- High blood pressure and dementia
- What is high blood pressure?
- What does the research say about high blood pressure and dementia?
- How does high blood pressure affect brain function?
- How can I control my blood pressure?
- Rare blood type linked to dementia risk
- Memory loss more common in people with blood type AB
- Why Do Certain Blood Types Have a Higher Risk of Dementia?
- Gray Matter Brain Volume in the Cerebellum May Have Neuroprotective Benefits
- The approximate distribution of blood types in the U.S. population:
- Conclusion: “Microzones” Within the Cerebellum Have Specific Functions
- Your Blood Type Could Affect Your Memory
- Which Blood Type Increases Your Risk of Dementia?
- Can Your Blood Type Affect Your Memory?
- People with blood type AB more at risk of cognitive decline and dementia
- Blood links to other health problems
- Can your blood type protect you from getting dementia?
- ABO blood group and neurodegenerative disorders: more than a casual association
High blood pressure and dementia
Long-term research studies have demonstrated that high blood pressure in mid-life is a key factor that can increase your risk of developing dementia in later life, particularly vascular dementia. These findings highlight that a lifelong approach to good health as the best way to lower your risk of dementia.
What is high blood pressure?
Blood pressure measures the force applied to your arteries (the major blood vessels that carry blood to our essential organs) as blood is circulated around the body by the heart.
It is measured by your GP using a blood pressure cuff or with a 'self-service' machine, which is available at some GP practices. Your blood pressure is reported as two numbers. The first represents the systolic pressure, a measure of the pressure on your arteries per beat of the heart.
The second is the diastolic pressure, a measure of the remaining pressure when the heart rests between beats. A normal blood pressure reading is around 120/80 mmHg.
High blood pressure, also known as hypertension, is diagnosed when your blood pressure is consistently above 140/90 mmHg.
It is a serious condition that is a major cause of heart attack and stroke worldwide. By 2025, it is estimated that 1.56 billion people globally will be diagnosed with high blood pressure.
The known risk factors for high blood pressure include lack of exercise, being overweight or obese, an unhealthy diet that is high in salty food, alcohol consumption that exceeds the recommended maximum, drinking a lot of caffeine, smoking, a family history of high blood pressure, use of steroid medication, kidney disease and being of African or Caribbean descent.
What does the research say about high blood pressure and dementia?
According to the World Alzheimer Report 2014, multiple studies following large groups of people for 15-40 years have demonstrated that individuals who had high blood pressure in mid-life (usually characterised as people who are around 40-64 years of age) were more ly to develop vascular dementia in later life.
Vascular dementia is the second most common form of dementia after Alzheimer's disease. It is caused by reduced blood flow to the brain, which starves brain cells of the oxygen and nutrients they need to function correctly. The association between high blood pressure and Alzheimer's disease is currently unclear.
However, despite this apparent link between vascular dementia and high blood pressure, the results from randomised controlled trials into whether lowering blood pressure can prevent dementia have so far been inconclusive.
This research demonstrates the importance of conducting studies that follow individuals over a long period of time (called longitudinal studies), to connect a person's lifestyle choices and health profile throughout their life to the risk of disease development in later life.
How does high blood pressure affect brain function?
There are several mechanisms by which high blood pressure affects the brain. High blood pressure causes a great deal of strain on the arteries over time, and this in turn causes the wall of the arteries to become thicker and stiffer as well as narrower. This is called arteriosclerosis.
Fats found in the blood also contribute to the development of the narrowing of the arteries. This narrowing of the arteries can happen in the brain, causing a lack of essential nutrients and oxygen, which can damage brain cells and prevent them from functioning correctly.
High blood pressure is also the strongest risk factor for stroke.
The most common cause of stroke is the blockage of the arteries in the brain (ischaemic stroke) and half of these are caused by hardening of the arteries. Another important cause of stroke is the bursting of an artery in the brain, causing what is known as a haemorrhagic stroke, also called bleeding in the brain.
Both type of strokes cause brain cell death that can lead to the development of stroke-related or post-stroke vascular dementia.
