What Are the Types of Dementia? Different Variations You Should Know

If you notice an older loved one suddenly seeming more forgetful than usual, your first thought may be dementia. It’s a reasonable assumption: Around 50 million people worldwide live with dementia, a number projected to increase to 152 million by 2050. Dementia itself is an umbrella term for a particular group of symptoms, which include difficulties with memory, language, problem-solving, and other cognitive skills, according to the Alzheimer’s Association.

That number doesn’t include people living with a possible precursor to dementia: mild cognitive impairment (MCI). These are cognitive changes, such as forgetfulness or losing their train of thought, that are serious enough to be noticed by the individual and their loved ones, but not enough to affect their ability to independently complete daily activities. Up to 18 percent of people aged 60 or over have MCI, and of those, an estimated 10 to15 percent will progress to dementia each year.

There are many different kinds of dementia. Alzheimer’s disease is the most common form—more than 6 million Americans live with Alzheimer’s—but there are other types, too, including vascular dementia, frontotemporal dementia, Lewy body dementia, and Parkinson’s disease dementia. There is also mixed dementia, which is a combination of different disorders, such as Alzheimer’s and vascular dementia, notes Gary Small, MD, Chair of Psychiatry at Hackensack University Medical Center in Hackensack, New Jersey, and a member of TheKey’s Scientific Advisory Board.

If you have a loved one with any form of dementia, it can seem overwhelming. Understanding the type they have, however, can help—especially when it comes to getting them the care they need. Read on to learn about the different types of dementia, who is most at risk, the warning signs, how the disease is treated, and how you can best support your loved one.

Alzheimer’s Disease

Alzheimer’s disease is the most common type of dementia in the U.S., accounting for at least two-thirds of cases in people aged 65 and older.

What’s happening within the brain: Alzheimer’s is characterized by an accumulation of abnormal protein deposits called beta-amyloid and neurofibrillary tau tangles in the areas of the brain that control memory and thinking, explains Dr. Small, co-author of The Memory Bible. The accumulated amyloid deposits clump together and form plaques, which may block brain cell signaling and activate immune system cells that trigger inflammation and devour disabled cells. In addition, tau tangles are twisted strands of a protein that may cause nerve cells to die.

In the early stages of Alzheimer’s—before symptoms can be detected—plaques and tangles begin forming in brain areas involved in learning, memory, and thinking.

Who’s most at risk: Most cases of Alzheimer’s are among older adults, affecting 5 percent of people aged 65 to 74, 13 percent of people aged 75 to 84, and 33 percent of those 85 and older, according to the Alzheimer’s Association. Almost two-thirds of those cases are among women.

Why is Mom or Grandma more at risk? One possible reason: Women tend to live longer than men, and age is the greatest risk factor for Alzheimer’s. Another possible reason: There is research showing that female reproductive hormones may play a role, too.

Other high-risk groups: Older Black and Hispanic adults are up to twice as likely to develop Alzheimer’s. Studies have been unable to pinpoint exactly why; however, researchers speculate that factors relating to racial disparities in healthcare, socioeconomic factors, and an increased risk for chronic conditions associated with a higher likelihood of developing dementia, such as diabetes and cardiovascular disease, may contribute to these observed disparities in cognitive decline.

Symptoms: Alzheimer’s dementia symptoms initially present as problems with short-term memory, says Dr. Small. “There’s a gradual onset and a gradual cognitive decline,” he explains. On average, a person with Alzheimer’s lives four to eight years after diagnosis, although they can live as long as 20 years.

In the early to middle stages of Alzheimer’s, a person may have trouble handling money and paying bills, and may exhibit forgetfulness and mood and personality changes. Symptoms can also include suspiciousness, confusion, problem-solving difficulties, and repetitive questioning or behaviours.

In later stages of Alzheimer’s, symptoms include:

• Increased memory loss and confusion
• Difficulty with language
• Trouble carrying out multistep tasks like getting dressed
• Inability to recognize family and friends
• Impulsive behaviour like undressing in public
• Restlessness and agitation, especially in the late afternoon or evening (often referred to as “sundowning”)

Care: While prescription treatments for Alzheimer’s exist, they only treat symptoms rather than the actual disease, says Dr. Small. These treatments include galantamine, rivastigmine, and donepezil: drugs known as cholinesterase inhibitors, which appear to work by preventing the breakdown of acetylcholine, a brain chemical that plays a crucial role in memory and thinking.

