Tag: dementia

Difficulty Falling Asleep Linked to Developing Dementia

Old man
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Adding to the growing body of evidence on sleep disturbances and cognitive impairment, new research published in the American Journal of Preventive Medicine, finds significant links between three measures of sleep disturbance and the risk for developing dementia over a 10-year period. Difficulties falling asleep were linked to higher risk, but not falling asleep again after waking.

The results associate sleep-initiation insomnia (trouble falling asleep within 30 min) and sleep medication use with higher dementia risk. An additional, surprising finding was that people who reported having sleep-maintenance insomnia (trouble falling back to sleep after waking) were less likely to develop dementia over the course of the study.

“We expected sleep-initiation insomnia and sleep medication usage to increase dementia risk, but we were surprised to find sleep-maintenance insomnia decreased dementia risk,” explained lead investigator Roger Wong, PhD, MPH, MSW, an Assistant Professor in the Department of Public Health and Preventive Medicine, SUNY Upstate Medical University. “The motivation behind this research was prompted on a personal level. My father has been experiencing chronic sleep disturbances since the COVID pandemic began, and I was concerned how this would affect his cognition in the future. After reading the existing literature, I was surprised to see mixed findings on the sleep-dementia relationship, so I decided to investigate this topic.”

This research is novel because it is the first to examine how long-term sleep disturbance measures are associated with dementia risk using a nationally representative US older adult sample. Previous research has associated REM sleep behavior, sleep deprivation (less than five hours of sleep), and the use of short-acting benzodiazepines with cognitive decline. Their results for sleep-maintenance insomnia support other recent studies using smaller, separate data samples.

This study used 10 annual waves (2011–2020) of prospective data from the National Health and Aging Trends Study (NHATS), a longitudinal panel study that surveys a nationally representative sample of Medicare beneficiaries aged 65 years and older within the USA. This study included only people who were dementia-free at baseline in 2011.

While the mechanism for decreased dementia risk among those with sleep-maintenance insomnia is still unknown, the investigators theorise that greater engagement in activities that preserve or increase cognitive reserve may thereby decrease dementia risk.

Recent evidence indicates there is a higher prevalence of sleep disturbances among older adults than among other age groups. This could be attributed to a variety of factors including anxiety about the COVID pandemic or warmer nights as a consequence of climate change.

“Older adults are losing sleep over a wide variety of concerns. More research is needed to better understand its causes and manifestations and limit the long-term consequences,” added Dr Wong. “Our findings highlight the importance of considering sleep disturbance history when assessing the dementia risk profile for older adults. Future research is needed to examine other sleep disturbance measures using a national longitudinal sample, whether these sleep-dementia findings hold true for specific dementia subtypes, and how certain sociodemographic characteristics may interact with sleep disturbances to influence dementia risk.”

Source: Elsevier

Vitamin D Supplements may Ward off Dementia

Vitamin D pills
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Taking vitamin D supplements may help ward off dementia, according to a new, large-scale study published in Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring.

Canadian and UK researchers explored the relationship between vitamin D supplementation and dementia in more than 12 388 participants of the US National Alzheimer’s Coordinating Center, who had a mean age of 71 and were dementia-free when they signed up.

The team found that taking vitamin D was associated with living dementia-free for longer, and they also found 40% fewer dementia diagnoses in the group who took supplements.

Of the group, 2696 participants progressed to dementia over ten years; amongst them, 2017 (75%) had no exposure to vitamin D throughout all visits prior to dementia diagnosis, and 679 (25%) had baseline exposure.

Professor Zahinoor Ismail, of the University of Calgary and University of Exeter, who led the research, said: “We know that vitamin D has some effects in the brain that could have implications for reducing dementia, however so far, research has yielded conflicting results. Our findings give key insights into groups who might be specifically targeted for vitamin D supplementation. Overall, we found evidence to suggest that earlier supplementation might be particularly beneficial, before the onset of cognitive decline.”

While Vitamin D was effective in all groups, the team found that effects were significantly greater in females, compared to males. Similarly, effects were greater in people with normal cognition, compared to those who reported signs of mild cognitive impairment – changes to cognition which have been linked to a higher risk of dementia.

