What’s the Difference between Alzheimer’s Disease and Dementia?

People often ask us, “what’s the difference between Alzheimer’s disease and dementia?” Are they the same thing? Is Alzheimer’s disease a type of dementia? Is dementia a type of Alzheimer’s disease? Well actually, Alzheimer’s disease is a CAUSE of dementia.

Dementia is an umbrella term used to describe a set of symptoms. Dementia is not a disease in and of itself, it is actually a syndrome. This collection of symptoms are caused by something else. Alzheimer’s disease is one of the possible causes. Other causes of dementia may include Lewy bodies, hypertension (or high blood pressure), and concussions.

Dementia is a progressive syndrome, primarily affecting older adults aged 65+, characterized by cognitive decline that ultimately affects a person’s ability to live independently.

There are 3 key ideas in this definition of dementia:

  1. Dementia is progressive in nature, meaning that it will get worse to the point of death.
  2. Dementia affects cognition, or any function produced by the brain, including memory, judgement, decision making, visual and auditory perception, and behaviour.
  3. Dementia reduces a person’s ability to live on their own because that person now has difficulty getting dressed, eating, going to the bathroom, showering, moving about the house, and getting up and down from a chair or a bed. These are the activities of daily living.

Alzheimer’s disease is characterized by plaques and tangles in the brain. These deposits interfere with brain function which affect memory, sequencing ability, judgment, and many other cognitive functions. Alzheimer’s disease is progressive, as more and more brain cells are affected by the plaques and tangles. This means that symptoms get worse and the need for assistance in daily life heightens.

plaques and tangles

As mentioned above, there are many other causes of dementia. You may have heard of Vascular dementia. This dementia is caused by any condition that affects the vasculature, or blood vessels in your body. For example, cardiovascular diseases like high blood pressure and heart disease can cause vascular dementia. The most common cause of vascular dementia is a stroke. A stroke is when something blocks the blood flow to the brain partially or completely resulting in reduced blood flow to the brain. When the brain (or any part of your body for that matter) doesn’t have enough blood, it starts to degenerate. That means crucial brain cell connections are destroyed and this results in symptoms like memory loss, impaired judgment, and difficulty with communication.

So, dementia is not a disease in and of itself. It is a set of cognitive symptoms that are caused by another illness or condition. Alzheimer’s disease is a cause of dementia.