METHODS: We studied the relationship of education, occupational training, and appointment to a leading position with dementia in a cross-sectional study of older female members of a religious order.

RESULTS: Out of 517 eligible sisters, 442 (85.5%) with an average of 54 years membership in the order participated in the study, among which 104 cases of dementia were identified. We found a strong association of low educational and occupational attainment with dementia. The increased risk of dementia was attributable to sisters being poorly educated (age-adjusted OR = 4.5; 95% CI: 2.0-9.9), not having received any vocational training (OR = 9.1; 95% CI: 3.9-20.9), and never having been appointed to a leading position (OR = 3.7; 95% CI: 2.0-7.0).

CONCLUSION: In a setting which largely excludes the influence of lifestyle and environmental factors, we observed a strong association between educational variables and dementia. Our findings support the hypothesis of a reserve capacity against the consequences of brain diseases.

Dement Geriatr Cogn Disord. 2009;27(6):548-56. Epub 2009 Jul 8.

Bickel H, Kurz A.

Department of Psychiatry and Psychotherapy, Technische Universität München, München, Germany. h.bickel@lrz.tum.de

METHODS: More than 700 old people underwent annual clinical evaluations for up to 5 years. At baseline, they rated current and past frequency of cognitive activity with the current activity measure administered annually thereafter. Those who died underwent a uniform postmortem examination of the brain. Amyloid burden, density of tangles, and presence of Lewy bodies were assessed in eight brain regions and the number of chronic cerebral infarctions was noted.

RESULTS: During follow-up, 90 people developed AD. More frequent participation in cognitive activity was associated with reduced incidence of AD (HR = 0.58; 95% CI: 0.44, 0.77); a cognitively inactive person (score = 2.2, 10th percentile) was 2.6 times more likely to develop AD than a cognitively active person (score = 4.0, 90th percentile). The association remained after controlling for past cognitive activity, lifespan socioeconomic status, current social and physical activity, and low baseline cognitive function. Frequent cognitive activity was also associated with reduced incidence of mild cognitive impairment and less rapid decline in cognitive function. Among 102 persons who died and had a brain autopsy, neither global nor regionally specific measures of neuropathology were related to level of cognitive activity before the study, at study onset, or during the course of the study.

CONCLUSION: Level of cognitively stimulating activity in old age is related to risk of developing dementia.
Wilson RS, Scherr PA, Schneider JA, Tang Y, Bennett DA.
Rush Alzheimer’s Disease Center, Rush University Medical Center, 600 South Paulina, Suite 1038, Chicago, IL 60612, USA. rwilson@rush.edu

Neurology. 2007 Nov 13;69(20):1896-7.