To have a diagnosis of dementia, the decline in function must impact a person's ability to perform everyday activities.
Researchers looking at data from 2000 to 2012 found that around 8.8 percent of people aged 65 years and older in the United States had a form of dementia.
In this article, we look at several types of dementia and how they change as the condition progresses.
Dementia develops in various stages.
Symptoms of dementia tend to get worse over time.
The rate of progression varies between people. Genetics, age, and overall health, as well as the underlying cause of the dementia might play a role in how fast the disease progresses.
Dementia has distinct stages that shape treatment and impact on health in different ways. It should be noted that scientists have devised different systems of staging for a variety of dementia types, including dementia that occurs with Alzheimer's disease.
No staging system is perfect, and the stages often overlap. Symptoms may appear at certain stages, then resolve, while other health effects progressively get worse.
Dementia often, but not always, starts with a mild decline in the ability to think. For example, a person may forget a recent conversation or the name of a familiar object.
Keep in mind that everyone has moments in which something gets stuck on the tip of their tongue.
Dementia goes beyond this. Moments such as these happen with increased frequency, though they may not initially reduce the quality of life or a person's ability to function on a day-to-day basis.
Early symptoms may also include a decreased ability to perform certain tasks, such as paying bills or following a recipe. People close to an individual with dementia may also notice subtle changes in personality.
At this stage, a person with dementia may start to realize that something is not right but may choose to hide their symptoms.
Some types of dementia may affect language, while others affect memory or movement. It is easiest to distinguish the types in their early stages.
Moderate dementia symptoms
As dementia progresses, symptoms become harder to hide. More noticeable symptoms may develop. Help with self-care or everyday activities may be necessary.
Personality changes may become more noticeable. The person may experience paranoia, confusion, or fear, and memory loss may increase.
People with moderate dementia commonly forget their address or other personal information, including their phone number.
Sleep patterns and moods may also change.
Late-stage or severe dementia symptoms
Gradually, dementia can progress and become severe. At this stage, it often significantly impairs a person's memory. A person with severe dementia may not recognize family members.
Symptoms of late-stage dementia may include an inability to communicate, walk, and control bowel and bladder function.
Severe dementia can also cause muscle rigidity and abnormal reflexes. A person will usually need full-time personal care for eating, bathing, and dressing.
People with severe dementia are vulnerable to infections, including pneumonia, and they be unable to move in bed. In this case, bedsores are a risk.
Knowing the stages of dementia can help a person plan, but everyone with dementia has a unique experience. It is important to make the necessary lifestyle adaptations while remaining flexible about meeting needs as they evolve.
Treatment options over time
Medicines can help manage dementia symptoms.
Currently, no cure is available for dementia. However, treatments can help reduce symptoms and manage behavioral changes.
The right treatment may change over time. A doctor may prescribe different classifications of medication as the disease progresses.
Medications can reduce symptoms by adjusting chemicals that carry messages to the brain cells.
These drugs are called cholinesterase inhibitors. Doctors often prescribe them for people with mild to moderate symptoms. Cholinesterase inhibitors treat symptoms associated with confusion, communication, and memory.
In people with moderate to severe dementia, treatment may also include memantine. Memantine is a drug that may help improve language, thinking, and memory functions.
Memantine works by regulating glutamate, a chemical in the brain that supports memory and learning. Memantine may delay the progression of dementia symptoms temporarily in some people.
Treatment options may also include medications that reduce behavioral and psychological changes, such as anxiety and sleep problems.
In later stages, doctors may recommend particular drugs to treat specific symptoms, such as fear, restlessness, and hallucinations.
As dementia progresses, treatment may also focus on improving the quality of life. For example, occupational therapy can help teach people with dementia how to use adaptive equipment or improve fine motor skills.
Types of dementia
Dementia has a variety of causes, and different types of dementia cause different changes in the brain. Each type also progresses in a different way.
Common types of dementia include Alzheimer's disease, vascular dementia, dementia with Lewy bodies, and mixed dementia.