Narrowing of the blood vessels especially deep inside the brain does not always cause an overt stroke. These very small deep blood vessels can be blocked or have small bleeds (microbleeds).
The person may not feel anything wrong at the time, but the gradual accumulation of these changes over the years becomes visible on the brain scan and is called small vessel disease.
This is a major contributing factor in the development of subcortical vascular dementia.
How can I control my blood pressure?
It is important to first get an accurate idea of what your blood pressure is. In England, it is estimated that 30% of the population have high blood pressure but, due to the lack of symptoms, it may go undiagnosed until a severe cardiac event (for example a heart attack or angina) occurs.
Finding out your blood pressure can be easily done through a visit to your GP or by visiting a blood pressure booth in your local pharmacy and the NHS recommends that it should be checked every five years.
There are things you can do to lower your blood pressure if it is too high.
One way is through a series of lifestyle changes that include losing weight, exercising regularly, maintaining a healthy diet that is low in salt, reducing caffeine and alcohol consumption, and quitting smoking.
Alternatively, high blood pressure can be controlled through the use of blood pressure medication, which is prescribed by your doctor. These blood pressure lowering drugs have been shown to be safe and effective.
However it is important to note that they have not been proven or recommended to directly prevent vascular dementia. There is a great deal of research into finding potential therapies that may be able to slow down or prevent development of vascular dementia.
If you have high blood pressure, it is important to talk to your doctor before attempting any lifestyle changes or trying new medication so they can provide you with personalised recommendations and monitor your progress.
A key take away message from these longitudinal research studies is that a life-long approach to health is important.
Keeping blood pressure levels normal is only one factor, along with exercise, diet, smoking, and alcohol consumption that is important to consider when attempting minimising your risk of developing dementia.
High blood pressure does not give you any symptoms initially so it is important to be proactive and find out what your blood pressure is.
Rare blood type linked to dementia risk
Your blood type may play a small role in your risk for dementia, a new study finds.
People with blood type AB, which includes about 4 percent of the population, appear to have an increased risk for memory problems as they age. Over about three years, individuals with blood type AB were almost twice as ly to show memory problems as those with type O blood, the most common blood group, the study found.
But experts cautioned that those with AB blood shouldn't panic because other circumstances play a bigger part in their risk for mental impairment.
“If you were to do the same study and look at smoking, lack of exercise, obesity and other lifestyle factors, the risk of dementia is much, much higher,” said Dr.
Terence Quinn, a clinical lecturer in stroke and geriatric medicine at the University of Glasgow in Scotland.
“People who are worried about dementia, whether they have that blood group or not, should look at making those lifestyle changes.”
Alzheimer's disease: 7 things that raise your risk 8 photos
In the study, researchers gave more than 30,000 people, aged 45 and older, a series of memory and thinking skills tests and then tested them again a little more than three years later.
From this group, 495 participants scored low enough to qualify as having some memory or thinking impairment, and their blood types were compared to those of 587 participants with normal cognitive (mental) scores.
After making adjustments for differences in the participants' age, race, sex and geographical region, those who had AB blood types were 82 percent more ly to have impaired thinking skills than those with type O blood, according to the study.
Yet these findings, published online Sept. 10 in the journal Neurology, aren't necessarily surprising considering other recent research, said the study's senior researcher, Dr.
Mary Cushman, a professor of hematology at the University of Vermont College of Medicine. It's already known that having blood type AB can affect blood clotting characteristics and risk of blood vessel-related conditions, she said.
In addition, her research group found earlier this year that the AB blood type was linked to a higher risk of stroke.
About half of the association between stroke and AB blood type in the previous study was related to higher levels of clotting factor VIII, a blood protein that helps blood clot to stop bleeding.
Factor VIII is the protein that is deficient in individuals with hemophilia. Too little factor VIII, and a person's blood doesn't clot properly.
Too much, and the body forms clots too easily, potentially leading to heart attacks, stroke or large blood clots that clog veins.
But in this study, only about 20 percent of the association between memory problems and AB blood type could be explained by higher levels of factor VIII, suggesting other reasons for the link, Cushman said.
