Alzheimer’s disease is a neurological disorder which causes memory loss and cognitive impairment by the death of brain cells.
There were 6.8 million people living with dementia in the U.S. in 2013. Among those 5 million had an Alzheimer’s diagnosis. The numbers are to double by 2050.
Alzheimer’s is an disorder which is neurodegenerative. Symptoms are mild at first but they get more serious over time.
Fast facts on Alzheimer’s disease
- Alzheimer’s disease is the most common type of dementia.
- It happens when plaques containing beta amyloid form in the brain.
- As symptoms worsen, it becomes harder for people to remember recent events, to reason, and to recognize people they know.
- Eventually, a person with Alzheimer’s is likely to need full-time assistance.
To order to obtain an Alzheimer’s diagnosis, the person most have undergone a deterioration to cognitive or behavioral ability and results as opposed to how they were before. This deterioration continues to conflict with their ability to operate at work or in daily activities.
The cognitive impairment must be seen in two or more of the five areas of symptoms mentioned below:
1. Reduced ability to acquire and maintain new knowledge that, for example, can contribute to:
- repetitive questions or conversations
- misplacing personal belongings
- forgetting events or appointments
- getting lost on a familiar route
2. Impairments to reasoning, complex tasking, and exercising judgment, for example:
- poor understanding of safety risks
- inability to manage finances
- poor decision-making ability
- inability to plan complex or sequential activities
3. Impaired visuospatial abilities that are not, for example, due to eye sight problems. These could be:
- inability to recognize faces or common objects or to find objects in direct view
- inability to use simple tools, for example, to orient clothing to the body
4. Impaired speaking, reading and writing, for example:
- difficulty thinking of common words while speaking, hesitations
- speech, spelling, and writing errors
5. Changes in personality and behavior, for example:
- out-of-character mood changes, including agitation, apathy, social withdrawal or a lack of interest, motivation, or initiative
- loss of empathy
- compulsive, obsessive, or socially unacceptable behavior
If the number and severity of symptoms confirm dementia, the following factors can then confirm Alzheimer’s.
- a gradual onset, over months to years, rather than hours or days
- a marked worsening of the individual’s normal level of cognition in particular areas
If symptoms start or escalate over hours or days you should seek urgent medical treatment as this can suggest an acute disease.
Alzheimer’s is most likely when memory loss is a prominent symptom, especially in the field of learning and new knowledge being remembered.
Language challenges can also be a crucial early symptom, like failing to find the right words.
If the most influential visuospatial deficits are, these may include:
- inability to recognize objects and faces
- difficulty comprehending separate parts of a scene at once
- difficulty with reading text, known as alexia
The most famous executive disability deficits may have to do with reasoning, judgment and problem-solving.
Other early signs
Researchers released results in 2016 suggesting that an early signs of Alzheimer’s may be a shift of sense of humour.
Latest research indicates that Alzheimer’s manifestations, such as brain abnormalities, may already be present in midlife, while signs of the disorder occur only years later.
Early-onset Alzheimer’s disease
Early-onset familial Alzheimer’s disease, usually between the ages of 30 and 60, may affect younger people with a family history of the disease.
It constitutes fewer than 5 percent of all cases involving Alzheimer’s.
The progression of Alzheimer’s can be broken down into three main stages:
- preclinical, before symptoms appear
- mild cognitive impairment, when symptoms are mild
The Alzheimer’s Association also identifies seven stages along a continuum of cognitive impairment, based on severity of the symptoms.
The scale varies from a state of no disability, through mild and moderate decline, ultimately reaching “extremely extreme decline.” A diagnosis typically does not become apparent until stage four, described as “mild or early Alzheimer’s.”
Alzheimer’s versus dementia
Dementia is a paragliding term for a range of conditions which include a loss of cognitive function.
The most prevalent form of dementia is in Alzheimer’s. This includes the development of plaques and tangles within the brain. Symptoms start slowly and will most likely involve a decrease in cognitive function and ability to speak language.
Huntington’s disease, Parkinson’s disease, and Creutzfeldt-Jakob disease are other forms of dementia. People may experience more than one form of dementia.
Researchers can also check the neurological function of the person, by checking their balance, senses, and reflexes, for example.
Other tests may include a blood or urine check, a brain CT or MRI scan, and depression screening.
