-216.
4. Taylor CA, Greenlund SF, McGuire LC, et al. Deaths from Alzheimer’s disease-United States, 1999-2014. MMWR Morb Mortal Wkly Rep 2017;66:521.
5. Thompson ML, Myers JE, Kriebel D. Prevalence odds ratio or prevalence ratio in the analysis of cross sectional data: what is to be done? Occup Environ Med 1998;55:272-277.
6. Furiak NM, Klein RW, Kahle-Wrobleski K, et al. Modeling screening, prevention, and delaying of Alzheimer’s disease: an early-stage decision analytic model. BMC Med Inform Decis Mak 2010;10:24.
7. Pearce N. Effect measures in prevalence studies. Environ Health Perspect 2004;112:1047-1050.
8. Vos SJB, Verhey F, Frölich L, et al. Prevalence and prognosis of Alzheimer’s disease at the mild cognitive impairment stage. Brain 2015;138:1327-1338.
9. Mehta KM, Yeo GW. Systematic review of dementia prevalence and incidence in United States race/ethnic populations. Alzheimers Dement 2017;13:72-83.
10. Centers for Medicare & Medicaid. Medicare data for the geographic variation public use file: a methodological overview. https://www.cms.gov/Research-Statistics-Data-and-Systems/Statistics-Trends-and-Reports/Medicare-Geographic-Variation/Downloads/Geo_Var_PUF_Methods_Paper.pdf. Updated February 2020. Accessed May 2, 2020.
11. Ward MM. Estimating disease prevalence and incidence using administrative data: some assembly required. J Rheumatol 2013;40:1241-1243.
12. Ratcliffe M, Burd C, Holder K, et al. Defining rural at the US Census Bureau. American community survey and geography brief. https://www2.census.gov/geo/pdfs/reference/ua/Defining_Rural.pdf. Published December 2016. Accessed May 2, 2020.
13. Ingram DD, Franco SJ. NCHS urban-rural classification scheme for counties. Vital Health Stat 2 2012;(154):1-65.
14. Pizur-Barnekow K, Muusz M, McKenna C, et al. Service coordinators’ perceptions of autism-specific screening and referral practices in early intervention. Topics Early Child Spec Educ 2013;33:153-161.
15. James LW, Pizur-Barnekow KA, Schefkind S. Online survey examining practitioners’ perceived preparedness in the early identification of autism. Am J Occup Ther 2014;68:e13-e20.
16. Eichler T, Thyrian JR, Hertel J, et al. Rates of formal diagnosis of dementia in primary care: the effect of screening. Alzheimer’s Dement (Amst) 2015;1:87-93.
17. Jack CR, Therneau TM, Weigand SD, et al. Prevalence of biologically vs clinically defined Alzheimer spectrum entities using the National Institute on Aging-Alzheimer’s Association research framework. JAMA Neurol 2019;76:1174-1183.
18. Orimaye SO, Wong JS-M, Wong CP. Deep language space neural network for classifying mild cognitive impairment and Alzheimer-type dementia. PLoS One 2018;13(11).
19. Orimaye SO, Wong JSM, Golden KJ, et al. Predicting probable Alzheimer’s disease using linguistic deficits and biomarkers. BMC Bioinformatics 2017;18:34.
20. Pollard K, Jacobsen LA. The Appalachian region in 2010: a census data overview chartbook. https://www.arc.gov/assets/research_reports/AppalachianRegion2010CensusReport1.pdf. Published September 2011. Accessed May 2, 2020.
21. Kirson NY, Meadows ES, Desai U, et al. Temporal and geographic variation in the incidence of Alzheimer’s disease diagnosis in the US between 2007 and 2014. J Am Geriatr Soc 2019;68:346-353.
22. Amariglio RE, Donohue MC, Marshall GA, et al. Tracking early decline in cognitive function in older individuals at risk for Alzheimer disease dementia: the Alzheimer’s Disease Cooperative Study Cognitive Function Instrument. JAMA Neurol 2015;72:446-454.
23. Zissimopoulos JM, Tysinger BC, St Clair PA, et al. The impact of changes in population health and mortality on future prevalence of Alzheimer’s disease and other dementias in the United States. J Gerontol B Psychol Sci Soc Sci 2018;73(suppl 1):S38-S47.
24. Phillips J, Pond CD, Paterson NE, et al. Difficulties in disclosing the diagnosis of dementia: a qualitative study in general practice. Br J Gen Pract 2012;62:e546-e553.
25. Bradford A, Kunik ME, Schulz P, et al. Missed and delayed diagnosis of dementia in primary care: prevalence and contributing factors. Alzheimer Dis Assoc Disord 2009;23:306.
26. Johnson G, Figueroa JF, Zhou X, et al. Recent growth in Medicare Advantage enrollment associated with decreased fee-for-service spending in certain US counties. Health Aff 2016;35:1707-1715.
27. Krumholz HM, Normand S-LT, Wang Y. Geographical health priority areas for older Americans. Health Aff 2018;37:104-110.