Category: Dementia

Sleep disturbance is common in dementia, but the reason is unclear.

Getting less REM sleep — the phase in which we dream — is linked to dementia, a study finds.

During sleep the brain cycles between periods of deep sleep and then up towards shallower periods of sleep in which we tend to dream, whether we remember those dreams or not.

During REM sleep the eyes move rapidly from side-to-side (hence Rapid Eye Movement Sleep).

Brain activity also increases and our pulses quicken.

Dr Matthew P. Pase, the study’s first author, said:

“Sleep disturbances are common in dementia but little is known about the various stages of sleep and whether they play a role in dementia risk.

We set out to discover which stages of sleep may be linked to dementia and while we did not find a link with deep sleep, we did with REM sleep.”

The research involved 321 people, average age 67, who were followed for 12 years.

The results showed that people who eventually developed dementia spent less time in REM sleep than those that did not.

For each 1% decrease in REM sleep, the dementia risk increased 9%.

In this study, average REM sleep for those that did not develop dementia was 20%.

For those that did develop dementia it was 17%.

Dr Pase said:

“Our findings point to REM sleep as a predictor of dementia.

The next step will be to determine why lower REM sleep predicts a greater risk of dementia.

By clarifying the role of sleep in the onset of dementia, the hope is to eventually identify possible ways to intervene so that dementia can be delayed or even prevented.”

The other stages of sleep were not linked to dementia, the researchers found.

The study was published in the journal Neurology (Pase et al., 2017).

It provides an extra layer of protection against dementias like Alzheimer’s disease.

Being married or in a close relationship almost halves the risk of developing dementia, research finds.

It is likely because those in close relationships have an extra layer of protection against depression.

Depression is a known risk factor for dementia.

Professor Eef Hogervorst, who led the study, explained it could also be down to a healthier lifestyle:

“It might be because other studies often found that married men on average have healthier lifestyles than single men – such as better diets, less alcohol, less smoking and more and earlier health services visits.

Another explanation could be that married couples will try to cope with dementia symptoms on their own for longer before health services are involved.”

The six-year study tracked 6,677 people aged between 52 and 90 to look at the connection between close relationships and Alzheimer’s disease.

It emerged that relationship quality was more important in protecting people against dementia than quantity of relationships.

Professor Hogervorst continued:

“Single people will need help to cope with their symptoms earlier.

Not being married almost doubled the risk for developing dementia.

On the other hand, having close relationships independently reduced the risk by 60%.

We did not find that social isolation per se increased risk but that feeling lonely did, by 44%.”

Along with being single, other risk factors for dementia included heart disease, hypertension, and depression.

Professor Hogervorst said:

“We know that depression and heart disease risk factors are risk factors for dementia.

And, loneliness had a similar strength of association as the heart disease risk factors.

This has been mentioned before for other morbidities where loneliness was said to be as bad for health as smoking.

We are social creatures and reduction of stress through social support may be more important than previously thought.”

Enhancing older people’s relationship quality could be one key to staving off dementia.

Professor Hogervorst said:

“Being lonely can be associated with depression and this has been associated with dementia.

As most people with dementia stay at home most of the time, we try to use technology to do activities which include others, such as modified forms of Facebook, cognitive stimulation therapy and exercises in virtual groups.”

The study was published in The Journals of Gerontology (Rafnsson et al., 2017).

At least 5 million Americans are living with Alzheimer’s.

Having moderate or severe anxiety in midlife is linked to dementia later on, research finds.

Anxiety is strongly linked to the personality trait of neuroticism, which includes sadness, irritability and self-consciousness.

The extra risk could be related to the stress caused by a mental health condition.

The stress response to anxiety could accelerate the aging process in the brain, increasing cognitive decline.

Depression has already been linked to a doubling of the risk in developing dementia.

Tackling anxiety and depression in midlife could be a way to reduce dementia risk, the study’s authors write:

“Non-pharmacological therapies, including talking therapies, mindfulness-based interventions, and meditation practices, that are known to reduce anxiety in midlife, could have a risk-reducing effect, although this is yet to be thoroughly researched.”

