Types of Dementia

The term ‘dementia’ is an umbrella term used to describe the symptoms of cognitive impairment. And within the dementia umbrella, there are many different variations – Alzheimer’s included. Most of people don’t realize that all dementia is not Alzheimer’s.

1. Alzheimer’s Disease. This is the most common type of dementia. I like to describe Alzheimer’s as a slow process of going backwards in time. While it begins with short term memory loss (and thus, repeating oneself- because the person doesn’t remember what has just happened or what they’ve just said), the person essentially goes back to earlier days, because the days of the present are no longer remembered. Long term memory remains strong while short term memory evaporates. This explains why someone ‘doesn’t recognize’ their spouse, for example. If the resident feels and believes that they are now 50 years old instead of 90, and a gray haired gentleman tells her that he is her husband, she may reject the idea vehemently. People with Alzheimer’s demonstrate trouble with thinking and reasoning, and may have little or no orientation to time. They live in the present- emotionally- and may do things that make no sense at all. The process of Alzheimer’s has been divided into 7 stages which begin with simple confusion and in later stages the person has lost significant abilities (to swallow, for example) and full time care is needed.

2. Lewy Body Dementia (or Dementia with Lewy Bodies). Lewy Body Dementia is another very common, yet frequently misdiagnosed, or undiagnosed type of dementia. A simplified explanation for what LBD looks like is that it is described as a combination of Parkinson’s symptoms with Alzheimer’s symptoms. The stiffness or rigidity typically associated with Parkinson’s combines with the cognitive decline associated with Alzheimer’s. In addition to these outward traits, one of the primary identifying factors of LBD is visual hallucinations. The hallucinations typically are of smaller people (children) or animals, and are not upsetting to the person with LBD. Problems with sleep patterns – waking throughout the night or the acting out of dreams are other identifying factors. People with Lewy Body also experience fluctuating cognition- meaning that they can have moments or periods of clarity, and make complete sense- followed by other times of confusion and nonsensical thinking. Lewy Body Dementia causes its victims to be extremely sensitive to anti-psychotic medications which can typically help those with either Parkinson’s or Alzheimer’s. These medications can create potentially fatal conditions for those with LBD.

3. Vascular Dementia. This type of dementia- which is sometimes called “Post Stroke Dementia” is quite different from Alzheimer’s or Lewy Body Dementia. Vascular Dementia is actually brain damage traced to cardiovascular problems, or mini-strokes that caused bleeding or harm in the brain. The most outstanding symptoms that identify Vascular Dementia are when drastic changes occur immediately following a stroke. Changes can be in personality, thinking or reasoning- all depending on the area of the brain that has been affected. Trouble with paying attention, organizing thoughts, or analyzing situations can all be symptoms of Vascular Dementia. So simply put, Vascular Dementia presents itself mostly through cognitive changes, which are the result of brain damage. The use of medications has been shown to prevent or slow further brain damage, therefore control the progress of Vascular Dementia.

4. FrontoTemporal Dementia. FTD occurs when there is deterioration to the Frontal and Temporal Lobes of the brain. The person experiences problems with language, and significant changes in their personality and behavior. Where the Temporal lobe affects how one behaves or reacts in the world, based on outward input- the Frontal lobe has to do with cognitive and emotional processes, and voluntary movement. The executive functions of the brain including planning, judging, or analyzing are all housed in the Frontal lobe. When someone has FTD, they slowly withdraw into themselves. Initially they may lose inhibitions, and behavior and actions can be shocking. As the disease progresses, they tend to lose interest in others around them, and their surroundings. Their emotions become empty- there is a lack of sadness, or depression, and little to no awareness of the needs of others. Verbal and communication skills are predominantly weak and decrease significantly over time.

5. Parkinson's Dementia. The brain changes caused by Parkinson’s disease begin in a region that plays a key role in movement, leading to early symptoms that include tremors and shakiness, muscle stiffness, a shuffling step, stooped posture, difficulty initiating movement and lack of facial expression. As brain changes caused by Parkinson’s gradually spread, they often begin to affect mental functions, including memory and the ability to pay attention, make sound judgments and plan the steps needed to complete a task.The key brain changes linked to Parkinson’s disease and Parkinson’s disease dementia are abnormal microscopic deposits composed chiefly of alpha-synuclein, a protein found widely in the brain with a normal function not yet known.

6. Korsakoff syndrome. Thiamine helps brain cells produce energy from sugar. When levels fall too low, brain cells cannot generate enough energy to function properly. Korsakoff syndrome is most commonly caused by alcohol misuse, but can also be associated with AIDS, cancers that have spread throughout the body, chronic infections, poor nutrition and certain other conditions. It is also common in people whose bodies do not absorb food properly (malabsorption). Korsakoff syndrome causes problems learning new information, inability to remember recent events and long-term memory gaps. Memory difficulties may be strikingly severe while other thinking and social skills are relatively unaffected. For example, individuals may seem able to carry on a coherent conversation but moments later are unable to recall that the conversation took place or with whom they spoke. Those with Korsakoff syndrome may "confabulate," or make up, information they can't remember. They are not "lying" but may actually believe their invented explanations. Scientists don’t yet understand the mechanism by which Korsakoff syndrome may cause confabulation. The person may also see or hear things that are not there (hallucinations).