Dementia is a term used to describe a group of symptoms affecting memory, thinking and social abilities severely enough to interfere with your daily life. It isn't a specific disease, but several diseases can cause dementia.
Though dementia generally involves memory loss, memory loss has different causes. Having memory loss alone doesn't mean you have dementia, although it's often one of the early signs of the condition.
Alzheimer's disease is the most common cause of a progressive dementia in older adults, but there are a number of other causes of dementia. Depending on the cause, some dementia symptoms might be reversible.
Dementia symptoms vary depending on the cause, but common signs and symptoms include:
- Memory loss, which is usually noticed by someone else
- Difficulty communicating or finding words
- Difficulty with visual and spatial abilities, such as getting lost while driving
- Difficulty reasoning or problem-solving
- Difficulty handling complex tasks
- Difficulty with planning and organizing
- Difficulty with coordination and motor functions
- Confusion and disorientation
- Personality changes
- Inappropriate behavior
When to see a doctor
See a doctor if you or a loved one has memory problems or other dementia symptoms. Some treatable medical conditions can cause dementia symptoms, so it's important to determine the cause.
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Dementia is caused by damage to or loss of nerve cells and their connections in the brain. Depending on the area of the brain that's damaged, dementia can affect people differently and cause different symptoms.
Dementias are often grouped by what they have in common, such as the protein or proteins deposited in the brain or the part of the brain that's affected. Some diseases look like dementias, such as those caused by a reaction to medications or vitamin deficiencies, and they might improve with treatment.
Types of dementias that progress and aren't reversible include:
Alzheimer's disease. This is the most common cause of dementia.
Although not all causes of Alzheimer's disease are known, experts do know that a small percentage are related to mutations of three genes, which can be passed down from parent to child. While several genes are probably involved in Alzheimer's disease, one important gene that increases risk is apolipoprotein E4 (APOE).
Alzheimer's disease patients have plaques and tangles in their brains. Plaques are clumps of a protein called beta-amyloid, and tangles are fibrous tangles made up of tau protein. It's thought that these clumps damage healthy neurons and the fibers connecting them.
Vascular dementia. This type of dementia is caused by damage to the vessels that supply blood to your brain. Blood vessel problems can cause strokes or affect the brain in other ways, such as by damaging the fibers in the white matter of the brain.
The most common signs of vascular dementia include difficulties with problem-solving, slowed thinking, and loss of focus and organization. These tend to be more noticeable than memory loss.
Lewy body dementia. Lewy bodies are abnormal balloonlike clumps of protein that have been found in the brains of people with Lewy body dementia, Alzheimer's disease and Parkinson's disease. This is one of the more common types of progressive dementia.(Video) Dementia: Causes, Symptoms and Treatment.
Common signs and symptoms include acting out one's dreams in sleep, seeing things that aren't there (visual hallucinations), and problems with focus and attention. Other signs include uncoordinated or slow movement, tremors, and rigidity (parkinsonism).
- Frontotemporal dementia. This is a group of diseases characterized by the breakdown of nerve cells and their connections in the frontal and temporal lobes of the brain. These are the areas generally associated with personality, behavior and language. Common symptoms affect behavior, personality, thinking, judgment, and language and movement.
- Mixed dementia. Autopsy studies of the brains of people 80 and older who had dementia indicate that many had a combination of several causes, such as Alzheimer's disease, vascular dementia and Lewy body dementia. Studies are ongoing to determine how having mixed dementia affects symptoms and treatments.
Other disorders linked to dementia
- Huntington's disease. Caused by a genetic mutation, this disease causes certain nerve cells in your brain and spinal cord to waste away. Signs and symptoms, including a severe decline in thinking (cognitive) skills, usually appear around age 30 or 40.
Traumatic brain injury (TBI). This condition is most often caused by repetitive head trauma. Boxers, football players or soldiers might develop TBI.
Depending on the part of the brain that's injured, this condition can cause dementia signs and symptoms such as depression, explosiveness, memory loss and impaired speech. TBI may also cause parkinsonism. Symptoms might not appear until years after the trauma.
Creutzfeldt-Jakob disease. This rare brain disorder usually occurs in people without known risk factors. This condition might be due to deposits of infectious proteins called prions. Signs and symptoms of this fatal condition usually appear after age 60.