The effects of vitamin D were also significantly greater in people who did not carry the APOEe4 gene, known to present a higher risk for Alzheimer’s dementia, compared to non-carriers. The authors suggest that people who carry the APOEe4 gene absorb vitamin D better from their intestine, which might reduce the vitamin D supplementation effect. However, no blood levels were drawn to test this hypothesis.

Previous research has found that low levels of vitamin D are linked to higher dementia risk. Vitamin D is involved in the clearance of amyloid in the brain, the accumulation of which is one of the hallmarks of Alzheimer’s disease. Studies have also found that vitamin D may provide help to protect the brain against build-up of tau, another protein involved in the development of dementia.

Co-author Dr Byron Creese, at the University of Exeter, said: “Preventing dementia or even delaying its onset is vitally important given the growing numbers of people affected. The link with vitamin D in this study suggests that taking vitamin D supplements may be beneficial in preventing or delaying dementia, but we now need clinical trials to confirm whether this is really the case. The ongoing VitaMIND study at the University of Exeter is exploring this issue further by randomly assigning participants to either take vitamin D or placebo and examining changes in memory and thinking tests over time.”

Source: University of Exeter

In Older Women, Physical Activity Reduces Risk of Dementia

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Senior women were less likely to develop mild cognitive impairment or dementia if they did more daily walking and moderate-to-vigorous physical activity, according to a new study published in of Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.

The University of California San Diego-led team reported that among women aged 65 or older, each extra 31 minutes per day of moderate-to-vigorous physical activity was linked to a 21% lower risk of developing mild cognitive impairment or dementia. Risk was also reduced by 33% with each extra 1865 daily steps.

“Given that the onset of dementia begins 20 years or more before symptoms show, the early intervention for delaying or preventing cognitive decline and dementia among older adults is essential,” said senior author Andrea LaCroix, PhD, MPH, UC San Diego professor.

Dementias are a debilitating neurological condition that can cause loss of memory, the ability to think, problem solve or reason. Mild cognitive impairment is an early stage of memory loss or thinking problems that is not as severe as dementias.

More women live with and are at higher risk of developing dementia than men.

“Physical activity has been identified as one of the three most promising ways to reduce risk of dementia and Alzheimer’s disease. Prevention is important because once dementia is diagnosed, it is very difficult to slow or reverse. There is no cure,” said LaCroix.

However, because few large studies have examined device measures of movement and sitting in relation to mild cognitive impairment and dementia, much of the published research on the associations of physical activity and sedentary behavior with cognitive decline and dementia is based on self-reported measures, said first author, Steven Nguyen, Ph.D., M.P.H., postdoctoral scholar at the Herbert Wertheim School of Public Health.

For this study, the researchers sampled data from 1,277 women as part of two Women’s Health Initiative (WHI) ancillary studies – the WHI Memory Study (WHIMS) and the Objective Physical Activity and Cardiovascular Health (OPACH) study. The women wore research-grade accelerometers and went about their daily activities for up to seven days to obtain accurate measures of physical activity and sitting.

The activity trackers showed the women averaged 3,216 steps, 276 minutes in light physical activities, 45.5 minutes of moderate-to-vigorous physical activity and 10.5 hours of sitting per day. Examples of light physical activity could include housework, gardening or walking. Moderate-to-vigorous physical activity could include brisk walking.

The study findings also showed that higher amounts of sitting and prolonged sitting were not associated with higher risk of mild cognitive impairment or dementia.

Together, this information has clinical and public health importance as there is little published information on the amount and intensity of physical activity needed for a lower dementia risk, said Nguyen.

“Older adults can be encouraged to increase movement of at least moderate intensity and take more steps each day for a lower risk of mild cognitive impairment and dementia,” said Nguyen.

“The findings for steps per day are particularly noteworthy because steps are recorded by a variety of wearable devices increasingly worn by individuals and could be readily adopted.”

The authors said further research is needed among large diverse populations that include men.

