The effect of education on age-related changes in three cognitive domains: a cross-sectional study in primary care.

The present study aims to investigate the protective effect of formal education on age-related changes in different cognitive domains with the hypothesis that it may attenuate the rate of decline. Individuals aged 50 years or older attending primary care physicians without known brain disease (431 participants, mostly [60.3%] female with 66.3 [±9.1] years of age and 7.7 [±4.1] years of education, on average), were evaluated with a neuropsychological battery including 28 cognitive measures. Cognitive domains identified by factor analysis were subject to repeated multiple regression analyses to determine the variance explained by age and education controlling for gender, depressive symptoms, and vascular risk factors. The slope of the regression equation was compared between two educational groups with an average of 4 years and 11 years of education, respectively. Factors identified corresponded to processing ability (Factor 1), memory (Factor 2), and acquired knowledge (Factor 3). Although education improved performance in Factors 1 and 3, it did not change the slope of age-related decline in any factor. This study suggests that in culturally heterogeneous groups, small increments in education enhance cognition but do not modify the rate of decline of executive functioning with age. These results contradict some clinical findings and need to be confirmed in longitudinal studies.