There isn’t one or two forms of dementia, but several, and they are confusing to everyone.

The number of people affected by dementia is staggering and growing rapidly. Currently, 7.2 million Americans aged 65 and older have Alzheimer’s disease, projected to reach 13 million by 2050. Over 1 million Americans have Lewy body dementia.

Women are disproportionately affected, making up about two-thirds of Alzheimer’s patients, partly because they tend to live longer than men. African Americans are twice as likely to develop dementia compared to whites, while Hispanics are 1.5 times more likely. The lifetime risk of developing dementia after age 55 is estimated at 42 percent for all Americans, which is much higher than previously thought.

And the economic impact is enormous, with health and long-term care costs for people with dementia projected to reach $384 billion in 2025 and nearly $1 trillion by 2050. Dementia's impact is vast, affecting millions with high costs ($413 billion, including 19 billion hours of unpaid care in 2024) and widespread misunderstanding of its types and treatments. One important aspect of this care is that provided by caregivers in families, who can suffer with high rates of burnout.

Dementia as a brain condition isn’t just one disease — it’s actually a group of related illnesses that all cause problems with memory, thinking, and daily activities. Currently, over 57 million people worldwide live with dementia, and this number is expected to nearly double every 20 years. While dementia mainly affects older people, not everyone will develop it as they age. For mental health professionals, patients, and their families alike, the many forms of dementia present challenges.

in essence, dementia describes a collection of symptoms that occur when diseases damage the brain. Think of it as an umbrella term covering several conditions. The symptoms worsen over time, interfering with a person’s ability to work, maintain relationships, and care for themselves. Understanding the different types of dementia is crucial because each one affects the brain in a unique way and may necessitate distinct approaches to treatment and care. In fact, some people are diagnosed with dementia when it is a dietary disorder, not a brain deterioration disorder.

Alzheimer’s disease is by far the most common form of dementia, causing about 60 to 70 percent of all cases. This disease occurs when two harmful proteins accumulate in the brain: amyloid plaques and tau tangles. These proteins interfere with brain cell communication and ultimately lead to the death of brain cells.

Brain shrinkage and cell death are visible on scans, with memory loss (especially of new information) appearing first. As the disease progresses, people have difficulty with language, decision-making, recognizing family members, and eventually with Activities of Daily Living (ADLs). At this stage, it is not unusual to see someone who does not know how to button a shirt.

Additionally, as I have observed in Alzheimer’s research protocols, the patient may not know how to place a letter into an envelope. One woman did not recognize what a fork was used for, what was food, nor how to eat at a table.

Vascular dementia is the second most common type, accounting for about 18 percent of dementia cases. Blood flow to the brain is reduced, often after strokes or due to damaged blood vessels from conditions like high blood pressure or diabetes. Unlike Alzheimer’s, which typically starts with memory problems, vascular dementia often begins with difficulties in planning, organizing, and making decisions.

People may experience sudden periods of confusion or difficulty concentrating. The symptoms can come on suddenly after a stroke or develop gradually over time as blood vessels become more damaged. Also accompanying most strokes is a period of severe depression.

Lewy body dementia affects about 26 percent of people with dementia, though it often occurs alongside other types. More than 1 million Americans have this condition, caused by protein clumps that form inside brain cells. What makes this type unique is its fluctuating symptoms — people might seem alert and clear-thinking one day, then confused and drowsy the next. This fluctuation of symptoms can make it confusing as symptoms are also caused by hypertension.

Visual hallucinations are common, where people see things that aren’t there, like animals or people in their room. Sleep problems are typical, with people often acting out their dreams physically. Movement difficulties similar to those associated with Parkinson’s disease, such as slow walking, stiffness, and tremors, are also common signs. Some research has indicated a relationship between genetics, Alzheimer’s, Parkinson’s, and Lewy body dementia.

