Alzheimer's Disease
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
What is Alzheimer's disease?
Alzheimer's disease (AD) is the most common form of dementia among older people. Dementia is a brain disorder that seriously affects thinking and memory skills. If you have AD, it can impair your ability to reason or learn new skills until it becomes difficult to complete daily activities.
AD begins slowly over many years. It first involves the parts of the brain that control thought, memory, and language. It may be mistaken for normal memory changes with aging. However, AD is not a normal part of aging. The brain changes from the disease lead to symptoms that get worse over time.
What are the symptoms of Alzheimer's disease?
People with AD may have trouble remembering recent events or the names of people they know. Behavior may vary from person to person and day to day. AD progresses in stages. Late-onset AD occurs in adults aged 65 and older, which is when most people develop the disease. Early-onset AD happens before age 65, which is not common.
Some symptoms of AD can include:
- Getting lost in familiar places
- Repeating the same question
- Not recognizing family members
- Having trouble speaking, reading, or writing
- Not taking care of yourself, such as not bathing or eating poorly
In AD, over time, symptoms get worse. Later on, people with AD may become anxious or aggressive or wander away from home. Eventually, they need total care. This can cause great stress for family members who must care for them.
Who is more likely to develop Alzheimer's disease?
Researchers don't fully understand what causes AD. Age is the biggest risk factor. Your risk is also higher if a family member has had the disease. Although people who develop Alzheimer's don't always have a history of the disease in their families.
Researchers believe the causes of AD may be a combination of age-related changes in the brain, along with genetic, health, and lifestyle factors. Some medical conditions that are associated with a higher risk of AD include:
A related problem, mild cognitive impairment (MCI), causes more memory problems than normal for people of the same age. Many, but not all, people with MCI will develop AD.
How is Alzheimer's disease diagnosed?
Some health conditions can cause memory loss or symptoms like AD. Talk with your health care provider if you're having noticeable changes in your memory. To determine if your symptoms are related to AD and not normal aging or another health condition, your provider may:
- Review your medical history and any medicines you're taking
- Conduct tests to check your memory, thinking, and problem-solving skills
- Ask about changes in behavior or personality
- Do tests to rule out any medical or mental health conditions
- Refer you to a provider that specializes in caring for older adults
- Recommend a neurologist, a doctor who specializes in treating diseases of the brain and nervous system
What are the treatments for Alzheimer's disease?
No treatment can stop the disease. However, some medicines may help keep symptoms from getting worse for a limited time.
Can Alzheimer's disease be prevented?
You can't change some risk factors, like your age. But changing certain lifestyle factors may promote your brain health and help you live a healthier lifestyle overall. This can include to:
- Manage chronic health issues such as high blood pressure or hearing loss
- Get regular physical activity
- Eat a healthy diet
- Quit smoking (or don't start)
- Get enough sleep
- Develop strong social connections
NIH: National Institute on Aging
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- 10 Early Signs and Symptoms of Alzheimer's · Alzheimer's Association
- 7 Things To Know About Dietary Supplements for Cognitive Function, Dementia, and Alzheimer's Disease · National Center for Complementary and Integrative Health
- Alzheimer's Disease at a Glance · National Center for Complementary and Integrative Health
- Alzheimer's Treatment · National Institute on Aging
- How is Alzheimer's Disease Diagnosed? · National Institute on Aging
- What Are the Signs of Alzheimer's Disease? · National Institute on Aging
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