Journal of General Internal Medicine

, Volume 33, Issue 7, pp 1131–1138 | Cite as

Underdiagnosis of Dementia: an Observational Study of Patterns in Diagnosis and Awareness in US Older Adults

  • Halima Amjad
  • David L. Roth
  • Orla C. Sheehan
  • Constantine G. Lyketsos
  • Jennifer L. Wolff
  • Quincy M. Samus
Original Research



Many older adults living with dementia have not been formally diagnosed. Even when clinicians document the diagnosis, patients and families may be unaware of the diagnosis. Knowledge of how individual characteristics affect detection and awareness of dementia is limited.


To identify characteristics associated with dementia diagnosis and awareness of diagnosis.


Cross-sectional observational study.


Five hundred eighty-five adults aged ≥ 65 in the National Health and Aging Trends Study who met assessment-based study criteria for probable dementia in 2011 and had 3 years of continuous, fee-for-service Medicare claims prior to 2011.

Main Measures

Using multivariable logistic regression, we compared participants with undiagnosed versus diagnosed dementia (based on Medicare claims) on demographic, social/behavioral, functional, medical, and healthcare utilization characteristics. Among those diagnosed, we compared characteristics of participants unaware versus aware of the diagnosis (based on self or proxy report).

Key Results

Among older adults with probable dementia, 58.7% were either undiagnosed (39.5%) or unaware of the diagnosis (19.2%). In adjusted analyses, individuals who were Hispanic (OR 2.48, 95% CI 1.19, 5.14), had less than high school education (OR 0.54 for at least high school education, 95% CI 0.32, 0.91), attended medical visits alone (OR 1.98, 95% CI 1.11, 3.51), or had fewer functional impairments (OR 0.79 for each impairment, 95% CI 0.69, 0.90) were more likely to be undiagnosed. Similarly, among those diagnosed, having less education (OR 0.42), attending medical visits alone (OR 1.97), and fewer functional impairments (OR 0.72) were associated with unawareness of diagnosis (all ps < 0.05).


The majority of older adults with dementia are either undiagnosed or unaware of the diagnosis, suggesting shortcomings in detection and communication of dementia. Individuals who may benefit from targeted screening include racial/ethnic minorities and persons who have lower educational attainment, any functional impairment, or attend medical visits alone.


Geriatrics Dementia Alzheimer’s Diagnosis Vulnerable populations 



Prior presentations

This paper was presented at the International Association of Gerontology and Geriatrics (IAGG) World Congress in San Francisco, California on July 25, 2017.


The National Health and Aging Trends Study (NHATS) is funded by the National Institute on Aging (U01AG032947). Dr. Amjad received funding from the National Center for Advancing Translational Sciences/Johns Hopkins Institute for Clinical and Translational Research (KL2TR001077).

Compliance with Ethical Standards

Conflict of Interest

Dr. Lyketsos has served as a paid consultant for Astra-Zeneca, Glaxo-Smith Kline, Eisai, Novartis, Forest, Supernus, Adlyfe, Takeda, Wyeth, Lundbeck, Merz, Lilly, Pfizer, Genentech, Elan, NFL Players Association, NFL Benefits Office, Avanir, Zinfandel, BMS, Abvie, Janssen, Orion, Otsuka, and Astellas. He has also received honoraria or travel support from Pfizer, Forest, Glaxo-Smith Kline, and Health Monitor. Drs. Amjad, Roth, Sheehan, Wolff, and Samus declare that they do not have a conflict of interest.