Though it's not clear what those reasons are, it may relate to the link between AB blood type and vascular problems, considering that stroke and dementia share several risk factors, she said. Those with memory and thinking impairment in the study were also more ly to smoke and to have high blood pressure, diabetes, heart disease or high cholesterol.
“People who have AB blood type should not be overly worried about these findings since the association we saw was relatively small and requires other research for confirmation,” Cushman said. An association does not prove cause-and-effect.
She said it's more important that all individuals aim for a healthy lifestyle, regardless of blood type. Healthy lifestyle choices she recommended included not smoking, exercising regularly, maintaining a healthy diet and keeping up with preventive care, such as controlling blood pressure and blood sugar.
“It is also important to exercise your brain by staying 'cognitively active' with things reading and playing games cards or puzzles,” Cushman said.
Quinn, who wasn't involved in the research, said the study provides some insight into the underlying cause of dementia. “Along with other work, this study implies that blood is a predictor of dementia, and that's probably related to possible changes in blood, such as silent strokes or silent blood clots, that may, over time, cause memory problems.”
He also emphasized the importance of healthy behaviors in reducing your risk of dementia.
“Although these studies are interesting and give us knowledge, the way to prevent dementia is not through drugs that affect blood,” Quinn said. “It's through environmental, lifestyle factors.”
Memory loss more common in people with blood type AB
Several research studies have pinpointed lifestyle changes individuals can make to prevent memory loss, such as keeping stress and blood sugars low, and not smoking. But a new study pinpoints a potential risk factor for memory loss that we can do nothing about: our blood type.
Share on PinterestThe new study suggests people with blood type AB are 82% more ly to develop thinking and memory problems that can lead to dementia.
The study was supported by the National Institutes of Health and the US Department of Health and Human Services, among other organizations, and is published in the journal Neurology.
The type of blood we have depends on whether or not there are certain proteins – called antigens – in our red blood cells, and this blood type is passed down from our parents.
There are four main blood types: type A, type B, type AB and type O. Additionally, if a substance called Rh factor appears on the surface of the red blood cells, a person is considered to be Rh+ (positive).
Type O+ is the most common blood type, while AB- is the least common. But not all ethnic groups have the same proportion of blood types. For example, Hispanics have a high number of O blood types, while Asians have a high number of B blood types.
According to the authors of this latest study, led by Dr. Mary Cushman of the University of Vermont College of Medicine in Burlington, the blood type AB is only found in about 4% of the US population, yet people with this blood type were 82% more ly than other types to develop the thinking and memory problems that can lead to dementia.
They note that previous studies have shown that people with blood type O have a lower risk of heart disease and stroke, which are factors that can increase risks for memory loss and dementia.
And Medical News Today recently reported on a study that suggested men with blood type O have lower recurrence of prostate cancer.
To conduct their study, the researchers used data from a larger one called the REGARDS Study, which stands for the REasons for Geographic And Racial Differences in Stroke. This bit of research followed 30,000 people for around 3.4 years.
Of those involved in the study who did not have memory or thinking problems at the start, the researchers pinpointed 495 participants who developed thinking and memory problems or cognitive impairment during the course of the study. These participants were then compared with 587 people who did not have any cognitive difficulties.
The results show that those with blood type AB made up 6% of the group that developed cognitive impairment, compared with only 4% found in the population.
Commenting on their study, Dr. Cushman says:
“Our study looks at blood type and risk of cognitive impairment, but several studies have shown that factors such as high blood pressure, high cholesterol and diabetes increase the risk of cognitive impairment and dementia.
Blood type is also related to other vascular conditions, stroke, so the findings highlight the connections between vascular issues and brain health.”
The team also looked at blood levels of a protein that helps blood clot, called factor VIII, high levels of which have been linked to a higher risk of cognitive impairment and dementia.
Those in the study with higher levels of this protein were 24% more ly to develop thinking and memory problems during the study than those with lower levels. Additionally, participants with blood type AB had a higher level of factor VIII than people from all other blood types.
Though their findings are intriguing, Dr. Cushman cautions that “more research is needed to confirm these results.”
