Article Highlights

  • There are different forms of dementia; Alzheimer’s is the most common
  • Dementia progresses in three stages: Mild (early-stage), Moderate (middle-stage), and Severe (late-stage)
  • The 7-stage model of dementia which breaks down the cognitive decline is useful for Alzheimer’s
  • The Clinical Dementia Rating Scale (CDR) can be used to assess other forms of dementia (e.g. Lewy Body Dementia)
  • The progression of dementia can vary widely by the type of dementia and by person
  • Understanding the stages of dementia can help guide care needs as the disease progresses



There are several different types of dementia, with Alzheimer’s disease being the most common. When thinking about the progression of dementia, it is useful to categorize the disease trajectory into mild, moderate, and severe stages. While different individuals will have unique experiences in each stage, understanding what to expect along the way can be helpful for care planning. In addition, knowing where a loved one falls on the scale can help determine the most appropriate treatment plan.
Dementia is an umbrella term used to describe several different types of cognitive decline. Different forms of dementia have their own symptoms and patterns of progression. Dementia is also an individual experience, so it is important to recognize that the symptoms and rate of disease progression can also vary widely across people.

While looking at a list of the changes and difficulties that may be in store can be daunting, knowing what to expect can be extremely important for the person with dementia, their families, and care partners.

The 3-Stage Model of Dementia

One of the most common ways to categorize the dementia experience is through the use of a three-stage model characterized by mild (early stage), moderate (middle stage), and severe (late stage). Since Alzheimer’s disease is the most prevalent form of dementia (60-80% of cases), these commonly attributed stages are often used to depict the experience of Alzheimer’s disease rather than other types of dementia.

To provide a more comprehensive overview, we have included a description of how symptoms at each stage can vary in different types of dementia, including vascular dementia, dementia with Lewy bodies, and frontotemporal dementia. These different types of dementia can be distinguished by unique symptoms, especially in the early stages as different parts of the brain are affected first. Gradually, as the brain damage spreads, different types of dementia and their symptoms begin to look more alike.


Mild or Early Stages

Alzheimer’s Disease

In the early stage of Alzheimer’s disease, symptoms typically include forgetfulness, losing or misplacing things, and difficulty finding the right words. Individuals with early stage Alzheimer’s might not be able to recall a recent conversation or the name of a familiar object, even though it might be on the tip of their tongue. While it is not uncommon to occasionally experience these memory problems as one ages, they become disturbing when they occur more frequently and begin to interfere with the individual’s daily life and activities. Individuals with early stage Alzheimer’s may also become easily confused, or show poor judgment with planning and decision-making.

Vascular Dementia

Early stage vascular dementia slightly resembles Alzheimer’s, although instead of being primarily characterized by forgetfulness, it is more associated with difficulty planning, decision-making, and following steps. Other early symptoms include slower speed of thought, difficulty maintaining focus, and increased likelihood of experiencing anxiety, depression, and mood swings. Following one or more strokes, Vascular dementia may also include physical symptoms such as vision or speech problems and weakness in limbs, although these symptoms might show improvement with rehabilitation.

Dementia with Lewy Bodies (LBD)

Lewy Body Dementia can also look a little like Alzheimer’s in the early stage, although there are some key differences. In the early stage of Dementia with Lewy bodies (LBD), the individual’s attention and awareness can fluctuate greatly from day to day, or even from moment to moment. Many also have recurrent visual hallucinations that they are able to describe in vivid detail, and some have auditory hallucinations as well. Sometimes these can lead to faulty perceptions and delusions of persecution.

Parkinson’s Disease

Parkinson-type motor skills problems (e.g. slowness, stiffness, tremors) are also common in people with dementia with Lewy Bodies (LBD) and are often present at the time of diagnosis.

Frontotemporal Dementia

The early stage of frontotemporal dementia has different symptoms as memory and cognitive functioning are relatively spared. Behavioral variant frontotemporal dementia (bvFTD) primarily influences individuals’ behaviors and emotions. Common behavioral changes include becoming uncharacteristically selfish, apathetic, and uninhibited. Over-eating can also be a problem.