Often the dementia symptoms are linked to an inherited illness like Huntington’s disease, and genetic testing can be performed.
The doctor must administer cognitive and memory tests after ruling out any potential factors, in order to determine the person’s ability to think and recall.
To confirm a diagnosis of Alzheimer’s, the following must be present and severe enough to affect daily activities:
- gradual memory loss
- progressive cognitive impairment
Questions that may be asked to test cognitive ability include:
- What is your age?
- What is the time, to the nearest hour?
- What is the year?
- What is the name of the hospital or town we are in?
- Can you recognize two people, for example, the doctor, nurse, or carer?
- What is your date of birth?
- In which year did (a well-known historical event) happen?
- Name the president.
- Count backward from 20 down to 1
- Repeat an address at the end of the test that I will give you now (for example, “42 West Street”)
A number of assessment tools are available to assess cognitive function.
In certain cases it might be necessary to do genetic testing.
A gene known as the APOE-e4 is associated with increased risk of developing Alzheimer’s in people over the age of 55.
Early use of this test may suggest the possibility of someone getting the disease or developing it. The study is controversial, however, and the findings aren’t absolutely accurate.
Emerging biological tests that allow the assessment of biomarkers in people who may be at risk for Alzheimer’s in the future.
Alzheimer’s has no known remedy. Can’t stop the death of brain cells.
However, there are therapeutic interventions that can make it easier for people to live with the disease.
The following are critical components of dementia treatment according to Alzheimer’s Association:
- effective management of any conditions occurring alongside the Alzheimer’s
- activities and day-care programs
- involvement of support groups and services
There are no disease-modifying medications available for Alzheimer’s disease, but there are several treatments that can reduce the symptoms and help improve quality of life.
Inhibitors of cholinesterase approved for symptomatic relief in the US include:
- Donepezil (Aricept)
- Rivastigmine (Exelon)
- Tacrine (Cognex)
A different kind of drug, memantine (Namenda), an NMDA receptor antagonist, may also be used, alone or in combination with a cholinesterase inhibitor.
As the individual is less able to live independently, the need for quality-of-life treatment becomes more important.
Results of a mouse study published in Nature in 2016 indicated that memories for people with early Alzheimer’s may one day be recovered.
Causes and risk factors
Alzheimer’s, like any form of dementia, is caused by brain cell death. It is a neurodegenerative disorder, meaning that over time there is gradual mortality of the brain cells.
In an Alzheimer’s individual the tissue has fewer and fewer nerve cells and connections.
Autopsies have shown that a person with Alzheimer’s nerve tissue in the brain has tiny deposits, called plaques and tangles, that build up on the tissue.
In the dying brain cells, the plaques are located and made of a protein known as beta-amyloid.
Researchers do not completely understand why such improvements are taking place. There are known to be a variety of different factors involved.
The Alzheimer’s Association has created a 16-slide journey that visualizes what happens during the process of Alzheimer’s disease development. You will get into it here.
Unavoidable risk factors for developing the condition include:
- a family history of Alzheimer’s
- carrying certain genes
Modifiable factors that may help prevent Alzheimer’s include:
- getting regular exercise
- maintaining a healthy cardiovascular system
- managing the risk of cardiovascular disease, diabetes, obesity, smoking, and high blood pressure
- following a varied and healthful diet
- participating in lifelong learning and cognitive training
Some research indicate that remaining active mentally and socially may theoretically reduce the risk of Alzheimer’s.
Factors that increase the risk include:
- undergoing severe or repeated traumatic brain injuries (TBI)
- exposure to some environmental contaminants, such as toxic metals, pesticide, and industrial chemicals
In order to minimize the risk of TBI-related dementia, it is also necessary to wear a safety belt while traveling by car, to take care while playing contact sports, and to obey health instructions and recommendations to ensure sufficient rest and rehabilitation when an accident occurs.
A mild TBI tends to double the risk of dementia, while a extreme TBI raises the risk 4.5 fold.
Uses of vitamin B-12 level test: Normal ranges, and results
The amount of vitamin B-12 in the blood or urine is measured in a vitamin B-12 level test to determine the body’s overall vitamin B-12 reserves.
Vitamin B-12 is required for a variety of body functions, including neuron function, DNA and red blood cell formation.