In January of this year, MNT reported on a study that analyzed the popular blood type diet – a lifestyle plan that recommends eating and exercising in certain ways, depending on blood type.
“The way an individual responds to any one of these diets has absolutely nothing to do with their blood type and has everything to do with their ability to stick to a sensible […] diet,” said senior author Dr. Ahmed El-Sohemy.
Why Do Certain Blood Types Have a Higher Risk of Dementia?
Source: Wikimedia/Creative Commons
Neuroscientists at the University of Sheffield have discovered that your blood type may impact gray-matter volume in brain regions linked to dementia and Alzheimer’s disease. Gray matter consists of the bulk of neurons in specific brain regions, while white matter creates communication lines between your various brain regions.
The June 2015 study, “‘O’ Blood Type is Associated with Larger Grey-Matter Volumes in the Cerebellum,” was published in Brain Research Bulletin.
For this study, Matteo De Marco and Annalena Venneri calculated the volume of gray matter in various regions of the brain and correlated these statistics with blood types and risk of dementia.
The researchers found that people with the 'O' blood type have more gray matter in the cerebellum (Latin for “Little Brain”), which may protect against neurodegenerative diseases such as Alzheimer's.
Traditionally, neuroscientists have viewed the cerebellum as the seat of muscular coordination, balance, and bodily proprioception. However, new findings indicate the cerebellum is also tied to cognitive function and may fine-tune our thinking and creative processes, just as it fine-tunes our muscle movements.
The fronto-cerebellar network connects the cerebellum to the cerebral cortex and allows for the coordination, precision, and timing of both muscle movements and thought processes. Ideally, the cerebellum allows us to move and think more efficiently.
Gray Matter Brain Volume in the Cerebellum May Have Neuroprotective Benefits
Cerebellum in red.
Source: Wikimedia Commons / Life Sciences Databases
The study found that individuals with an 'O' blood type tend to have more gray matter in the posterior portion of the cerebellum. More specifically, the ‘O’ adults had larger gray-matter volumes in two symmetrical clusters within the posterior ventral portion of the cerebellum.
Interestingly, when the researchers compared people with ‘O’ type blood to those with 'A', 'B' or 'AB' blood types they also found smaller gray matter volumes in temporal and limbic regions of the brain, including the left hippocampus.
In 2014, researchers from Harvard Medical School reported that people over age 45 with type 'AB' blood were 82% more ly to have impaired thinking skills than those with type 'O' blood.
The approximate distribution of blood types in the U.S. population:
- O-positive: 38 percent.
- O-negative: 7 percent.
- A-positive: 34 percent.
- A-negative: 6 percent.
- B-positive: 9 percent.
- B-negative: 2 percent.
- AB-positive: 3 percent.
- AB-negative: 1 percent.
The researchers hypothesize that the difference between blood types might be caused by the effects of 'O' blood type alleles on the brain.
In a press release, De Marco said,
The findings seem to indicate that people who have an 'O' blood type are more protected against the diseases in which volumetric reduction is seen in temporal and mediotemporal regions of the brain with Alzheimer's disease for instance. However additional tests and further research are required as other biological mechanisms might be involved.
De Marco's scientific research focuses on non-pharmacological treatments that can optimize healthy aging and reduce the risks of dementia and Alzheimer’s disease. His research also aims to identify the impact of physical exercise on various neurocognitive variables.
If you don't have 'O' blood, exercise may be a non-pharmacological treatment for increasing brain volume and optimizing cognitive function throughout your lifespan.
One of the prime benefits of physical activity is that exercise stimulates the production of Irisin and BDNF (Brain-derived neurotrophic factor) which triggers the growth of new neurons (neurogenesis) throughout the brain, regardless of your blood type.
Although the current study by De Marco and Venneri doesn't investigate the link between physical activity and dementia, other studies have found a universal correlation between aerobic fitness, BDNF, and increased gray-matter volumes.
Conclusion: “Microzones” Within the Cerebellum Have Specific Functions
Specific regions of the cerebellum play specific roles in cerebral processes.