Source: University of California – San Diego

A Severe Form of Dementia may in Fact be Caused by a Cerebrospinal Fluid Leak

MRI images of the brain
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A new study suggests that some patients diagnosed with behavioural-variant frontotemporal dementia (bvFTD) – a presently incurable, mentally debilitating condition – may instead have a cerebrospinal fluid leak, which is detectable on MRI scans and often treatable. The researchers say these findings, published in the peer-reviewed journal Alzheimer’s & Dementia: Translational Research and Clinical Interventionscould lead to a cure.

“Many of these patients experience cognitive, behavioural and personality changes so severe that they are arrested or placed in nursing homes,” said Wouter Schievink, MD, professor of Neurosurgery at Cedars-Sinai. “If they have behavioural-variant frontotemporal dementia with an unknown cause, then no treatment is available. But our study shows that patients with cerebrospinal fluid leaks can be cured if we can find the source of the leak.”

When cerebrospinal fluid (CSF) leaks into the body, the brain can sag, causing dementia symptoms. Schievink said many patients with brain sagging, detectable in MRI, go undiagnosed, and he advises clinicians to take a second look at patients with telltale symptoms.

“A knowledgeable radiologist, neurosurgeon or neurologist should check the patient’s MRI again to make sure there is no evidence for brain sagging,” Schievink said.

Clinicians can also ask about a history of severe headaches that improve when the patient lies down, significant sleepiness even after adequate night-time sleep, and whether the patient has ever been diagnosed with a Chiari brain malformation, a condition in which brain tissue extends into the spinal canal. Brain sagging, Schievink said, is often mistaken for a Chiari malformation.

Even when brain sagging is detected, the source of a CSF leak can be difficult to locate. When the fluid leaks through a tear or cyst in the surrounding membrane, it is visible on CT myelogram imaging with the aid of contrast medium.

Schievink and his team recently discovered an additional cause of CSF leak: the CSF-venous fistula. In these cases, the fluid leaks into a vein, making it difficult to see on a routine CT myelogram. To detect these leaks, technicians must use a specialized CT scan and observe the contrast medium in motion as it flows through the cerebrospinal fluid.

In this study, investigators used this imaging technique on 21 patients with brain sagging and symptoms of bvFTD, and they discovered CSF-venous fistulas in nine of those patients. All nine patients had their fistulas surgically closed, and their brain sagging and accompanying symptoms were completely reversed.

“This is a rapidly evolving field of study, and advances in imaging technology have greatly improved our ability to detect sources of CSF leak, especially CSF-venous fistula,” said Keith L. Black, MD, chair of the department of Neurosurgery at Cedars-Sinai. “This specialised imaging is not widely available, and this study suggests the need for further research to improve detection and cure rates for patients.”

The remaining 12 study participants, whose leaks could not be identified, were treated with nontargeted therapies designed to relieve brain sagging, such as implantable systems for infusing the patient with CSF. However, only three of these patients experienced relief from their symptoms.

“Great efforts need to be made to improve the detection rate of CSF leak in these patients,” Schievink said. “We have developed nontargeted treatments for patients where no leak can be detected, but as our study shows, these treatments are much less effective than targeted, surgical correction of the leak.”

Source: Cedars-Sinai Medical Center

Hearing Loss Linked to Dementia Risk

A nationally representative study published in JAMA found that older adults with greater severity of hearing loss were more likely to have dementia, but the likelihood of dementia was lower among hearing aid users compared to non-users.

The findings are consistent with prior studies showing that hearing loss might be a contributing factor to dementia risk over time, and that treating hearing loss may lower dementia risk.

“This study refines what we’ve observed about the link between hearing loss and dementia, and builds support for public health action to improve hearing care access,” says lead author Alison Huang, PhD, MPH, a senior research associate in the Bloomberg School’s Department of Epidemiology and at the Cochlear Center for Hearing and Public Health, also at the Bloomberg School.

Hearing loss is a critical public health issue affecting two-thirds of Americans over 70. The growing understanding that hearing loss might be linked to the risk of dementia, which impacts millions, and other adverse outcomes has called attention to implementing possible strategies to treat hearing loss.

