The Longevity Project » dementia

Education, occupation, and dementia: the Bavarian school sisters study

TLP — Sat, 05 Feb 2011 18:35:56 +0000

BACKGROUND/AIMS: An inverse association of educational level with the occurrence of dementia has been repeatedly demonstrated. The mechanism of this relationship is not yet clear. Studies on populations with different educational and occupational levels but uniform living conditions throughout adult life may serve as a natural experiment and may help to rule out lifestyle and environmental factors as possible explanations.

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

Relation of cognitive activity to risk of developing Alzheimer disease

TLP — Mon, 29 Nov 2010 16:22:54 +0000

BACKGROUND: Frequent cognitive activity in old age has been associated with reduced risk of Alzheimer disease (AD), but the basis of the association is uncertain.

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.

Dietary patterns and risk of dementia: the Three-City cohort study

TLP — Thu, 17 Jan 2008 18:20:11 +0000

BACKGROUND: Dietary fatty acids and antioxidants may contribute to decrease dementia risk, but epidemiologic data remain controversial. The aim of our study was to analyze the relationship between dietary patterns and risk of dementia or Alzheimer disease (AD), adjusting for sociodemographic and vascular risk factors, and taking into account the ApoE genotype. METHODS: A total of 8,085 nondemented participants aged 65 and over were included in the Three-City cohort study in Bordeaux, Dijon, and Montpellier (France) in 1999-2000 and had at least one re-examination over 4 years (rate of follow-up 89.1%). An independent committee of neurologists validated 281 incident cases of dementia (including 183 AD). RESULTS: Daily consumption of fruits and vegetables was associated with a decreased risk of all cause dementia (hazard ratio [HR] 0.72, 95% CI 0.53 to 0.97) in fully adjusted models. Weekly consumption of fish was associated with a reduced risk of AD (HR 0.65, 95% CI 0.43 to 0.994) and all cause dementia but only among ApoE epsilon 4 noncarriers (HR 0.60, 95% CI 0.40 to 0.90). Regular use of omega-3 rich oils was associated with a decreased risk of borderline significance for all cause dementia (HR 0.46, 95% CI 0.19 to 1.11). Regular consumption of omega-6 rich oils not compensated by consumption of omega-3 rich oils or fish was associated with an increased risk of dementia (HR 2.12, 95% CI 1.30 to 3.46) among ApoE epsilon 4 noncarriers. CONCLUSION: Frequent consumption of fruits and vegetables, fish, and omega-3 rich oils may decrease the risk of dementia and Alzheimer disease, especially among ApoE epsilon 4 noncarriers.

1: Neurology. 2007 Nov 13;69(20):1921-30.

Barberger-Gateau P, Raffaitin C, Letenneur L, Berr C, Tzourio C, Dartigues JF, AlpÃ©rovitch A.

INSERM, U593, University Victor Segalen Bordeaux 2, case 11, 146 rue LÃ©o-Saignat, F-33076 Bordeaux cedex, France. Pascale.Barberger-Gateau@isped.u-bordeaux2.fr