Age and educational level effects on the performance of normal elderly on category verbal fluency tasks

Efeitos da idade e escolaridade no desempenho de idosos normais em tarefas de fluência verbal

Abstract

Cognitive decline, particularly executive dysfunction, is observed in normal aging. In Brazil, the elderly population presents broad educational diversity. Category verbal fluency tests are frequently used to detect cognitive impairment, assessing executive function, language and semantic memory.

Objective:

To investigate the effects of age and education on category animal fluency task (CAF) in healthy elderly.

Methods:

We evaluated 319 healthy elderly from outpatient care units of two university reference centers of Rio de Janeiro and São Paulo. The sample was divided into two age, and five schooling subgroups. To be included participants had to demonstrate preservation of global cognitive functioning, independence for activities of daily living and not fulfill diagnostic criteria for dementia. All participants were submitted to neurological and neuropsychological evaluations.

Results:

There was a correlation between age and CAF performance (r= -0.26, p<0.01), which was not confirmed when years of education were included as a covariant in univariate ANCOVA. Significant differences were found in CAF performance among the different educational level groups on correlation analysis (r=0.42, p<0.01) and ANCOVA analysis (F=18.8, p<0.05). Illiteracy was associated with worst CAF performance, while university level was associated with best performance.

Conclusion:

The best CAF performance was found in the first years of schooling (literacy learning process) compared to illiteracy, and when finishing high school and starting university courses compared to all other educational levels. These stages are associated with significant gains in semantic memory and executive function which are critical for verbal fluency performance.

Key words:
aged; animal fluency; educational status.

Resumo

Declínio cognitivo, particularmente o funcionamento executivo é observado com aumento da idade em idosos saudáveis. No Brasil, a população idosa apresenta grande diversidade educacional. A fluência verbal semântica é um teste freqüentemente usado para detectar comprometimento cognitivo, avaliando funções executivas, linguagem e memória semântica. Objetivo: Investigar o efeito da idade e níveis educacionais na fluência semântica de animais em idosos saudáveis.

Métodos:

A amostra foi composta de 319 idosos saudáveis, divididos em duas categorias de idade e cinco níveis de escolaridade, provenientes de centros universitários de referência do Rio de Janeiro e São Paulo. Todos apresentaram: preservação do funcionamento cognitivo global, independência nas atividades da vida diária e não preencher critérios para demência. Todos os participantes foram submetidos à avaliação neurológica e neuropsicológica.

Resultados:

Houve correlação entre idade e desempenho na tarefa de fluência verbal animais (r= -0,26, p<0,01), não confirmada quando os anos de escolaridade foram incluídos como covariante no ANCOVA univariado. Diferenças significativas foram encontradas entre escolaridade e desempenho da fluência verbal animais tanto na análise de correlação (r=0,42, p<0,01) quanto na análise ANCOVA (F=18,8, p<0,05). Analfabetismo foi associado ao pior desempenho, enquanto o nível universitário foi associado com o melhor desempenho na fluência verbal de animais.

Conclusão:

A maior diferença de desempenho na fluência verbal animais foi encontrada nos primeiros anos de escolarização (processo de aprendizagem da alfabetização) quando comparado com os analfabetos e quando se finaliza o ensino médio e ingressa na universidade comparado aos demais níveis de escolaridade. Estes estágios estão associados com o aperfeiçoamento da memória semântica e de funções executivas, que são essenciais para o desempenho no teste de fluência verbal.

Palavras-chave:
idosos saudáveis; fluência verbal semântica; nível educacional.

Texto completo disponível apenas em PDF.

Full text available only in PDF format.

