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Identification of dementia in epidemiological research: a study on the usefulness of various data sources

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Abstract

Background and aims: Prevalence and incidence ratios of dementia in epidemiological studies vary according to the data source used. Medical records, cognitive tests, and registry information are sources frequently used to differentiate dementia from normal aging. The aim of the present study was to compare the identification of dementia from these different sources with that from consensus diagnosis. Methods: 498 elderly people (age range 70–81 at baseline) enrolled in a Swedish population-based longitudinal twin study (Gender) were evaluated on physical and mental health and interviewed for their socio-demographic background three times during an eight-year period. Reviews of medical records and the Swedish Discharge Registry (DR) were conducted. The 10th percentile was used to differentiate between dementia and non-dementia in all cognitive tests. Scores of 24 or below on the Mini-Mental State Examination (MMSE) (range 1–30) indicated dementia. A consensus conference diagnosed dementia on the basis of total information. The consensus diagnosis was used as the gold standard. Results: MMSE scores (sensitivity 64%, specificity 96%, kappa 0.65) and the review of medical records (sensitivity 57%, specificity 99%, kappa 0.65) were good sources for dementia identification. The precision of medical records increased when recordings of cognitive impairment were included (sensitivity 83%, specificity 98%, kappa 0.84). The discharge registry had low sensitivity (26%) and kappa coefficient (0.31). Conclusions: The present study shows that both review of medical records and MMSE scores are good although not perfect identifiers of dementia. The discharge registry is an uncertain source of dementia identification.

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References

  1. Ganguli M, Dodge H, Chen P, Belle S, DeKosky S. Ten-year incidence of dementia in a rural elderly US community population — the MoVIES project. Neurology 2000; 54: 1109–16.

    Article  PubMed  CAS  Google Scholar 

  2. Hendrie H, Ogunniyi A, Hall K, et al. Incidence of dementia and Alzheimer disease in 2 communities — Yoruba residing in Ibadan, Nigeria, and African Americans residing in Indianapolis, Indiana. JAMA 2001; 285: 739–47.

    Article  PubMed  CAS  Google Scholar 

  3. Folstein M, Folstein S, McHugh P. “Mini-Mental State” — a practical method for grading the cognitive state of patients for the clinician. J Psychiatr Res 1975; 12: 189–98.

    Article  PubMed  CAS  Google Scholar 

  4. Löppönen M, Räihä I, Isoaho R, Vahlberg T, Kivelä SL. Diagnosing cognitive impairment and dementia in primary health care — a more active approach is needed. Age & Ageing 2003; 32: 606–12.

    Article  Google Scholar 

  5. Chodosh J, Pettiti D, Elliott M, et al. Physician recognition of cognitive impairment — evaluating the need for improvement. J Am Geriatr Soc 2004; 52: 1051–9.

    Article  PubMed  Google Scholar 

  6. Olafsdottir M, Skoog I, Marcusson J. Detection of dementia in primary care — the Linköping study. Dement Geriatr Cogn Disord 2000; 11: 223–9.

    Article  PubMed  CAS  Google Scholar 

  7. Callahan C, Hendrie H, Tierney W. Documentation and evaluation of cognitive impairment in elderly primary care patients. Ann Intern Med 1995; 122: 422–9.

    Article  PubMed  CAS  Google Scholar 

  8. Tuokko H, Kristjansson E, Miller J. Neuropsychological detection of dementia — an overview of the neuropsychological component of the Canadian Study of health and aging. J Clin Exp Neu- ropsychol 1995; 17: 352–73.

    Article  CAS  Google Scholar 

  9. Ganguli M, Belle S, Ratcliff G, et al. Sensitivity and specificity for dementia of population-based criteria for cognitive impairment — the MoVIES project. J Gerontol Med Sci 1993; 48: M152–61.

    Article  CAS  Google Scholar 

  10. Jin Y-P, Gatz M, Johansson B, Pedersen N. Sensitivity and specificity of dementia coding in two Swedish disease registries. Neurology 2004; 63: 739–41.

    Article  PubMed  Google Scholar 

  11. Rosén MA. A finger on the pulse — monitoring public health and social conditions in Sweden 1992–2002. Available at http//www.socialstyrelsen.se/Publicerat/2003/1611/2003-118-16.htm/Publicerat/2003/1611/2003-118-16.htm (061008).

  12. Cederlöf R, Lorich U. Untitled. In Nance WE, Allen G, Parisi P, Eds. Twin Research: Part C. Biology and Epidemiology. New York: Alan R Liss, 1978: 189–95.

    Google Scholar 

  13. Gold C, Malmberg B, McClearn G, Pedersen N, Berg S. Gender and health — a study of older unlike-sex twins. J Gerontol Soc Sci 2002; 57B: 168–76.

    Article  Google Scholar 

  14. Dureman I, Kebbob L, Osterberg E. Manual till DS-batteriet (Manual of the DS-battery). Stockholm: Psykologi Förlaget, 1971.

    Google Scholar 

  15. Ekström R, French J, Harman H. Manual kit of factor referenced cognitive tests. Princeton: Educational Testing Service, 1976.

    Google Scholar 

  16. Thurstone L. Primary mental abilities. Chicago: University of Chicago Press, 1938.

    Google Scholar 

  17. Morris J, Heyman A, Mohs R. The consortium to establish a registry for Alzheimer’s disease (CERAD): 1.Clinical and neuropsychological assessment of Alzheimer’s disease. Neurology 1989; 39: 1159–965.

    Article  PubMed  CAS  Google Scholar 

  18. Berger E. A system of rating the severity of senility. J Am Geriatric Soc 1980; 28: 234–6.

    CAS  Google Scholar 

  19. American Psychiatric Association. Diagnostic and statistical manual of mental disorders, 4th ed. Washington, DC: American Psychiatric Association, 2000.

    Google Scholar 

  20. World Health Organization. International statistical classification of disease and related problems, 10th ed. Geneva: World Health Organization, 1994.

    Google Scholar 

  21. Kanaya A, Barrett-Connor E, Gildengorin G, Yaffe K. Change in cognitive function by glucose tolerance status in older adults — a 4-year prospective study of the Rancho Bernardo study cohort. Arch Intern Med 2004; 164: 1327–33.

    Article  PubMed  Google Scholar 

  22. Altman D. Practical statistics for medical research. Great Britain: Chapman & Hall, 1991.

    Google Scholar 

  23. Maeck L, Haak S, Knoblauch A, Stoppe G. Early diagnosis of dementia in primary care — a representative eight-year follow-up study in Lower Saxony, Germany. Int J Geriatr Psychiatry 2007; 22: 23–31.

    Article  PubMed  Google Scholar 

  24. Tombaugh T, McIntyre N. The Mini-Mental State Examination — a comprehensive review. J Am Geriatric Soc 1992; 40: 922–35.

    CAS  Google Scholar 

  25. Räihä I, Isoaho R, Ojanlatva A, Viramo P, Sulkava R, Kivelä SL. Poor performance in the Mini-Mental State Examination due to causes other than dementia. Scand J Prim Health Care 2001; 19: 34–8.

    Article  PubMed  Google Scholar 

  26. Oosterman J, Scherder E. Distinguishing between vascular dementia and Alzheimer’s disease by means of the WAIS — a meta-analysis. J Clin Exp Neuropsychol 2006; 28: 1158–75.

    Article  PubMed  Google Scholar 

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Dahl, A., Berg, S. & Nilsson, S.E. Identification of dementia in epidemiological research: a study on the usefulness of various data sources. Aging Clin Exp Res 19, 381–389 (2007). https://doi.org/10.1007/BF03324718

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