Treatment is required if a person’s vitamin B-12 levels fall outside of the usual range. Vitamin B12 deficiency can cause neurological symptoms as well as fatigue, constipation, and weight loss. B-12 levels that are too high could indicate liver disease, diabetes, or another condition.
Continue reading to learn more about B-12 testing and what the results indicate.
Purpose of a vitamin B-12 level test
The vitamin B-12 level test determines the amount of vitamin B-12 in your body. Doctors can use the data to see if low vitamin B-12 levels are causing symptoms.
If a person exhibits any of the following symptoms, a doctor may recommend a vitamin B-12 level test:
Vitamin B-12 insufficiency
Vitamin B-12 deficiency is thought to affect up to 15% of people in the United States, according to research. The following are signs and symptoms of a deficiency:
- fast heartbeat
- numbness and tingling in the hands and feet
- poor memory
- a sore mouth or tongue
- difficulty maintaining balance
Vitamin B-12 deficiency in infants can cause them to underachieve. They may have mobility issues in addition to developmental delays.
A vitamin B-12 level test may be required for people who have signs of low iron. Pernicious anaemia is caused by a lack of vitamin B-12 absorption, resulting in poor red blood cell causes.
It usually affects the elderly or people who are deficient in intrinsic factor. Intrinsic factor is a gastric material that binds to vitamin B-12 and allows it to be absorbed by the body.
The following are signs and symptoms of pernicious anaemia:
- pale skin
- weight loss
- loss of appetite
High levels of folate in the blood
They can also make you more susceptible to anaemia.
Symptoms of other illnesses
Vitamin B-12 levels that are unusually high can be a symptom of liver disease, diabetes, or certain types of leukaemia. The findings of a vitamin B-12 test may be used by a doctor to help them make a diagnosis.
Vitamin B-12 deficiency is more common in some people than in others, especially those with low stomach acid or other digestive problems. Stomach acid helps the body absorb vitamin B-12 more effectively by separating it from meals.
Low vitamin B-12 levels are more common in the following groups of people than in others:
- people with conditions that reduce vitamin B-12 absorption, including celiac disease and Crohn’s disease
- people who have had gastric bypass surgery
- those who are breast-feeding
- people who are taking medicines such as chloramphenicol, proton pump inhibitors, or H2 blockers
- older adults
- vegans and vegetarians
- people with diabetes
How does the B-12 vitamin level test work?
Vitamin B-12 status is normally determined by a blood test, but home urine tests are now available. Vitamin B-12 levels can be checked as part of a routine blood test by a doctor.
Although fasting is not required before a B-12 test, it may be necessary if the doctor is utilising the test to check at other blood components.
It is important that patients inform their doctors about any medications or supplements they are taking, as some may have an impact on the outcome.
Acknowledging the results
The following are possible results:
- Low. Vitamin B-12 levels below 200 pg/mL are considered low. This indicates that you may have a vitamin B-12 deficiency, pernicious anaemia, or an overactive thyroid. Neurological symptoms are common in people who have low vitamin B-12 levels.
- High. Anything over 900 pg/mL is considered excessively high vitamin B-12 status. This result could indicate problems with the liver or kidneys, diabetes, or certain types of leukaemia.
Because the ranges of results differ from one laboratory to the next, it’s important to talk to a doctor about the results and what they signify.
To rule out vitamin B-12 deficiency, the doctor may measure levels of methylmalonic acid (MMA) and other chemicals. These lab results aid in the early detection of vitamin B-12 deficiency.
Vitamin B-12 deficiency treatment
Vitamin B-12 injections are frequently required by people who have low amounts of the vitamin. These shots are more successful at boosting vitamin B-12 levels than supplements, especially when people have medical issues that make supplements difficult to absorb.
High doses of vitamin B-12 supplements may help some people improve their B-12 status. Supplements are sold in the form of capsules or liquids in pharmacies, supermarkets, health food stores. It may also be beneficial to consume extra vitamin B-12-rich foods.
Treatment for high vitamin B-12 levels
There is no upper limit on vitamin B-12 consumption because high amounts do not cause problems. Having naturally high levels of vitamin B-12 in the body, on the other hand, could be cause for alarm, since it could indicate a serious underlying condition. Doctors will focus on treating the underlying medical condition rather than the vitamin B-12 levels.
