Category: Sleep

Dementia: The Optimal Sleep Time That Reduces Risk

Alzheimer’s is the most common form of dementia, making up 70 percent of cases.

Alzheimer’s is the most common form of dementia, making up 70 percent of cases.

People who sleep for too little or too long are at a higher risk of cognitive decline and dementia.

However, those who sleep for between 5.5 and 7.5 hours per night do not see declines in their cognitive health, even when suffering the early effects of Alzheimer’s disease.

Alzheimer’s is the most common form of dementia, making up 70 percent of cases.

Poor sleep is a common symptom of Alzheimer’s and can accelerate the progression of the disease.

Dr Brendan Lucey, the study’s first author, said:

“It’s been challenging to determine how sleep and different stages of Alzheimer’s disease are related, but that’s what you need to know to start designing interventions.

Our study suggests that there is a middle range, or ‘sweet spot,’ for total sleep time where cognitive performance was stable over time.

Short and long sleep times were associated with worse cognitive performance, perhaps due to insufficient sleep or poor sleep quality.

An unanswered question is if we can intervene to improve sleep, such as increasing sleep time for short sleepers by an hour or so, would that have a positive effect on their cognitive performance so they no longer decline?

We need more longitudinal data to answer this question.”

The study included 100 people, average age 75, most with no cognitive impairments.

Their cognitive function was tracked over almost 5 years, along with their sleep quality.

Professor David Holtzman, study co-author, explained the results:

“It was particularly interesting to see that not only those with short amounts of sleep but also those with long amounts of sleep had more cognitive decline.

It suggests that sleep quality may be key, as opposed to simply total sleep.”

People suffering sleep problems should be aware that they can be treated, said Professor Beau M. Ances, study co-author:

“I ask many of my patients, ‘How’s your sleep?’

Often patients report that they’re not sleeping well.

Often once their sleep issues are treated, they may have improvements in cognition.

Physicians who are seeing patients with cognitive complaints should ask them about their quality of sleep.

This is potentially a modifiable factor.”

The study was published in the journal Brain (Lucey et al., 2021).

This Sleep Pattern Increases Heart Disease Risk 54%

People who ignore this risk factor increase their odds of developing heart disease or stroke.

People who ignore this risk factor increase their odds of developing heart disease or stroke.

Less than seven, or more than eight hours of sleep can cause arterial stiffness leading to heart disease or stroke.

If you like to stay up late and have a drink or check your emails or watch TV and sleep until mid-morning, remember the quantity of sleep is important for your heart health.

The incidence of arterial stiffness is much lower in people who sleep seven or eight hours a night compared to those who sleep for shorter or longer hours, a study has found.

Consequently, people who sleep more than eight hours or less than seven hours are at higher risk of heart disease or stroke.

A research team measured 1,752 adults’ sleep patterns in Greece and based on duration of sleep they were divided into four groups.

The first was ‘normal’ group meaning their sleep was seven or eight hours per night, the second was the ‘short’ group meaning they slept six to seven hours nightly, the third one ‘very short’ meaning they had less than six hours sleep, and the last group ‘long’ as they had more than eight hours sleep nightly.

The results showed that participants who had more than eight hours a night were at a 39 percent higher risk of plaque build up inside the arteries and for those who slept less than six hours the odds increased to 54 percent.

This shows that duration of sleep is as important as exercise and diet for cardiovascular health.

Dr Evangelos Oikonomou, the study’s lead author, said:

“The message, based on our findings, is ‘sleep well, but not too well.’

Getting too little sleep appears bad for your health but too much seems to be harmful as well.

Unlike other heart disease risk factors such as age or genetics, sleep habits can be adjusted, and even after taking into consideration the impact of established risk factors for atherosclerosis and cardiovascular diseases — for example age, gender, obesity, smoking, hypertension, diabetes, high blood pressure and even a history of coronary artery disease — both short and long sleeping duration may act as additional risk factors.”

Plaque build-up causes the arterial walls to thicken and narrow so the blood flow in the brain and the body will decrease leading to cardiovascular disease or stroke.

Dr Oikonomou, said:

“We don’t fully understand the relationship between sleep and cardiovascular health.

It could be that sympathetic nervous system withdrawal or a slowing [of this system] that occurs during sleep may act as a recovery phase for [usual] vascular and cardiac strain.

Moreover, short sleep duration may be associated with increased cardiovascular risk factors — for example, unhealthy diet, stress, being overweight or greater alcohol consumption — whereas longer sleep duration may be associated with a less active lifestyle pattern and lower physical activity.”

How much sleep we need is related to different factors such as age.

The guidelines for adults are mostly seven to nine hours sleep a night, however, one in three American adults gets less than six hours sleep.

Studies have shown that people who sleep poorly are at greater risk of high blood pressure, heart disease, diabetes, obesity, mental health problem, and early death.

Experts say a regular six to eight hours a night is spot-on.

Dr Oikonomou, said:

“It seems that this amount of sleep may act as an additive cardioprotective factor among people living in modern western societies, and there can be other health benefits to getting sufficient and quality sleep.”

The study was presented at the American College of Cardiology’s Annual Scientific Session Together with World Congress of Cardiology, March 2020.

Waking 100 Times A Night Is Normal And May Indicate Healthy Sleep (M)

The reason for these ultra-short awakenings is partly related to memory, the researchers think.

The reason for these ultra-short awakenings is partly related to memory, the researchers think.

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Sleep: The Ideal Amount For Optimal Mental Health (M)

Disruption of deep sleep, which occurs more during the first part of the night, is linked to memory problems and the build-up of proteins in the brain that are linked to dementia.

