Education, Occupational Class, and Cognitive Decline in Preclinical Dementia

We investigated education and occupational influences as markers of cognitive reserve in relation to cognitive performance and decline on multiple fluid and crystallized abilities in preclinical dementia. From the total sample of 702 participants stemming from the OCTO-Twin Study (Sweden), aged 80+ at baseline in 1992-1993, only those who developed dementia during the study period (N = 127) were included in these analyses. Random effects models were used to examine the level of performance at the time of dementia diagnosis and the rates of decline prior to diagnosis. The results demonstrated that both fluid and crystallized abilities decline in preclinical stages, and that education and occupational class have independent moderating roles on the cognitive performance at the time of diagnosis, but not on the rates of decline.