Moderate to severe Alzheimer’s may respond to memantine, a drug that regulates the brain chemical glutamate, and which may help people maintain their regular daily life a little longer. It’s important to work with your loved one’s doctor to find the best medication to fit their needs.

Besides determining the right medication, it’s important for family caregivers to learn how to offer support that isn’t overbearing. “This is especially true with early-stage Alzheimer’s, when people may not yet need help with activities of daily living,” says Shadi Gholizadeh, PhD, MPH, Director of Memory Care at TheKey. “Let your loved one with dementia take the lead and do the activities that matter most to them. This way, they see your role as more of an assistant than a caregiver, which can be less overwhelming.”

Vascular Dementia

This is one of the most common causes of dementia. In fact, about 5 to 10 percent of people with dementia have vascular dementia. However, it more commonly occurs as part of mixed dementia, according to the Alzheimer’s Association.

What’s happening within the brain: “There’s a compromise to the blood vessels that supply oxygen and nutrients to the brain cells,” explains Dr. Small. This is possibly due to a stroke, or mini-stroke, which may have gone unrecognized, he notes.

Reduced blood flow to the brain can damage and even kill brain cells, which is the cause of this particular form of dementia. These brain changes often also occur with other types of dementia, such as Alzheimer’s and dementia with Lewy bodies (more on that below).

Who’s most at risk: Like Alzheimer’s, the older you are, the higher your risk of vascular dementia. But any risk factors linked to cardiovascular disease—such as a high-fat diet, smoking, high blood pressure, or being overweight—can increase your chances of developing vascular dementia, explains Dr. Small. Sleep apnea may also elevate your risk of stroke, which can lead to vascular dementia.

Symptoms: Vascular dementia may cause memory loss symptoms similar to Alzheimer’s, says Dr. Small. Other common signs of vascular dementia include:

• Impaired judgment
• Problems paying attention
• Impaired function in social situations
• Trouble finding the right words
• Changes in personality, like displaying agitation or anger
• Hallucinations

Unlike other forms of dementia, however, certain types of vascular dementia may present with a stepwise declining structure, says Dr. Gholizadeh. “The decline in functioning can at times be steeper compared to other dementias, which tend to have a more gradual, slower progression,” she notes.

Care: As with Alzheimer’s disease, there is no known cure for vascular dementia. Doctors often use the same drugs (memantine and a cholinesterase inhibitor) for both, says Dr. Small. You may also be able to prevent vascular dementia from worsening by treating underlying causes such as high blood pressure, high cholesterol, and Type 2 diabetes.

Proper care at home is also crucial. “Many times, people with vascular dementia can have difficulties following instructions, so it’s important to break down activities into smaller steps,” advises Dr. Gholizadeh.

A person with vascular dementia, for example, may no longer be able to interpret verbal or nonverbal cues. Caregiving advice from the University of California San Francisco Memory and Aging Center suggests: Be clear, concise, and consistent in your communications. For example, repeat instructions with the same words or message. Keep extra noise and distractions to a minimum when you are talking with loved ones, and use names instead of ambiguous pronouns such as he or she. If your loved one experiences delusions or episodes of paranoia, try to note potential triggers, like specific topics or genres of media, so you can try to avoid them when possible.

Frontotemporal Dementia

This is another type of dementia, occurring in approximately 5 to 15 percent of cases.

What’s happening within the brain: In this behavioural variant, higher than normal levels of proteins, such as tau, clog up two important areas of the brain: the frontal and temporal lobes. This may cause nerve cell damage that can lead to behavioural and personality changes such as lack of judgment, loss of inhibition, a disinterest in personal hygiene, as well as difficulty speaking and understanding words.

Who’s most at risk: Unlike other forms of dementia, such as Alzheimer’s, most people with frontotemporal dementia (FTD) are diagnosed at an earlier age, often in their 40s, 50s, or early 60s. FTD can also develop as early as the 20s. About a third of the time, it’s inherited, which is why genetic counseling and testing are available if you have a family history of FTD.

