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What is Alzheimer's Disease?

What Is Alzheimer's Disease?

The most common cause of dementia is Alzheimer’s disease (AD). AD is a progressive and irreversible brain disorder. The actual cause of AD is unknown. AD slowly damages a person’s memory, judgment, reasoning skills, personality, autonomy, and bodily functions. 

The disease specifically affects several components of the brain. These include:

  • a gradual loss of brain cells (neurons)
  • damage to neurons so they no longer function properly
  • the loss of neural connections (synapses) where messages are passed from neuron to neuron

Forgetfulness: A Normal Part of Aging?

It’s normal to sometimes forget things. As we age, it often takes longer to remember words or names, or where we left our glasses. These forgetful moments don’t necessarily indicate dementia. In fact, scientists have found that healthy older adults perform just as well as their young counterparts on complex and learning tests if given extra time to complete.  

There’s a difference, however, between occasional forgetfulness and behavior that may be cause for concern. Not recognizing a familiar face, trouble performing common tasks (like using the telephone or driving home), or being unable to recall recent information are red flags that need to be checked by a doctor.

Who Gets AD?

Also known as late-onset Alzheimer’s disease, AD is primarily a disease of older adults. The first noticeable symptoms can occur as early as age 60.AD sometimes can affect people as young as 30. This type of AD is called early-onset AD. It’s rare and affects less than one out of every 1,000 people with AD. When AD runs in families, it’s called familial Alzheimer’s disease (FAD). 

The underlying causes and specific risk factors for AD remain unclear. Yet experts believe AD is likely due to a combination of environmental and genetic factors. Lifestyle choices such as diet, exercise, and staying mentally active are also factors. 

About 5.2 million Americans have AD, according to the Alzheimer’s Association of America. That number will only climb as the elderly population rises.

According to the same source, AD is the sixth leading cause of death in the United States and the fifth leading in Americans age 65 and older.

What’s Being Done?

Scientists are working to better understand AD. The goal is to create more effective early diagnostic tools, improve treatments, and perhaps even discover a cure. 

Currently there are numerous resources and services for people who suffer with AD and their loved ones and caregivers. Some current treatment options even may slow the progression of AD, but their effectiveness varies and diminishes over time.

Content licensed from:

Written by: Wendy Leonard, MPH
Published on: Aug 08, 2014
Medically reviewed on: Aug 08, 2014: George Krucik, MD, MBA

This feature is for informational purposes only and should not be used to replace the care and information received from your health care provider. Please consult a health care professional with any health concerns you may have.
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