For the new study, Huang and colleagues analysed a nationally representative dataset from the National Health and Aging Trends Study (NHATS). Funded by the National Institute on Aging, the NHATS has been ongoing since 2011, and uses a nationwide sample of Medicare beneficiaries over age 65, with a focus on the 90-and-over group as well as Black individuals.

The analysis covered 2413 individuals, about half of whom were over 80 and showed a clear association between severity of hearing loss and dementia. Prevalence of dementia among the participants with moderate/severe hearing loss was 61% higher than prevalence among participants who had normal hearing. Hearing aid use was associated with a 32% lower prevalence of dementia in the 853 participants who had moderate/severe hearing loss.

The authors note that many past studies were limited in that they relied on in-clinic data collection, leaving out vulnerable populations that did not have the means or capacity to get to a clinic. For their study, the researchers collected data from participants through in-home testing and interviews.

How hearing loss is linked to dementia isn’t yet clear, and studies point to several possible mechanisms. Huang’s research adds to a body of work by the Cochlear Center for Hearing and Public Health examining the relationship between hearing loss and dementia.

Source: Johns Hopkins Bloomberg School of Public Health

Best Evidence Yet That Lowering Blood Pressure Cuts Dementia Risk

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A global study of over 28 000 people has provided the strongest evidence to date that lowering blood pressure in later life can cut the risk of dementia. The study, which included five randomised controlled trials, was published in the European Heart Journal, and constitutes the highest grade of evidence for this preventative association.

Dr Ruth Peters, Program Lead for Dementia in The George Institute’s Global Brain Health Initiative, said that with no significant dementia treatment breakthroughs being made, reducing the risk of developing the disease would be a welcome step forward.

“Given population ageing and the substantial costs of caring for people with dementia, even a small reduction could have considerable global impact,” she said.

“Our study suggests that using readily available treatments to lower blood pressure is currently one of our ‘best bets’ to tackle this insidious disease.”

Dementia is fast becoming a global epidemic, currently affecting an estimated 50 million people worldwide. This number is projected to triple by 2050 mainly from ageing populations.

Current estimates put the cost at US$20–$40 000 per person with the condition each year.

Dr Peters explained that while many trials have looked at the health benefits of lowering blood pressure, few included dementia outcomes and even fewer were placebo-controlled.

“Most trials were stopped early because of the significant impact of blood pressure lowering on cardiovascular events, which tend to occur earlier than signs of dementia,” she said.

To examine the relationship between blood pressure and dementia more closely, researchers analysed five double-blind placebo-controlled randomised trials that used different blood pressure lowering treatments and followed patients until the development of dementia. A total of 28 008 individuals with an average age of 69 and a history of hypertension from 20 countries were included. Across these studies, the mid-range of follow up was just over four years.

“We found there was a significant effect of treatment in lowering the odds of dementia associated with a sustained reduction in blood pressure in this older population,” said Dr Peters.

“Our results imply a broadly linear relationship between blood pressure reduction and lower risk of dementia, regardless of which type of treatment was used.”

Researchers hope the results will help in designing public health measures to slow the advance of dementia as well as informing treatment, where there may be hesitancy in how far to lower blood pressure in older age.

“Our study provides the highest grade of available evidence to show that blood pressure lowering treatment over several years reduces the risk of dementia, and we did not see any evidence of harm,” said Dr Peters.

“But what we still don’t know is whether additional blood pressure lowering in people who already have it well-controlled or starting treatment earlier in life would reduce the long-term risk of dementia,” she added.

Source: George Institute for Global Health

Do Women Have the Edge in Remembering Words?

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Women are popularly believed at being better at finding and remembering words than men, but are the popular science textbooks which proclaim this actually correct? If so, this has relevance for tests such as measures of dementia. Researchers investigated this supposed difference, publishing their findings in Perspectives on Psychological Science.

Marco Hirnstein, professor at The University of Bergen, Norway, is unequivocal about the results. “Women are better. The female advantage is consistent across time and life span, but it is also relatively small.”

Prof Hirnstein is interested in how biological, psychological, and social factors contribute to sex/gender differences in cognitive abilities and what the underlying brain mechanisms are.

