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The association between educational level and dementia in rural Tanzania

Associação entre nível educacional e demência na zona rural da Tanzânia

ABSTRACT

The majority of people with dementia worldwide live in developing countries. Studies from the developed world have reported an association between lower educational attainment and dementia, but there are few data from the developing world where literacy and educational levels are frequently much lower. In this study we assessed the association between education and dementia prevalence in a rural Tanzanian setting.

Methods:

In phase I, 1198 individuals aged 70 and over were assessed using the Community Screening Instrument for Dementia (CSI-D). In phase Ii a stratified sample of those seen in phase I were fully assessed and a clinical diagnosis based on DSM-IV criteria was made where appropriate. Information regarding literacy, highest attained educational level and occupation were also collected.

Results:

The median subject cognitive score on the CSI-D was 25.7 (IQR 22.7 to 28.0) for females and 27.7 (IQR 25.7 to 29.4) for males. This difference was significant (U=117770.0, z= -9.880, p<0.001). In both males and females a lower CSI-D subject cognitive score was significantly associated with having had no formal education (U=34866.5, z= -6.688, p<0.001, for females; U=20757.0, z= -6.278, p<0.001, for males). After adjusting for the effect of age, having no formal education was significantly associated with greater odds of having 'probable dementia' by CSI-D, as was illiteracy. Amongst those interviewed in phase II, there was no significant difference in literacy or education between those with diagnosed DSM-IV dementia and those without.

Conclusion:

In this rural Tanzanian population, we found a significant association between low levels of education and dementia by CSI-D. This relationship was not significant in cases meeting DSM-IV criteria for dementia.

Key words:
dementia; education; schooling; Tanzania; Africa

RESUMO

A maioria das pessoas com demência no mundo vivem em países em desenvolvimento. Estudos realizados em países desenvolvidos têm relatado uma associação entre baixa escolaridade e demência, onde os níveis de alfabetização e educação são frequentemente muito mais baixos. Neste estudo avaliou-se a associação entre a educação e a prevalência de demência em um cenário rural da Tanzânia.

Métodos:

Na fase I, 1.198 indivíduos com 70 anos ou mais foram avaliados utilizando o Instrumento de Rastreamento Comunitário para Demência (CSI-D). Na Fase II uma amostra estratificada dos pacientes avaliados na fase I foram totalmente avaliados e um diagnóstico clínico baseado em critérios do DSM-IV foi feito quando necessário.

Resultados:

A mediana do escore cognitivo no CSI-D foi de 25,7 (IQR 22,7-28,0) para o sexo feminino e 27,7 (IQR 25,7-29,4) para o sexo masculino. Esta diferença foi significativa (U=117770,0, z= -9,880, p <0,001). Em ambos os sexos, masculino e feminino a pontuação cognitiva menor no CSI-D foi significativamente associada com ausência de educação formal (U=34866,5, z= -6,688, p <0,001, para as mulheres;U=20757,0, z= -6,278, p<0.001, para o sexo masculino). Após o ajuste para o efeito da idade, ausência de educação formal foi significativamente associada com maiores chances de ter provável demência pelo CSI-D, como foi para o analfabetismo. Entre os entrevistados na fase II, não houve diferença significativa na alfabetização ou de educação entre aqueles com ou sem diagnóstico de demência do DSM-IV .

Conclusão:

Nesta população da Tanzânia rural, encontramos uma significativa associação entre baixos níveis de educação e demência pelo CSI-D. Esta relação não foi significativa em casos que preencheram os critérios do DSM-IV para demência.

Palavras-chave
demência; educação; escolaridade; Tanzânia; África

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Publication Dates

  • Publication in this collection
    Apr-Jun 2014

History

  • Received
    25 Mar 2014
  • Accepted
    29 May 2014
Academia Brasileira de Neurologia, Departamento de Neurologia Cognitiva e Envelhecimento R. Vergueiro, 1353 sl.1404 - Ed. Top Towers Offices, Torre Norte, São Paulo, SP, Brazil, CEP 04101-000, Tel.: +55 11 5084-9463 | +55 11 5083-3876 - São Paulo - SP - Brazil
E-mail: revistadementia@abneuro.org.br | demneuropsy@uol.com.br