seniors

A study involving nearly 6,000 African American older adults has found those with a specific gene variant have almost double the risk of developing late-onset Alzheimer’s disease compared with African Americans who lack the variant. The size of the effect is comparable to that of the ‘Alzheimer’s gene’, APOE-e4.

The gene (ABCA7) is involved in the production of cholesterol and lipids. It also affects the transport of several important proteins, including amyloid precursor protein, which is involved in the production of amyloid-beta.

Analysis of data from 418 older adults (70+) has found that carriers of the ‘Alzheimer’s gene’, APOEe4, were 58% more likely to develop mild cognitive impairment compared to non-carriers. However, ε4 carriers with MCI developed Alzheimer’s at the same rate as non-carriers. The finding turns prevailing thinking on its head: rather than the gene increasing the risk of developing Alzheimer’s, it appears that it increases the risk of MCI — and people with MCI are the main source of new Alzheimer’s diagnoses.

Analysis of eight studies on diet and stroke published between 1990 and 2012 has found that risk of first-time stroke dropped with every 7g increase in total daily fibre. That amount of fibre is contained in a bowl of wholewheat pasta plus two servings of fruit or vegetables.

Insufficient data is available to say whether soluble or insoluble fibre is better. The studies came from the United States, northern Europe, Australia, and Japan.

A 2-year trial involving 251 patients with Parkinson's disease and early motor complications (mean age, 52 years; mean duration of disease, 7.5 years) has found that those given deep brain stimulation surgery significantly improved their quality of life, motor disability, activities of daily living, levodopa-induced motor complications, and time with good mobility and no dyskinesia. Those given normal medical therapy, on the other hand, declined or at best got no worse.

Brain scans of 61 older adults (65-90), of whom 30 were cognitively healthy, 24 cognitively impaired and 7 diagnosed with dementia, found that, across all groups, both memory and executive function correlated negatively with brain infarcts, many of which had been clinically silent. The level of amyloid in the brain did not correlate with either changes in memory or executive function, and there was no evidence that amyloid interacted with infarcts to impair thinking.

A small study of “Super Agers” has found a key difference between them and typical older adults: an unusually large anterior cingulate (involved in attention), with four times as many von Economo neurons.

Scientific American article

Preliminary findings from a small study show that older adults (68-91), after learning to use Facebook, performed about 25% better on tasks designed to measure their ability to continuously monitor and to quickly add or delete the contents of their working memory (updating), compared to their baseline performance. Two other groups of 14 showed no change. The second group of 14 were taught to use a private online diary site (Penzu.com), while the third control group were told they were on a wait-list for Facebook training.