Frontotemporal dementia (the actor Bruce Willis has this diagnosis) accounts for about 5 percent of dementia cases and often strikes people younger than other types, sometimes affecting people in their 40s and 50s. This disease affects the front and sides of the brain, which control personality, behavior, and language.

Instead of memory problems appearing first, people with frontotemporal dementia often experience dramatic personality changes. They might become unusually aggressive, lose social inhibitions, say inappropriate things, or develop strange eating habits. Some people lose their ability to speak or understand language, while their memory might remain relatively intact for years.

Types of Dementia Are Challenging

Distinguishing between types of dementia can be challenging because symptoms often overlap, but doctors use several methods to make accurate diagnoses. They look at symptom patterns — memory problems usually indicate Alzheimer’s, while personality changes suggest frontotemporal dementia, and fluctuating awareness points to Lewy body dementia.

Advanced brain scans can show characteristic patterns of brain shrinkage or protein deposits specific to each type. New blood tests and spinal fluid tests can detect specific proteins associated with different types of dementia. Information about how symptoms developed and the person’s medical history also helps doctors identify the likely cause. Often, this is the responsibility of a family member.

There is another type of dementia that can also deceive healthcare professionals, and that is Creutzfeldt-Jakob. I know of one instance where a research facility went to collect Alzheimer’s brains. Once the brains were delivered to the facility, they were alerted to the fact that the brains were infected with Creutzfeldt-Jakob. This is a highly contagious dementia. Any surgical instruments that may have been used on a patient with this disease must be destroyed to prevent contamination of other patients.

Unfortunately, there’s still no cure for any form of dementia, but several treatments can help manage symptoms and potentially slow progression. For Alzheimer’s disease, the FDA has approved several medications that work in different ways. Traditional treatments approved by the FDA help maintain thinking abilities by preserving brain chemicals (whenever you see a word ending in -erase, it’s an inhibitor) needed for memory and learning.

For some forms of dementia, treatment mainly focuses on managing specific symptoms. People with Lewy body dementia might receive medications for movement problems or hallucinations, though doctors must be careful because some psychiatric medications can make symptoms worse. Vascular dementia treatment emphasizes controlling risk factors like high blood pressure, diabetes, and high cholesterol to prevent further damage to blood vessels in the brain.

Hope for the Future

Despite these sobering statistics, the future of dementia research offers genuine hope. The research pipeline includes over 125 potential treatments currently being tested, representing an unprecedented level of scientific activity. Researchers have found that people taking diabetes drugs like semaglutide had a reduced risk of developing dementia, leading to trials specifically for brain protection.

Other promising candidates include a second-generation immunotherapy drug that targets amyloid more effectively than current treatments, as well as an antibody that activates brain immune cells to more effectively clear harmful proteins. Scientists are also exploring treatments that target multiple aspects of dementia simultaneously, including reducing inflammation, improving blood flow to the brain, and protecting brain cells from damage. Inflammation appears to be an important aspect in dementia as well as depression.

Artificial intelligence is revolutionizing drug discovery, enabling researchers to identify promising compounds more quickly and design more effective clinical trials. Lifestyle changes are also important. Prevention strategies are being studied intensively, with evidence suggesting that managing risk factors like diabetes, high blood pressure, depression, and social isolation could prevent or delay dementia onset. New blood tests and brain scans can detect dementia-related changes decades before symptoms appear, allowing for earlier intervention when treatments are most effective.

While dementia remains a formidable challenge, the landscape is transforming. The approval of the first drugs that can actually slow Alzheimer’s progression marks a turning point in the field. Although these treatments aren’t cures and have limitations, they demonstrate that modifying the disease course is possible.

For families dealing with dementia, understanding the different types of dementia helps in obtaining the correct diagnosis and treatment. Early detection is becoming increasingly important as new treatments work best when started early. With unprecedented investment in research, there’s genuine reason for hope that more effective treatments — and eventually cures — will emerge in the coming years.