Symptoms: “We don’t see as many memory issues initially. It’s usually trouble with language, like having trouble finding the right word, and personality changes like inappropriate social behaviour and lack of judgment,” says Dr. Small. Because these symptoms are often hard to spot, it can be more challenging to get an accurate diagnosis of dementia.

To help understand how extreme behavioural changes can be, Dr. Small recalls a case of an obstetrician who may have experienced FTD after he started to sign his initials next to patients’ C-section scars. “The obstetrician had intact memory to perform surgery, but his altered personality led to behavioural problems and impaired judgment,” Dr. Small explains.

In advanced FTD stages, people can develop muscle weakness and coordination problems that can make it difficult to swallow, chew, move around, and control their bladder and bowels.

Care: There’s no cure for FTD. Treatment may involve medications such as a type of antidepressant known as a selective serotonin reuptake inhibitor (SSRI) and antipsychotic drugs. “Treatment is very hit or miss: There are no drugs specifically indicated for it,” says Dr. Small.

That’s why behavioural support is so important. “First, it’s important to recognize that the personality and mood changes you may see in your loved one are symptoms of this disease due to damage to specific areas of the brain,” says Dr. Gholizadeh. Second, Dr. Gholizadeh recommends keeping communication simple. “Use the same words as much as possible for consistency, and speak slowly,” she advises. “Keep your tone calm and even, and make your words count.”

It’s also essential to realize that some behaviours, such as physical aggression, may be due to a person’s frustration at not being able to find the words to express how they are feeling. According to the National Institute on Aging, coordinating with a speech-language pathologist to identify communication tools, such as albums with labeled photos of people and objects, may help mitigate frustration.

Dementia with Lewy Bodies

Lewy body dementia (LBD) affects about 1.4 million people in the U.S. and accounts for about 5 percent of all dementia cases in older people.

What’s happening within the brain: Abnormal deposits of a protein called alpha-synuclein (also known as Lewy bodies), affect chemicals and their messengers in the brain for reasons not fully understood. However, it is believed the buildup may be due to mutations in the SNCA and SNCB genes, which provide instructions for making brain proteins that help neurons communicate.

Many people whose brains show deposits of Lewy bodies also show deposits of the plaques and tangles associated with Alzheimer’s disease.

Who’s most at risk: Dementia with Lewy bodies typically occurs at age 50 or over, and appears to affect slightly more men than women. Some research, however, points to a nearly equal gender ratio of those affected.

Symptoms: As with most other forms of dementia, signs of dementia with Lewy bodies are subtle at first and become more pronounced over time. The following early-stage symptoms can be common:

• Movement problems such as changes in handwriting, muscle rigidity or stiffness, a shuffling walk, and loss of coordination
• Detailed visual hallucinations that usually involve people or animals, and which often recur
• Periods of time when the person appears delirious: They may stare into space, appear lethargic or drowsy, and their speech may be garbled.

Care: Your loved one’s doctor may prescribe some of the same medications used for Alzheimer’s. They may also recommend different therapies, such as occupational, speech, and physical therapies.

Since LBD can cause sleep issues—for example, REM sleep behaviour disorder, where a person talks and acts out in their sleep—it’s important to practice good sleep hygiene to ensure your loved one gets more rest, says Dr. Gholizadeh. This may mean limiting naps for some people or aiming to be consistent with bed and wake-up times. Also, encouraging your loved one to stay active can help tire the body, so they sleep more soundly at night.

It’s also important to provide comfort and validation to your loved one, Dr. Gholizadeh adds. “Since visual hallucinations can be common and distressing, you should never argue with a person when they are having one,” she says. Instead try “joining their reality and think about what they are experiencing.” For example, if Mom is afraid to get into bed because she thinks she sees a large snake in the room, rather than arguing with her about the presence of the snake, acting out the process of removing the imaginary reptile may be an effective intervention that helps her feel heard and like you’re on her team.

