What is the difference between Alzheimer’s disease and dementia?   These terms are often used interchangeably, but they are not different names for the same disease.   Alzheimer’s is a disease that causes specific changes in the human brain. By contrast, dementia is not a disease, but a group of symptoms that indicate an underlying problem with the brain.

If you are experiencing symptoms of dementia, it is important to be evaluated by a physician to determine the cause, because some causes of dementia are treatable.

What is Alzheimer’s Disease?

Alzheimer’s disease is characterized by abnormal build-ups of amyloid (Abeta) and tau proteins in the brain. The Abeta proteins cause plaques to form on brain neurons; the tau proteins, which form later in the disease process, cause tangles to form within brain neurons.  The disease process is very slow and is likely to occur over many years.

The behavioral attributes of Alzheimer’s disease include:

• Loss of short-term memory;
• Increasing need for assistance in performing normal daily activities due to mental confusion; and
• Inability to organize, plan or follow directions.

Scientists do not know what causes the body to generate high levels of Abeta and tau proteins.  However, researchers know that those with high levels of both these proteins  show the behavioral attributes of Alzheimer’s, and that over time, their brains atrophy, initially in the hippocampus region of the brain, then spreading to other areas of the brain.

What is Dementia?

Dementia is not a specific disease, but a constellation of symptoms that indicate the presence of an underlying problem with the brain.  Clinicians define dementia as 1) memory loss and 2) persistent trouble with at least one other key cognitive function, such as planning, problem solving, or organization. Therefore, someone with Alzheimer’s disease will exhibit the symptoms of dementia.  However, not everyone with dementia has Alzheimer’s.

Other Causes of Dementia

People with symptoms of dementia could have any one of the following medical problems:

• Alzheimer’s Disease
• Stroke
• Parkinson’s Disease (Lewy Body Disease)
• Picks Disease
• Traumatic Brain injuries
• Thyroid malfunction
• Vitamin deficiencies
• Adverse drug reactions
• Brain tumors

Why is it important to know what is causing the dementia?

Some causes of dementia, including thyroid malfunctions, vitamin deficiencies, and adverse drug reactions, are treatable.  Therefore, it is important to figure out what is causing the cognitive trouble to allow for effective treatment.  If the mental confusion develops quickly, you should not assume it is Alzheimer’s disease and seek a medical evaluation.

Even if the cause of dementia is not treatable, it is helpful to pinpoint the cause because different causes have additional symptoms and needs, and different diseases have different trajectories.