  1. 1.
    Alzheimer's Association. 2017 Alzheimer's disease facts and figures. Alzheimer's & Dementia. 2017;13(4):325–73.CrossRefGoogle Scholar
  2. 2.
    Lang L, Clifford A, Wei L, et al. Prevalence and determinants of undetected dementia in the community: A systematic literature review and a meta-analysis. BMJ Open. 2017;7(2):e011146. doi: Scholar
  3. 3.
    Savva GM, Arthur A. Who has undiagnosed dementia? A cross-sectional analysis of participants of the Aging, Demographics and Memory Study. Age Ageing. 2015;44(4):642–7.CrossRefPubMedGoogle Scholar
  4. 4.
    Connolly A, Gaehl E, Martin H, Morris J, Purandare N. Underdiagnosis of dementia in primary care: Variations in the observed prevalence and comparisons to the expected prevalence. Aging Ment Health. 2011;15(8):978–84.CrossRefPubMedGoogle Scholar
  5. 5.
    Chodosh J, Petitti DB, Elliott M, et al. Physician recognition of cognitive impairment: Evaluating the need for improvement. J Am Geriatr Soc. 2004;52(7):1051–9.CrossRefPubMedGoogle Scholar
  6. 6.
    Amjad H, Roth DL, Samus QM, Yasar S, Wolff JL. Potentially unsafe activities and living conditions of older adults with dementia. J Am Geriatr Soc. 2016;64(6):1223–32.CrossRefPubMedPubMedCentralGoogle Scholar
  7. 7.
    Borson S, Frank L, Bayley PJ, et al. Improving dementia care: The role of screening and detection of cognitive impairment. Alzheimer's & Dementia. 2013;9(2):151–9.CrossRefGoogle Scholar
  8. 8.
    Moyer VA, U.S. Preventive Services Task Force. Screening for cognitive impairment in older adults: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2014;160(11):791–7.CrossRefPubMedGoogle Scholar
  9. 9.
    Fowler NR, Harrawood A, Frame A, et al. The Indiana University cognitive health outcomes investigation of the comparative effectiveness of dementia screening (CHOICE) study: Study protocol for a randomized controlled trial. Trials. 2014;15(1):209.CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Wilkins CH, Wilkins KL, Meisel M, Depke M, Williams J, Edwards DF. Dementia undiagnosed in poor older adults with functional impairment. J Am Geriatr Soc. 2007;55(11):1771–6.CrossRefPubMedGoogle Scholar
  11. 11.
    Ferretti M, Seematter-Bagnoud L, Martin E, Büla CJ. New diagnoses of dementia among older patients admitted to postacute care. Journal of the American Medical Directors Association. 2010;11(5):371–6.CrossRefPubMedGoogle Scholar
  12. 12.
    Eichler T, Thyrian JR, Hertel J, et al. Rates of formal diagnosis in people screened positive for dementia in primary care: Results of the DelpHi-trial. J Alzheimers Dis. 2014;42(2):451–8.CrossRefPubMedGoogle Scholar
  13. 13.
    Sternberg SA, Wolfson C, Baumgarten M. Undetected dementia in community-dwelling older people: The Canadian Study of Health and Aging. J Am Geriatr Soc. 2000;48(11):1430–4.CrossRefPubMedGoogle Scholar
  14. 14.
    NHATS data collection procedures: Round 1. 2011; Available at: Accessed January 22, 2018.
  15. 15.
    Montaquila J, Freedman V, Edwards B, and Kasper J. National Health and Aging Trends Study round 1 sample design and selection. NHATS Technical Paper #1. 2012; Available at: Accessed January 22, 2018.
  16. 16.
    Kasper J, Freedman V, and Spillman B. Classification of persons by dementia status in the National Health and Aging Trends Study. NHATS Technical Paper #5. 2013; Available at: Accessed January 22, 2018.
  17. 17.
    Galvin JE, Roe CM, Powlishta KK, et al. The AD8: A brief informant interview to detect dementia. Neurology. 2005;65(4):559–64.CrossRefPubMedGoogle Scholar
  18. 18.
    Galvin JE, Roe CM, Xiong C, Morris JC. Validity and reliability of the AD8 informant interview in dementia. Neurology. 2006;67(11):1942–8.CrossRefPubMedGoogle Scholar
  19. 19.
    CCW. Chronic Conditions Data Warehouse Condition Categories. Available at: Accessed January 22, 2018.
  20. 20.
    Montaquila J, Freedman V, and Kasper J. National Health and Aging Trends Study round 1 income imputation. NHATS Technical Paper #3. 2012; Available at: Accessed January 22, 2018.
  21. 21.
    Freedman VA, Kasper JD, Cornman JC, et al. Validation of new measures of disability and functioning in the National Health and Aging Trends Study. J Gerontol A Biol Sci Med Sci. 2011;66(9):1013–21.CrossRefPubMedGoogle Scholar