Vitamin B-12 foods.
Although low vitamin B-12 levels are frequently caused by absorption problems and other medical conditions, some people may be deficient because they do not acquire enough vitamin B-12 through their food. This is especially true for vegans and vegetarians who have been vegetarian for a long time.
Vitamin B-12-rich foods include:
- fortified plant-based dairy alternatives
- fortified breakfast cereals
- fortified nutritional yeast
- fish and seafood
- dairy products
Vitamin supplements can help vegans and strict vegetarians make up for dietary deficiencies. Older persons should seek to achieve their vitamin B-12 needs through fortified meals and vitamin supplements, as supplements are simpler for their bodies to absorb than naturally occurring vitamin B-12.
Vitamin B-12 dietary recommendations
Vitamin B-12 is required in 2.4 micrograms (mcg) per day for adults and adolescents over the age of 14. During pregnancy, this rises to 2.6 mcg, and breast-feeding raises it to 2.8 mcg.
Vitamin B-12 is an essential nutrient that is necessary for good health. The status of a person’s vitamin B-12 is determined by a vitamin B-12 level test. This test may be recommended by a doctor to people who have symptoms of a deficiency or who are at risk of having low vitamin B-12 levels in their bodies.
Vitamin B-12 deficiency can be avoided by eating a well-balanced diet that includes many sources of the vitamin on a daily basis, or by taking supplements. If they have trouble absorbing vitamin B-12 from food, oral supplements or injections can help them avoid symptoms and consequences.
What are the signs and symptoms of Alzheimer’s disease in its early stages?
Alzheimer’s disease is a type of dementia that affects mostly older people. Alzheimer’s disease strikes people before they reach the age of 65.
Alzheimer’s disease causes memory loss as well as a slew of other symptoms. It is a progressive condition, meaning that the symptoms will worsen over time. The most frequent type of dementia is Alzheimer’s disease.
Experts assume that early-onset Alzheimer’s disease accounts for fewer than 10 percent of all cases. It is usually caused by an inherited genetic trait. It usually appears in people in their 40s or 50s, but it can start as early as their 30s.
Although there is currently no cure, medication can help manage symptoms and slow the condition’s progression.
The symptoms, causes, and treatment options related to early-onset Alzheimer’s disease are discussed in this article.
Providing assistance to a loved one
People can help a loved one with Alzheimer’s disease in a variety of ways. They could, for example, try:
- To gain a better grasp of the person’s situation, learn about Alzheimer’s disease.
- speaking with the individual and partaking in activities that are enjoyable to both parties.
- providing practical assistance, such as food preparation or transportation to appointments
- through support networks, you can connect with other people.
- keeping in mind that this is the same person.
- enquiring about the person’s well-being.
- talking to a counselor or another trustworthy person about your changing relationship is a good idea.
According to Genetics Home Reference, genetic factors are most likely to blame for early onset Alzheimer’s disease.
Some people are born with mutations in specific genes and acquire familial Alzheimer’s disease at a young age. The alterations cause the brain to create harmful proteins, which stack up in the brain and form amyloid plaques, which are clumps of protein.
The genes are passed down through the generations in an autosomal dominant pattern, which means that a person only has to inherit one copy of the mutated gene from a parent to acquire the condition. Frequently, the father suffers from the same condition.
Others don’t have these modifications, and it’s unclear why some people have the condition; nevertheless, additional genes may be implicated.
Symptoms and signs
Memory loss is the most common symptom of Alzheimer’s disease, but other changes can also occur. Other types of dementia can have symptoms that are similar to Alzheimer’s disease, and other illnesses can cause symptoms that are similar to Alzheimer’s disease.
The following are some of the most common signs and symptoms.
1. Impaired daily tasks due to memory loss
Memory loss is frequently the most visible indication of Alzheimer’s disease. A person may begin to forget communications or recent occurrences in ways that are out of character for them. They may ask the same question again, forgetting either the answer or the fact that they asked it previously.
People forget things as they become older, but with early-onset Alzheimer’s disease, this happens earlier in life, more frequently, and appears out of character.