Creutzfeldt-Jakob disease usually has no known cause but can be inherited. It may also be caused by exposure to diseased brain or nervous system tissue, such as from a cornea transplant.
- Parkinson's disease. Many people with Parkinson's disease eventually develop dementia symptoms (Parkinson's disease dementia).
Dementia-like conditions that can be reversed
Some causes of dementia or dementia-like symptoms can be reversed with treatment. They include:
- Infections and immune disorders. Dementia-like symptoms can result from fever or other side effects of your body's attempt to fight off an infection. Multiple sclerosis and other conditions caused by the body's immune system attacking nerve cells also can cause dementia.
- Metabolic problems and endocrine abnormalities. People with thyroid problems, low blood sugar (hypoglycemia), too little or too much sodium or calcium, or problems absorbing vitamin B-12 can develop dementia-like symptoms or other personality changes.
- Nutritional deficiencies. Not drinking enough liquids (dehydration); not getting enough thiamin (vitamin B-1), which is common in people with chronic alcoholism; and not getting enough vitamins B-6 and B-12 in your diet can cause dementia-like symptoms. Copper and vitamin E deficiencies also can cause dementia symptoms.
- Medication side effects. Side effects of medications, a reaction to a medication or an interaction of several medications can cause dementia-like symptoms.
- Subdural hematomas. Bleeding between the surface of the brain and the covering over the brain, which is common in the elderly after a fall, can cause symptoms similar to those of dementia.
- Brain tumors. Rarely, dementia can result from damage caused by a brain tumor.
- Normal-pressure hydrocephalus. This condition, which is caused by enlarged ventricles in the brain, can result in walking problems, urinary difficulty and memory loss.
Many factors can eventually contribute to dementia. Some factors, such as age, can't be changed. Others can be addressed to reduce your risk.
Risk factors that can't be changed
- Age. The risk rises as you age, especially after age 65. However, dementia isn't a normal part of aging, and dementia can occur in younger people.
- Family history. Having a family history of dementia puts you at greater risk of developing the condition. However, many people with a family history never develop symptoms, and many people without a family history do. There are tests to determine whether you have certain genetic mutations.
- Down syndrome. By middle age, many people with Down syndrome develop early-onset Alzheimer's disease.
Risk factors you can change
You might be able to control the following risk factors for dementia.
- Diet and exercise. Research shows that lack of exercise increases the risk of dementia. And while no specific diet is known to reduce dementia risk, research indicates a greater incidence of dementia in people who eat an unhealthy diet compared with those who follow a Mediterranean-style diet rich in produce, whole grains, nuts and seeds.
- Excessive alcohol use. Drinking large amounts of alcohol has long been known to cause brain changes. Several large studies and reviews found that alcohol use disorders were linked to an increased risk of dementia, particularly early-onset dementia.
- Cardiovascular risk factors. These include high blood pressure (hypertension), high cholesterol, buildup of fats in your artery walls (atherosclerosis) and obesity.
- Depression. Although not yet well-understood, late-life depression might indicate the development of dementia.
- Diabetes. Having diabetes may increase your risk of dementia, especially if it's poorly controlled.
- Smoking. Smoking might increase your risk of developing dementia and blood vessel diseases.
- Air pollution. Studies in animals have indicated that air pollution particulates can speed degeneration of the nervous system. And human studies have found that air pollution exposure — particularly from traffic exhaust and burning wood — is associated with greater dementia risk.
- Head trauma. People who've had a severe head trauma have a greater risk of Alzheimer's disease. Several large studies found that in people age 50 years or older who had a traumatic brain injury (TBI), the risk of dementia and Alzheimer's disease increased. The risk increases in people with more-severe and multiple TBIs. Some studies indicate that the risk may be greatest within the first six months to two years after the TBI.
- Sleep disturbances. People who have sleep apnea and other sleep disturbances might be at higher risk of developing dementia.
- Vitamin and nutritional deficiencies. Low levels of vitamin D, vitamin B-6, vitamin B-12 and folate can increase your risk of dementia.
