seniors

Alzheimer's expressed differently in carriers and noncarriers of the Alzheimer’s gene

July, 2010
  • A new study reveals that having the 'Alzheimer's gene' doesn't simply increase your risk of developing Alzheimer's, but affects how the brain is damaged.

A comprehensive study reveals how the ‘Alzheimer's gene’ (APOE ε4) affects the nature of the disease. It is not simply that those with the gene variant tend to be more impaired (in terms of both memory loss and brain damage) than those without. Different parts of the brain (and thus different functions) tend to be differentially affected, depending on whether the individual is a carrier of the gene or not. Carriers displayed significantly greater impairment on tests of memory retention, while noncarriers were more impaired on tests of working memory, executive control, and lexical access. Consistent with this, carriers showed greater atrophy in the mediotemporal lobe, and noncarriers greater atrophy in the frontoparietal area. The findings have implications both for diagnosis and treatment.

Reference: 

Source: 

Topics: 

tags development: 

tags memworks: 

tags problems: 

Animal studies indicate caffeine may slow dementia and cognitive decline but human studies less conclusive

July, 2010
  • Several recent studies and reviews suggest that the benefits of caffeine for age-related cognitive impairment and dementia are limited. It may be that the association only exists for women.

A special supplement in the Journal of Alzheimer's Disease focuses on the effects of caffeine on dementia and age-related cognitive decline. Here are the highlights:

A mouse study has found memory restoration and lower levels of amyloid-beta in Alzheimer’s mice following only 1-2 months of caffeine treatment. The researchers talk of “ a surprising ability of moderate caffeine intake to protect against or treat AD”, and define moderate intake as around 5 cups of coffee a day(!).

A review of studies into the relation between caffeine intake, diabetes, cognition and dementia, concludes that indications that coffee/caffeine consumption is associated with a decreased risk of Type 2 diabetes and possibly also with a decreased dementia risk, cannot yet be confirmed with any certainty.

A study involving 351 older adults without dementia found the association between caffeine intake and cognitive performance disappeared once socioeconomic status was taken into account.

A study involving 641 older adults found caffeine consumption was significantly associated with less cognitive decline for women only. Supporting this, white matter lesions were significantly fewer in women consuming more than 3 units of caffeine per day (after adjustment for age) than in women consuming less.

A Portuguese study involving 648 older adults found that caffeine intake was associated with a lower risk of cognitive decline in women, but not significantly in men.

A review of published studies examining the relation between caffeine intake and cognitive decline or dementia shows a trend towards a protective effect of caffeine, but because of the limited number of epidemiological studies, and the methodological differences between them, is unable to come up with a definitive conclusion.

A review of published epidemiological studies looking at the association between caffeine intake and Parkinson’s Disease confirms that higher caffeine intake is associated with a lower risk of developing Parkinson’s Disease (though this association may be stronger for men than women). Other studies provide evidence of caffeine’s potential in treatment, improving both the motor deficits and non-motor symptoms of Parkinson’s.

Reference: 

Arendash, G.W. & Cao, C. Caffeine and Coffee as Therapeutics Against Alzheimer’s Disease. Journal of Alzheimer's Disease, 20 (Supp 1), 117-126.
Biessels, G.J. Caffeine, Diabetes, Cognition, and Dementia. Journal of Alzheimer's Disease, 20 (Supp 1), 143-150.
Kyle, J., Fox, H.C. & Whalley, L.J. Caffeine, Cognition, and Socioeconomic Status. Journal of Alzheimer's Disease, 20 (Supp 1), 151-159.
Ritchie, K. et al. Caffeine, Cognitive Functioning, and White Matter Lesions in the Elderly: Establishing Causality from Epidemiological Evidence. Journal of Alzheimer's Disease, 20 (Supp 1), 161-161
Santos, C. et al. Caffeine Intake is Associated with a Lower Risk of Cognitive Decline: A Cohort Study from Portugal. Journal of Alzheimer's Disease, 20 (Supp 1), 175-185.
Santos, C. et al. Caffeine Intake and Dementia: Systematic Review and Meta-Analysis. Journal of Alzheimer's Disease, 20 (Supp 1), 187-204.
Costa, J. et al. Caffeine Exposure and the Risk of Parkinson’s Disease: A Systematic Review and Meta-Analysis of Observational Studies. Journal of Alzheimer's Disease, 20 (Supp 1), 221-238.
Prediger, R.D.S. Effects of Caffeine in Parkinson’s Disease: From Neuroprotection to the Management of Motor and Non-Motor Symptoms. Journal of Alzheimer's Disease, 20 (Supp 1), 205-220.

Source: 

Topics: 

tags development: 

tags lifestyle: 

tags problems: 

Extending lifespan has mixed effects on learning and memory

July, 2010

Although roundworm research suggesting different effects at different ages is concerned with genetic manipulation, we may speculate that restricting your food intake is a bad idea for young adults but good for the old, while reducing sugar may be better for the young than it is for the old.

