Educational attainment and mid-life stress as risk factors for dementia in late life

The prevalence of dementia doubles every 5–7 years after the age of 60–65 years, affecting approximately 50% of the population aged ∼90 years. With the continuing demographic shift towards greater longevity in developed and developing nations, the human tragedy and already huge public health burden of these diseases will be monstrous within a few decades. Effective strategies for primary and secondary prevention must be developed. To accomplish this goal, we must accurately discern the specific disease processes leading to dementia, understand their essential determinants and identify environmental factors and experiences that can be targeted for primary and secondary preventive interventions.Molecular, pathological and neuroimaging methods are being used to examine what appears to be the most important pathological processes responsible for the common dementing illnesses. Epidemiological methods are employed to define clinical features linked to specific pathogenic processes, and to identify risk factors associated with clinical illnesses, early clinical indicators, and structural and metabolic biomarkers. Despite many efforts, research to identify risk factors has been relatively disappointing. The current issue of Brain includes complementary epidemiological reports focusing on two informative but non-specific risk factors: mid-life stress and pre-morbid educational attainment.In a clearly presented report from a longitudinal community study of 1462 women, Johansson and co-workers present convincing evidence for an association between self-reported mid-life stress and an increased risk of developing dementia decades later (Johansson et al ., 2010). The authors recognize that the underlying mechanisms mediating the association cannot be determined, but suggest a number of alternatives. If, as may be the case, …