What is Alzheimer’s disease?

How Alzheimer’s shows up day to day

Early on, your loved one may repeat questions, forget a conversation from this morning, or lose track of the date while remembering 1975 vividly.

Over time, multi-step tasks like cooking a full meal or managing medicines become hard. In the middle stages, Mayo Clinic describes increasing confusion, restlessness late in the day, suspicion, and the need for help with dressing and bathing.

In the late stage, people need help with nearly everything, and walking and swallowing become difficult.

Some abilities, like enjoying music, telling old stories or drawing, often last much longer. Those are the doorways to connection.

Early signs of Alzheimer’s disease families notice

Forgetting recent events or conversations is often the first sign. Mayo Clinic groups the other early changes into a few areas:

One sign alone means little. A pattern that keeps getting worse is the reason to book a medical evaluation.

Why it happens

Mayo Clinic explains that beta-amyloid clumps disrupt communication between brain cells, while tau proteins form tangles that block the cells’ internal transport. The changes begin years before symptoms. Age is the strongest risk factor; family history, the APOE e4 gene, heart and blood-vessel risk factors, untreated hearing loss and poor sleep also play a part. Fewer than 1% of cases come from specific inherited gene changes.

Mayo Clinic adds that more than 70% of Americans 65 and older with Alzheimer’s are 75 or older, and that Alzheimer’s accounts for an estimated 60% to 70% of the more than 55 million people living with dementia worldwide.

Figures are from the Alzheimer’s Association 2024 Facts and Figures and the CDC. More Florida numbers are on our Florida dementia statistics page.

The stages of Alzheimer’s disease

The Alzheimer’s Association says people live an average of 4 to 8 years after an Alzheimer’s disease diagnosis, though some live as long as 20. The stages are a rough guide; they overlap, and no two people follow exactly the same path.

Early (mild) stage

Your loved one may still drive, work and socialize. Word-finding trouble, misplacing valuables and difficulty planning are common, but friends may not notice. This is the best window for legal, financial and end-of-life planning, while your loved one can take part in the decisions.

Middle (moderate) stage

Usually the longest stage, it can last many years. People may forget their own address or parts of their history, need help choosing clothes, sleep in the day and get restless at night, and wander. Personality changes, suspicion and refusing a bath are common. Simpler tasks, a home safety check and regular breaks for the caregiver help.

Late (severe) stage

Around-the-clock personal care is needed. Walking, sitting and eventually swallowing become hard, infections such as pneumonia become more likely, and telling others about pain gets difficult. Relaxing music and gentle touch still matter, and the Association recommends hospice to focus on comfort and dignity.

Risk factors for Alzheimer’s disease

These come from Mayo Clinic. Mayo adds that hearing aids are linked with lower risk, and that a Mediterranean-style diet, regular exercise and managing blood pressure, diabetes and cholesterol may lower risk, though nothing fully prevents the disease.

What helps at home

• A predictable daily rhythm, with the hardest tasks at your loved one’s best time of day.
• Short, simple sentences and one choice at a time.
• Meaningful activity: music, folding laundry, gardening, looking at photos. See our dementia activities ideas.
• Safety upgrades before they are needed, especially for wandering, stoves and driving.
• Regular breaks for the caregiver.

What works changes over time, so revisit these every few months.

Behaviors you may meet, and what they are called

Doctors and nurses often use specific words for the changes Alzheimer’s disease brings. Each links to a plain-English entry:

Naming the pattern makes it easier to look up what helps and to describe it clearly at appointments.

Complications to watch for

As Alzheimer’s disease progresses, people find it harder to report pain, describe side effects or follow a treatment plan, so the family becomes the early-warning system. In later stages, Mayo Clinic lists swallowing, balance and bladder or bowel problems that can lead to aspiration pneumonia, falls and fractures, bedsores, malnutrition, dehydration and constipation. Watch for grimacing, guarding a limb, refusing food or a sudden change in behavior, and tell the doctor.

A short example day in middle-stage Alzheimer’s disease

Our daily routine planner helps you build your own version.

When to call the doctor

See a doctor for any persistent change in memory or thinking, since some causes are treatable. After diagnosis, call about sudden changes (often infection or delirium), new falls, weight loss, swallowing trouble, or behavior that puts anyone at risk. Ask about medicines that may ease symptoms or slow decline.

What to bring to each doctor visit

• A list of every medicine and supplement, with doses
• Two to four weeks of notes on sleep, eating, mood and falls
• Your top three questions, written down
• Any new behavior, with when it started
• Copies of legal documents if they are not yet in the chart

If your loved one tells the doctor everything is fine, send a short written summary ahead of the visit instead of correcting them in the room.

First steps after an Alzheimer’s disease diagnosis

1. Ask the doctor which stage the team sees, and which medicines are options.
2. Sign a durable power of attorney and a health care surrogate designation while your loved one can take part.
3. Review driving, the stove, firearms and finances for safety.
4. Start a simple care log to track changes for appointments.
5. Line up regular breaks for the main caregiver before exhaustion sets in.

Our Florida legal and financial planning guide walks through the documents in more detail.

Florida resources for Alzheimer’s disease

Florida’s Alzheimer’s Disease Initiative, created in 1985, funds 17 Memory Disorder Clinics across 13 service areas for diagnosis and referral. It also supports respite for adults with a probable dementia diagnosis, including in-home, facility-based and emergency respite and extended stays of up to 30 days, plus caregiver training, counseling and support groups through the 11 Area Agencies on Aging. The program’s State of Florida Brain Bank, run with Mount Sinai Hospital in Miami, coordinates brain donation for research.

To start, call the Elder Helpline at 1-800-963-5337. The Alzheimer’s Association Helpline, 800-272-3900, is free, Open day and night and offers interpreters in more than 200 languages. More numbers by region are in our Florida dementia resources directory.

Alzheimer’s vs. dementia

Dementia is the umbrella term for a decline in thinking that disrupts daily life. Alzheimer’s is one disease that causes it, the most common one. Others include vascular dementia, Lewy body dementia and frontotemporal dementia, and many people have a mix.

Care at home through the stages

Most people with Alzheimer’s live at home for years. A consistent dementia companion can grow with your family, from weekly outings early on to daily support later. Compare options in in-home care vs. memory care, and see our guide to the stages.

Related terms

• Mild cognitive impairment
• Sundowning
• Anosognosia
• Wandering
• Memory care
• Perseveration