Dementia and Neurocognitive Disorders (대한치매학회지)

Korean Dementia Association (대한치매학회)
권호 표지

Illiteracy Effect on Cognitive Decline in a Rural Elderly Population: A 3-year Follow up Study

지역사회에 거주하는 노인에서 문맹자와 비문맹자의 인지기능의 변화 비교: 3년 추적 연구

  • Kwon, Oh Dae (Department of Neurology, School of Medicine, Catholic University of Daegu) ;
  • Kwak, Jae Hyuk (Department of Neurology, School of Medicine, Catholic University of Daegu)
  • 권오대 (대구가톨릭대학교 의과대학 신경과학교실) ;
  • 곽재혁 (대구가톨릭대학교 의과대학 신경과학교실)
  • Published : 2011.06.30
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Abstract

Background: This study aimed to know the effects of illiteracy versus literacy on the longitudinal change of cognitive function in later life. Methods: The baseline and follow-up surveys were conducted in 2007 and 2010, respectively. The participants analyzed in the present study were 191 subjects who were 65 to 86 years old at baseline, living in a rural Korean community. Education level were categorized into three groups, illiterate (n=64) who cannot read and write even their own name, 1 to 5 yr of education (n=54), above 6 yr of education (n=73). Cognitive function was assessed using Korean version of Mini-Mental State Examination (K-MMSE), Clinical Dementia Rating (CDR) including CDR sum of boxes (CDR-SB), Korean version of Instrumental Activities of Daily Living (K-IADL) and Geriatric depression scale-short form (GDS-S). Demographic characteristics, past history of illness, family history, and life style were evaluated as covariates. Results: All the baseline neuropsychological tests were lower in illiterate group. Proportion of women was highest in illiterate group (92.2%), followed by low education (64.8%) and high education (28.8%). CDR-SB scores (F=3.788, p=0.024) and K-IADL (F=3.432, p=0.034), when adjusted for age and gender, showed that cognitive decline of illiterate group was severe than the literate two groups. On the other hand, K-MMSE scores (F=0.039, p=0.962), CDR-Global scores (F=1.950, p=0.145), and GDS-S scores (F=0.869, p=0.421) did not show significant differences among the three groups. Regression analysis showed that educational level (p=0.078) and family history of stroke (p=0.065) has marginal significance on the change in cognitive function. Conclusions: Illiterate subjects showed faster cognitive decline than literate subjects as well as lower baseline neuropsychological test scores, which support cognitive reserve theory.

Keywords

References

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