Source: Wikimedia/Creative Commons
Within the cerebellum, neuroscientists continue to identify how specific cerebellar regions play a role in specific cerebral functions. The recent study from the University of Sheffield has identified clusters of gray matter within the cerebellum that may be linked to dementia and Alzheimer's disease.
Recently, researchers at Stanford University linked the cerebellum to creativity and the creative process. The new findings from the University of Sheffield reveal cerebellar gray-matter volume as a prime candidate for further investigation of ABO function as linked to neuroprotection or degeneration of cognitive functions.
If you'd to read more on this topic, check out my Psychology Today blog posts:
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© Christopher Bergland 2015. All rights reserved.
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Your Blood Type Could Affect Your Memory
Individuals with a rare blood type may have an increased risk of developing memory problems later in life, new research has found. According to the study, which has been published in Neurology, people with AB blood were almost twice as ly to develop cognitive impairment as individuals with other blood types.
Scientists have previously identified associations between blood type and vascular health. For example, some studies found that individuals with blood type O had a lower risk of developing heart disease and stroke, both of which can increase the risk of memory loss and dementia later in life.
Taking this one step further, researchers headed by Dr. Mary Cushman of the University of Vermont College of Medicine set out to examine the relationship between blood type and the incidence of cognitive impairment.
For the study, the team analyzed data from more than 30,000 black and white adults living in the US that had previously been enrolled in a larger study called REGARDS (Reasons for Geographical and Racial Differences in Stroke).
The researchers identified 495 individuals that developed cognitive impairment during the three and a half year study. They then compared these individuals with a similar group of 587 people who had no memory problems.
They found that 6% of the individuals who developed cognitive impairment had the rare blood type AB, which is higher than the 4% found in the total US population.
After adjusting for age, race, region and sex, those with AB were 82% more ly to experience problems with memory, language and attention with age when compared with other blood types.
While these are often indicative of the onset of dementia, the study did not look at the risks of developing dementia.
Alongside investigating blood type, the researchers also examined the levels of a clotting protein called factor VIII. They found that those with higher levels of factor VIII in their blood also had an increased risk of developing cognitive impairment. Furthermore, average levels of this factor were higher in those with blood type AB when compared with O.
These findings are not necessarily surprising given that previous research has demonstrated that individuals with blood type AB sometimes have altered blood clotting characteristics.
Moreover, Cushman’s group previously found that blood type AB was associated with a higher risk of stroke.
High levels of factor VIII increases the lihood of blood clots forming and therefore may also increase the risk of developing heart attacks or stroke.
“Our study looks at blood type and risk of cognitive impairment, but several studies have shown that factors such as high blood pressure, high cholesterol and diabetes increase the risk of cognitive impairment and dementia,” Cushman said in a news release. “Blood type is also related to other vascular conditions stroke, so the findings highlight the connections between vascular issues and brain health.”
While this research is interesting, an association cannot prove that AB blood type is causing the increased risk of cognitive impairment. Further studies are therefore warranted.
[Via American Academy of Neurology, Neurology, CBS News and BBC News]
Read this: Ancient River Dolphin Relative Discovered In Peru Desert
Which Blood Type Increases Your Risk of Dementia?
Lutz Pape/Getty Images
Science has identified several risk factors for dementia including smoking, high blood pressure, genetics, diabetes and more. But one study suggests that your blood type may also influence your risk for cognitive problems, affecting memory, word-finding, personality, and more.
A team of researchers studied more than 30,000 people over the course of a 3 1/2 year period. During the study, the participants' cognitive functioning was tested to determine if any decline was present. Researchers used tests that measured verbal fluency, immediate memory, orientation, and ability to learn a 10-word list.
At the end of the study period, significant cognitive decline had developed in 495 people. Of this group, researchers found that one particular blood type demonstrated a higher risk for cognitive decline: the type of blood known as AB. Additionally, higher levels of factor VIII- a protein that facilitates clotting of blood- were also correlated with a greater risk of cognitive problems.