“So far, the focus has mostly been on abilities, in which men excel. However, in recent years the focus has shifted more towards women,” said Prof Hirnstein.

Textbooks and popular science books take it for granted that women are better at finding words. For example, when naming words that begin with the letter “F,” or words that belong to a certain category like animals or fruits. It has also been considered “fact” that women are better at remembering words.

Yet, the actual findings are much more inconsistent than textbooks imply: Some studies find a female advantage, some find a male advantage, some do not find any advantage.

“Most intellectual skills show no or negligible differences in average performance between men and women. However, women excel in some tasks, while men excel in others on average.”

Prof Hirnstein and his colleagues point out how their findings can be useful in diagnosis and in healthcare. The results help to clarify whether the female advantage is real but also have relevance for for interpreting the results of diagnostic assessments.

For example, to diagnose dementia, knowing that women are generally better in those tasks is critical to not under-diagnose women, due to their better average, baseline performance and not over-diagnose men. Currently, many but not all assessments take sex/gender into account.

The researchers conducted a meta-analysis of the available literatures, encompassing more than 500 measures from more than 350,000 participants. The researchers found that women are indeed better. The advantage is small but consistent across the last 50 years and across an individual’s lifespan.

Moreover, they found that the female advantage depends on the sex/gender of the leading scientist: Female scientists report a larger female advantage, male scientists report a smaller female advantage.

Source: University of Bergen

A Mediterranean Diet Doesn’t Keep Dementia at Bay

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It has been suggested in a number of studies that eating a healthy diet may reduce a person’s risk of dementia. A new study published in the journal Neurology has found, however, that both the conventionally recommended diet and the Mediterranean diet are not linked to a reduced risk of dementia.

The Mediterranean diet features a high intake of vegetables, legumes, fruits, fish and healthy fats such as olive oil, and a low intake of dairy products, meats and saturated fatty acids. “Previous studies on the effects of diet on dementia risk have had mixed results,” said study author Isabelle Glans, MD, of Lund University. “While our study does not rule out a possible association between diet and dementia, we did not find a link in our study, which had a long follow-up period, included younger participants than some other studies and did not require people to remember what foods they had eaten regularly years before.”

For the study, researchers identified 28 000 people from Sweden. Participants had an average age of 58 and did not have dementia at the start of the study. They were followed over a 20-year period. During the study, participants filled out a seven-day food diary, a detailed food frequency questionnaire and completed an interview. By the end of the study, 1943 people, or 6.9%, were diagnosed with dementia, including Alzheimer’s disease and vascular dementia.

Researchers examined how closely participants’ diets aligned with conventional dietary recommendations and the Mediterranean diet. After adjusting for age, gender, and education, researchers did not find a link between following either a conventional diet or the Mediterranean diet and a reduced risk of dementia. Dr Glans noted that further research is needed to confirm the findings.

Nils Peters, MD, of the University of Basel in Switzerland, who wrote an editorial accompanying the study, said, “Diet on its own may not have a strong enough effect on memory and thinking, but is likely one factor among others that influence the course of cognitive function. Dietary strategies will still potentially be needed along with other measures to control risk factors.” A limitation of the study was the risk of participants misreporting their own dietary and lifestyle habits.

Source: American Academy of Neurology

Link Found Between Dementia Indicators and Metabolism

MRI images of the brain
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A world-first study published in the journal Diabetes, Obesity and Metabolism, has uncovered an association between metabolism and dementia-related brain measures, providing valuable insights about the disease.

Analysing UK Biobank data from 26 239 people, University of South Australia researchers found that those with obesity related to liver stress, or to inflammation and kidney stress, had the most adverse brain findings.

The study measured associations of six diverse metabolic profiles and 39 cardiometabolic markers, using MRI brain scan measures of brain volume, brain lesions, and iron accumulation, to identify early risk factors for dementia.

Participants with metabolic profiles associated with obesity were more likely to have adverse MRI profiles showing lower hippocampal and grey matter volumes, greater burden of brain lesions, and higher accumulation of iron.

UniSA researcher, Dr Amanda Lumsden, says the research adds a new layer of understanding to brain health.

