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

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%: 1.164.81 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.