Dementia Vs Alzheimer's - What is the difference?

Many people use the words “dementia” and “Alzheimer’s disease” interchangeably. However, they are not the same thing.

Dementia is not a disease but rather an umbrella term for anything that can cause issues with brain functioning such as confusion, memory loss, or loss of problem solving ability. It is caused by physical changes in the brain. Alzheimer’s is a very specific form of dementia, but there are many more varieties. 


Canadian dementia expert Carol Bowlby Sifton described the difference between dementia and Alzheimer’s disease by using the following analogy. “Soup” is a general term for a category of food. Soup comes in dozens of flavours, like chicken noodle, tomato, clam chowder, or mushroom. Every can of mushroom or tomato soup is soup—but not every can of soup is mushroom or tomato.Similarly, Alzheimer’s disease is a type of dementia, but not all dementia is Alzheimer’s disease. 

Types of Dementia: 

Alzheimer’s Disease - The most common type of dementia and accounts for an estimated 60 to 80 percent of cases. 
Symptoms: Difficulty remembering recent conversations, names or events is often an early symptom; apathy and depression are also often early symptoms. Later symptoms include impaired communication, poor judgment, disorientation, confusion, behaviour changes and difficulty speaking, swallowing and walking. 

Vascular dementia - Post-stroke dementia; accounts for about 10 percent of dementia cases. 
Symptoms: Impaired judgment or ability to make decisions, plan or organize is most likely to be the first symptom, as opposed to the memory loss often associated with the initial symptoms of Alzheimer’s. This occurs because of bleeding and blood vessel blockage. The severity and location of the brain injury determines how the individual’s thinking and physical functioning are affected. 

Dementia with Lewy Bodies (DLB) 
Symptoms: Patients with LDB exhibit memory loss and thinking problems and are more likely than people with Alzheimer’s to have early symptoms such as sleep disturbances, visual hallucinations, and muscle rigidity. 

Mixed Dementia - In mixed dementia abnormalities linked to more than one type of dementia occur simultaneously in the brain. 
Symptoms: Most commonly, Alzheimer’s and vascular dementia often present in the same patient. 

Parkinson’s Disease - As Parkinson’s disease progresses, it often results in a progressive dementia similar to dementia with Lewy bodies or Alzheimer’s. 
Symptoms : Problems with bodily movements 

Frontotemporal Dementia - Includes dementia such as progressive aphasia, Pick’s disease and progressive palsy. 
Symptoms: Typical symptoms include changes in personality and behaviour and difficulty with language. Nerve cells in the front and side regions of the brain are especially affected.

Huntington’s Disease - A progressive brain disorder caused by a single defective gene on chromosome 4. 
Symptoms: Abnormal involuntary movements, a severe decline in thinking and reasoning skills, irritability and depression. 
 
It’s important that families know the type of dementia being diagnosed because different dementias have different characteristics, expectations and medications. Family caregivers should form a care team with doctors, pharmacists, and other care providers focused on providing the best possible care which includes an accurate understanding of the diagnosis, its symptoms, and its possible treatments.