Cohort differences in disease and disability in the young-old: Findings from the MRC Cognitive Function and Ageing Study (MRC-CFAS)

Background: Projections of health and social care need are highly sensitive to assumptions about cohort trends in health and disability. We use a repeated population-based cross-sectional study from the Cambridgeshire centre of the UK Medical Research Council Cognitive Function and Ageing Study to investigate trends in the health of the young-old UK population Methods: Non-overlapping cohorts of men and women aged 65–69 years in 1991/2 (n = 689) and 1996/7 (n = 687) were compared on: self-reported diseases and conditions; self-rated health; mobility limitation; disability by logistic regression and four-year survival by Cox Proportional Hazards Regression models, with adjustments for differences in socio-economic and lifestyle factors. Results: Survival was similar between cohorts (HR: 0.91, 95% CI: 0.62 to 1.32). There was a significant increase in the number of conditions reported between cohorts, with more participants reporting 3 or more conditions in the new cohort (14.2% vs. 10.1%). When individual conditions were considered, there was a 10% increase in the reporting of arthritis and a significant increase in the reporting of chronic airways obstruction (OR: 1.36, 95% CI: 1.04 to 1.78). Conclusion: This study provides evidence of rising levels of ill-health, as measured by the prevalence of self-reported chronic conditions, in the newer cohorts of the young-old. Though changes in diagnosis or reporting of disease cannot, as yet, be excluded, to better understand whether our findings reflect real increases in ill-health, investment should be made into improved population-based databases, linking self-report and objective measures of health and function, and including those in long-term care

Population variation in oxidative stress and astrocyte DNA damage in relation to Alzheimer-type pathology in the ageing brain

Increasing evidence suggests a role for oxidative damage to DNA in brain ageing and in neurodegenerative disorders, including Alzheimer's disease. Most studies have focussed on the reduced capacity for DNA repair by neurones, and have not taken into account the effect of oxidative stress on astrocytes, and their contribution to pathology

The presence of behavioural and psychological symptoms and progression to dementia in the cognitively impaired older population

Behavioural and psychological symptoms (BPS) are common in the older population and may be an indication of early dementia. We explored the predictive effect of the presence of BPS on the 2-year progression to dementia in a cognitively impaired population aged 65 years and over without dementia at baseline

Hippocampal tau pathology is related to neuroanatomical connections: an ageing population-based study

Deposits of abnormally phosphorylated tau protein are found in numerous neurodegenerative disorders; the 'tauopathies', which include Alzheimer's and Pick's diseases, but tau pathology is also found in the ageing brain. Variation in tau pathology in brain ageing and its relationship to development of tauopathies and cognitive impairment remains unclear. We aimed to determine the extent and pattern of spread of tau pathology in the hippocampus, a susceptible region important in dementia and milder states of memory impairment, using hippocampal samples from the elderly population-based Medical Research Council Cognitive Function and Ageing Study neuropathology cohort. Tau deposition was assessed in hippocampal anatomical sub-regions using the AT8 antibody to phosphorylated tau and isoform-specific antibodies to 3 and 4-repeat tau (RD3 and RD4). Abeta pathology was also assessed. In this population sample, which includes the full ageing spectrum from individuals with no cognitive impairment to those with dementia satisfying clinico-pathology criteria for Alzheimer's disease, we have demonstrated a high prevalence at death of tau pathology. AT8, Abeta, RD3 and RD4 showed similar regional distribution and increased RD3 was noted in late-stage ghost tangles. Abeta was shown to be a poor explanatory variable for tau pathology. Tau deposition progressed in a hierarchical manner. Hippocampal input regions and projection zones (such as lateral entorhinal cortex, CA1/subiculum border and outer molecular layer of dentate) were initially affected, with anterograde progression though the hippocampal circuitry. Six hippocampal tau anatomical stages were defined, each linking projectionally to their adjacent stages, suggesting spread of tau malfunction through neuroanatomical pathways in hippocampal ageing. These stages were significantly associated with dementia, and may provide a clinically useful tool in the clinico-pathological assessment of dementia and mild cognitive impairment