2. Difficulty carrying out routine tasks
It’s possible that the person will struggle to complete a task that they’re used to. For example, they may struggle to:
- prepare a simple meal
- follow the rules of a familiar game
- get to a grocery store, restaurant, or place of employment
As people get older, they may want assistance with new or unfamiliar items, such as the settings on a new phone. This, however, does not always imply a problem.
If, on the other hand, the person has been using the same phone for years and suddenly forgets how to make a phone call, they may be suffering from Alzheimer’s disease-related memory loss.
3. Difficulties with problem-solving or planning
Following directions, solving issues, and concentration may be challenging for the individual. They could find it challenging, for example, to:
- keep track of monthly bills or expenses
- follow directions on a product
- follow a recipe
These issues are common in some people, but if they begin to occur when they did not previously, it could suggest early onset Alzheimer’s disease.
4. Vision and spatial awareness problems
Vision impairments associated with Alzheimer’s disease might cause it difficult for people to assess distances between objects. The person may have difficulty distinguishing contrast and colors, as well as judging speed and distance.
The combination of these eyesight issues can impair a person’s ability to drive.
Because normal aging impairs eyesight, it’s critical to see an eye doctor on a frequent basis.
5. Confusion over time and location
The person may be unsure of where they are or what time it is. Seasons, months, and times of day may be difficult for them to remember.
In a strange environment, they may become perplexed. They may become confused in familiar settings or wonder how they got there as Alzheimer’s disease worsens. They may also begin to wander and become disoriented.
6. Misplacing stuff frequently and being unable to retrace steps
Most people lose things from time to time, but they can generally find them by searching in logical places and retracing their actions.
Someone with Alzheimer’s disease, on the other hand, may forget where they put something, especially if it’s in an unusual location. They may also be unable to track down the missing object by retracing their steps. This might be upsetting and cause to the victim believing that someone is robbing them.
7. Issues with writing or speaking
Words and communication may also be a problem for the individual. They could have trouble following or contributing to a conversation, or they might keep repeating themselves. It’s also possible that the person has trouble writing down their thoughts.
They might come to a halt in the middle of a conversation, unsure of what to say next. They could also have trouble finding the right word or mislabel things.
It is not uncommon for people to have difficulty finding the proper word at times. They usually remember it after a while and don’t have the problem again.
8. Symptoms of reduced judgment
The person’s ability to make sound decisions may have shifted. For instance, they could begin by saying:
- Spending a lot of time on chores that aren’t necessary.
- displaying a lack of interest in personal grooming, including washing
- putting items away in unexpected places, such as placing keys in the refrigerator
9. Mood swings or personality changes
A person with Alzheimer’s disease may notice a change in their mood. They may be irritated, perplexed, worried, or melancholy. They may also lose interest in activities that they previously enjoyed.
They may become annoyed by their symptoms or unable to comprehend the changes that are occurring. Aggression or anger toward others could be a sign of this.
10. Stepping away from social or work activities
As Alzheimer’s disease progresses, a person’s ability to participate in social or work activities may diminish.
|Memory loss||Forgetting things and repeating questions in a way that is unusual||Slowly becoming more forgetful|
|Completing tasks||Difficulty completing familiar tasks such as buying groceries or preparing food||Potentially needing help with new or unfamiliar things such as new technology|
|Problem-solving||Difficulty following instructions such as a new recipe or keeping track of bills||Being a little slower to react to things or juggle multiple tasks|
|Vision||Problems with vision and spatial awareness||Decreasing clarity of vision that may make it harder to distinguish shapes from a distance|
|Timekeeping||Difficulty keeping track of what day it is and becoming confused in an unfamiliar place||Forgetting the reason for entering a room before remembering again|
|Misplacing items||Misplacing items in unusual places and struggling to retrace steps||Momentarily misplacing items before remembering where to find them|
|Communication||Losing track of conversations, repeating sentences, and struggling to write down thoughts||Occasionally struggling to find the right word or needing to concentrate harder to keep up with conversation|
|Decision making||Spending a long time doing unnecessary tasks and neglecting personal grooming||Being a little slower in decision making|
|Mood changes||Experiencing low moods and feelings of irritableness, anxiety, confusion, and depression||Sometimes feeling weary or becoming irritable when there is disruption to a routine|
|Socializing||No longer participating in social activities that previously brought enjoyment||Sometimes feeling tired and worn out by social interactions|
If a person develops one or more of the symptoms listed above, they should see a doctor very away. Early detection may assist to slow the condition’s progression.
