Dementia, Mild Cognitive Impairment (MCI), and Alzheimer's Disease - What's the Difference?

Dementia is an overall term that describes a range of symptoms that can be due to different diseases.

The most common symptoms include problems with memory, language, problem-solving, and other thinking skills. These symptoms can affect a person’s ability to do everyday activities.

Alzheimer’s is a specific type of dementia.

Alzheimer’s disease is the most common form of dementia.

Alzheimer’s disease is the most common form of dementia, but not everyone with dementia has Alzheimer’s disease. There are also other forms of dementia, including Lewy body dementia, frontotemporal dementia, vascular dementia, and mixed dementia.

Mild cognitive impairment (MCI) is an overall term that describes symptoms that can be due to different causes.

MCI is when a person has minor problems with memory and thinking, but most of their daily activities are not affected. MCI may be caused by Alzheimer's, but there can be several causes aside from Alzheimer's, so it's important to get evaluated by a doctor.

Alzheimer’s disease progresses in 5 stages:

  • Preclinical Alzheimer’s
  • Mild Cognitive Impairment (MCI) Due to Alzheimer’s
  • Mild Alzheimer’s Dementia
  • Moderate Alzheimer’s Dementia
  • Severe Alzheimer’s Dementia

The earliest symptoms of Alzheimer’s may appear as MCI. These symptoms may be mild or may be difficult to distinguish from the signs of normal aging. That's why it's important to voice your concerns to a doctor if the symptoms begin affecting you or your loved one’s daily activities.

How Does Alzheimer’s Affect the Brain?

It can take 20 years or more after brain changes have already happened for Alzheimer’s symptoms to appear. That’s why it’s important to talk about brain health and changes in memory and thinking that affect your or your loved one's day-to-day activities during annual wellness visits.

Alzheimer's symptoms are caused when certain nerve cells called “neurons” no longer work properly. There are two proteins associated with brain changes in Alzheimer’s: beta-amyloid and tau.

  • Beta-amyloid clumps together outside of neurons. These clumps are called “beta-amyloid plaques”
  • Tau clumps together inside the neurons. These clumps are called “tau tangles”

As Alzheimer’s worsens over time, other neurons can’t function properly. The first signs may be memory problems that disrupt work, life, and social activities. The neurons that allow a person to do basic things like walking and swallowing can eventually be affected. As symptoms progress, people with Alzheimer’s disease may need full-time care.

Stages of Alzheimer’s Disease

Discover the 5 stages of Alzheimer’s disease and how they may affect you or your loved one.