The Stages of Alzheimer’s: How the Disease Really Unfolds

Updated: Nov. 10, 2020

This is what caregivers can expect from loved ones at each stage of Alzheimer's disease.

Caregivers should learn all they can about the stages of Alzheimer’s

More than 50 million people in the world today suffer from the dementia of Alzheimer’s disease—and the number is expected to rise above nearly 152 million by 2050. So it’s important to understand the stages of Alzheimer’s and what to expect. The Functional Assessment Staging (FAST) scale, also called the Barry Reisberg scale named after the developer of the same name, is used by the Alzheimer’s Association and hospices to see when a patient could be hospice eligible, according to Jessica Zwerling, MD, associate director of Montefiore Einstein Center for the Aging Brain. It helps caregivers understand what stage their loved ones are at and what to expect, she says. “Other scales also exist, but FAST is easy to use and comprehend. Here are the stages of Alzheimer’s.

HIgh angle cropped view of elderly woman sleeping in bed (selective focus)
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Stages 1 and 2: Preclinical Alzheimer’s disease, normal forgetfulness

Someone in the first stage of Alzheimer’s doesn’t show any overt signs or symptoms related to thinking or reasoning, according to Verna R. Porter, MD, neurologist, and director of the Alzheimer’s Disease Program at Providence Saint John’s Health Center in Santa Monica, CA. The patient appears or feels normal and healthy, but there are internal and metabolic changes happening in the body that will only appear in medical testing, Dr. Porter says. This is similar to other medical situations, like some sexually transmitted diseases, where the health issue isn’t extremely obvious. If you or a loved one are in a high-risk category for Alzheimer’s—if there is a family history of the disease and or you’re over 60 years old—this is the time to be as proactive as possible, Sharon Roth Maguire who serves as the Chief Clinical Quality Officer at BrightStar Care adds. “This would include getting regular exercise and good quality sleep; eating a well-balanced diet focused on lean meats, fish, poultry, fruits and vegetables, healthy oils, and limiting simple sugars such as those found in baked goods and candies; maintaining cognitive stimulation and social interaction,” she says. Consider adopting these things that may slow down Alzheimer’s disease.

As the person progresses, their symptoms will still be hard to spot. The seemingly normal forgetfulness of Stage 2 Alzheimer’s disease won’t necessarily raise alarms for the person with the condition or their family members. The affected person might misplace their keys and complain about their memory, for example, but people at this stage can still do well on memory tests. (This new linguistic test might help determine someone’s risk of developing Alzheimer’s.)

Blank crossword puzzle waiting to be filled in.

Stage 3: Noticeable memory trouble due to Alzheimer’s disease

The memory loss symptoms of this stage start to progress beyond what you’d expect with normal aging. They might struggle to recall the names of new acquaintances or struggle to come up with the right word. “During this stage, a person may experience slight memory loss and confusion,” adds Stacey Barcomb, education specialist for the Alzheimer’s Disease Caregiver Support Initiative. “However, they will still have the ability to make important decisions and engage in conversations.” Some clinicians refer to this state as mild clinical impairment (MCI). Although MCI and Alzheimer’s disease do not go hand in hand, Maguire says approximately 15 percent of those with MCI are at risk for developing full-blown dementia. Note, there is some disagreement amongst doctors about diagnosing patients with MCI versus Alzheimer’s disease.

An elderly woman sadly looking out the window. Melancholy and depressed.
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Stages 4 and 5: Mild to moderate dementia due to Alzheimer’s disease

The most common symptoms of Alzheimer’s disease appear during these stages—clear, persistent, memory loss. Dr. Porter says patients with mild Alzheimer’s disease will need help with handling finances, making travel plans, or shopping for groceries to name a few. These instrumental daily activities suffer the most in the mild stages of Alzheimer’s disease, she says. Maguire notes, however, that the person with mild dementia will compensate for their memory loss or confusion to function safely in everyday life. It’s new, uncommon, or stressful events that may exacerbate symptoms revealing challenges with problem-solving. According to Barcomb, this is the time for family members or caregivers to schedule a family meeting with a physician or trained professional to discuss the diagnosis and plan for the future.

Sad senior man sitting on wooden bench outside nursing home

Stage 6: Moderately severe dementia due to Alzheimer’s disease

In this stage, your loved one might wander, not remember who you are, or how to care for themselves. “They have little to no independent functioning at home and can only do simple chores,” Dr. Porter says. Driving is unsafe at this stage of the disease, Dr. Porter adds. There is also more profound memory loss—patients only retain personal details like their high school sweetheart’s nickname, but not the name of their new hairdresser. According to Maguire, this stage is most commonly depicted in TV and movies. Their mood or behavior may change, too. “The caregiver may notice that their loved one is agitated, suspicious, or gets very upset when the caregiver leaves,” Barcomb adds. Families may need to enlist help at this stage since they can’t leave the patient alone anymore.

Hands of the old man and a young man on a white bed in a hospital.

Stage 7: Severe dementia due to Alzheimer’s disease

In the last stage of Alzheimer’s disease, the person with the condition will have severe memory loss and can no longer judge time nor place. Dr. Porter says they will require help with all tasks of daily living: bathing, grooming, using the toilet, and keeping up with personal hygiene. Maguire adds that the person may no longer be able to walk or talk and will likely be fully reliant on their caregiver at this stage. At this point, it’s time to discuss hospice care and making them as comfortable as possible, Maguire says.


Caregivers and people with Alzheimer’s need to have open discussions.

According to Barcomb, caregivers will be able to identify differences in each stage because of the increase in behavioral changes and loss of abilities. “Caregivers should review any physical, emotional, or behavioral changes they find to be new or alarming with their physician or neurologist,” Barcomb says. Dr. Zwerling adds that Alzheimer’s disease patients, and all older adults, are also at an increased risk of malnutrition, hospitalizations, and falls. Open discussions between caregivers, patients, and doctors can empower all parties in the face of this incurable disease. Next, check out the 6 signs your family member’s “forgetfulness” is actually Alzheimer’s.