The study was a meta-analysis, a type of research that pools together the results of other studies.

The researchers found four large studies examining the link between dementia and anxiety that together included almost 30,000 people.

All four studies found that moderate to severe anxiety was linked to developing dementia later on.

The researchers write:

“Clinically significant anxiety in midlife was associated with an increased risk of dementia over an interval of at least 10 years.”

Dr Sara Imarisio, Head of Research at Alzheimer’s Research UK, said:

“Mental health conditions like anxiety and depression have been linked to dementia before and many overlapping symptoms make a dementia diagnosis difficult.

This review took a high-quality approach, combining findings from four existing studies exploring anxiety as a risk factor for dementia.

[…]

It’s important to remember that just because there is an association between the two factors does not necessarily mean that anxiety causes dementia.

Dementia is caused by a complex mix of risk factors including age and genetics and although this study looked at dementia in people more than ten years after being diagnosed with anxiety, we know the diseases leading to dementia can begin in the brain up to twenty years before any symptoms show.”

The study was published in the journal BMJ Open (Gimson et al., 2018).

The study included almost 350 people whose sleep and cognitive function were tracked over around two decades.

Getting only 1 percent less deep sleep each year increases the risk of dementia by 27 percent.

Maintaining or enhancing deep sleep, research suggests, could help to reduce dementia risk.

During sleep the brain cycles between periods of deep sleep and then up towards shallower periods of sleep in which we tend to dream, whether we remember or not.

Deep sleep, which occurs mostly in the first three hours of the night, is when the brain processes thoughts and memories.

Dr Matthew Pase, study co-author, said:

“Slow-wave sleep, or deep sleep, supports the aging brain in many ways, and we know that sleep augments the clearance of metabolic waste from the brain, including facilitating the clearance of proteins that aggregate in Alzheimer’s disease.

However, to date we have been unsure of the role of slow-wave sleep in the development of dementia.

Our findings suggest that slow wave sleep loss may be a modifiable dementia risk factor.”

Reduced deep sleep

The study included almost 350 people whose sleep and cognitive function were tracked over around two decades.

With age people tended to get less deep sleep, but those whose deep sleep reduced more over the years were at increased risk of developing dementia.

Dr Pase said:

“We also examined whether genetic risk for Alzheimer’s Disease or brain volumes suggestive of early neurodegeneration were associated with a reduction in slow-wave sleep.

We found that a genetic risk factor for Alzheimer’s disease, but not brain volume, was associated with accelerated declines in slow wave sleep.”

Related

• Getting less REM sleep — the phase in which we dream — is linked to dementia.
• Spending less time in deep sleep is linked to loss of brain cells and dementia.
• People who sleep for too little or too long are at a higher risk of cognitive decline and dementia.

The study was published in the journal JAMA Neurology (Himali et al., 2023).

Evidence for a major cause of dementia confirmed.

People with a higher body-mass index are more likely to develop dementia, research finds.

Being classed as overweight rather than in the normal range increases the dementia risk by 16-33%.

For a person who is 170cm (5’7″), for example, carrying an extra 14.5kg (32lbs) over the ideal weight, will increase their dementia risk between 16 and 33%.

Being classed as obese (an additional 14.5kg) adds the same amount of dementia risk again, making a total of up to 66%.

The study analysed data from 1.3 million adults in the US and Europe.

Professor Mika Kivimäki, the study’s first author, said:

“The BMI-dementia association observed in longitudinal population studies, such as ours, is actually attributable to two processes.

One is an adverse effect of excess body fat on dementia risk.

The other is weight loss due to pre-clinical dementia.

For this reason, people who develop dementia may have a higher-than-average body mass index some 20 years before dementia onset, but close to overt dementia have a lower BMI than those who remain healthy.

The new study confirms both the adverse effect of obesity as well as weight loss caused by metabolic changes during the pre-dementia stage.”

Previous studies have given conflicting messages about the effect of obesity on dementia.

Some have suggested more weight may have a protective effect, others, like this one, the reverse.

The study was published in the journal Alzheimer’s & Dementia (Kivimäki et al., 2017).