Individuals with bvFTD might act impulsively and inappropriately in social situations, disregarding manners. There are two other less common forms of frontotemporal dementia with different initial symptoms. Semantic dementia primarily affects ability to recall names and understand language, and progressive non-fluent aphasia affects individuals’ abilities to produce fluent speech.


Early signs…

Georgia (Alzheimer’s Disease)

Georgia began to realize something might be wrong a few weeks ago when she drove to her office and, for the life of her, couldn’t remember why she was stopping there on a Saturday. She had noticed other little changes too over the past few months – like forgetting names here and there and misplacing her keys, but chalked them up to getting older. It wasn’t until she drove the 30 minutes to her office and couldn’t remember why she had come that she began to worry. However, she didn’t want to worry her husband, Peter, or their children, or confront the possibility of something being seriously wrong, so she didn’t tell anyone about these problems until eventually they became more difficult to conceal.

Ned (Vascular Dementia)

Still teaching at age 73, Ned is one of those people who “never stops,” so it’s incredibly frustrating for him now that something seems to be slowing him down. He needs to draw up a new lesson plan for his English class, which usually takes an hour or two, but it’s already been four hours and he’s only halfway through. He keeps getting distracted and losing focus. He has already changed his mind twice and had to start over. His mind keeps drifting, for example to the incident the other day in class, when he got his words all jumbled in front of his students and they laughed. He also laughed with them at the time, but he felt embarrassed. Usually cheerful, he has become depressed and anxious – mostly because he fears something isn’t right but can’t bear the thought of no longer teaching.

Lily (Dementia with Lewy Bodies)

Jim has become increasingly concerned about his wife Lily. Last month when she returned from a bike ride, he asked her where she rode, and she couldn’t seem to remember. He tried to press her, but she just seemed very confused. A few hours later, it was as if she returned to awareness, and if she hadn’t been equally as upset about the situation, he would have thought she was kidding him! But he noticed a couple of other changes in recent months too. She never used to talk in her sleep, and over the last few months, her outbursts have woken him several times. It also seems to take her a couple extra minutes in the morning to “awaken” and become alert. He has also detected a slight change in her walk, in that she seems a little unsteady and almost fell last week.

Bill (Frontotemporal Dementia (behavioral variant))

Mary didn’t think Bill could have dementia because he was only 55 and his memory seemed fine! However, she was feeling hurt lately because of the way he was suddenly treating her. Bill had always been a caring, sensitive partner, but recently, he acted selfishly and apathetic. Last week, she was upset about a fight with their son, but when she turned to him as usual for comfort, he dismissed her and seemed generally uninterested. And just last night, when their friends were over for dinner, he insulted her friend with a candid comment that previously he would have waited to utter jokingly after they’d left. Mary was mortified! He doesn’t seem to be aware that anything is different, but she knows he is not acting like the person she’s been married to for 40 years and she doesn’t understand why.

Final thoughts on the early stage

In the early stage of dementia, individuals may start to realize something is wrong, but may be able to cover up their symptoms or compensate for these difficulties. For example, those with early stage Alzheimer’s may be able to use strategies such as phone reminders, post-it notes, and other tools to compensate for their memory problems. Individuals in this early stage of dementia can typically still function independently, but difficulties, such as memory lapses or moments of confusion, will eventually begin to have a more significant impact on their daily lives.


Moderate or Middle Stage

In this stage, individuals with Alzheimer’s disease are more likely to experience increased confusion, greater memory loss, and worsening judgment. Individuals in this stage of the disease may exhibit confusion about orientation, such as where they are or what day it is. They may also have difficulty recalling personal information, such as their address or phone number or important dates like birthdays or anniversaries. Some individuals may also be at increased risk for wandering. In the other types of dementia, the earlier symptoms will become more pronounced (e.g. motor declines in dementia with Lewy bodies, or inappropriate behaviors in bvFTD), but the diseases also start to resemble the moderate stage of Alzheimer’s disease.

During this stage, individuals with dementia are likely to begin to need more assistance. They may need help with some basic daily tasks, such as dressing, bathing, and grooming (called activities of daily living, or ADL’s). You might also notice changes in sleep patterns, as well as in their personality and behavior. For example, individuals with dementia might experience increased paranoia or fear.

