What Is Alzheimer's Disease?
Alzheimer's disease is a progressive neurodegenerative disorder, meaning it slowly damages brain cells over time. It is the most common cause of dementia. Dementia is not one disease; it is a general term for a decline in memory, thinking or reasoning that is serious enough to interfere with a person's ability to manage daily life independently. Alzheimer's disease is one cause of dementia, and other causes include vascular disease, Lewy body disease and frontotemporal degeneration. So the two terms are related but not identical: Alzheimer's is a specific disease, while dementia describes the level of impairment it can cause. Alzheimer's changes can also begin years before symptoms reach the stage of dementia.
What Happens in the Brain During Alzheimer's Disease?
Researchers have identified several key changes, although the complete picture of how the disease develops is still being studied:
- Amyloid-beta, a protein fragment, builds up between nerve cells and forms clumps called plaques.
- Tau, a protein that normally helps support nerve cells, becomes abnormal and forms tangles inside them.
- Connections between nerve cells (synapses) are lost, so brain regions communicate less effectively.
- Over time, brain cells are damaged and die, and affected areas of the brain shrink.
More than amyloid
Amyloid alone does not explain every symptom. Tau changes, inflammation, blood vessel health and other factors also appear to play a role, and many older adults have more than one type of brain change at the same time.
What Are the Early Symptoms of Alzheimer's Dementia?
Early signs that families commonly notice include:
- Asking the same questions or telling the same stories repeatedly
- Forgetting recent conversations or events
- Missing appointments or forgetting plans
- Misplacing objects and being unable to retrace steps
- Trouble managing bills, checkbooks or finances
- Difficulty completing familiar tasks, such as following a recipe
- Poor judgment, or getting confused about dates or familiar places
Symptoms vary from person to person
Memory loss is the best-known symptom, but it is not the only one. Some people first show trouble finding words, judging distances, planning or organizing, or changes in mood and personality.
Is Alzheimer's Disease Normal Aging?
No. Occasional forgetfulness is common with age, but Alzheimer's disease is not a normal part of aging. The key difference is whether changes are getting worse and interfering with everyday life.
- Normal aging: forgetting a name and remembering it later. Concerning: regularly forgetting close family members' names or recent visits.
- Normal aging: occasionally misplacing glasses. Concerning: putting items in unusual places and accusing others of taking them.
- Normal aging: making an occasional bill-paying error. Concerning: being unable to keep track of monthly bills.
- Normal aging: briefly forgetting the day of the week. Concerning: getting lost on a familiar drive.
How Does Alzheimer's Disease Progress?
Alzheimer's disease usually progresses gradually over several years, though the pace differs widely. In the early stage, a person may still live fairly independently but need help with complex tasks such as finances or medications. In the middle stage, memory and confusion worsen, and help is often needed with daily routines; behavior changes can appear. In the late stage, people need help with most or all personal care. Planning early gives families time to make legal, financial and care decisions together.
How Is Alzheimer's Dementia Diagnosed?
There is no single test. A clinician typically reviews the history (ideally with input from a family member), performs an examination and cognitive testing, checks blood work for other causes, and often orders brain imaging. Biomarker tests, such as blood tests, spinal fluid tests or amyloid PET scans, can help confirm Alzheimer's changes in appropriate patients.
Can Alzheimer's Disease Be Treated?
There is currently no cure, but treatment can help. Some medicines may modestly help symptoms, and newer disease-modifying treatments may slow decline for carefully selected people in early stages. Managing sleep, hearing, blood pressure, mood and physical activity, along with caregiver support, also matters a great deal.
What Should Illinois Families Do Next?
- Write down the changes you have noticed and when they began.
- Schedule an evaluation with a qualified healthcare professional.
- Bring a full medication list and, if possible, a family member to the visit.
- Ask about other conditions that can affect memory, such as medication effects, depression, sleep problems, thyroid disease or vitamin deficiencies.
- Connect with caregiver education and local support early.
Frequently asked questions
- Is Alzheimer's the same as dementia?
- No. Dementia describes a decline in thinking serious enough to affect daily life. Alzheimer's disease is the most common cause of dementia, but not the only one.
- Is memory loss always Alzheimer's disease?
- No. Memory problems can come from many causes, including medication side effects, depression, sleep disorders and other medical conditions, some of which are treatable.
- Is Alzheimer's disease a normal part of aging?
- No. Mild, occasional forgetfulness can occur with age, but Alzheimer's disease is a disease, not normal aging.
- Can Alzheimer's disease be cured?
- There is no cure yet, but medications, newer treatments for early-stage disease, healthy habits and caregiver support can help.
Finding Alzheimer's and Dementia Support in Illinois
Families often benefit from memory evaluations, caregiver education, community support programs, dementia care planning and local aging and caregiver resources. These pages can help you get started:
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Learn More About Alzheimer's Disease and Dementia
Explore Illinois Dementia Guide for information about dementia symptoms, diagnosis, treatment options, and resources for families and caregivers. Watch additional educational videos as they become available in our dementia video library.
This website provides educational information and does not replace individualized medical evaluation, diagnosis, or treatment. Consult a qualified healthcare professional about memory concerns. If you believe someone is experiencing a medical emergency, call 911.