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

Abstract

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. 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. 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. 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.