Lifestyle and the aging brain: interactive effects of modifiable lifestyle behaviors and cognitive ability in men from midlife to old age.

We examined the influence of lifestyle on brain aging after nearly 30 years, and tested the hypothesis that young adult general cognitive ability (GCA) would moderate these effects. In the community-dwelling Vietnam Era Twin Study of Aging (VETSA), 431 largely non-Hispanic white men completed a test of GCA at mean age 20. We created a modifiable lifestyle behavior composite from data collected at mean age 40. During VETSA, MRI-based measures at mean age 68 included predicted brain age difference (PBAD), Alzheimer's disease (AD) brain signature, and abnormal white matter scores. There were significant main effects of young adult GCA and lifestyle on PBAD and the AD signature (ps ≤ 0.012), and a GCA-by-lifestyle interaction on both (ps ≤ 0.006). Regardless of GCA level, having more favorable lifestyle behaviors predicted less advanced brain age and less AD-like brain aging. Unfavorable lifestyles predicted advanced brain aging in those with lower age 20 GCA, but did not affect brain aging in those with higher age 20 GCA. Targeting early lifestyle modification may promote dementia risk reduction, especially among lower reserve individuals.

Assessing accuracy of non-eye care professionals as trainee vision screeners for children.

OBJECTIVE: To determine the level of agreement between non-eye care trainees and a trainer (ophthalmologist) in a vision screening program. DESIGN: Prospective, observational study carried out in 3 phases (Phase I-III). PARTICIPANTS: Study population included 1228 children, aged 6-14 years, at 5 elementary schools in the city of Hamilton. METHODS: In Phase I, 1228 children were screened by the trainee screeners, of which 273 children failed the vision testing. Of these 273 children, 170 consented to enrolment into Phase II and were examined by an ophthalmologist, who confirmed that 105 of these children were true positives. On retesting (Phase III), the ophthalmologist passed 158 of the 163 randomly selected children who passed in Phase I. RESULTS: Overall, trainee screeners had a sample sensitivity of 95.5% and sample specificity of 70.8% in detecting children who should fail vision screening. When we used the positive and negative prediction values obtained, 198 of the 1228 children had vision impairment-providing an estimated prevalence of 16.1%, or 161 children per 1000 population. CONCLUSIONS: Non-eye care professionals can be trained to an acceptable degree of accuracy to perform certain vision screening tests on children. Such screening methods may be a useful approach to address existing gaps in provision of eye care for many Canadian children, thereby ensuring that all children receive timely vision screening.