Disruption of deep sleep, which occurs more during the first part of the night, is linked to memory problems and the build-up of proteins in the brain that are linked to dementia.

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The Best Nap Time To Boost Brain Health

The best nap time could keep your brain five years younger.

The best nap time could keep your brain five years younger.

Taking a nap of around an hour after lunch is linked to the biggest long-term boost in mental health, research suggests.

Almost 3,000 Chinese people over the age of 65 were included in the study of napping.

Around 60 percent reported taking a nap after lunch.

The researchers found that those taking an hour-long nap did the best on measures of memory and cognition.

The study’s authors explain their results:

“…a moderate-duration nap taken during the post-lunch dip is associated with better overall cognition.

Older adults who did not nap or napped longer than 90 minutes (extended nappers) were significantly more likely than those who napped for 30 to 90 minutes after lunch (moderate nappers) to have lower overall cognition scores…”

In comparison, those who took shorter naps, longer naps or no naps were cognitively older.

It worked out that people who did not nap for around an hour were cognitively five years older:

“In the final analysis, no napping, short napping, and extended napping were associated with worse overall cognition than moderate napping.

The difference in overall cognition associated with these napping groups was similar to or greater than the decline in cognition associated with a 5-year increase in age.”

Best nap time

The study is one of the first to look at the benefits of longer afternoon naps.

The benefits of short naps are already well-known, the study’s authors write:

“…the short-term benefits of brief naps (e.g., 10 minutes) are well documented in previous studies and include greater alertness and accuracy and speed when performing a number of cognitive tasks, including psychomotor performance and short-term memory…”

The study was published in the Journal of the American Geriatrics Society (Li et al., 2016).

Poor Sleep Triples The Risk Of Heart Disease

One of the ways that poor sleep may be linked to heart disease is through arterial stiffness.

One of the ways that poor sleep may be linked to heart disease is through arterial stiffness.

Poor sleep can triple the risk of heart disease, a large study finds.

Whether it was lower satisfaction with sleep, feeling sleepy during the day, lower quality sleep or less sleep overall, the worse people slept the higher their risk of heart disease.

The research included almost 7,000 adults who were asked about their sleep patterns and heart disease history.

Some also wore a device that measured their sleep activity.

Dr Soomi Lee, the study’s first author, said:

“This is one of the first studies showing that, among well-functioning adults in midlife, having more sleep health problems may increase the risk of heart disease.

The higher estimated risk in those who provided both self-report and actigraphy sleep data suggests that measuring sleep health accurately and comprehensively is important to increase the prediction of heart disease.”

Arterial stiffness

One of the ways that poor sleep may be linked to heart disease is through arterial stiffness.

Less than seven, or more than eight, hours of sleep can cause arterial stiffness leading to heart disease or stroke, a previous study has found.

Participants who had more than eight hours a night were at a 39 percent higher risk of plaque build-up inside the arteries and for those who slept less than six hours the odds increased to 54 percent.

Consequently, people who sleep more than eight hours or less than seven hours are at higher risk of heart disease or stroke.

Duration of sleep may be as important as exercise and diet for cardiovascular health.

How much sleep?

How much sleep we need is related to factors such as age.

The guidelines for adults are mostly seven to nine hours sleep a night, however, one in three American adults gets less than six hours sleep.

Studies have shown that people who sleep poorly are at greater risk of high blood pressure, heart disease, diabetes, obesity, mental health problem, and early death.

The study was published in the journal Scientific Reports (Lee et al., 2022).

The Best Sleep Position For Clearing The Brain of Waste (M)

On your side, face-up or face-down? The position which best clears metabolic waste from your brain at night.

On your side, face-up or face-down? The position which best clears metabolic waste from your brain at night.

Sleeping on your side removes waste from the brain most efficiently, a study finds.

As a result, sleeping in a lateral position may help reduce the chance of developing Alzheimer’s and other neurological diseases.

Professor Maiken Nedergaard, one of the study’s authors, said:

“It is interesting that the lateral sleep position is already the most popular in human and most animals — even in the wild — and it appears that we have adapted the lateral sleep position to most efficiently clear our brain of the metabolic waste products that built up while we are awake.

The study therefore adds further support to the concept that sleep subserves a distinct biological function of sleep and that is to ‘clean up’ the mess that accumulates while we are awake.

Many types of dementia are linked to sleep disturbances, including difficulties in falling asleep.

It is increasing acknowledged that these sleep disturbances may accelerate memory loss in Alzheimer’s disease.

Our finding brings new insight into this topic by showing it is also important what position you sleep in.”

The study of mice tested the brain’s ‘clean-up’ mechanism in three different sleeping positions:

  • On the side,
  • face-down,
  • and face-up.

Scientists monitored the filtering of cerebrospinal fluid (CSF) through the brain as it exchanged with interstitial fluid.

This pathway — called the glymphatic pathway — clears waste from the brain most efficiently at night.

Professor Helene Benveniste, another of the study’s authors, said:

“The analysis showed us consistently that glymphatic transport was most efficient in the lateral position when compared to the supine or prone positions.

Because of this finding, we propose that the body posture and sleep quality should be considered when standardizing future diagnostic imaging procedures to assess CSF-ISF transport in humans and therefore the assessment of the clearance of damaging brain proteins that may contribute to or cause brain diseases.”

The next step will be to test the finding in humans.

The research was published in the Journal of Neuroscience (Lee et al., 2015).

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