PROTECTIVE EFFECT OF LIFETIME EXPERIENCES ON FUNCTIONAL STATUS IN YOUNG-ONSET DEMENTIA

Patients with Frontotemporal degeneration (FTD), a common form of young-onset dementia, experience decline in cognitive, social and daily functioning as the disease progresses. Research shows that lifestyle factors may be an important modifiable risk factor for dementia, but this has not been well studied in FTD. In this study, we test the hypothesis that lifetime experiences, including education, occupation, and leisure activities, are associated with better functional status in individuals with FTD. We also evaluated the relationship between timing of experiences (early, mid-life, and late-life) and functional status. Thirty-five patients (mean age 61.6±8.7; 74% male; mean disease duration 3.4 ± 2.6; mean MMSE 24.0 ± 5.5) completed the Lifetime of Experiences Questionnaire (LEQ), a comprehensive assessment of lifelong cognitive lifestyle, and the Clinical Dementia Rating Scale (CDR), which was used to assess functional status. Linear regression tested the relationship between cognitive lifestyle and functional status, with age and disease duration included as covariates. Higher total LEQ score was associated with better functional status (lower score on CDR) (β = -0.047, p = 0.009). While Young Adulthood LEQ score was not significantly associated with total CDR (β = -0.047, p = 0.176), both Mid-life (β = -0.117, p = 0.011) and Late-life (β = -0.133, p = 0.013) LEQ score significantly contributed to functional status. Our results indicate that functional status is mediated in part by cognitive lifestyle and that experiences accumulated in mid-life and late-life have a greater effect on functional status at time of diagnosis.

TOWARD AN OPERATIONAL DEFINITION OF COGNITIVE LIFESTYLE: MODELING RESERVE ACROSS THE LIFESPAN

A recent systematic review of current definitions of cognitive reserve across the lifespan was undertaken by our group and five reserve constructs were identified: Educational attainment, sociological position, occupational complexity, cognitive ability, and engagement in leisure activities. The aim of this study was to test whether the different constructs are predictive of cognitive performance in older adults. A theoretical model of cognitive lifestyle was designed to assess reserve across the lifespan and the different measures were mapped in individuals aged >=65 years (N=7,762; 54.47% women) from the Cognitive Function and Ageing Study (CFAS II). Multivariable logistic regression analyses, controlling for age and sex, were used to determine the relationship between later life cognitive function and the five identified measures of reserve. In support of previous findings, the results show that risk of cognitive decline decreases with additional education (OR=0.89; 95% CI= 0.86, 0.94), increasing fluid intelligence (OR=1.00; 95% CI= 0.99, 1.00), and participation in leisure activities (OR= 0.27; 95% CI=0.17, 0.42), and that the lower the hierarchical position of a person’s social strata, the greater their odds of cognitive impairment in later life (OR=1.02; 95% CI=1.00, 1.05). However, though greater occupational complexity with data (OR=1.11; 95% CI=1.03, 1.19) and with people (OR=1.10; 95% CI= 1.03, 1.19) was found to be protective of cognitive decline as expected, greater occupational complexity with things was associated with greater decline (OR=0.98; 95% CI=0.93, 1.04). Given the cross-sectional nature of the present study, further longitudinal work is needed to ascertain what is driving these results.