References

• ¹
  Camarano AA. (org.). Os novos idosos brasileiros. Muito além dos 60 anos. Rio de Janeiro: IPEA 2004.
• ²
  Argimon IIL, Stein LM. Habilidades cognitivas em indivíduos muito idosos: um estudo longitudinal. Cad Saúde Pública 2005;21:64-72.
• ³
  Banhato EFC, Nascimento E . Função executiva em idosos: um estudo utilizando subtestes da Escala WAIS-III. PsicoUSF 2007;12:65-73.
• ⁴
  Scuteri A, Palmieri L, Lo Noce C, Giampaoli S. Age-related changes in cognitive domains. A population-based study. Aging Clin Exp Res. 2005;17:367-73.
• ⁵
  Lin H, Chan RC, Zheng L, Yang T, Wang Y. Executive functioning in healthy elderly Chinese people. Arch Clin Neuropsychol 2007;22:501-511.
• ⁶
  Damoiseaux JS, Beckmann CF, Arigita EJ, Barkhof F, Scheltens P, Stam CJ, Smith SM, Rombouts SA. Reduced resting-state brain activity in the "default network" in normal aging. Cereb Cortex 2008; 18:1856-1864.
• ⁷
  Woodruff-Pak DS. The Neuropsychology of aging. Malden: Blackwell Publishers;1997.
• ⁸
  Correia MVG, Teixeira CCG, Araújo JF, et al. Perfil cognitivo em idosas de dois serviços públicos em São Luís - MA. Rev Psiquiatr Clin 2008;35:131-137
• ⁹
  Lezak M. Neuropsychological Assessment. New York: Oxford University Press;1995.
• ¹⁰
  Brucki SMD, Rocha MSG. Category fluency test: effects of age, gender and education on total scores, clustering and switching in Brazilian Portuguese-speaking subjects. Braz J Med Res 2004;37:1771-1777
• ¹¹
  Caramelli P, Carthery-Goulart MT, Porto CS, Charchat Fichman H, Nitrini R. Category Fluency as a Screening Test for Alzheimer Disease in Illiterate and Literate Patients -Brief Report. Alzheimer Dis Assoc Disorder 2007;21:65-67.
• ¹²
  Gomez RG, White DA. Using verbal fluency to detect very mild dementia of the Alzheimer type. Arch Clin Neuropsychol 2006;21:771-775.
• ¹³
  Mathuranath PS, George A, Cherian PJ, Alexander A, Sarma1 SG, Sarma PS. Effects of Age, Education and Gender on Verbal Fluency. J Clin Exp Neuropsychol 2003;25:1057-1064.
• ¹⁴
  Murphy KJ, Rich JB, Troyer AK. Verbal Fluency patterns in amnestic mild cognitive impairment are characteristic of Alzheimer's type dementia. Brief communication. J Int Neuropsychol Soc 2006;12:570-574.
• ¹⁵
  Nóbrega E, Nieto A, Barroso, J, Montón, F. Differential impairment in semantic, phonemic, and action fluency performance in Frieidreich's ataxia: Possible evidence of prefrontal dysfunction. J Int Neuropsychol Soc 2007;13:944-952.
• ¹⁶
  Balthazar MLF, Cendes F, Damasceno BP. Category verbal fluency performance may be impaired in amnestic mild cognitive impairment. Dement Neuropsychol 2007;2:161-165.
• ¹⁷
  Kempler D, Teng EL, Dick M, Taussig IM, Davis DS. The effects of age, education, and ethnicity on verbal fluency. J Int Neuropsychol Soc 1998;4:531-538.
• ¹⁸
  Radanovic M, Carthery-Goulart MT, Charchat Fichman H, Herrera Jr E, Lima EEP, Smid J, Porto CS, Nitrini R. Analysis of brief language tests in the detection of cognitive decline and dementia. Dement Neuropsychol 2007;1:37-45
• ¹⁹
  Rascovsky K, Salmon DP, Hansen LA, Thal LJ, Galasko D. Disparate letter and semantic category fluency deficits in autopsy-confirmed frontotemporal dementia and Alzheimer's disease. Neuropsychology 2007;21:20-30 .
• ²⁰
  Braaten A, Parsons T, McCue R, Sellers A, Burns W. Neurocognitive differential diagnosis of dementing diseases: Alzheimer's dementia, vascular dementia, frontotemporal dementia, and major depressive disorder. Int J Neurosc 2006;116:1271-1293.
• ²¹
  Spreen O, Strauss E. Compendium of Neuropsychological Tests, Administration, Norms and Commentary. Oxford: Oxford University Press;1998
• ²²
  Forbes-McKay KE, Ellis AW, Shanks MF, Venneri A. The age of acquisition of words produced in a semantic fluency task can reliably differentiate normal from pathological age related cognitive decline. Neuropsychologia 2005;11:1625-1632.
• ²³
  Piovezan MR, Teive HAG, Piovesan EJ, Mader MJ, Werneck LC. Cognitive function assessment in idiopathic Parkinson's Disease. Arq Neuropsiquiatr 2007;65:942-946.
• ²⁴
  Schwartz S, Baldo J, Graves RE, Brugger P. Pervasive influence of semantics in letter and category fluency: A multidimensional approach. Brain Lang 2003;87:400-411
• ²⁵
  Leibovici D, Ritchie K, Ledesert B, Touchon J. Does Education Level Determine the Course of Cognitive Decline? Age Ageing 1996;25:392-397.
• ²⁶
  Barnes DE, Targer IB, SatariAno WA, Yaffe K. The Relationship Between Literacy and Cognition in Well-Educated Elders. Journal of Gerontology: Med Sci 2004;59A:390-395.
• ²⁷
  Nitrini R, Caramelli P, Herrera Junior E, et al. Performance of illiterate and literate nondemented elderly subjects in two tests of long-term memory. J Int Neuropsychol Soc 2004;10:634-638.
• ²⁸
  Barea KS, Mansur LL. Knowledge of semantic categories in normal aged. Influence of education. Dement Neuropsychol 2007;2:166-172.
• ²⁹
  Folstein M, Folstein S, Mchugh P. Mini-mental state: a practical method for grading the cognitive state off patients for the clinician. J Psychiatr Res 1975;12:189-198.
• ³⁰
  Brucki SM, Nitrini R, Caramelli P, Bertolucci PH, Okamoto IH. Sugestões para o uso do mini-exame do estado mental no Brasil. Arq Neuropsiquiatr 2003;61:777-781.
• ³¹
  Pfeffer RI, Kurosaki TT, Harmash JR, Chance JM, Filos S. Measurement of functional activities in older adults in the community. J Gerontol 1982;37:323-329.
• ³²
  Lawton MP, Brody EM. Assessment of older people: Self-maintaining and instrumental activities of daily living. Gerontologist 1969;9:179-186.
• ³³
  American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4 ed. Washigton, DC: American Psychiatric Association;1994.
• ³⁴
  Yassuda MS, Diniz BS, Flaks MK, et al. Neuropsychological profile of Brazilian older adults with heterogeneous educational backgrounds. Arch Clin Neuropsychol. 2008;26.
• ³⁵
  Ratcliff G, Ganguli M, Chandra V, et al. Effects of literacy and education on measures of word fluency. Brain Lang 1998;61: 115-122.
• ³⁶
  Stern Y. What is cognitive reserve? Theory and research application of the reserve concept. J Int Neuropsychol Soc 2002;8: 448-460.

Publication Dates

• Publication in this collection
  Jan-Mar 2009

History

• Received
  12 Dec 2008
• Accepted
  05 Feb 2009