Adhering to this diet could not only lower the risk of heart disease but also boost cognitive function.

Heart healthy diets designed to lower blood pressure can also improve memory and thinking in later life.

According to a study, middle-aged women who adopt a blood pressure lowering diet are 17 percent less likely to experience signs of cognitive decline such as memory loss, poor thinking and reasoning years later.

Adhering to a healthy eating style such as the Dietary Approaches to Stop Hypertension diet (DASH) not only lowers the risk of heart disease but also can boost cognitive function.

The study focused on women as over two-thirds of people with Alzheimer’s disease are female.

Alzheimer’s is the most common type of dementia, which gradually ruins memory and thinking skills.

It is estimated that nearly 7 million Americans age 65 and older are living with Alzheimer’s disease, and the figure is likely to double by 2060.

Professor Yu Chen, the study’s senior author, said:

“Subjective complaints about daily cognitive performance are early predictors of more serious neurocognitive disorders such as Alzheimer’s.

With more than 30 years follow-up, we found that the stronger the adherence to a DASH diet in midlife, the less likely women are to report cognitive issues much later in life.”

The DASH diet

The DASH diet plan involves eating lots of fruit, vegetables and whole grains and also includes fish, poultry, non-fat or low fat dairy, nuts, seeds, legumes, and vegetable oils.

It also encourages eating foods that are high in magnesium, calcium, and potassium but limits foods that are high in cholesterol, saturated fat, sugar, salt, and sodium.

The diet is mainly designed to combat high blood pressure and so the risk of heart disease but it also improves cognitive function.

Hypertension in middle-age is also a risk factor for vascular cognitive impairment, a condition that damages the brain’s blood vessels, leading to cognitive decline, Alzheimer’s disease and other types of dementia.

Start in midlife

The study enrolled 5,116 women with a 30-year follow up.

They assessed participants’ levels of cognitive impairment, which can potentially lead to dementia in later life.

Typical cognitive issues include forgetting recent events or conversations or failing to navigate familiar roads, or remember shopping lists.

The results showed that women who consumed the DASH diet were 17 percent less likely to have such cognitive problems.

Ms Yixiao Song, the study’s first author, said:

“Our data suggest that it is important to start a healthy diet in midlife to prevent cognitive impairment in older age.”

Dr Fen Wu, study co-author, said:

“Following the DASH diet may not only prevent high blood pressure, but also cognitive issues.”

Related

• Diets containing small amounts of animal products may lower blood pressure.
• Exercise plus following the DASH diet leads to a reduction in blood pressure and weight loss.
• Drinking a low-sodium vegetable juice can quadruple weight loss.
• Eating blueberries could help improve memory and cognitive function.

The study was published in the journal Alzheimer’s & Dementia (Song et al., 2023).

In one-third of Parkinson’s patients these hallucinations manifest themselves before the characteristic trembling.

Experiencing minor hallucinations, such as feeling someone is nearby when there is no one there, could be an early sign of Parkinson’s disease, a study finds.

Known as ‘presence hallucinations’, they are also occasionally felt by healthy people, but can be an early indicator of neurological dysfunction.

In Parkinson’s disease — which is chiefly known for producing tremors — hallucinations like these can predict more rapid cognitive decline and tend to appear early on.

Other minor hallucinations sometimes experienced by those with Parkinson’s include passage hallucinations, which consist of a fleeting glance of someone or something passing sideways and other visual hallucinations, such as mistaking a table for a dog.

Parkinson’s is often diagnosed too late — early interventions can help to slow the progression of the disease, so minor hallucinations could be a useful warning sign.

Professor Olaf Blanke, study co-author, said:

“We now know that early hallucinations are to be taken seriously in Parkinson’s disease.

If you have Parkinson’s disease and experience hallucinations, even minor ones, then you should share this information with your doctor as soon as possible.

So far, we only have evidence linking cognitive decline and early hallucinations for Parkinson’s disease, but it could also be valid for other neurodegenerative diseases.”

Decaying cognitive function

The study included 75 people, aged between 60 and 70 who had Parkinson’s disease.