Medications that can worsen memory. Try to avoid over-the-counter sleep aids that contain diphenhydramine (Advil PM, Aleve PM) and medications used to treat urinary urgency such as oxybutynin (Ditropan XL).
Also limit sedatives and sleeping tablets and talk to your doctor about whether any of the drugs you take might make your memory worse.(Video) Spotting the signs of dementia
Dementia can affect many body systems and, therefore, the ability to function. Dementia can lead to:
- Poor nutrition. Many people with dementia eventually reduce or stop eating, affecting their nutrient intake. Ultimately, they may be unable to chew and swallow.
- Pneumonia. Difficulty swallowing increases the risk of choking or aspirating food into the lungs, which can block breathing and cause pneumonia.
- Inability to perform self-care tasks. As dementia progresses, it can interfere with bathing, dressing, brushing hair or teeth, using the toilet independently, and taking medications as directed.
- Personal safety challenges. Some day-to-day situations can present safety issues for people with dementia, including driving, cooking, and walking and living alone.
- Death. Late-stage dementia results in coma and death, often from infection.
There's no sure way to prevent dementia, but there are steps you can take that might help. More research is needed, but it might be beneficial to do the following:
- Keep your mind active. Mentally stimulating activities, such as reading, solving puzzles and playing word games, and memory training might delay the onset of dementia and decrease its effects.
- Be physically and socially active. Physical activity and social interaction might delay the onset of dementia and reduce its symptoms. Aim for 150 minutes of exercise a week.
- Quit smoking. Some studies have shown that smoking in middle age and beyond might increase your risk of dementia and blood vessel conditions. Quitting smoking might reduce your risk and will improve your health.
Get enough vitamins. Some research suggests that people with low levels of vitamin D in their blood are more likely to develop Alzheimer's disease and other forms of dementia. You can get vitamin D through certain foods, supplements and sun exposure.
More study is needed before an increase in vitamin D intake is recommended for preventing dementia, but it's a good idea to make sure you get adequate vitamin D. Taking a daily B-complex vitamin and vitamin C also might help.
Manage cardiovascular risk factors. Treat high blood pressure, high cholesterol and diabetes. Lose weight if you're overweight.
High blood pressure might lead to a higher risk of some types of dementia. More research is needed to determine whether treating high blood pressure may reduce the risk of dementia.
- Treat health conditions. See your doctor for treatment for depression or anxiety.
- Maintain a healthy diet. A diet such as the Mediterranean diet — rich in fruits, vegetables, whole grains and omega-3 fatty acids, which are commonly found in certain fish and nuts — might promote health and lower your risk of developing dementia. This type of diet also improves cardiovascular health, which may help lower dementia risk.
- Get good-quality sleep. Practice good sleep hygiene, and talk to your doctor if you snore loudly or have periods where you stop breathing or gasp during sleep.
- Treat hearing problems. People with hearing loss have a greater chance of developing cognitive decline. Early treatment of hearing loss, such as use of hearing aids, might help decrease the risk.
By Mayo Clinic Staff
Oct. 12, 2022
This is the most common cause of dementia.
This is the most common cause of dementia, accounting for 60 to 80 percent of cases. It is caused by specific changes in the brain.
The average life expectancy figures for the most common types of dementia are as follows: Alzheimer's disease – around eight to 10 years. Life expectancy is less if the person is diagnosed in their 80s or 90s. A few people with Alzheimer's live for longer, sometimes for 15 or even 20 years.What is the lifespan of dementia patients? ›
On average, a person with Alzheimer's lives four to eight years after diagnosis, but can live as long as 20 years, depending on other factors. Changes in the brain related to Alzheimer's begin years before any signs of the disease.What is the 3 word memory test? ›
The Mini-Cog test.
A third test, known as the Mini-Cog, takes 2 to 4 minutes to administer and involves asking patients to recall three words after drawing a picture of a clock. If a patient shows no difficulties recalling the words, it is inferred that he or she does not have dementia.
