4 Main Types of Dementia: What’s the Difference?
More than 55 million people around the world live with dementia, with close to 10 million new cases diagnosed each year. The syndrome ranks 7th among the leading causes of death due to disease. From those that have it to loving caregivers, the 4 main types of dementia impart heavy physical, mental, emotional, social and financial tolls.
Keep reading to find out more about these different types of dementia, ways to lower your risk of them and how to slow down their progress.
What Is Dementia?
Dementia is not a disease but a syndrome. These are a group of dementia signs and symptoms along with physical findings that often occur together and for which direct causes aren’t fully known.
The 4 main types of dementia impair the way your brain functions (i.e., your cognitive or mental functions), oftentimes slowly and progressively.
Who’s at Risk for Dementia?
Is dementia a normal part of aging? It isn’t. But most people with the different types of dementia are older than 65 and the risk rises greatly with each decade beyond this age.
These can also up your risk or cause 1 or more of the 4 types of dementia:
- Family (e.g., parent or sibling) history
- Certain health conditions and lifestyle behaviors such as heart disease, type 2 diabetes, high blood pressure, high cholesterol and smoking nicotine
- Reversible causes such as heavy and prolonged use of alcohol, heavy metal toxins (such as lead and mercury), removable brain tumors, Lyme disease, multiple sclerosis, vitamin B12, thiamin or niacin deficiency and side effects of medicines to treat anxiety, colds and flu, insomnia and depression
4 Main Types of Dementia Stages and Symptoms
Mental functions tend to deteriorate over a few years to a decade or more. But this differs for each person and often depends on which type of dementia you have.
Early Dementia
Early symptoms of the 4 main types of dementia can be subtle and easily missed. You may find it harder to:
- Complete your daily tasks
- Comprehend some aspects of language
- Find and use the right words
- Focus clearly and think abstractly
- Navigate through congested areas, even in familiar places
- Perform more complex tasks
- Reason and use good judgment
- Remember recent events
Moderate Dementia
At this point, you may find you just can’t:
- Control your behavior
- Keep track of time
- Know where you are most of the time
- Learn and recall new concepts
- Name and recognize objects you once knew (called anomia)
- Perform basic self-care tasks (e.g., bathing, dressing, eating and toileting)
- Recognize certain people
- Recall large chunks of information from your past
- Understand much of what you see and hear
You get lost more often, even in your home. And some of your traits become pronounced. For instance, concerns (e.g., money) become obsessions.
You may also come across as:
- Angry
- Anxious
- Apathetic
- Indecisive
- Inflexible
- Irritable
- Passive
- Self-centered
- Withdrawn
You may struggle with insomnia and restless sleep during bedtime hours. This can cause you to feel groggy and drowsy or excessively sleepy and lead to oversleeping during wakeful hours.
Severe Dementia
Late-stage dementia symptoms involve losing almost all mental functions and muscle control. Hallucinations and delusions are also common symptoms.
Once you reach the advanced stages of the 4 main types of dementia, you likely can’t:
- Control bladder or bowel functions
- Eat or drink without choking or aspirating (inhaling bits of food, liquids or mouth secretions into your lungs)
- Perform any self-care measures
- Recognize your face or that of family members or friends (called prosopagnosia)
- Recall any memories
- Talk or articulate words normally (called dysarthria)
- Use or understand language (called aphasia)
- Walk, move or get out of bed without help
What Are the 4 Main Types of Dementia?
The 4 main types of dementia include:
Alzheimer’s Disease
You may wonder, “Is Alzheimer’s a type of dementia?” It’s the most common type of dementia, accounting for upwards of 60% to 80% of all cases.
With Alzheimer’s, you slowly lose cognitive abilities. Parts of your brain degenerate. This destroys nerve cells and the ones that remain respond less to neurotransmitters.
These are chemical messengers that transmit signals between nerve cells in your brain. In particular, your acetylcholine levels drop.