AB blood is quite rare. According to the American Red Cross, about 4 percent of Caucasians, 4.3 percent of African-Americans, 2.2 percent of Hispanic Americans and 7.1 percent of Asian Americans have AB blood.
One theorized reason by the study's authors why blood type AB is correlated with a higher risk of cognitive impairment is that this blood type is also more highly connected to cardiovascular problems, and research has already demonstrated a tie between heart problems and cognitive decline. Additionally, risk of cardiovascular disease is increased by some of the same risk factors that are tied to a higher risk of dementia, including obesity and diabetes.
First, remember that this is only a single study, and it needs to be replicated to determine if the same results occur in other research.
Also, although this study does show a correlation (note that it does not prove that one causes the other) between blood type and risk of cognitive decline, research has demonstrated that there are many other factors that have shown to be associated with a reduced risk of dementia. In other words, there are many things that you CAN control that reduce your dementia risk. Diet, physical exercise, and mental activity all have repeatedly been correlated with reduced risk of dementia.
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- Alexander, Kristine S., Zakai, Neil A., Gillett, Sarah, McClure, Leslie A., Wadley, Virginia, Unverzagt, Fred, and Cushman, Marry. “ABO Blood Type, Factor VIII, and Incident Cognitive Impairment in the REGARDS Cohort.” Neurology. September 30, 2014 vol. 83 no. 14 1271-1276.
- American Red Cross. Blood Types.
Can Your Blood Type Affect Your Memory?
MINNEAPOLIS – People with blood type AB may be more ly to develop memory loss in later years than people with other blood types, according to a study published in the September 10, 2014, online issue of Neurology®, the medical journal of the American Academy of Neurology. AB is the least common blood type, found in about 4 percent of the U.S.
population. The study found that people with AB blood were 82 percent more ly to develop the thinking and memory problems that can lead to dementia than people with other blood types. Previous studies have shown that people with type O blood have a lower risk of heart disease and stroke, factors that can increase the risk of memory loss and dementia.
The study was part of a larger study (the REasons for Geographic And Racial Differences in Stroke, or REGARDS Study) of more than 30,000 people followed for an average of 3.4 years.
In those who had no memory or thinking problems at the beginning, the study identified 495 participants who developed thinking and memory problems, or cognitive impairment, during the study. They were compared to 587 people with no cognitive problems.
People with AB blood type made up 6 percent of the group who developed cognitive impairment, which is higher than the 4 percent found in the population.
“Our study looks at blood type and risk of cognitive impairment, but several studies have shown that factors such as high blood pressure, high cholesterol and diabetes increase the risk of cognitive impairment and dementia,” said study author Mary Cushman, MD, MSc, of the University of Vermont College of Medicine in Burlington.
“Blood type is also related to other vascular conditions stroke, so the findings highlight the connections between vascular issues and brain health. More research is needed to confirm these results.” Researchers also looked at blood levels of factor VIII, a protein that helps blood to clot.
High levels of factor VIII are related to higher risk of cognitive impairment and dementia. People in this study with higher levels of factor VIII were 24 percent more ly to develop thinking and memory problems than people with lower levels of the protein. People with AB blood had a higher average level of factor VIII than people with other blood types. The study was supported by the National Institute of Neurological Disorders and Stroke, National Institutes of Health, U.S. Department of Health and Human Services and National Heart, Lung, and Blood Institute. Learn more about brain health at AAN.com/patients.
The American Academy of Neurology is the world's largest association of neurologists and neuroscience professionals, with 36,000 members. The AAN is dedicated to promoting the highest quality patient-centered neurologic care.
A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer's disease, stroke, migraine, multiple sclerosis, concussion, Parkinson's disease and epilepsy.
For more information about the American Academy of Neurology, visit AAN.com or find us on , , LinkedIn, Instagram and .
People with blood type AB more at risk of cognitive decline and dementia
As the number of elderly people increases, so do concerns about cognitive impairment and dementia. Minor difficulties with memory and thinking can be a normal part of the ageing process, but our recent work found that people with the blood type AB may be at higher risk for significant cognitive problems than the rest of the population.