There is currently no cure for dementia. But there are medicines and other treatments that can help with dementia symptoms.Who's most likely to get dementia? ›
The biggest risk factor for dementia is ageing. This means as a person gets older, their risk of developing dementia increases a lot. For people aged between 65 and 69, around 2 in every 100 people have dementia. A person's risk then increases as they age, roughly doubling every five years.What is the 5 word memory test? ›
Introduction: The five-word test (5WT) is a serial verbal memory test with semantic cuing. It is proposed to rapidly evaluate memory of aging people and has previously shown its sensitivity and its specificity in identifying patients with AD.What is a quick test for dementia? ›
If you suspect that your older adult is having problems with memory, thinking, or judgement, you may want them to take the SAGE test for dementia. This at-home pen-and-paper test is free, takes just 15 minutes, and accurately identifies early symptoms of Alzheimer's disease or dementia.At what age does dementia usually begin? ›
For most people with Alzheimer's — those who have the late-onset variety — symptoms first appear in their mid-60s or later. When the disease develops before age 65, it's considered early-onset Alzheimer's, which can begin as early as a person's 30s, although this is rare.
A person with dementia's abilities may change from day to day, or even within the same day. What is certain though is that the person's abilities will deteriorate; this may happen rapidly in a period of a few months or slowly over a number of years.Does dementia run in families? ›
Many people affected by dementia are concerned that they may inherit or pass on dementia. The majority of dementia is not inherited by children and grandchildren. In rarer types of dementia there may be a strong genetic link, but these are only a tiny proportion of overall cases of dementia.What are signs that dementia is getting worse? ›
increasing confusion or poor judgment. greater memory loss, including a loss of events in the more distant past. needing assistance with tasks, such as getting dressed, bathing, and grooming. significant personality and behavior changes, often caused by agitation and unfounded suspicion.What do dementia patients think about? ›
People with dementia think about the same things that any human thinks about — emotions, relationships, daily life, tasks to accomplish, and more. Receiving a life-changing diagnosis of dementia does not strip a person of their humanity and personhood.Do dementia patients sleep a lot? ›
It is quite common for a person with dementia, especially in the later stages, to spend a lot of their time sleeping – both during the day and night. This can sometimes be distressing for the person's family and friends, as they may worry that something is wrong.What is the 5 minute recall test? ›
The five-minute cognitive test (FCT) was designed to capture deficits in five domains of cognitive abilities, including episodic memory, language fluency, time orientation, visuospatial function, and executive function.What does the Bible say about dementia? ›
Scripture assures us that nothing can separate us from the love of God, not even a dementia that may strip a person of her awareness of God's presence (Romans 8:38-29).What is the 15 word test? ›
The 15 Words Test (15WT) is developed to investigate episodic memory problems in patients with brain disorders. It is the Dutch version of the Auditory Verbal Learning Test (AVLT; Rey, 1964; Deelman et al. 1980; Saan RJ & Deelman BG. 1986).What slows down dementia? ›
Stay mentally and socially active. Engaging in mental or social activities may help to build up your brain's ability to cope with disease, relieve stress and improve your mood. This means doing these activities may help to delay, or even prevent, dementia from developing.How do you know the end is near with dementia? ›
Signs of the final stages of dementia include some of the following: Being unable to move around on one's own. Being unable to speak or make oneself understood. Eating problems such as difficulty swallowing.
Four medications are currently available for the treatment of AD, and all were approved more than a decade ago. Of these, the first-line agents are the acetylcholinesterase (AChE) inhibitors donepezil, rivastigmine, and galantamine.What sleeping position is linked to dementia? ›
A 2019 study published in Journal of Alzheimer's Disease, showed among 165 participants (45 with diagnosed neurodegenerative disease, 120 controls) a supine sleep position (on back, head at body level) for more than 2 hours per night increased the risk of dementia by almost four times (3.7 times greater).What can accelerate dementia? ›
- Autoimmune diseases (conditions that over-activate the immune system)
- Unusual presentations of more common neurodegenerative diseases (such as Alzheimer's disease)
- Prion diseases (rare forms of neurodegenerative disease)
- Impaired blood flow to or in the brain.