Studies on the roundworm C. elegans have revealed that the molecules required for learning and memory are the same from C. elegans to mammals, suggesting that the basic mechanisms underlying learning and memory are ancient, and that this animal can serve as a testing ground for treatments for age-related memory loss. Intriguingly, a comparison of two known regulators of longevity — reducing calorie intake and reducing activity in the insulin-signaling pathway (achieved through genetic manipulation) — has found that these two treatments produce very different effects on memory. While dietary restriction impaired memory in early adulthood, it maintained memory with age. On the other hand, reduced insulin signaling improved early adult memory performance but failed to preserve it with age. These different effects appear to be linked to expression of CREB, a protein known to be important for long-term memory. Young roundworms with defective insulin receptors had higher levels of CREB protein, while those worms genetically altered to eat less had low levels, but the level did not diminish with age. These findings add to our understanding of why memory declines with age.

Reference: 

Source: 

Topics: 

tags development: 

tags lifestyle: 

tags problems: 

Promise of drug therapy for age-related memory loss

July, 2010

Mouse studies suggest a way to reverse both normal age-related memory loss, and dementia.

Although research has so far been confined to mouse studies, researchers are optimistic about the promise of histone deacetylase inhibitors in reversing age-related memory loss — both normal decline, and the far more dramatic loss produced by Alzheimer’s. The latest study reveals that memory impairment in the aging mouse is associated with altered hippocampal chromatin plasticity, specifically with the failure of histone H4 lysine 12 acetylation, leading to a failure to initiate the gene expression program associated with memory consolidation. Restoring this acetylation leads to the recovery of cognitive abilities.

Reference: 

Source: 

Topics: 

tags development: 

tags memworks: 

tags problems: 

Test of implantable cardioverter defibrillator linked to cognitive problems

March, 2010

A study involving patients given on implantable cardioverter defibrillator (ICD) reveals that more than a third of participants had significant cognitive problems six weeks and six and 12 months after ICD surgery. Although most regained their normal abilities within 12 months, a few (10%) first developed difficulties at that point.

An implantable cardioverter defibrillator (ICD) is a small electronic device that monitors and regulates heartbeat, and many have been implanted in patients — an estimated 114,000 in the U.S. in 2006. Part of the implantation process involves ventricular defibrillation testing, which temporarily disrupts brain activity by causing a drop in blood pressure and blood flow to the brain. In a study involving 52 patients having cognitive tests several days before ICD surgery and again six weeks and six and 12 months afterwards, more than a third of participants had significant cognitive problems six weeks and six and 12 months after ICD surgery. Attention, short-term memory of visual words and objects, and auditory (spoken) words were most commonly affected. Although most patients regained their normal abilities by 12 months after surgery, a few (10%) first developed difficulties at that point. The results were unrelated to measurements of anxiety, depression and quality of life.

Reference: 

Source: 

Topics: 

tags development: 

tags problems: 

Smoking may counteract benefit of moderate drinking on stroke risk

March, 2010

A large long-running study has found that though non-smokers who consumed moderate amounts of alcohol were 37% less likely to develop stroke than non-drinkers, this association was not found among smokers.

A 12-year study following the drinking and smoking habits of 22,524 people aged 39-79 has found that in non-smokers, people who consumed moderate amounts of alcohol were 37% less likely to develop stroke than non-drinkers. This association was not found among smokers. The finding may explain the inconsistency in previous studies into the relationship between light to moderate drinking and stroke.

Reference: 

The findings were presented at the American Academy of Neurology's 62nd Annual Meeting in Toronto, April 10 - 17, 2010.

Source: 

Topics: 

tags development: 

tags lifestyle: 

tags problems: 

Why older adults remember the good times better

March, 2010

An imaging study has found differences in brain activity that explain why older adults are better at remembering positive events.

An imaging study reveals why older adults are better at remembering positive events. The study, involving young adults (ages 19-31) and older adults (ages 61-80) being shown a series of photographs with positive and negative themes, found that while there was no difference in brain activity patterns between the age groups for the negative photos, there were age differences for the positive photos. In older adult brains, but not the younger, two emotion-processing regions (the ventromedial prefrontal cortex and the amygdala) strongly influenced the memory-encoding hippocampus.

Reference: 

Source: 

Topics: 

tags development: 

tags memworks: 

tags problems: 

Fish oil supplements provide no benefit to brain power

April, 2010

The largest ever trial of fish oil supplements has found no evidence that they offer benefits for cognitive function in older people. However, neither the trial group or the placebo group showed any cognitive decline over the two-year period of the study.

The largest ever trial of fish oil supplements has found no evidence that they offer benefits for cognitive function in older people. The British study enrolled 867 participants aged 70-80 years, and lasted two years. After two years, those receiving fish oil capsules had significantly higher levels of omega-3 fatty acids in their blood than those receiving placebo capsules. However, cognitive function did not decline in either group over the period. The researchers caution that it may be that more time is needed for benefits to show.

Reference: 

Source: 

Topics: 

tags development: 

tags lifestyle: 

tags problems: 

Pages

Subscribe to RSS - seniors