Types Of Dementia And Their Symptoms

Dementia may stem from a variety of different causes. Often, each cause of dementia is referred to as a type of dementia. We explore the various types of dementia, along with symptoms and treatment options.

Dementia types

Experts have identified many different potential causes of dementia. Dementia risk increases in adults over age 65, but some types can also occur in adults as young as 30.

Dementia stems from different physiological causes that can lead to both physical and mental decline. Dementia can be considered mild, moderate, or severe, depending on how much it impacts daily living. Some types of dementia can be reversed, while progressive dementias lead to cognitive decline over several years and are ultimately fatal. The following list includes the most common types of dementia.

• Alzheimer's disease

• Vascular dementia

• Frontotemporal lobe dementia

• Lewy body dementia

• Parkinson's disease dementia

• HIV or AIDS-related dementia

• Mixed dementia

• Young-onset dementia

Though there is no way to prevent dementia, the Alzheimer’s Association suggests eating a healthy diet, regular exercise, social connectivity, and intellectual stimulation as a few ways you can reduce the risk of developing dementia. 

Alzheimer's disease

The most common type of dementia is Alzheimer's disease, with 1 of 9 U.S. adults over 65 years of age having the disorder. Most people who develop symptoms of Alzheimer’s are over 65, however, early-onset dementia before age 65 occurs in a small percentage of people who have Alzheimer’s disease. 

Causes

Alzheimer's disease is caused by brain changes. Specifically, the brain develops abnormal clumps, called amyloid plaques, and tangles of fiber, called tau tangles. While genes seem to play a role in the development of Alzheimer's, experts still aren't certain about its exact cause. Certain patient populations may be at higher risk. For example, estimates suggest that 50% or more of people with Down syndrome may develop dementia due to Alzheimer’s as they age.

Symptoms

The earliest symptom of Alzheimer's is usually an issue with learning or memory. For example, a person might learn new information, then quickly forget it. Over time, they may struggle to remember which word they want to say or have trouble with thinking skills associated with everyday tasks, like cooking dinner or paying bills. Symptoms depend on the severity of the disease’s progression.

As Alzheimer’s disease progresses, they may repeat the same questions frequently, lose their belongings or put them in strange places, or become lost easily. In severe cases, Alzheimer's can affect a person's mood or personality, resulting in them acting angry, paranoid, or even violent. Eventually, symptoms like memory loss and motor function impairment interfere too much with daily life for people with Alzheimer’s to live alone. Alzheimer’s can also have physical symptoms. Dementia can cause bladder control issues and lead to accidents; and severe atrophy can affect the spinal cord and affect a person’s ability to move. 

Vascular dementia

Vascular dementia is a blood vessel disease. In vascular dementia, a person experiences dementia symptoms as the result of changes to blood vessels in the brain. 

Causes

Anything that affects blood vessels can lead to vascular dementia. For example, strokes, high blood pressure, diabetes, and atrial fibrillation are all risk factors for vascular dementia.

Multi-infarct dementia refers to when a person develops dementia after multiple small strokes. Subcortical dementia occurs when dementia occurs after the small blood vessels and nerve fibers in the brain's white matter are damaged.

Symptoms

People with vascular dementia experience symptoms similar to other dementia diseases, like trouble learning information or following instructions, poor judgment, forgetting things, misplacing items, getting lost, and struggling to find the right words to say.

When vascular dementia begins after a stroke, the first symptoms will be stroke symptoms. Signs of a stroke can include numbness or weakness in the face, arm, or leg, confusion or trouble speaking, trouble seeing, trouble walking or dizziness, or a sudden, severe headache. 

Frontotemporal lobe (FTD)

Frontotemporal lobe dementia (FTD) involves degeneration of the frontal and temporal lobes of the brain. It used to be called Pick's disease. Frontotemporal lobe dementia is the third leading cause of dementia in adults over 65, and the second leading cause in adults younger than 65.

Causes

In 40% of people with frontotemporal lobe dementia, genetics appear to be the cause. Having a head injury or thyroid disease also increases a person's risk of developing this type of dementia.

Symptoms

Frontotemporal lobe dementia is categorized into three types, and each presents with its own set of symptoms.

• Behavior variant type frontotemporal dementia (bvFTD): This is the most common type of FTD. People who have it may experience personality and behavior changes earlier on than is usual with dementia. They may have fewer memory problems, but experience a lack of emotion and changes in diet.

• Semantic variant frontotemporal dementia: In this type, people commonly struggle to find the words they want to say. They may also have trouble remembering the meaning of words they hear and struggle to recognize familiar faces or objects. Their memory might not be affected until later on.