other long-term health problems – dementia tends to progress more quickly if the person is living with other conditions, such as heart disease, diabetes or high blood pressure, particularly if these are not well-managed.What is the 30 question test for dementia? ›
The Montreal Cognitive Assessment (MoCA) is a tool that helps healthcare professionals detect mild cognitive impairment and Alzheimer's disease in people. A 2021 study found that it is a better measure of cognitive function than the MMSE. It consists of 30 questions that take 10–12 minutes to accomplish.Can a blood test detect dementia? ›
Blood tests are also used for genetic tests which can reveal, for example, if someone has the defective genes usually present in frontotemporal dementia (Pick's disease) or young onset Alzheimer's.What is the brain key test? ›
The test involves alternately tapping keys at the opposite end of a keyboard using one finger. Subjects perform this as fast and accurately as possible during a 30 s period and this is then repeated with the other hand to derive several scores.How do I test myself for dementia? ›
The Self-Administered Gerocognitive Exam, known as SAGE, is a brief, pen-and-paper cognitive assessment tool designed to detect the early signs of cognitive, memory, or thinking impairments. The test evaluates your thinking abilities.What is the 4 hour test for dementia? ›
This process lasts around four hours and includes a series of in-depth analyses, such as one-on-one interviews and written and oral tests. These assessments are designed to gauge specific cognitive functions, like attention, problem solving, spatial skills, and executive functioning.
Background: The seven minute screen (7MS) is a compilation of the temporal orientation test, enhanced cued recall, clock drawing, and verbal fluency. It has been shown to be useful for detecting Alzheimer's disease in a population of patients with memory complaints.
The current evidence indicates that while chronic stress may play a role in the development or progression of dementia, it does not necessarily cause dementia. Hopefully, further research can begin to uncover what role stress plays in a person's risk of developing dementia.What is one of the first signs of cognitive decline? ›
You find it hard to make decisions, finish a task or follow instructions. You start to have trouble finding your way around places you know well. You begin to have poor judgment. Your family and friends notice any of these changes.What are 3 causes of dementia? ›
Causes of vascular dementia
This can happen as a result of: narrowing and blockage of the small blood vessels inside the brain. a single stroke, where the blood supply to part of the brain is suddenly cut off. lots of "mini strokes" that cause tiny but widespread damage to the brain.
- eating a healthy, balanced diet.
- maintaining a healthy weight.
- exercising regularly.
- keeping alcohol within recommended limits.
- stopping smoking.
- keeping your blood pressure at a healthy level.
More Evidence That Alzheimer's Disease May Be Inherited from Your Mother. Results from a new study contribute to growing evidence that if one of your parents has Alzheimer's disease, the chances of inheriting it from your mother are higher than from your father.What are the 10 early signs of dementia? ›
- Sign 1: Memory loss that affects day-to-day abilities. ...
- Sign 2: Difficulty performing familiar tasks. ...
- Sign 3: Problems with language. ...
- Sign 4: Disorientation to time and place. ...
- Sign 5: Impaired judgment. ...
- Sign 6: Problems with abstract thinking. ...
- Sign 7: Misplacing things.
What are the foods that fight memory loss? Berries, fish, and leafy green vegetables are 3 of the best foods that fight memory loss. There's a mountain of evidence showing they support and protect brain health.What puts you at high risk for dementia? ›
The risk of developing Alzheimer's or vascular dementia appears to be increased by many conditions that damage the heart and blood vessels. These include heart disease, diabetes, stroke, high blood pressure and high cholesterol. Work with your doctor to monitor your heart health and treat any problems that arise.What foods prevent dementia? ›
- Leafy green vegetables, at least 6 servings/week.
- Other vegetables, at least 1 serving/day.
- Berries, at least 2 servings/week.
- Whole grains, at least 3 servings/day.
- Fish, 1 serving/week.
- Poultry, 2 servings/week.
- Beans, 3 servings/week.
- Nuts, 5 servings/week.
Is there a genetic test for dementia? Yes. It is possible to be tested for single-gene changes and some of the risk variants linked to dementia. However, genetic testing for dementia is not always appropriate.
Women have a greater risk of developing dementia during their lifetime. In fact, around twice as many women have Alzheimer's disease – the most common type of dementia – compared to men. The main reason for this greater risk is because women live longer than men and old age is the biggest risk factor for this disease.What are the red flags of dementia? ›
1. Memory loss that disrupts daily life: forgetting events, repeating yourself or relying on more aids to help you remember (like sticky notes or reminders). 2. Challenges in planning or solving problems: having trouble paying bills or cooking recipes you have used for years.