The most common cause of dementia is Alzheimer's disease. According to the Alzheimer's Association, the disease is responsible for between 60 and 80 percent of dementia cases.
The causes of Alzheimer's are not entirely clear, but healthcare professionals find clumps of a protein called beta-amyloid in the brains of people with this disease.
Alzheimer's often develops gradually and may be the slowest of all types to progress.
This type causes difficulties in planning and making decisions, slow or sluggish thought, and problems concentrating, with brief episodes of confusion.
There are two subtypes of vascular dementia, and they progress in different ways.
Subcortical dementia progresses at a pace similar to Alzheimer's, while stroke-related dementia develops more suddenly. Symptoms are consistent, then grow rapidly more severe, before becoming stable again.
Dementia with Lewy bodies
Lewy bodies are deposits of protein that develop throughout the brain, including in the cerebral cortex, which oversees language and thinking. They damage and kill nerves in the brain over time.
In the early stages of dementia with Lewy bodies, alertness and attentiveness may vary wildly from day to day or even throughout the same day.
People with this type of dementia may hallucinate, and they often feel persecuted as a result.
The symptoms may start to resemble Alzheimer's as this type of dementia progresses, with episodes of memory loss, shouting, and confrontational behavior. These symptoms can be especially challenging for caregivers.
Mixed dementia involves more than one cause. There may be damage to blood vessels and harmful deposits of protein in the brain, for example.
The overlap in types and stages can make it more difficult to predict how symptoms present and develop.
Dementia has a complicated, multifaceted set of symptoms, and caregivers should focus on providing a reactive support network.
Diagnosis and outcome
A CT or PET scan can show the protein deposits that are characteristic of dementia.
No single test can determine whether a person has dementia.
Tests will evaluate:
- thinking ability
- neurological function
- movement and balance
- visual perception
A medical history and blood tests can help rule out other possible causes of dementia symptoms.
Imaging studies, such as a CT or PET scan, can identify specific protein deposits in the brain or a disrupted blood supply.
Dementia scales can help determine if dementia is present and how far it has progressed. The Global Deterioration Scale can be useful in determining the severity of overall dementia.
Doctors use a range of scales to assess dementia stages. The tests measure the severity of symptoms and the ability to carry out daily functions.
A common test is the mini-mental state examination, which people sometimes shorten to MMSE. It gives information about a variety of areas of cognition, such as orientation, registration, recall, language, and praxis.
Stages range from 1 to 7, in which stage 7 is the most severe. A doctor will conduct a combination of tests to make an assessment.
The outlook for people with dementia varies. Age at diagnosis and response to treatment are two factors that affect how the condition progresses.
Living with dementia in the later stages
A person with dementia may wish to have input in decisions about care before they become unable to communicate their wishes.
This advanced care planning provides the opportunity for a person with dementia to state what they want and do not want, such as living in a nursing home or receiving care at home.
Living with late-stage dementia can often be challenging for individuals and their caregivers. As symptoms progress, more care becomes necessary.
Strategies that may help include techniques to trigger memory, such as visual clues, music, and notes.
Assistive technology devices are also available, such as communications aids, automatic shutoff devices, and computerized recall devices.
Caregivers should create an environment that is calm and safe. It is crucial to identify and correct safety concerns, for example by removing tripping hazards and otherwise making sure that rooms are easy to navigate.
Caregivers should also ensure that the individual follows their medication regimen and receives enough nutrition.
Late-stage dementia can also be a difficult time for caregivers. It is important to have a strong support system and allow time to recharge.
What is the most severe form of dementia?
Regardless of the type of dementia, they can all be quite severe and disrupt the lives of those involved.
Dementia involves not only the person with the diagnosis but also those close to the person, such as their spouse or children. A diagnosis of dementia is often life-changing for the family unit.
From a practical perspective, I would say the most severe form of dementia is one in which the individual has limited-to-no resources and a minimal or nonexistent support system.Timothy J. Legg, PhD, CRNP Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.