Advertisement

Aging Clinical and Experimental Research

, Volume 14, Issue 2, pp 132–142 | Cite as

Cognitive decline is related to education and occupation in a Spanish elderly cohort

  • Beatriz E. Alvarado
  • Maria-Victoria Zunzunegui
  • Teodoro Del Ser
  • François Béland
Original Articles

Abstract

Background and aims: The type of education and occupation can sensibly influence cognitive decline. The aim of this study was to examine their impact on cognitive function in a longitudinal study of community-dwelling Spanish people over 65 with low levels of formal education and predominantly unskilled occupations. Methods: Cognitive function was assessed in 1993 and 1997 using a simple scale including items of memory and orientation that has been previously validated for populations with low levels of formal education. Cognitive score in 1997 and cognitive decline over 4 years (1993–1997) were used as outcomes. Education and occupation were analyzed as determinants of cognitive function using multiple linear regression, and of cognitive decline using logistic and multinomial regressions. Results: Of the 557 subjects who completed the follow-up in 1997, 11% had experienced severe decline and 20.6% mild decline. Overall and mild cognitive decline were predicted by low education and being a farm worker (OR: 2.36, CI 95%: 1.16–4.81 and OR: 2.37, CI 95%: 1.05–5.37) after controlling for age. Conclusions: Cognitive decline in the elderly is partially explained by early life events, such as education, and living in a deprived environment over a long period of time. We cannot ascertain whether these effects are direct or mediated by other associated conditions but sample attrition does not account for our results.