The results showed that those with early hallucinations were more likely to display cognitive decline in executive function — the ability to plan and control behaviour.

Regular hallucinations are experienced by half of Parkinson’s patients, despite being a little-known symptom.

In one-third of patients hallucinations manifest themselves before the characteristic trembling.

Professor Blanke said:

“Detecting the earliest signs of dementia means early management of the disease, allowing us to develop improved and personalized therapies that try to modify the course of the disease and improve cognitive function.”

While presence hallucinations can be relatively minor at first, they may progress to more complex visual hallucinations later on.

Professor Blanke said:

“We aim to have an early marker to identify individuals at risk of a more severe form of Parkinson’s disease, characterized by a more rapid cognitive decline and dementia, based on hallucinations proneness.

And ideally identify those individuals even before hallucinations actually occur.

We are therefore developing neurotechnology methods and procedures for that purpose.”

Related

• A reduction in serotonin function is an early sign of Parkinson’s disease.
• Small changes to handwriting can be the first sign of Parkinson’s disease.
• Constipation is an early sign of Parkinson’s disease

The study was published in the journal Nature Mental Health (Bernasconi et al., 2023).

Inadequate daily intake of this vitamin-like compound can lead to an enlarged heart, liver damage, weight gain as well as Alzheimer’s disease.

A deficiency in choline is linked to increased Alzheimer’s risk, research finds.

Choline is a vitamin-like essential nutrient produced in the liver, however, the amounts produced are too small for the body’s requirements.

Lecithin (a fatty substance) is the main source of choline found in egg yolk, beef, fish, chicken, wheat germ, soy beans, dairy products, peanuts, and almonds.

Choline is well known for its effect in treating memory disorders such as Alzheimer’s disease and dementia.

According to the US Institute of Medicine the minimum daily intake of choline for men is 550mg and 425mg for women.

Pregnant and breastfeeding women require at least 450mg and 550mg choline per day respectively, due to the crucial role of this nutrient in infant development.

Despite these daily requirements, national dietary surveys have found that less than 10 percent of Americans are meeting the recommendations.

Essential for brain health

Choline is not only essential for brain health but also influences liver function as shortfalls in this nutrient can cause cell damage and irregularities in fat metabolism.

A study has examined how choline deficiency can adversely influence the brain, liver, and heart.

The research team found that dietary choline deficiency in mice led to weight gain, reduced glucose metabolism, enlargement of the heart, neurological alterations, and liver damage.

Choline deficiency also led to elevated levels of tau tangles and beta-amyloid plaques, two key features of Alzheimer’s disease.

Amyloid plaques are clustered proteins between the nerve cells and tau tangles are abnormal accumulations of tau proteins inside neurons.

Dr Ramon Velazquez, the study’s senior author, pointed out that choline deficiency in human contains two aspects:

“it’s a twofold problem.

First, people don’t reach the adequate daily intake of choline established by the Institute of Medicine in 1998.

And secondly, there is vast literature showing that the recommended daily intake amounts are not optimal for brain-related functions.”

The study shows a link between choline deficiency and a group of neurological and physical changes.

Adequate levels of choline, on the other hand, will improve overall health and protect the nervous system.

For example, elevated levels of homocysteine have been found to to be neurotoxic and associated with neurodegenerative diseases but choline can reduce homocysteine levels.

Another example is that acetylcholine a neurotransmitter synthesized from choline which is vital for cognitive functions including learning, memory, and attention.

These findings support other studies concerning the influence of dietary choline on human health.

The evidence may help people, particularly vegans and those on plant-based diets, to eat foods rich in choline.

The authors also explored proteins in the hippocampus, one of the brain areas wracked by Alzheimer’s.

Inadequate choline status appeared to affect hippocampal networks associated with postsynaptic membrane regulation and microtubule function — the two are vital for functions of the brain.

In addition, blood plasma samples revealed that choline deficiency caused alterations in certain proteins produced in the liver which are important for metabolic function.

Dr Velazquez said:

“Our work provides further support that dietary choline should be consumed on a daily basis given the need throughout the body.”

The study was published in the journal Aging Cell (Dave et al., 2023).