Because there is no definite test for Alzheimer’s disease at this time, a doctor will diagnose it based on the symptoms that can be seen. They could try:
- asking certain questions to the person, such as where they live, and evaluating their answers
- conversing with family members to learn about the person’s actions.
- taking into account the individual’s personal and family medical history
- performing various tests to rule out other probable causes, such as blood tests and brain imaging
Because there is presently no cure for Alzheimer’s disease, treatment focuses on symptom management. Among the treatment options available are:
- cognitive stimulation therapy, which may help with memory, speech, and problem solving
- support for living independently
- treatments for insomnia
- behavioral therapy to make life easier for the individual and their loved ones or caregivers
- medications to help with memory loss and possibly slow the progression of the condition
- counseling or medications to help manage depression or anxiety
Better therapy alternatives are constantly being researched.
After being diagnosed with Alzheimer’s disease, most people can expect to survive for another 8–10 years, however the outlook varies from 1–25 years. It will be influenced by the person’s age at the time of diagnosis, with younger people often living longer.
Pneumonia, malnutrition, or body wasting are common causes of mortality.
Alzheimer’s disease has no cure at this time, however medication can help manage the symptoms.
Alzheimer’s disease is more likely to develop as people get older, but people with a family history of the disease may be at a higher risk.
Anyone who feels they or a loved one is suffering from Alzheimer’s disease should consult a physician.
Is there a link between TBI and dementia?
The question of whether traumatic brain injury causes dementia has long been debated, and the results of various research are sometimes contradictory. However, there is increasing evidence that severe brain injury can result in long-term brain damage.
Traumatic brain injuries (TBIs) cause the brain’s normal function to be disrupted. According to the Centers for Disease Control and Prevention, they are caused by a blow or jolt to the skull, or an injury that penetrates it (CDC).
In the United States in 2013, 2.8 million people had a TBI, with around 56,000 of them dying. Small children under the age of four, teens and young adults between the ages of 14 and 25, and people over the age of 75 were the age groups most impacted by TBI. Falls, being struck by an item, and automobile accidents were the most prevalent causes of TBI.
Headaches, blurred vision, slurred speech, and short-term memory impairments are just a few of the early symptoms. TBIs can potentially have long-term health consequences, including an increased risk of seizures and infections.
TBI has been linked to numerous kinds of progressive neurodegeneration, including dementia, Alzheimer’s disease, amyotrophic lateral sclerosis (ALS), and Parkinson’s disease, according to research, however the evidence is mixed.
Why is it so difficult to come up with irrefutable proof? What are the long-term prospects for TBI victims?
The latest findings
The researchers reviewed medical notes of working-age adults under the age of 65 who had mild or moderate to severe TBI and later got dementia, Parkinson’s disease, or ALS, using the Finnish Care Register for Health Care.
They detected a correlation between moderate to severe TBI and dementia, but no such association was found with Parkinson’s disease or ALS.
Importantly, they discovered that dementia rates in moderate to severe TBI patients were comparable to those in the general population. However, dementia primarily affects the elderly, indicating that TBI raises the risk from old age to working age.
Finland has a tax-funded healthcare system, hence the dataset utilized in this study was extensive. All acute TBI cases are treated in public hospitals, according to the authors, and hence would have been included in the research.
However, data was only accessible for TBI patients who had been hospitalized to the hospital with neurodegenerative symptoms afterward. Other individuals with a diagnosis of neurodegeneration may have been overlooked if they had not been hospitalized at the time, according to the authors.
The findings of the Finnish study matched data published in the Asian Pacific Journal of Public Health last year. Dementia rates were greater among Taiwanese TBI patients than among non-TBI patients in this study.
Another research, just published in the Journal of Alzheimer’s Disease, found no association between TBI and Alzheimer’s disease.
The scientists studied 706 seniors in the United States with and without TBI and discovered that TBI had no effect on cognitive deterioration. However, because TBI was self-reported rather than assessed in the research participants’ medical records, the results may not have been reliable.
The Annals of Physical and Rehabilitation Medicine released a systematic study earlier this year that struggled to identify a relevant link between TBI and Alzheimer’s disease.