Keywords

Aging cognitive decline education life course longitudinal study occupation 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Evans DA, Beckett LA, Albert MS, et al. Level of education and change in cognitive function in a community population of older persons. Ann Epidemiol 1993; 3: 71–7.PubMedCrossRefGoogle Scholar
  2. 2.
    White LR, Katzman R, Losonczy K, et al. Association of education with incidence of cognitive impairment in three established populations for epidemiological studies of the elderly. J Clin Epidemiol 1994; 47: 363–74.PubMedCrossRefGoogle Scholar
  3. 3.
    Farmer ME, Kittner SJ, Rae DS, Bartko JJ, Regier DA. Education and change in cognitive function: the epidemiological catchments area study. Ann Epidemiol 1995; 5: 76–8.CrossRefGoogle Scholar
  4. 4.
    Jacqmin-Gadda H, Fabrigoule C, Commenges D, Dartigues JF. A 5 year longitudinal study of the Mini Mental State Examination in normal aging. Am J Epidemiol 1997; 145: 498–506.PubMedCrossRefGoogle Scholar
  5. 5.
    Bickel H, Cooper B. Incidence and relative risk of dementia in an urban elderly population: findings of a prospective field study. Psychol Med 1994; 24: 179–92.PubMedCrossRefGoogle Scholar
  6. 6.
    Stern Y, Gurland B, Tatemichi TK, Tang MX, Wilder D, Mayeux R. Influence of education and occupation on the incidence of Alzheimer’s disease. JAMA 1994; 271: 1004–10.PubMedCrossRefGoogle Scholar
  7. 7.
    Evans DA, Herbert LE, Beckett LA, et al. Education and other measures of socio-economic status and risk of incident Alzheimer’s disease in a defined population of older persons. Arch Neurol 1997; 54: 1399–405.PubMedCrossRefGoogle Scholar
  8. 8.
    Ritchie K, Touchon J, Ledesert B, Leibovici D, Dupuy-Gorge M. Establishing the limits and characteristics of normal age-related cognitive decline. Rev Epidem et Santé Publ 1997; 45: 373–81.Google Scholar
  9. 9.
    Schmand B, Smit J, Lindeboom J, et al. Low education is a genuine risk factor for accelerated memory decline and dementia. J Clin Epidemiol 1997; 50: 1025–33.PubMedCrossRefGoogle Scholar
  10. 10.
    Stern Y, Albert S, Tang MX, Tsai WY. Rate of memory decline in AD is related to education and occupation. Cognitive reserve? Neurology 1999; 53: 1942–7.Google Scholar
  11. 11.
    O’Connor DW, Pollitt PA, Treasure FP. The influence of education and social class on the diagnosis of dementia in a community population. Psychol Med 1991; 21: 219–24.PubMedCrossRefGoogle Scholar
  12. 12.
    Beard CM, Kokmen E, Offord KP, Kurland LT. Lack of association between Alzheimer’s disease and education, occupation, marital status, or living arrangement. Neurology 1992; 42: 2063–8.PubMedCrossRefGoogle Scholar
  13. 13.
    Paykel ES, Brayne C, Huppert FA, et al. Incidence of dementia in a population older than 75 years in the United Kingdom. Arch Gen Psychiatry 1994; 51: 325–32.PubMedCrossRefGoogle Scholar
  14. 14.
    Cobb JL, Wolf PA, Au R, White R, D’Agostino RB. The effect of education on the incidence of dementia and Alzheimer’s disease in the Framingham study. Neurology 1995; 45: 1707–12.PubMedCrossRefGoogle Scholar
  15. 15.
    Jorm AF, Rodgers B, Henderson AS, et al. Occupation type as a predictor of cognitive decline and dementia in old age. Age Ageing 1998; 27: 477–83.PubMedCrossRefGoogle Scholar
  16. 16.
    Friedland RP. Epidemiology, education and the ecology of Alzheimer’s disease. Neurology 1993; 43: 246–9.PubMedCrossRefGoogle Scholar
  17. 17.
    Katzman R. Education and the prevalence of dementia and Alzheimer’s disease. Neurology 1993; 43: 13–20.PubMedCrossRefGoogle Scholar
  18. 18.
    Albert M. How does education affect cognitive function? Ann Epidemiol 1995; 5: 76–8.PubMedCrossRefGoogle Scholar
  19. 19.
    Fratiglioni L. Epidemiology of Alzheimer’s disease and current possibilities for prevention. Acta Neurol Scand 1996; 165: 33–40.CrossRefGoogle Scholar
  20. 20.
    Del Ser T, Hachinsky V, Merskey H, Muñoz DG. An autopsy-verified study of the effect of education on degenerative dementia. Brain 1999; 122: 2309–19.PubMedCrossRefGoogle Scholar
  21. 21.
    Dartigues JF, Gagnon M, Letteneur L, et al. Principal lifetime occupation and cognitive impairment in a French elderly cohort. PAQUID. Am J Epidemiol 1992; 135: 981–8.Google Scholar
  22. 22.
    Canadian Study of Health and Aging. Risk factors for Alzheimer’s disease in Canada. The Canadian Study of Health and Aging Working Group. Neurology 1994; 44: 2073–80.Google Scholar
  23. 23.
    Alexander GE, Furey ML, Grady CL, et al. Association of premorbid intellectual function with cerebral metabolism in Alzheimer’s disease: implications for the cognitive reserve hypothesis. Am J Psychiatry 1997; 154: 165–72.PubMedGoogle Scholar
  24. 24.
    Schofield PW, Mosesson RE, Stern Y, Mayeux R. The age at onset of Alzheimer’s disease and an intracranial area measurement. Arch Neurol 1995; 52: 95–8.PubMedCrossRefGoogle Scholar
  25. 25.
    Coffey CE, Saxton JA, Ratcliff G, et al: Relation of education to brain size in normal aging. Implications for the reserve hypothesis. Neurology 1999; 53: 189–95.PubMedCrossRefGoogle Scholar
  26. 26.
    Reynolds MD, Johnston JM, Dodge HH, DeKosky ST, Ganguli M. Small head size is related to low Mini-Mental State Examination scores in a community sample of nondemented older adults. Neurology 1999; 53: 228–9.PubMedCrossRefGoogle Scholar
  27. 27.