“Dementia is a debilitating disease that affects more than 55 million people worldwide,” Dr Lumsden said.

“Understanding metabolic factors and profiles associated with dementia-related brain changes can help identify early risk factors for dementia.

“In this research, we found that adverse neuroimaging patterns were more prevalent among people who had metabolic types related to obesity.

“These people also had the highest Basal Metabolic Rate (BMR) -how much energy your body requires when resting in order to support its basic functions — but curiously, BMR seemed to contribute to adverse brain markers over and above the effects of obesity.”

Senior investigator Professor Elina Hyppönen said that the finding presents a new avenue for understanding brain health.

“This study indicates that metabolic profiles are associated with aspects of brain health. We also found associations with many individual biomarkers which may provide clues into the processes leading to dementia,” said Prof Hyppönen.

“The human body is complex, and more work is now needed to find out exactly why and how these associations arise.”

Source: University of South Australia

7 Lifestyle Habits may Reduce Dementia Risk in Diabetes

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A combination of seven healthy lifestyle habits including sleeping seven to nine hours daily, regular exercise and frequent social contact was associated with a lower risk of dementia in people with type 2 diabetes, according to a study published online in the journal Neurology.

“Type 2 diabetes is a worldwide epidemic that affects one in 10 adults, and having diabetes is known to increase a person’s risk of developing dementia,” said study author Yingli Lu, MD, PhD, of Shanghai Jiao Tong University School of Medicine in China. “We investigated whether a broad combination of healthy lifestyle habits could offset that dementia risk and found that people with diabetes who incorporated seven healthy lifestyle habits into their lives had a lower risk of dementia than people with diabetes who did not lead healthy lives.”

For the study, researchers looked at a health care database in the United Kingdom and identified 167 946 people 60 or older with and without diabetes who did not have dementia at the start of the study. Participants completed health questionnaires, provided physical measurements and gave blood samples. For each participant, researchers calculated a healthy lifestyle score of 0 to 7, with one point for each of 7 healthy habits. Habits included no current smoking, moderate alcohol consumption of up to one drink a day for women and up to two a day for men, regular weekly physical activity of at least 2.5 hours of moderate exercise or 75 minutes of vigorous exercise, and 7 to nine hours of sleep daily.

Another factor was a healthy diet including more fruits, vegetables, whole grains and fish and fewer refined grains, processed and unprocessed meats. The final habits were being less sedentary, which was defined as watching television less than four hours a day, and frequent social contact, which was defined as living with others, gathering with friends or family at least once a month and participating in social activities at least once a week or more often. Researchers followed participants for an average of 12 years. During that time, 4,351 people developed dementia. A total of 4% of the people followed only zero to two of the healthy habits, 11% followed three, 22% followed four, 30% followed five, 24% followed six and 9% followed all seven. People with diabetes who followed two or fewer of the seven healthy habits were four times more likely to develop dementia than people without diabetes who followed all seven healthy habits. People with diabetes who followed all of the habits were 74% more likely to develop dementia than those without diabetes who followed all the habits. For people with diabetes who followed all the habits, there were 21 cases of dementia for 7474 person-years, or 0.28%.

For people with diabetes who followed only two or fewer habits, there were 72 cases of dementia for 10 380 person years or 0.69%. After adjusting for factors like age, education and ethnicity, people who followed all the habits had a 54% lower risk of dementia than those who followed two or fewer. Each additional healthy habit people followed was associated with an 11% decreased risk of dementia. The association between healthy lifestyle score and dementia risk was not affected by medications people took or how well they controlled their blood sugar.

“Our research shows that for people with type 2 diabetes, the risk of dementia may be greatly reduced by living a healthier lifestyle,” Dr Lu said. “Doctors and other medical professionals who treat people with diabetes should consider recommending lifestyle changes to their patients. Such changes may not only improve overall health, but also contribute to prevention or delayed onset of dementia in people with diabetes.” A limitation of the study was that people reported on their lifestyle habits and may not have remembered all details accurately. Lifestyle changes over time were also not captured.

Source: American Academy of Neurology