As family members and caregivers, it is important however to recognize that not all personality changes or behaviors are necessarily symptoms of the disease. Some changes (for example, increased fear, social withdrawal, and depression) may be perfectly reasonable responses to the difficult changes they are going through. It is therefore important to validate and seek to understand their feelings and behaviors whenever possible, because there may be something you as a loved one or caregiver can do to help alleviate their concerns or frustrations and improve their well-being.

Growing challenges…

Georgia (Alzheimer’s Disease)

Georgia’s memory has continued to get worse and her husband, Peter, is concerned about her safety. Last week, she left the stove on, he doesn’t know what would have happened had he not stopped home on his lunch break. She’ll call him occasionally by her father’s name, and she’ll get confused for longer periods of time. She retired from her job, but some days she wakes up and insists she will be late for work. She has also begun to need greater assistance with things like getting dressed, bathing, and preparing meals. Peter is considering hiring an in-home caregiver to help with some of the care.

Ned (Vascular Dementia)

Ned has had to stop teaching because of his cognitive decline. Normally cheerful and agreeable, he’s been irritable and agitated lately. His memory and bouts of confusion have gotten worse. The other day, he couldn’t remember the name of a new teacher at his school whom he’d met numerous times. Memory lapses like that have been happening on occasion, and the resulting embarrassment has caused Ned to withdraw from social interactions. Ned recently moved in with his daughter who grew concerned about his ability to live alone.

Lily (Dementia with Lewy Bodies )

Jim has been confused because he read that dementia is a progressive disease, but Lily keeps fluctuating between being lucid and aware, and being disoriented and confused. She pointed twice to a dog she claimed was in the backyard, but when Jim looked, there was nothing there. Yet, she was able to describe what she saw quite clearly. Her walking has gotten slower and a bit shuffled, causing her to trip over the ledge in the doorway yesterday, but luckily she was not hurt. Jim loves Lily dearly, and it is incredibly frustrating for him not knowing how best to help her.

Bill (Frontotemporal Dementia (behavioral variant))

Bill has continued to behave unusually, and these behaviors have become more frequent. He has also been acting compulsively – for example, constantly wiping and cleaning the dining table even though Mary keeps telling him it is clean. He has been eating a lot more than usual, and Mary is worried because he has gained quite a bit of weight. He has also started to become forgetful, forgetting that their son was coming to visit last weekend, and he doesn’t seem to be able to follow along very well in lengthy conversations. Mary also noticed that he no longer does the crossword puzzles that he used to love.


Severe or Late Stage

In the final stage of the illness, declines in physical functioning begin to parallel the declines in cognitive functioning. During this stage, individuals with Alzheimer’s typically lose their ability to communicate fluently or engage in conversation, though they may still be able to speak. Alongside these changes, individuals typically begin to experience a loss of their physical capabilities, including difficulty eating and swallowing, inability to control bladder and bowel movement, and difficulty walking (eventually an inability to walk).

The early differences between the various types of dementia diminish as they begin to look increasingly similar, characterized by cognitive and physical decline as well as behavioral changes (e.g. agitation, irritability).

In late stage dementia, individuals commonly require full-time assistance, or “around the clock care.” During this stage, they have increased susceptibility to infections like pneumonia, a common cause of death in individuals with dementia.

Advanced symptoms…

Georgia (Alzheimer’s Disease)

Georgia has become very thin and frail. Her memory is much worse – sometimes she doesn’t recognize Peter or their children. She has started using a wheelchair. Her husband hired a full-time caregiver to help with everyday tasks since Georgia has difficulty eating and has become incontinent. Although she can still speak, her speech and comprehension are limited.

Ned (Vascular Dementia)

Ned can no longer walk or eat without help. He has become physically weak and needs assistance with all basic daily activities. He often seems confused and disoriented, and he has difficulty communicating his thoughts. He has also grown more agitated. It is becoming a challenge for his daughter to care for him at home.