Parkinson’s Disease Dementia

Up to 80 percent of people living with Parkinson’s disease will go on to develop dementia-like symptoms. The average time from the onset of movement problems to developing dementia is about 10 years. “We know that these patients are at a higher risk to develop both dementia and depression,” notes Dr. Small. Alpha-synuclein, a protein that plays a central role in Parkinson’s, forms Lewy bodies that can disrupt normal brain functioning and lead to dementia.

What’s happening within the brain: The nerve cells in the basal ganglia, an area of the brain that controls movement, become impaired or die. While these brain changes begin in a part of the brain that plays a key role in movement, as more cells become affected, other mental functions may become impaired, including memory, and the ability to pay attention, plan steps required to complete a task, and make sound judgments.

Who’s most at risk: Parkinson’s itself is more common among white populations compared to Asian or Black populations. Men are also more likely to develop the condition.

People with Parkinson’s are likelier to develop dementia if they:

• Are over the age of 60
• Have a greater severity of motor symptoms such as tremors and slowed movement
• Already have mild cognitive impairment, which can be a precursor to dementia
• Experience hallucinations
• Have a feature of Parkinson’s known as postural instability and gait disturbance (PIGD), which means they may “freeze” in mid-step, shuffle, and have problems with balance

Symptoms: If your loved one has Parkinson’s, warning signs of dementia include changes in memory, concentration, and judgment, as well as visual hallucinations, delusions, and sleep disturbances.

Care: Cholinesterase inhibitors, which are used in Alzheimer’s treatment, may help with Parkinson’s dementia symptoms. Your loved one’s doctor might also take them off certain medications used to treat Parkinson’s, such as carbidopa-levodopa, because it can aggravate hallucinations and confusion. It’s also recommended that a person avoid taking antipsychotic drugs, which can worsen Parkinson’s symptoms.

If you’re caring for someone with Parkinson’s disease dementia, it can be particularly challenging because you are dealing with both movement and cognitive challenges, says Dr. Gholizadeh. “You may see what appears to be resistance to care, but is really that they’d like help with a particular task in a different way and aren’t able to express that to you,” she explains.

It can be useful to set a pace for movement activities (such as walking), for example, using a metronome or music to set the pace. It’s also a good idea to declutter and simplify living areas, and use low-level nighttime lighting. This will make it easier for your loved one to move around and reduce confusion.

Rapidly Progressive Dementias

These are dementias that progress quickly, typically within weeks or months. They are exceedingly rare and often difficult to diagnose. One of the more common ones is Creutzfeldt-Jakob disease, which occurs in about one in 1 million people worldwide.

What’s happening within the brain: A specific protein called a prion protein—which is found throughout the body—folds into an abnormal 3D shape in the brain and destroys brain cells.

Who’s most at risk: About 85 percent of the time, sporadic Creutzfeldt-Jakob disease affects people aged 60 to 65. Another form, familial Creutzfeldt-Jakob disease, which accounts for about 10 to 15 percent of cases, develops earlier, with some genetic types appearing between the ages of 20 to 40. The third type, acquired Creutzfeldt-Jakob disease (also sometimes known as mad cow disease), results from exposure to an outside source of abnormal prion protein, such as being acquired through infected meat products.

Symptoms: Rapidly Progressive Dementias (RPDs) have similar symptoms to other forms of dementia, including problems with the ability to speak and understand, difficulty controlling movements, mood changes, and trouble thinking.

Care: Since there is no cure for many cases of RPD, care focuses on treating symptoms and supporting patients and their families. It can be particularly jarring for relatives to see their loved one rapidly lose their ability to move or speak and suddenly require full-time care. “For people living with rare conditions and their families, the experience can be even more isolating because there is less information out there and fewer resources,” notes Dr. Gholizadeh. “Family members may need more support as they go through a period of acute grief, too.”

Regardless of what type of dementia your loved one has, it’s important to realize that dementia itself is unpredictable. “Knowing the type is helpful because it can guide treatment and help families prepare for common care challenges,” says Dr. Gholizadeh. “But what ultimately matters most are the specific symptoms and needs of each particular person.” That’s why TheKey focuses on person-centered care, she adds. “We recognize that symptoms can change constantly, and the foundation of our dementia care is to be flexible. It helps us recognize the humanity and individuality of each person with dementia.”

6 Most Common Types of Dementia

Source: Alzheimer’s Association