New research uncovers factors that can protect against cognitive decline and dementia

Research at the Alzheimer’s Association International Conference 2016 in Toronto, finds that certain genes and lifestyle factors can increase resilience against the development of Alzheimer’s disease.

These resilience factors may differ between men and women and may counteract the negative effects of a poor diet on cognition.

Factors such as the number of years spent in education, having a complex job and regularly doing activities that challenge the brain can contribute to resilience by helping to build up a ‘cognitive reserve’. Cognitive reserve is the ability of the brain to withstand certain levels of damage without any loss of function.

Dr Doug Brown, Director of Research and Development at Alzheimer’s Society,said:

'Dementia is not an inevitable part of getting old. Increasingly, research is showing us that there are things we can do throughout our lives to reduce the likelihood of developing dementia.

'This research builds on what we already know about the importance of keeping our brains active to improve memory and thinking as we age, whether this is through having a complex job or hobbies and pastimes that challenge the brain and keep you connected to friends and family.

'These findings reinforce the powerful message that we should be taking a lifelong approach to maintaining good brain health. Over the next 10 years, Alzheimer’s Society is committing more than £150 million to research to not only find a cure for dementia, but ways to prevent it developing in the first place.'


A stimulating lifestyle may protect the brain from the negative effects of a poor diet

Keeping mentally active through education, a complex job, and socialising may protect against the effects of poor diet on a person’s risk of dementia, according to research to be presented at AAIC 2016 (Monday 26 July).

Researchers from Baycrest Health Sciences, Toronto, scored 351 older adults living alone in Canada on how closely they followed a ‘Western’ diet, characterised by lots of red meat, processed and sugary foods, white bread and potatoes. Participants were also given a score of ‘cognitive reserve’ based on their academic achievements, job complexity, and social habits to indicate how stimulating their lifestyle is.

Over three years, those who ate a Western diet showed accelerated rates of cognitive decline, but this was only true among those with a low cognitive reserve score (182 people). The Western diet did not appear to have a negative effect on cognitive performance in those who led a stimulating lifestyle (169 people).

Dr Doug Brown, Director of Research and Development at Alzheimer’s Society, said:

'People who regularly challenge their brains through education, work and leisure activities tend to have lower rates of dementia in later life. This study broadens out our understanding to suggest these activities could help to protect the brain by compensating against the negative impact of an unhealthy diet.

'This shouldn’t become an excuse to continue eating stodgy and sugary foods, though. Getting a healthy balanced diet that’s low in red meat and high in fruit and veg is still one of the best ways to reduce your risk of dementia throughout life.'

Reference: Matthew Parrot, PhD, et al. Indicators of Cognitive Reserve May Moderate the Adverse Relationship Between Poor Diet Quality and Cognitive Decline in Independent Older Adults: The Nuage Study.


Social jobs may provide greater protection against dementia-related damage to the brain

Research from the Wisconsin Alzheimer's Disease Research Center and Wisconsin Alzheimer’s Institute presented at AAIC 2016 finds that people with more complicated or mentally challenging jobs are better able to withstand damage to the brain associated with Alzheimer’s disease. The results suggest that working with people, rather than with data or physical things, provides the greatest protective effect.

Brain scans from 284 healthy older people who were at risk but did not have dementia were assessed for white matter hyperintensities (WMH) – which indicate damage in the brain and are commonly associated with Alzheimer’s disease. The researchers then compared this with the participants’ cognitive function and the types of work they do, or have done in the past.

People with more complex jobs throughout their lives tended to have more WMHs but were still able to perform as well as their peers on cognitive tests. These findings suggest that those with complex occupations may be better able to tolerate damage to the brain without seeing any deterioration in their cognitive abilities. This number of WMHs was most pronounced in those who worked primarily with other people, rather than with data or with things.

Dr Doug Brown, Director of Research and Development at Alzheimer’s Society, said:

'Everyone’s brains experience some wear and tear as they get older – in some people this will go unnoticed but for others it can contribute to the development of cognitive decline and dementia. This study suggests that complex jobs involving working with others might help to make people more resilient to the damage so that they are less likely to develop problems with memory and thinking.

'It’s incredibly positive to see that there are things we can do in life that could help our brains as they age. For many of us, the complexity of our job is not something we can easily change, so we need to see more research into other ways for people to build up their resilience to dementia.'

Reference: Elizabeth Boots, BS, and Ozioma Okonkwo, PhD, et.al. Occupational Complexity, Cognitive Reserve, and White Matter Hyperintensities: Fidnings from the Wisconsin Registry for Alzheimer’s Prevention.


Different lifestyle and environmental factors may protect against the effects of Alzheimer’s risk genes in men and women

Results from the Victoria Longitudinal Study in Western Canada have identified lifestyle and environmental factors that may help to protect against the effects of the Alzheimer’s disease risk genes Apolipoprotein E (APOE) ɛ4 and Clusterin (CLU) C.

Researchers followed 642 people aged 53-95 without dementia over a nine-year period. Participants were tested for APOEɛ4 or CLU-C risk genes and had regular tests to determine if their memory had declined or stayed stable over the nine years.

Researchers found that for women with one of both of the risk genes better lung function, walking speed, and socialising were linked to stable memory performance. For men, lack of depression was an important factor.

For both men and women, those with stable memory performance were more likely to: have spent longer in education; have better muscle tone; and do mentally challenging, everyday activities, such as playing bridge or doing taxes, than those who experienced memory decline.

Dr Doug Brown, Director of Research and Development at Alzheimer’s Society, said:

'One of the most common questions people ask is whether dementia is inherited. Unfortunately, there isn’t a simple answer to this - because a family member has dementia doesn’t always mean you will develop it too. This study shows that genetics can only give us part of the picture when it comes to the causes of memory loss.

'Over two thirds of people with dementia are women, and we don’t yet fully understand why men and women develop dementia at different rates. This study provides important insights into how lifestyle factors can interact with genetics to affect men and women’s memory differently. Advances like this may ultimately help us to develop gender-specific advice for those at risk of Alzheimer’s disease.'

Reference: Kirstie McDermott, BSc, et.al. Memory Resilience in Carriers of Alzheimer’s Genetic Risk: Predictors Vary for Female and Male Older Adults.


Potential new Alzheimer’s disease resilience gene identified

New research presented at AAIC 2016 conference has uncovered a new gene that might protect against Alzheimer’s disease.

Researchers from Brigham Young University, Utah State University, the University of Utah and the Washington University School of Medicine, identified families with a large number of cases of Alzheimer’s disease. Family members with dementia and those who were considered ‘resilient’ (who had normal cognition over the age of 75) were selected to have their entire genome sequenced.

A gene called RAB10 was identified as being linked to resilience against Alzheimer’s disease. In laboratory experiments, RAB10 was found to play a role in regulating the production of beta-amyloid – a protein that builds up in clumps in the brains of people with Alzheimer’s disease. 

Dr Doug Brown, Director of Research and Development at Alzheimer’s Society, said:

'We already know of more than 20 genes that increase your risk of developing Alzheimer’s disease, but this study has found a gene that seems to have the opposite effect.

'The genetic contributions to Alzheimer’s disease are incredibly complex – in most cases, genes alone don’t cause dementia and their effects should be considered alongside environmental and lifestyle factors.

'As this gene can influence the production of beta-amyloid – a toxic protein that builds up in the brains of people with Alzheimer’s disease –it could become a potential target for future Alzheimer’s treatments.'

Reference: Keoni Kauwe, PhD, et.al. Linkage and Whole Genome Sequence Analysis of AD Resilience and Risk.