    Berkman LF. The association between educational attainment and mental status examinations: of etiological significance for senile dementias or not? J Chron Dis 1986; 39: 171–4.PubMedCrossRefGoogle Scholar
  28. 28.
    Gomemann I, Zunzunegui MV, Martinez C, Onís MC. Screening for Impaired Cognitive Function among the Elderly in Spain: Reducing the Number of Items in the SPMSQ. Psychiatry Res 1999; 89: 133–45.CrossRefGoogle Scholar
  29. 29.
    Zunzunegui MV, Beland F, Gutierrez-Cuadra P. Lost of followup in a longitudinal study of ageing in Spain. J Clin Epidemiol 2001; 54: 501–10.PubMedCrossRefGoogle Scholar
  30. 30.
    Pfeiffer E. A short portable mental status questionnaire for the assessment of organic brain deficit in elderly patients. J Am Geriatr Soc 1975; 23: 433–40.PubMedGoogle Scholar
  31. 31.
    Instituto Nacional de Estadística. Clasificación Nacional de Ocupaciones. Madrid: INE, 1979.Google Scholar
  32. 32.
    Zunzunegui MV, Gutierrez-Cuadra P, Béland F, del Ser T, Wolfson C. Development of simple cognitive function measures in a community dwelling population of elderly in Spain. Int J Geriatr Psychiatry 2000; 15: 130–40.PubMedCrossRefGoogle Scholar
  33. 33.
    Hosmer DW, Lemeshow S. Applied Logistic Regression. John Wiley and Sons, 1991.Google Scholar
  34. 34.
    Yu ESH, Liu WT, Levy P, et al. Cognitive impairment among elderly adults in Shanghai, China. J Gerontol 1989; 3: S97–106.CrossRefGoogle Scholar
  35. 35.
    Liu HC, Lin KN, Wang SJ, et al. Assessing cognitive abilities and dementia in a predominantly illiterate population of older individuals in Kinmen. Psychol Med 1994; 24: 763–70.PubMedCrossRefGoogle Scholar
  36. 36.
    Anzola E, Bangdiwala S, Barrientos del Llano G, De la Vega H, Dominguez O, Bern M. Towards community diagnosis of dementia. Testing cognitive impairment in older persons in Argentina, Chile and Cuba. Int J Geriatr Psychiatry 1996; 11: 429–38.Google Scholar
  37. 37.
    Zhang M, Katzman R, Salmon D, et al. The prevalence of dementia and Alzheimer’s disease in Shanghai, China. Impact of age, gender and education. Ann Neurol 1990; 27: 428–37.Google Scholar
  38. 38.
    De Ronchi D, Fratiglioni L, Rucci P, et al. The effect of education on dementia occurrence in an Italian population with middle to high socio-economic status. Neurology 1998; 50: 1231–8.PubMedCrossRefGoogle Scholar
  39. 39.
    Zhang M, Katzman R, Yu E, Liu W, Xiao SF, Yan H. A preliminary analysis of incidence of dementia in Shanghai, China. Psychiatry Clin Neurosci 1998; 52: S291–4.PubMedGoogle Scholar
  40. 40.
    Ott A, Breteler MMB, van Harskamp F, Stinjnon T, Hoffman A. Incidence and risk of dementia. The Rotterdam study. Am J Epidemiol 1998; 147: 574–80.CrossRefGoogle Scholar
  41. 41.
    Ganguli M, Dodge HH, Chen P, Belle S, Dekosky ST. Ten year incidence of dementia in a rural elderly US community population. The MoVIES project. Neurology 2000; 54: 1109–16.CrossRefGoogle Scholar
  42. 42.
    Scherr PA, Albert MS, Kunkensten HH, et al. Correlates of cognitive function in an elderly population. Am J Epidemiol 1988; 128: 1084–101.PubMedGoogle Scholar
  43. 43.
    Schmand B, Smit JH, Geerlings MI, Lindeboom J. The effects of intelligence and education on the development of dementia. A test of the brain reserve hypothesis. Psychol Med 1997; 27: 1337–44.Google Scholar
  44. 44.
    Brayne C, Gill C, Paykel ES, Huppert F, O’Connor DW. Cognitive decline in an elderly population. A two wave study of change. Psychol Med 1995; 25: 673–83.Google Scholar
  45. 45.
    Körten AE, Henderson AS, Cristensen H, et al. A prospective study of cognitive function in the elderly. Psychol Med 1997; 27: 919–30.PubMedCrossRefGoogle Scholar
  46. 46.
    Rocca W, Cha RH, Waring SC, Kokmen E. Incidence of dementia and Alzheimer’s disease. A reanalysis of data from Rochester, Minnesota, 1975–1984. Am J Epidemiol 1998; 148: 51–62.Google Scholar
  47. 47.
    Berr C, Dartigues JF, Alperovitch A. Cognitive performance and three year mortality in the PAQUID elderly study. Rev Epidemiol et Santé Publique 1994; 42: 277–84.Google Scholar
  48. 48.
    Bassuk SS, Wypij D, Berkman LF. Cognitive impairment and mortality in the community dwelling elderly. Am J Epidemiol 2000; 151: 676–88.PubMedCrossRefGoogle Scholar
  49. 49.
    Morris MC, Evans DA, Herbert LE, Bienias IL. Methodological issues in the study of cognitive decline. Am J Epidemiol 1999; 149: 789–93.PubMedCrossRefGoogle Scholar
  50. 50.
    Snijders TAB, Bosker RJ. Longitudinal data. In Snijders TAB, Bosker RJ, eds. Multilevel analysis. An introduction to basic and advanced multilevel modeling. Sage publications, 1999: 166–81.Google Scholar
  51. 51.
    Kuh D, Blane D, Bartley M. Social pathways between childhood and adult health. In Kuh D, Ben-Shlomo Y, eds. A life course approach to chronic disease epidemiology. Oxford: University Press, 1997: 169–98.Google Scholar
  52. 52.
    Berkman LF, Kawachi I. A historical framework for social epidemiology. In Berkman LF, Kawachi I, eds. Social Epidemiology. Oxford University Press, 2000: 3–12.Google Scholar

Copyright information

© Springer Internal Publishing Switzerland 2002

Authors and Affiliations

  • Beatriz E. Alvarado
    • 1
  • Maria-Victoria Zunzunegui
    • 1
  • Teodoro Del Ser
    • 2
  • François Béland
    • 3
  1. 1.Département de Médecine Sociale et Préventive, Faculté de MédecineUniversité de MontréalMontréalCanada
  2. 2.Sección de NeurologíaHospital Severo OchoaLeganesSpain
  3. 3.GRISUniversité de MontréalQuébecCanada

Personalised recommendations