O1-05-07

High educational acheivment has been shown to be protective against Alzheimer's Disease (AD). The cognitive reserve hypothesis suggests that this is because it is associated with greater cognitive reserve and thus higher cognitive performance for a given level of disease burden. It thus predicts that greater education and or occupational acheivement is associated with more rapid rates of decline proximal to the time of diagnosis due to increased disease burden. To test the cognitive reserve hypothesis by examining the effect of education and lifetime occupational achievement on memory decline during the preclinical course of dementia. We estimated rates of memory decline on the free recall score of the Buschke and Grober Free and Cued Selective Reminding Test with Immediate Recall (FCSRT–IR) as a function of education (measured in years) and occupational achievement (9 point scale) in 94 participants in the Einstein Aging Study age 70–97 who had detailed cognitive assessments at entry and at annual follow–up visits, and were diagnosed with incident dementia (70% AD or mixed). Linear mixed models were used to estimate the rate of cognitive decline as a function of time to diagnosis, and education or occupational achievement. Participants scored a mean of 23.5 on the FCSRT–IR (sd 8.2) at baseline and reported a mean of 12.6 years of formal education, with mean occupational achievement of 5.6. Occupational achievement and education were highly correlated (Spearman 0.67). The median follow up time before dementia diagnosis was 1.8 years (max 11.3 years). Participants reporting occupational achievement 4 or less declined 1.44 points per year (95% CI 0.68–2.20) on the FCSRT compared to 2.34 points per year (95% CI 1.91–2.78) for persons reporting occupational achievement 5 or higher. The difference was statistically significant (p=.045). Participants reporting 12 or fewer years of formal education declined 1.72 points per year (1.24, 2.19) and participants reporting more than 12 years declined 2.61 (1.94, 3.29) points per year, a statistically significant difference (p=.035). Thus as predicted by the cognitive reserve hypothesis, greater occupational and educational achievement are associated with more rapid cognitive decline in the years prior to dementia diagnosis.