Acetylcholine helps you concentrate, learn and forge memories. This type of dementia often impacts recent memory much more than other mental functions.
Your brain forms:
- Abnormal protein deposits (plaques) called beta-amyloid
- Clumps of dead nerve cells around a beta-amyloid core called senile or neuritic plaques
- Twisted and disorganized strands of protein fibers in your nerve cells called neurofibrillary tangles
- Higher levels of an abnormal protein called tau — a component of beta-amyloid and neurofibrillary tangles
- Abnormal proteins called Lewy bodies, although the other formations are more common
Vascular Dementia
This is the second most common type of dementia in older adults. It often occurs as a mixed dementia type, meaning it occurs alongside Alzheimer’s disease.
Having a major stroke [or many small ones] ups your risk of vascular dementia. Strokes block the blood supply to parts of your brain, causing an infarct (death of affected brain tissue).
Health conditions and behaviors that impair blood flow can damage parts of your brain and raise your risk for stroke and this dementia type. These include smoking along with:
- Atherosclerosis
- Atrial fibrillation (quivering abnormal heart rhythm that can cause blood clots to travel from your heart to your brain)
- Diabetes
- High blood pressure
- High cholesterol
- Thrombolia (excessive blood clotting)
Vascular dementia symptoms tend to progress stepwise up and down. They suddenly get worse, and then plateau or get better to some degree. If another stroke happens, they worsen again.
Dementia With Lewy Bodies
This ranks third among the 4 main types of dementia. Lewy bodies destroy your nerve cells.
These proteins form throughout your brain’s outer layer (i.e., gray matter and cerebral cortex). Your cerebral cortex controls thinking and perception and your ability to use and comprehend language.
Dementia with Lewy bodies can cause:
- Dramatic shifts in alertness and mental function
- Issues with planning, problem-solving, doing complex tasks, copying or drawing and using good judgment
- Psychotic symptoms such as [detailed and often threatening] hallucinations and [complex and bizarre] delusions
- Symptoms seen with Parkinson’s disease such as stiff muscles, shuffling steps, balance issues, tremors and stooped posture
- Sleep problems such as rapid eye movement sleep behavior disorder, causing you to physically act out your dreams while sleeping
- Fainting and problems urinating, having a bowel movement or regulating body temperature (which can cause excess sweating or not enough) due to a haywire autonomic nervous system.
Frontotemporal Dementia
Around half of all frontotemporal dementias are inherited. The telltale symptoms of the 4 main types of dementia show up with this type, too. But dementia symptoms often show up before you’re 65. And you can usually carry out daily tasks and stay aware of the time, date and place.
With this type of dementia, your brain cells house abnormal amounts of tau. It causes loss of nerve cells due to atrophy (shrinking) of your brain’s frontal and temporal lobes.
These areas of your brain help control behavior and personality. As such, disruptive behaviors and personality shifts may ensue.
You may speak rudely to others and display compulsive behaviors such as walking to the same place every day, picking up and manipulating random objects or placing items in your mouth.
Your impulse control and inhibitions may also go by the wayside, which can amplify your interest in sex and tendency to overeat. You’re also more likely to neglect your personal hygiene and have problems with aphasia, dysarthria, anomia and prosopagnosia.
How to Diagnose Dementia
To diagnose dementia, your doctor starts with a:
- Medical history
- Physical exam
- Memory and other cognitive tests to gauge your mental status
Your doctor may then order:
- Blood tests, including a check of your thyroid hormone and vitamin B12 levels
- Brain scan such as computed tomography (CT) or magnetic resonance imaging (MRI) to check for abnormalities that cause dementia
- Positron emission tomography (PET) or single-photon emission CT (SPECT) to identify which of the 4 main types of dementia you have
Can Dementia Be Prevented?
There’s no surefire way to prevent it. But you can lower your risk of the 4 main types of dementia and help extend your lifespan with lifestyle strategies.
