A new study shows that a combination of inflammation and hypoxia activates microglia in a way that persistently weakens the connection between neurons, contributing to brain damage in conditions such as stroke and Alzheimer's disease.
New research helps explain the role of amyloid-beta plaques in the development of Alzheimer's, by finding that the prion protein known to bind strongly to small aggregates of amyloid-beta peptides, also attaches to large fibrillar clumps of amyloid-beta.
A Swedish study of some 4,000 60-year-olds has found that regular “non-exercise” physical activity such as gardening or DIY significantly reduced risk of heart attack or stroke, with those who were most active on a daily basis having a 27% lower risk of a heart attack or stroke and a 30% reduced risk of death from all causes. This was so regardless of how much regular formal exercise was taken.
A year-long study involving 424 sedentary, mobility-limited seniors aged 70-89, has found that variants in a specific gene (the ACE I/D gene) affect seniors’ ability to benefit from exercise. Physical activity intervention led to greater improvements in walking speed among ID and DD genotype carriers (29.9% and 13.7% respectively), but among II genotype carriers, health education alone led to more improvements in walking speed than physical activity intervention (20% vs. 18.5%).
Data from the American National Health and Nutrition Examination Survey (NHANES) III, involving 3,659 individuals (men aged 55+; women 65+), has found that the more muscle mass older adults have, the less likely they are to die prematurely. The findings add to the growing evidence that overall body composition — and not the widely used body mass index (BMI) — is a better predictor of mortality.
A four-year study involving 1,502 healthy older adults (50+) has found that the frequency of negative interactions with family members (not partners or children) and friends was associated with an increased risk of developing hypertension in women (but not in men). Each increase in the total average negative social interaction score was associated with a 38% increased chance of developing hypertension. Younger older women (51-64) were more affected than those 65 or older.
A study involving 74 older adults (70+), of whom 3 had mild dementia, 33 were cognitively normal and 38 had mild cognitive impairment, has found that high levels of "good" cholesterol and low levels of "bad" cholesterol correlated with lower levels of the amyloid-beta plaques in the brain (a hallmark of Alzheimer's disease).