Although the evaluation contained 18 trials, the authors were unable to categorize TBI according to severity. It may not have been able to establish a link between TBI and Alzheimer’s disease if mild and moderate to severe TBI were lumped together.
Other disease, on the other hand, has discovered clear correlations between TBI and Alzheimer’s and Parkinson’s disease.
TBI, neurodegeneration link supported
According to a recent study published in the journal The Clinical Neuropsychologist, people with histories of moderate to severe TBI began to experience symptoms and obtained their diagnosis 2.5 years earlier than non-TBI patients in an Alzheimer’s disease patient cohort. However, in this study, TBI was self-reported.
While there was no association between TBI and dementia or Alzheimer’s disease, there was a correlation with Parkinson’s disease, according to a study published in JAMA Neurology last year.
After their deaths, several of the research participants agreed to have their brains autopsied. Both mild and moderate to severe TBI patients displayed evidence of Lewy bodies, a hallmark of Parkinson’s disease, in their brains, as well as signs of cerebral microinfarcts in the moderate to severe TBI patients.
Importantly, while the majority of research participants were 65 and older, a third of mild TBI patients and almost half of moderate to severe TBI patients were 25 or younger at the time of their injury. This shows that TBI may have long-term neurodegenerative consequences.
The difficulty with this sort of study is that it relies heavily on association measurements. This implies that researchers use data to determine whether or if there is a relationship between TBI and neurodegeneration in a certain study group.
However, because cause and effect cannot be shown in these investigations, additional biological pathways may be implicated in producing neurodegeneration in these patients.
Animals are used by researchers to investigate what occurs in the brain after a TBI. The events that followed TBI are starting to be pieced together here.
How can TBI cause neurodegeneration?
A recent paper in Reviews in the Neurosciences detailed what is known about the neurological damage that occurs after a TBI to date.
Blood arteries, neurons, and other cell types are all damaged in the first insult. Neurons get overstimulated as a side consequence, resulting in oxidative stress and cell death. The brain’s water metabolism is also disrupted, resulting in edema.
The blood-brain barrier is compromised, enabling immune cells to invade the injured brain, which is ordinarily resistant to most drugs.
The brain can be permanently harmed by a combination of oxidative damage, neuroinflammation, edema, and poor blood flow.
A recent research published in The Journal of Neuroscience used a mouse model of brain damage to analyze the long-term repercussions of TBI in greater depth.
The areas surrounding the injury site suffered immediate damage. Importantly, persistent neuroinflammation was found to cause long-term damage in distant areas of the brain.
Long-term consequences following TBI were also detected in a mouse model of Alzheimer’s disease, according to a study published in Neuroscience Letters. There were no immediate alterations in the brains of older mice who had received TBI vs those who had not.
For the first week of the trial, both wounded and uninjured mice acquired senile plaques, a characteristic of Alzheimer’s disease. The mice, on the other hand, had much more plaques 28 days after the TBI. There was also a problem with spatial learning.
The researchers deduced that TBI hastens the onset of Alzheimer’s disease symptoms.
What do these findings imply for people who have had a TBI?
The need for long-term monitoring
While it is feasible to examine the cellular processes that occur after TBI in model systems, applying these findings to real patients is more problematic.
Many studies show that TBI has long-term repercussions on the brains of animals and people, but the amount of the damage and its consequences are unknown.
Regardless of their findings, most studies agree that TBI patients, particularly those who have suffered moderate to severe TBI, require long-term monitoring. There is also a request for more precise diagnostic criteria that would allow doctors to detect TBI-related neurodegeneration earlier.
This would allow doctors to keep a close eye on their patients and provide therapies or interventions as soon as possible, therefore delaying the process of cognitive deterioration.
More research is clearly needed, particularly studies that look into cause and effect and can relate the findings to large-scale, reliable demographic data.
It’s also important to keep in mind that not everyone who has had a TBI will develop progressive neurodegeneration.
A total of 1.6 percent of patients with a history of moderate TBI developed dementia in the Finnish research. Even while individuals with moderate to severe TBI were 90 percent more likely to be diagnosed with dementia, the rate was still just 3.5 percent.
While there is solid evidence that a TBI may cause long-term brain damage, concerns remain about why certain patients acquire progressive neurodegeneration and how many people are likely to be impacted.