Lily (Dementia with Lewy Bodies)

Lily no longer fluctuates between moments of lucidity and moments of confusion. Instead, she now seems to lack clarity and awareness most of the time. Her hallucinations have become more frequent, and she has become increasingly restless. She is not steady on her feet and fell a few times. After the falls, Jim started to care for her at home full-time.

Bill (Frontotemporal Dementia (behavioral variant))

Bill’s detached behavior has become more pronounced, especially now that his memory has worsened and his ability to communicate has declined. Bill also started to have difficulty walking and seems to have become weak. Mary hired a full-time caregiver because Bill could no longer care for himself, and it became too hard for her on her own, especially since he often resists her help.


The 7-Stage Model of Dementia

You may also come across a 7-stage model of dementia (the Global Deterioration Scale). Some clinicians prefer this model, which breaks cognitive decline down into 7 more specific stages. This model can be particularly useful for Alzheimer’s disease; however it is not as relevant for other types of dementia that are less characterized by memory loss and severe cognitive decline (e.g. frontotemporal dementia).

This model consists of the following 7 stages:

  • Stage 1: No Impairment – No memory loss
  • Stage 2: Very Mild Cognitive Decline – Normal memory loss associated with aging
  • Stage 3: Mild Cognitive Decline – Friends and family members begin to notice cognitive problems
  • Stage 4: Moderate Cognitive Decline – Neurologists can confidently diagnose Alzheimer’s; poor short-term memory, may forget personal details, difficulty with simple arithmetic
  • Stage 5: Moderately Severe Cognitive Decline – Begins to need help with daily activities, significant confusion, disorientation, may no longer be possible to live alone
  • Stage 6: Severe Cognitive Decline – Worsened memory loss, difficulty recognizing family members, some personality changes
  • Stage 7: Very Severe Cognitive Decline – Final stage; communication is limited, physical systems also decline

How to identify your loved one’s current stage

The Clinical Dementia Rating Scale (CDR) is designed to evaluate the stages of dementia. It uses a 5-point scale to assess the severity of symptoms as they affect the person’s ability to function in six different cognitive categories (memory, orientation, judgment and problem solving, community affairs involvement, home life and hobbies, and personal care). Although created for those with probable Alzheimer’s disease, the CDR can also be used to assess other forms of dementia (e.g. Lewy Body Dementia). Administering the CDR can help healthcare providers gain a better sense of the severity of dementia in order to create an appropriate care plan. If you are interested in having the CDR administered, you should talk to your doctor.

How long each stage will last

There is not a clear timeline for the progression of dementia because it can vary widely by type of dementia and by person. While the average person lives 8-10 years with Alzheimer’s disease, some have lived 20 plus years after diagnosis. On average, individuals with vascular dementia typically live about 5 years after their symptoms begin. Those with Dementia with Lewy bodies typically live 6-12 years after their symptoms first develop, and those with frontotemporal dementia live an average of 6-8 years after symptoms first manifest.

However, not only is there no uniform disease trajectory, but individuals can also be diagnosed with mixed dementia, in which they simultaneously experience characteristics of more than one type of dementia. No two people are exactly the same, thus no two experiences of dementia will be exactly the same.

Why it is useful to know the stages of dementia

A categorization of dementia stage can help inform plans for treatment and care. There is currently no cure for dementia, but there are medications that may help manage or slow some of the symptoms. It can also be important to know the disease stage to determine whether your loved one may be eligible for clinical trials. Understanding the stage of dementia can also help guide care needs as the disease progresses. Typically, in the early stages of dementia, individuals can still function relatively independently. In the middle stages, they will begin to need more assistance with some activities of daily living. Eventually, in the late stage, they will need assistance with all activities of daily living.

During these later stages of dementia, the caregiver’s goals often shift to focusing on preserving the person’s comfort and quality of life. And although individuals may lose the ability to communicate, research suggests that aspects of the person and his or her “former self” still remain. This means that you may still be able to have meaningful interactions in the later stages of the disease. Suggested ways to do this include playing their favorite music or using their favorite scents – anything to foster a connection and bring them joy.

Caring for someone with dementia can be an overwhelming and stressful process. An understanding of the disease stages and what to expect along the way should provide some clarity to help family members and caregivers navigate through this difficult journey.