Aim to:
- Follow a wholesome eating plan, especially one that supports a healthy weight (e.g., Mayo Clinic diet) and your heart and blood vessel health (e.g., Mediterranean-DASH Intervention for Neurodegenerative Delay [MIND] diet)
- Get at least 30 minutes of brisk exercise 5 or more days a week
- Keep your blood pressure, blood sugar and cholesterol levels in check
- Quit smoking or never start
- Interact with others often and stay socially active
- Stimulate your mind (e.g., play a musical instrument, work on puzzles or play games that challenge your brain)
How Are the 4 Main Types of Dementia Treated?
There’s no cure for most types of dementia, although vascular dementia can be stopped or reversed once the underlying cause or illness is treated. The care plan includes:
Measures to Keep You Safe and Oriented
Nurses or occupational and physical therapists can visit your home and recommend changes to help you stay safe, oriented and stimulated. They can also assess how well you function in certain sticky situations such as driving or making meals.
Your health care team recommends strategies to maintain:
- Structure to help you feel more secure and oriented. Changes to your daily routine, caregivers and surroundings must be explained beforehand using clear and simple terms.
- Scheduled activities that help you feel productive, independent and less anxious, depressed or stressed. These often include simple activities that you once enjoyed or kept your interest prior to having dementia.
- Proper amounts of stimulation. Hobbies and interests can help keep you engaged with life and your mind alert. But these must be kept simple or broken down into small actions to help keep you from getting overwhelmed and more confused by too much stimulation.
Medicines to Support Mental Function
These medicines may improve mental function for a period of time. They include:
- Cholinesterase inhibitors (e.g., donepezil, galantamine, rivastigmine) can help with Alzheimer’s and dementia with Lewy bodies. These help your nerve cells communicate better by blocking an enzyme that breaks down acetylcholine called acetylcholinesterase.
- Memantine to help with moderate to severe dementia and slow the loss of your mental functions. It blocks receptors in your brain that bind to a chemical [thought to damage brain cells] called glutamate.
Medicines for Disruptive Behavior
If measures to support safety and curb disruptive behavior don’t help, these medicines may be considered:
- Antipsychotic drugs for advanced dementia with psychotic behavior. These medicines help with agitation and outbursts but work best for delusions, hallucinations and paranoia.
- Antiseizure drugs may also help with violent outbursts.
Medicines to Treat Other Symptoms of Dementia
Antidepressants can help with depression. And a short course of sedatives may be prescribed to help relieve anxiety.
Resource Links:
- “Adherence to MIND Diet, Genetic Susceptibility, and Incident Dementia in Three US Cohorts” via Nutrients
- “Alcohol and Dementia” via Alzheimer’s Society
- “Alzheimer Disease” via Merck Manual
- “Alzheimer’s Disease Facts and Figures” via Alzheimer’s Association
- “Association of Cardiovascular Health With the Risk of Dementia in Older Adults” via Scientific Reports
- “Behavioral and Psychological Symptoms in Dementia” via StatPearls [Internet]
- “Can Dementia Be Prevented?” via National Health Service
- “Complementary and Integrative Medicine for Neurocognitive Disorders and Caregiver Health” via Current Psychiatry Reports
- “Healthy Lifestyle and Life Expectancy With and Without Alzheimer’s Dementia: Population Based Cohort Study” via British Medical Journal
- “Dementia” via Cleveland Clinic
- “Dementia” via World Health Organization
- “Dietary Patterns in Middle Age: Effects on Concurrent Neurocognition and Risk of Age-Related Cognitive Decline” via Nutrition Reviews
- “Shared Risk Factors Between Dementia and Atherosclerotic Cardiovascular Disease” via International Journal of Molecular Sciences
- “What Is Dementia?” via Alzheimer’s Association
- “What Is Dementia?” via Centers for Disease Control and Prevention