• Non-fluent variant primary progressive aphasia (nfvPPA): This type of frontotemporal dementia first affects speech, and a person who has it may jumble their words or pause often when talking. They might struggle to speak complex sentences and remember names of things.

Lewy body

In Lewy body dementia, abnormal deposits of alpha-synuclein proteins build up in regions of the brain responsible for the control of thinking, behavior, and movement.

Causes

Experts aren't certain about the causes of Lewy body dementia, but it seems that there are risk factors. Having a family member with the disease or other specific health conditions, like Parkinson's disease or REM sleep behavior disorder, makes it more likely. When caused by Parkinson's, dementia with Lewy bodies may be also called Parkinson's dementia.

Symptoms

This type of dementia is more likely to cause hallucinations early on compared to other types. It can cause visual hallucinations, as well as hearing or smelling things that aren't there. Lewy body dementia may also cause attention problems and trouble staying awake throughout the day. Other symptoms of dementia with Lewy bodies, such as memory loss, might not appear until later, as the disease progresses.

Reversible Dementia

Reversible dementia is a disorder that causes dementia symptoms, but can be cured with treatment. 

Causes

Reversible dementia may stem from one of many causes:

• Depression

• Medication side effects or interactions

• Poor nutrition

• Heart disease

• Lung disease

• Thyroid or other hormone diseases

• Infections, especially syphilis or lyme disease

• Recreational drug use

• Too much alcohol

Symptoms

When a person's dementia stems from one of the above causes, they first experience any symptoms of the cause, such as depression. With time, they develop dementia symptoms, like memory problems.

Other types of dementia

There are many other, rarer types of dementia. We cover a few of them here.

Huntington’s Disease

Huntington’s disease is a rare brain disorder that causes nerve cells in the brain to break down. It usually leads to movement, cognitive, and psychiatric disorders. Symptoms of the condition, including dementia-like symptoms typically present when people are in their 30s or 40s. Laboratory tests like genetic testing, MRI, or CT scans may be used to confirm a diagnosis following evaluation by a doctor. 

Creutzfeldt-Jakob disease

One of the least common forms of dementia, Creutzfeldt-Jakob disease can cause severe impairment in motor and cognitive function, along with sleep disruptions, mental health challenges, and perceptual changes. People with dementia caused by Creutzfeldt-Jakob disease can also experience loss of vision, muscle weakness, and coma as the disorder progresses.  

HIV- or AIDS-related

People who have HIV and AIDS may develop AIDS-related dementia as the disease progresses. Other names for this disorder include AIDS dementia complex (ADC), HIV-associated dementia, and HIV/AIDS encephalopathy. A similar, but more mild disorder is called HIV-associated neurocognitive disorder (HAND). Symptoms include problems with memory, focus, planning, and decision-making.

Chronic traumatic encephalopathy

Chronic traumatic encephalopathy (CTE) is a type of brain disorder that causes dementia symptoms. It's often found in professional football players, boxers, other athletes, military members, and others who suffer repeated blows to the head. This condition was called dementia pugilistica when it was discovered among boxers in the early 1900s. CTE is the preferred name for it now.

Symptoms include memory problems, impulsive or erratic behavior, balance problems, problems with judgment, aggression, and depression. These symptoms come on slowly, but CTE can't yet be diagnosed with certainty until an autopsy is performed after death.

Mixed Dementia

Mixed dementia is a combination of two or more types of changes in the brain that cause dementia. One common example is a person who has both Alzheimer's disease and vascular dementia. Alzheimer's and Lewy body dementia often occur together, too. Because there's so much overlap of symptoms, mixed dementia can be challenging to diagnose, and certainty about the diagnoses may only happen after an autopsy is performed.

Help for you or a loved one while dealing with dementia

Coping with the possibility that you or a loved one might have dementia can add to the normal pressure of every day life. People often fear what will happen as their brain or the brain of their loved one continues to deteriorate. Supportive mental health care can help you work through the emotional challenges associated with a friend or family member’s dementia. One of the best things you can do to address your fear is to talk to a counselor about dementia. They can help you better understand what dementia is and how it might affect you. They can also help you cope with the difficulty of getting a diagnosis, face the impact of the disease, and offer guidance to live a healthy lifestyle.

Online therapy has many benefits that may make it more convenient than in-person sessions. With online therapy, you’re matched with a qualified mental health counselor so you can start treatment right away, no matter where you live. You can attend sessions from the comfort of your home and reach out to your therapist via in-app messaging any time, and they’ll get back to you as soon as they are able.

Online therapy is effective, too. For example, one study found that engaging in online therapy improved the moods and mental health of caregivers for people with dementia. Caring for someone with dementia can take its toll on a person, so receiving help and support is important for caregivers, too.