seniors

A pilot study involving six patients with mild Alzheimer’s has shown using Deep Brain Stimulation (DBS) is safe and may help improve memory, or at least slow decline. Patients received continuous stimulation for 12 months, between 2005 and 2008. Impaired glucose utilization in the temporal and parietal lobes was dramatically reversed early in the treatment, and maintained after the year of continuous stimulation. Performance on cognitive tests showed possible improvement and/or slowing in the rate of cognitive decline at 6 and 12 months in three of the six patients.

Following on from indications that gum disease might be a risk factor for dementia, analysis of data from 152 subjects in the Danish Glostrop Aging Study has revealed that periodontal inflammation at age 70 was strongly associated with lower cognitive scores (on the Digit Symbol Test). Those with periodontal inflammation were nine times more likely to test in the lower range compared to those with little or no periodontal inflammation. A larger follow-up study, among a more ethnically diverse range of subjects, is planned. I hope they also plan to extend the cognitive testing.

A two-year study involving 271 older adults (70+) with mild cognitive impairment has found that the rate of brain atrophy in those taking folic acid (0.8 mg/d), vitamin B12 (0.5 mg/d) and vitamin B6 (20 mg/d), was significantly slower than in those taking a placebo, with those taking the supplements experiencing on average 30% less brain atrophy. Higher rates of atrophy were associated with lower cognitive performance. Moreover those who with the highest levels of homocysteine at the beginning of the trial benefited the most, with 50% less brain shrinkage.

A number of studies have found evidence that fruits and vegetables help fight age-related cognitive decline, and this has been thought to be due to their antioxidant and anti-inflammatory effects. A new study shows there may be an additional reason why polyphenols benefit the aging brain. One reason why the brain works less effectively as it gets older is that the cells (microglia) that remove and recycle biochemical debris not only fail to do their housekeeping work, but they actually begin to damage healthy cells.

I have often spoken of the mantra: What’s good for your heart is good for your brain. The links between cardiovascular risk factors and cognitive decline gets more confirmation in this latest finding that people whose hearts pumped less blood had smaller brains than those whose hearts pumped more blood. The study involved 1,504 participants of the decades-long Framingham Offspring Cohort who did not have a history of stroke, transient ischemic attack or dementia. Participants were 34 to 84 years old.

A number of studies have found that source memory (knowing where you heard/read/experienced something) is a particular problem for older adults. Destination memory (knowing who you’ve told) is an area that has been much less studied. Last year I reported on why destination memory is difficult for all of us (my report is repeated below). A follow-up study has found not only that destination memory is a particular problem for older adults, but that it is in fact a worse problem than source memory.

On the subject of the benefits of walking for seniors, it’s intriguing to note a recent pilot study that found frail seniors who walked slowly (no faster than one meter per second) benefited from a brain fitness program known as Mindfit. After eight weeks of sessions three times weekly (each session 45-60 minutes), all ten participants walked a little faster, and significantly faster while talking. Walking while talking requires considerably more concentration than normal walking.

A study involving 65 older adults (59-80), who were very sedentary before the study (reporting less than two episodes of physical activity lasting 30 minutes or more in the previous six months), has found that those who joined a walking group improved their cognitive performance and the connectivity in important brain circuits after a year. However, those who joined a stretching and toning group showed no such improvement. The walking program involved three 40-minute walks at a moderate pace every week.

A study involving over 180,000 older veterans (average age 68.8 at study start), of whom 29% had PTSD, has revealed that those with PTSD had a significantly greater risk of developing dementia. Over the seven years of the study, 10.6% of the veterans with PTSD developed dementia compared to 6.6% of those without PTSD. When age was used as the time scale, the risk for those with PTSD was more than double. Results were similar when those with a history of head injury, substance abuse, or clinical depression, were excluded.

Following on from previous research with mice that demonstrated that a diet rich in methionine could increase the risk of developing Alzheimer's Disease through its effect on homocysteine levels, a new study has found that these effects were reversible if the mice then switched to a healthier diet. The mice, after five months on a methionine-rich diet, were divided into two groups, with one group continuing the diet and the second switching to the healthy diet for an additional two months.