Bauermeister, S.D., ,
British Medical Journal (2023)
DOI: https://doi.org/10.1177/0271678X231173587
Summary
This study sought to look at the relationship between pre-diabetes (that is resistance of the body tissue to insulin), depressive symptoms and performance on memory tests in 40-59 year olds. Blood samples were analysed to check how responsive the body tissues were to insulin. Scores on a depression symptoms scale was used to assess levels of depression. Results from two computerised tests were used to determine memory and thinking skills. The results found those with evidence of insulin resistance reported higher depression symptoms. Higher insulin resistance in older middle-aged adults may be particularly detrimental to some aspects of memory and thinking as performance was impaired in those aged 50-60 years. The findings show that there are interrelationships between depression, resistance to insulin and cognitive impairment.
Maria-Eleni Dounavi , Elijah Mak, Peter Swann, Audrey Low, Graciela Muniz-Terrera, Anna McKeever,
Marianna Pope, Guy B Williams, Katie Wells, Brian Lawlor, Lorina Naci, Paresh Malhotra, Clare Mackay, Ivan Koychev, Karen Ritchie, Li Su, Craig W Ritchie and John T O’Brien.
Journal of Cerebral Blood flow & Metabolism (2023)
DOI: https://doi.org/10.1177/0271678X231173587
Summary
Timely delivery of oxygen and nutrients to the brain via the bloodstream is crucial for the maintenance of brain health. Using a brain imaging technique called arterial spin labelling (ASL) we can measure the delivery of blood to the brain tissue to quantify cerebral blood flow (CBF). In the present study we examined differences in blood flow between people who carry at least one copy of the apolipoprotein ε4 (APOE4) gene (potential higher risk for future Alzheimer’s disease) and those who do not carry any copy of APOE4. We also examined the relationship between different sizes and shapes of red blood cells and cerebral blood flow.
APOE4 carriers demonstrated an unexpected pattern of higher cerebral blood flow in their brain. We have also found that the relationship between CBF and size and shape of red blood cells is different between APOE4 carriers and non-carriers, especially in areas that are far from the arteries supplying blood to the brain.
Graham M. Farina F, Ritchie C, Lawlor B, Naci L.
Cambridge Quarterly of Healthcare Ethics. 31: 4, 498–505 (2022)
DOI: https://doi.org/10.1017/S0963180122000408
Summary
A general obligation to make aggregate research results available to participants has been widely supported in the bioethics literature. However, dementia research presents several challenges to this perspective, particularly because of the fear associated with developing dementia. The authors argue that considerations of respect for persons, beneficence, and justice fail to justify an obligation to make aggregate research results available to participants in dementia research. Nevertheless, there are positive reasons in favor of making aggregate research results available; when the decision is made to do so, it is critical that a clear strategy for communicating results is developed, including what support will be provided to participants receiving aggregate research results.
Amy Heneghan, Feng Deng, Katie Wells, Karen Ritchie, Graciela Muniz-Terrera , Craig W Ritchie, Brian Lawlor, Lorina Naci.
Journal of Alzheimer’s Disease (2022).
DOI: 10.3233/JAD-220267
Summary
Mid-life lifestyle factors, including occupation, as well as engagement in physical, social and intellectual activities were evaluated. The impact of risk and protective lifestyle factors was measured in three aspects of cognition, verbal and visual memory, visual short-term memory and visuospatial function. Lifestyle activities significantly impacted cognition in mid-life. More frequent engagement in physically, socially and intellectually stimulating activities was associated with better verbal and visual memory, both at baseline and at follow-up. Critically, a significant association was also found between family history of dementia with lifestyle and visuospatial function, at follow-up. Impaired visuospatial function is one of the earliest cognitive deficits in AD. These findings suggest that modifiable lifestyle activities may offset AD risk-related cognitive decrements in mid-life, and support the targeting of stimulating lifestyle activities for the prevention of Alzheimer’s Disease.
Maria-Eleni Dounavi, Audrey Low, Graciela Muniz Terrera, Karen Ritchie, Craig W. Ritchie, Li Su, Hugh S. Markus, John T O’Brien.
Brain Communications (2022)
DOI: https://academic.oup.com/braincomms/article/4/3/fcac116/6580683
Summary
Structural brain magnetic resonance imaging scans are typically used to measure properties of brain areas such as their volume or thickness. However, the intensity values of the acquired scans, can further be analysed and ‘texture’ can be quantified. Textural analysis examines variations in the image intensity and quantifies properties such as homogeneity or contrast of the image at a regional level. In this study we have measured textural properties of brain scans from PREVENT-Dementia participants and investigated if these were connected to performance in a reaction time task, to a marker of cerebrovascular pathology (white matter hyperintensity -WMH volume) and to a cardiovascular dementia risk score (CAIDE). Our findings suggest that textural measures might capture subtle underlying damage in normal appearing brain areas and could be more sensitive measures of early changes compared to WMH volume.