There are four main ABO blood system types: A, B, AB and O, which are determined by the presence of certain molecules (A and B antigens) on the surface of red blood cells. Of these, type AB is by far the least common, found in only about 4% of people in the US.
Our research group at the University of Vermont, led by Mary Cushman, found that the odds of developing cognitive impairment were 82% higher in those with blood type AB, compared to those with blood type O, which had the lowest risk. These results, which were published in Neurology, build on previous research showing that people with blood type O are at lower risk for cardiovascular diseases, including stroke.
We used information gathered from a larger study on stroke risk factors known as the Reasons for Geographic and Racial Differences in Stroke (REGARDS) Study, which followed more than 30,000 people from around the US who were aged 45 and above, for an average of 3.4 years.
In this time, 495 people developed cognitive impairment, characterised by thinking and memory problems. We compared this group with 587 individuals who did not develop cognitive problems.
In the group with cognitive impairment, 6% had blood type AB, compared with 4% in the control group and in the general population.
We also looked at blood levels of a protein called factor VIII, which is involved in blood coagulation.
Elevated factor VIII is a risk factor for stroke and coronary artery disease and may also be related to dementia risk.
We found that people with blood type AB also had the highest levels of factor VIII, nearly 40% higher than people with blood type O. High factor VIII alone increased the risk of cognitive problems by nearly a quarter.
The gene that determines ABO blood type can cause differences in factor VIII levels by affecting the clearance of a carrier protein that circulates the blood attached to factor VIII.
This carrier protein is called von Willebrand factor (named after Erik von Willebrand, a Finnish doctor who first described a hereditary blood coagulation disease) and is also important for blood clotting and linked to cardiovascular disease.
The effect of blood type on coagulation proteins may be part of the connection between ABO type, cardiovascular disease, and cognition problems. However, the differences in factor VIII levels accounted for only about a fifth of extra risk of cognitive impairment we saw with blood type AB.
Blood links to other health problems
Non-O blood types have been linked to several forms of vascular disease, including heart attack and venous thromboembolism (a disease that includes deep vein thrombosis). Blood type AB, in particular, has been associated with heart disease, and our group recently published a study showing a higher risk of stroke with this blood type.
Our findings on blood type and cognitive impairment add to a growing body of evidence that cardiovascular health and brain health are closely related. Many common risk factors for heart disease and stroke are also tied to memory problems and dementia, such as diabetes, high blood pressure, and high cholesterol.
Because blood type is already known to affect the risk of cardiovascular disease, it represents another link between vascular health and brain function.
With that in mind, there is no reason to panic if you have blood type AB. There are a number of lifestyle factors that can reduce your risk of cognitive problems and dementia, and many of them have more of an impact than your blood type.
Getting regular exercise, eating well and not smoking, for example, are important for both cardiovascular and brain health – and keeping blood pressure, cholesterol, and blood sugar under control will also lower your risk for these problems.
Scientists recommend keeping your brain active as well, through activities games and puzzles, and learning new skills.
Can your blood type protect you from getting dementia?
Published: 22:02 BST, 13 March 2017 | Updated: 01:59 BST, 14 March 2017
Science is revealing how having a particular blood type can play a crucial role in many aspects of health
Blood types are mysterious things — no one knows for sure why we have different groups, for instance.
Yet science is revealing how having a particular blood type can play a crucial hidden role in many aspects of health, from our chances of suffering sex and fertility problems, to whether we develop Alzheimer’s, lethal blood clots or even cancer.
The difference between blood groups is down to a combination of sugars and proteins that coat red blood cells.
this, we can all be classified into one of four main groups: A, B, AB and O. Around 44 per cent of Britons are type O, 42 per cent are type A, 10 per cent type B and 4 per cent AB.
A study published last week suggests that men with type O are four times less ly to experience impotence than men with blood types A, B or AB. According to the research, by Ordu University in Turkey and published in the journal Archives of Italian Urology and Andrology, blood type may be as important a risk factor for impotence as smoking, being overweight, and high blood pressure.
