Gene variant may protect memory and thinking skills in older people

A study involving 200 older adults (70+) experiencing a stay in hospital has found that at discharge nearly a third (31.5%) had previously unrecognized low cognitive function (scoring below 25 on the MMSE if high-school-educated, or below 18 if not). This impairment had disappeared a month later for more than half (58%).The findings are consistent with previous research showing a lack of comprehension of discharge instructions, often resulting in rehospitalization.

A study involved 117 older adults (mean age 78) found those at greater risk of coronary artery disease had substantially greater risk for decline in verbal fluency and the ability to ignore irrelevant information. Verbal memory was not affected.

The findings add to a growing body of research linking cardiovascular risk factors and age-related cognitive decline, leading to the mantra: What’s good for the heart is good for the brain.

Adding to the growing evidence that social activity helps prevent age-related cognitive decline, a longitudinal study involving 1,138 older adults (mean age 80) has found that those who had the highest levels of social activity (top 10%) experienced only a quarter of the rate of cognitive decline experienced by the least socially active individuals (bottom 10%). The participants were followed for up to 12 years (mean of 5 years).

From the Whitehall II study, data involving 5431 older participants (45-69 at baseline) has revealed a significant effect of midlife sleep changes on later cognitive function. Sleep duration was assessed at one point between 1997 and 1999, and again between 2002 and 2004. A decrease in average night’s sleep from 6, 7, or 8 hours was significantly associated with poorer scores on tests of reasoning, vocabulary, and the MMSE. An increase from 7 or 8 hours (but not from 6 hours) was associated with lower scores on these, as well as on tests of phonemic and semantic fluency.

What makes one person so much better than another in picking up a new motor skill, like playing the piano or driving or typing? Brain imaging research has now revealed that one of the reasons appears to lie in the production of a brain chemical called GABA, which inhibits neurons from responding.

A study involving 614 middle-aged vineyard workers has found that those who were exposed to pesticides were five times as likely to perform more poorly on cognitive tests compared to those not exposed, and twice as likely to show cognitive decline over a two-year period.

A study involving 125 younger (average age 19) and older (average age 69) adults has revealed that while younger adults showed better explicit learning, older adults were better at implicit learning. Implicit memory is our unconscious memory, which influences behavior without our awareness.

A review of 23 longitudinal studies of older adults (65+) has found that small amounts of alcohol were associated with lower incidence rates of overall dementia and Alzheimer dementia, but not of vascular dementia or age-related cognitive decline. A three-year German study involving 3,327 adults aged 75+ extends the evidence to the older-old.

Comparison of young adults (mean age 24.5) and older adults (mean age 69.1) in a visual memory test involving multitasking has pinpointed the greater problems older adults have with multitasking. The study involved participants viewing a natural scene and maintaining it in mind for 14.4 seconds. In the middle of the maintenance period, an image of a face popped up and participants were asked to determine its sex and age. They were then asked to recall the original scene.

The new label of ‘metabolic syndrome’ applies to those having three or more of the following risk factors: high blood pressure, excess belly fat, higher than normal triglycerides, high blood sugar and low high-density lipoprotein (HDL) cholesterol (the "good" cholesterol). Metabolic syndrome has been linked to increased risk of heart attack.