Objective: To determine the association of education and occupational attainment with dementia in late life and to clarify the nature of this frequently reported relationship.
Design: Cross-sectional study of the elderly members of a religious congregation.
Materials and Methods: The sample consisted of all members of the Poor School Sisters of Notre Dame in Bavaria aged 65 years or above (n=550). Participants were examined according to a standardized research protocol which included the CERAD-NP cognitive battery, CDR and GDS severity ratings, informant interviews using the IQ-CODE and the Bayer-ADL scale, a neurologic assessment, and blood sampling. Personal records were made available by the congregation which included information on education and occupational attainment. Multiple logistic regression analysis was used to determine the effects of levels of education and occupation on dementia, adjusting for age and apoE genotype. The highest level of education and occupation was used as a reference.
Results: Of 517 eligible sisters, 442 were examined in person (85.5%) and 75 refused to participate. The mean age of the participants was 78.4 years (SD=9.3; range 65 to 100 years). 104 of the 442 sisters were demented (23.5%). Severity of dementia was mild in 36%, moderate in 26%, and severe in 38%. Age-specific prevalence rates increased from 1.7% (65-69 years) to 59.6% (90+ years). Multiple logistic regression showed that after adjustment for age and apoE genotype, the risk of dementia was significantly increased for sisters with low education and poor occupational attainment. For elementary education (39% of the sample), an adjusted odds ratio (OR) of 4.4 (95%-CI 2.0-9.9) was found. Among sisters without vocational training (21% of the sample) the risk was even higher (OR = 8.4; 95%-CI 3.6-19.8). Intermediate educational and occupational levels did not differ significantly from the reference group. This pattern of association argues for a threshold effect rather than for a dose-response relationship.
Conclusion: In this large group of Catholic sisters, education and occupational attainment were strongly associated with prevalent dementia. The effect of these variables on the occurrence of dementia by far exceeded the effect of the apoE polymorphism. Since the sisters shared a similar environment throughout their adult life, it is unlikely that differences in lifestyle or in other environmental exposures are the sole explanation of the relationship between risk of dementia and educational background.
Back to S007 Quality of Life in Dementia: Is It Measurable and Is It Possible?
Back to The Eleventh International Congress