  22. 22.
    Löwe B, Kroenke K, Gräfe K. Detecting and monitoring depression with a two-item questionnaire (PHQ-2). J Psychosom Res. 2005;58(2):163–71.CrossRefPubMedGoogle Scholar
  23. 23.
    Kroenke K, Spitzer RL, Williams JB, Monahan PO, Löwe B. Anxiety disorders in primary care: Prevalence, impairment, comorbidity, and Detection. Ann Intern Med. 2007;146(5):317–25.CrossRefPubMedGoogle Scholar
  24. 24.
    Charlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: Development and validation. J Chronic Dis. 1987;40(5):373–83.CrossRefPubMedGoogle Scholar
  25. 25.
    Montaquila J, Freedman V, Spillman B, and Kasper J. National Health and Aging Trends Study development of round 1 survey weights. NHATS Technical Paper #2. 2012; Available at: Accessed January 22, 2018.
  26. 26.
    Ismail Z, Smith EE, Geda Y, et al. Neuropsychiatric symptoms as early manifestations of emergent dementia: Provisional diagnostic criteria for mild behavioral impairment. Alzheimer's & Dementia. 2016;12(2):195–202.CrossRefGoogle Scholar
  27. 27.
    Valcour VG, Masaki KH, Curb JD, Blanchette PL. The detection of dementia in the primary care setting. Arch Intern Med. 2000;160(19):2964–8.CrossRefPubMedGoogle Scholar
  28. 28.
    Borson S, Scanlan JM, Watanabe J, Tu S, Lessig M. Improving identification of cognitive impairment in primary care. Int J Geriatr Psychiatry. 2006;21(4):349–55.CrossRefPubMedGoogle Scholar
  29. 29.
    Livney MG, Clark CM, Karlawish JH, et al. Ethnoracial differences in the clinical characteristics of Alzheimer's disease at initial presentation at an urban Alzheimer's disease center. The American Journal of Geriatric Psychiatry. 2011;19(5):430–9.CrossRefPubMedPubMedCentralGoogle Scholar
  30. 30.
    Mayeda ER, Glymour MM, Quesenberry CP, Whitmer RA. Inequalities in dementia incidence between six racial and ethnic groups over 14 years. Alzheimer's & Dementia. 2016;12(3):216–24.CrossRefGoogle Scholar
  31. 31.
    Tang MX, Cross P, Andrews H, et al. Incidence of AD in african-americans, caribbean hispanics, and caucasians in northern Manhattan. Neurology. 2001;56(1):49–56.CrossRefPubMedGoogle Scholar
  32. 32.
    Connell CM, Scott Roberts J, McLaughlin SJ. Public opinion about Alzheimer disease among blacks, hispanics, and whites: Results from a national survey. Alzheimer Dis Assoc Disord. 2007;21(3):232–40.CrossRefPubMedGoogle Scholar
  33. 33.
    Connell CM, Scott Roberts J, McLaughlin SJ, Akinleye D. Racial differences in knowledge and beliefs about Alzheimer disease. Alzheimer Dis Assoc Disord. 2009;23(2):110–6.CrossRefPubMedGoogle Scholar
  34. 34.
    Mahoney DF, Cloutterbuck J, Neary S, Zhan L. African american, chinese, and latino family caregivers' impressions of the onset and diagnosis of dementia: Cross-cultural similarities and differences. Gerontologist. 2005;45(6):783–92.CrossRefPubMedPubMedCentralGoogle Scholar
  35. 35.
    Wood RY, Giuliano KK, Bignell CU, Pritham WW. Assessing cognitive ability in research: Use of MMSE with minority populations and elderly adults with low education levels. J Gerontol Nurs. 2006;32(4):45–54.PubMedGoogle Scholar
  36. 36.
    Brodaty H, Pond D, Kemp NM, et al. The GPCOG: A new screening test for dementia designed for general practice. J Am Geriatr Soc. 2002;50(3):530–4.CrossRefPubMedGoogle Scholar

Copyright information

© Society of General Internal Medicine 2018

Authors and Affiliations

  • Halima Amjad
    • 1
    • 2
  • David L. Roth
    • 1
    • 2
  • Orla C. Sheehan
    • 1
    • 2
  • Constantine G. Lyketsos
    • 3
  • Jennifer L. Wolff
    • 2
    • 4
  • Quincy M. Samus
    • 2
    • 3
  1. 1.Division of Geriatric Medicine and Gerontology Johns Hopkins University School of MedicineBaltimoreUSA
  2. 2.Johns Hopkins University Center on Aging and HealthBaltimoreUSA
  3. 3.Department of Psychiatry and Behavioral SciencesJohns Hopkins University School of MedicineBaltimoreUSA
  4. 4.Department of Health Policy and ManagementJohns Hopkins University Bloomberg School of Public HealthBaltimoreUSA

Personalised recommendations