Although the exact reason is unclear, scientists said the penis has one of the highest amounts of veins in the body, and that something in blood type A may damage the lining of these veins, causing erectile dysfunction.
Fewer than half of English adults know their blood type, according to the NHS Blood and Transplant service, and many of us only find it out when we give blood.
Yet knowing our group may help us protect our own health. For although it is not clear why these groups emerged, it is known some blood types offer defence against different diseases.
For example, studies by the University of Toronto in 2014 indicate that people with type O are better protected against severe malaria than other blood types.
Blood type also affects female fertility and type A seems to be significantly better than type O
This seems to be because human immune cells are better able to recognise infected type-O blood cells than other types, and are more ly to target them.
But immunity seems to be only part of the story. Blood type also affects female fertility, and type A seems to be significantly better than type O. Studies have consistently found that women with type-O blood exhaust their body’s store of eggs earlier in life.
A 2011 Yale University study of more than 560 women in their mid-30s having fertility treatment found those with type O were twice as ly to have a lower egg count and poorer egg quality than those with group A. Researchers said this meant that they were less ly to become pregnant.
Separate research suggests that the hereditary genes which determine type O blood may also be responsible for this premature egg depletion.
There is some good fertility news for women with type O blood, however. Last year an Italian study, in the journal Blood Transfusions, found that they have a lower risk of pre-eclampsia — high blood pressure in pregnancy, which can be dangerous for mother and baby — than women with other blood groups.
Having type-O blood has another advantage in that it appears to reduce people’s risk of degenerative brain diseases such as Alzheimer’s.
Following brain scans on 189 Britons, researchers at Sheffield University discovered that those with type-O blood have more grey matter (which processes information) in crucial areas associated with speech, coordination and balance than those with type A and B blood.
‘We think that grey-matter levels are linked with the genetic factors that determine a person’s blood group,’ says Annalena Venneri, a professor of clinical neuropsychology who conducted the 2015 study. ‘These seem to affect how their brain develops.’
She adds that because type-O people develop more grey matter when young, they can afford to lose more of it in old age without developing dementia.
Indeed, a 2014 study of 495 people in the journal Neurology found that people with type O had a lower risk of developing cognitive impairment than those with types A and B. Professor Venneri says education, diet and exercise can also protect against the effects of losing grey matter, so it may be good to concentrate advice about this on people in non-O groups.
‘We could suggest to these people that, as a preventive measure, they should do more stimulating brain activities to counteract their blood-group,’ she told Good Health. ‘A healthy diet and exercise could help, too.’
A similar picture emerges with regards to potentially lethal artery and vein blockages.
In the journal Circulation last year, a five-year study of 1.5 million blood donors in Denmark and Sweden found that those with type O blood had around a 30 per cent lower risk than other blood types of developing clots that cause deep vein thrombosis, thromboembolisms (obstruction of a blood vessel in the body), and pulmonary embolisms (blockage of an artery in the lungs).
Around 44 per cent of Britons are type O, 42 per cent are type A, 10 per cent type B and 4 per cent AB
Furthermore, research shows that people with type B are far more ly than other blood groups to suffer recurrent thrombo- embolisms, though the reason is not yet understood.
These findings may help to explain why having type-B blood has been linked to an increased risk of premature death.
Type O also seems to have a protective effect against some cancers, such as stomach and liver cancer, studies suggest.
This growing body of compelling evidence might seem to support the fad for ‘blood-type’ diets, where popular books have encouraged people to stick to food regimes that ‘suit’ their group.
Some proponents recommend, for example, that people with type-O blood consume meals high in protein and fat, as their bodies are somehow configured to process these ingredients efficiently.
Not so, conclude nutritionists at Toronto University. In 2014 they studied 1,400 people on blood-type diets. They did find that their general health improved after months on the diets.
But it didn’t matter which blood-type regimen a person was on — or even if it matched their own blood type — the improvements were much the same. This was because the dietary regimens were themselves all quite healthy.
The Canadians declared in the journal PLoS One: ‘Our findings do not support the “Blood-Type” diet hypothesis.’
ABO blood group and neurodegenerative disorders: more than a casual association
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