The 7 Stages of Dementia

The "7 stages of dementia" come from the Global Deterioration Scale (GDS), a staging tool developed by Dr. Barry Reisberg and colleagues and first published in 1982. It describes the course of Alzheimer's disease, the most common cause of dementia. Doctors and care teams use it to describe how far the condition has progressed and what kind of help a person is likely to need.

The seven stages run from no symptoms at all (stage 1) to very severe decline (stage 7). Only stages 4 to 7 are dementia. Stage 2 is normal age-related forgetfulness and stage 3 is mild cognitive impairment (MCI), which is not dementia.

The 7 stages at a glance

*Durations are the rough averages given by the scale's developer for Alzheimer's disease (stage 3 lasts about 7 years when it goes on to dementia). They describe the whole course for someone who lives through every stage, so they add up to more than the average survival after diagnosis given below. Real timelines vary widely.

The stage names can be confusing: "moderate cognitive decline" (stage 4) is mild dementia, and "severe cognitive decline" (stage 6) is moderately severe dementia. If a doctor gives you a stage, ask which scale they are using.

Stage 1: No cognitive decline

There are no problems with thinking, daily function, behavior or mood. Cleveland Clinic describes a "preclinical" phase of Alzheimer's, with no noticeable symptoms, that can last several years.

Stage 2: Very mild cognitive decline (normal age-related forgetfulness)

The person notices that names, words or where they put things are harder to recall, and may complain of poorer concentration, but other people don't notice any change. This is not dementia, and it is common in normal aging.

Stage 3: Mild cognitive decline (mild cognitive impairment)

This is the first stage with problems that people close to the person notice. Typical signs include:

• repeating the same question
• doing less well at work, or struggling to learn new skills such as using a new device
• trouble organizing something complex, such as a family event
• difficulty concentrating

Anxiety is common.

MCI is not dementia. People with MCI can still look after themselves and do their normal daily activities. According to the National Institute on Aging, an estimated 10% to 20% of people aged 65 or older with MCI develop dementia over a one-year period, but not everyone with MCI does, and in many cases symptoms stay the same or even improve. See mild cognitive impairment and cognitive decline vs. dementia.

Stage 4: Moderate cognitive decline (mild dementia)

At this stage Alzheimer's can be diagnosed with considerable accuracy. The person may:

• have trouble managing money, such as paying bills
• struggle with preparing meals, shopping or ordering in a restaurant
• forget recent events and the date

Many people can still live independently. Withdrawal, flattened emotions and denial of problems are common. This is the "early stage" described on our early-stage dementia page.

Stage 5: Moderately severe cognitive decline (moderate dementia)

This is the point where the person can no longer live independently. They may:

• be unable to recall their current address or the year
• need help choosing clothes that suit the weather or the occasion, or wear the same clothes again and again
• become angry or suspicious, especially without enough support

They can usually still dress, wash and use the toilet themselves once the clothes are chosen.

Stage 6: Severe cognitive decline (moderately severe dementia)

The person needs help with many everyday activities. They may:

• need help putting clothes on correctly, then with bathing (often the water temperature), then with toilet hygiene
• lose bladder control and later bowel control
• confuse their spouse with a parent, or not recognize close family
• have speech that breaks down toward the end of this stage
• become restless, pacing or fidgeting, have verbal outbursts, or fear being left alone; some people become threatening or aggressive

Stages 5 and 6 roughly match what is usually called the middle stage of dementia. The Alzheimer's Association says the middle stage is typically the longest and can last for many years.

Stage 7: Very severe cognitive decline (severe dementia)

In the final stage, speech is gradually lost, first to a few words and later to none. The person needs continuous help with all basic daily activities. Over time they lose the ability to walk, then to sit up without support, then to smile and to hold up their head. Muscles become stiff. Swallowing becomes difficult, and pneumonia (including aspiration pneumonia) is the most common cause of death. Around-the-clock care is needed, and hospice care may help. Read more on our end-stage dementia page.

How long does each stage last?

The durations in the table above are averages, not predictions for any one person. The Alzheimer's Association says people with Alzheimer's live on average four to eight years after diagnosis, though some live as long as 20 years. Cleveland Clinic notes that stages can overlap and that the pace depends on factors such as age at diagnosis and overall health. For figures by type, see dementia life expectancy.

A sudden change, such as confusion that comes on over hours or days, is not normal progression. It can be caused by an infection, a medicine or another illness, so contact the person's doctor promptly.

Other ways of staging dementia

The GDS is not the only system:

• Three stages (early, middle and late). The simplest and most widely used. Early roughly matches GDS 4, middle GDS 5–6 and late GDS 7. See how dementia changes over time.
• The Clinical Dementia Rating (CDR). Scores from 0 to 3, often used in research and memory clinics. See our CDR guide.
• Type-specific stages. Not every dementia follows the Alzheimer's pattern. Frontotemporal, vascular and Lewy body dementia often start with different symptoms. See the stages of Alzheimer's, vascular dementia, Lewy body dementia and frontotemporal dementia.

Why the stage matters for treatment and care

There is no cure for Alzheimer's disease, but treatment is available at every stage. According to the National Institute on Aging:

• Lecanemab and donanemab are FDA-approved for early Alzheimer's (mild cognitive impairment or mild dementia due to Alzheimer's, roughly GDS 3–4). In studies they slowed cognitive decline in some participants over 18 months. They can cause side effects called ARIA (swelling or bleeding in the brain), so people taking them need regular MRI scans.
• Cholinesterase inhibitors (donepezil, rivastigmine, galantamine) are prescribed for mild to moderate symptoms and memantine for moderate to severe Alzheimer's. They can help with some symptoms but lose effectiveness over time.

This is why getting a diagnosis at stage 3 or 4 matters: the newer medicines are only for the early stages. It also leaves time to make legal and financial plans while the person can still take part. See power of attorney and paying for dementia care.

As care needs grow, planning usually moves from support with complex tasks (stage 4), to daily supervision and help with dressing (stages 5–6), to full personal care and comfort-focused care (stage 7). If you are worried about memory changes in yourself or a family member, start with a primary care doctor, who can do an initial assessment and refer to a neurologist or memory clinic if needed.