Similarity and difference: Alzheimer’s and other types of dementia have some things in common, but they also differ from each other. However, mixed forms are also common, for example between Alzheimer’s and vascular dementia. Then the illness signs overlap. In this article you can read more about the difference between Alzheimer’s and other types of dementia.
Many people wonder what the difference between dementia and Alzheimer’s is – on the assumption that they are two different clinical pictures. In fact, Alzheimer’s is a form of dementia, just like vascular dementia and Lewy body dementia, for example. So the question should actually be how Alzheimer’s disease and other forms of dementia differ from one another.
Difference: Alzheimer’s & Vascular Dementia
Alzheimer’s disease and vascular dementia are the two most common forms of dementia. The main differences between the two relate to the onset and course of the disease: Alzheimer’s dementia begins insidiously and the symptoms slowly increase. Vascular dementia, on the other hand, usually begins suddenly; the symptoms often increase by leaps and bounds, but sometimes also insidiously and slowly as in Alzheimer’s disease.
- When it comes to gender distribution, there is no certain difference in Alzheimer’s disease. In contrast, vascular dementia is more common in men.
- Patients with vascular dementia often have a history of stroke; Alzheimer’s patients usually do not.
- Paralysis and numbness are common in vascular dementia, while they are usually absent in Alzheimer’s dementia.
Often the two forms of dementia mix
As clear as the theoretical differences between Alzheimer’s and dementia of the vascular form are, the reality is often different. Because many patients do not suffer from a pure form of one form or another of dementia, but from a mixed form. Vascular dementia rarely occurs without Alzheimer’s changes. This means that the clinical pictures can overlap, which makes diagnosis more difficult.
Alzheimer’s & Frontotemporal Dementia
There are both similarities and differences between Alzheimer’s dementia and frontotemporal dementia. Some examples:
- While Alzheimer’s usually occurs from the 7th decade of life, frontotemporal dementia often manifests itself earlier (in the 5th to 7th decade).
- The progression of frontotemporal dementia is on average somewhat faster than that of Alzheimer’s.
- Alzheimer’s disease rarely occurs in families, whereas frontotemporal dementia is common (in around 50 percent of cases).
- The hallmark of Alzheimer’s is a memory disorder. In contrast, frontotemporal dementia develops relatively rarely. Other symptoms are in the foreground here, such as “neglect” and poor personal hygiene. In the case of Alzheimer’s, however, personality changes are usually only clearly noticeable at a late stage.
- Frontotemporal dementia is very often associated with reduced drive, euphoria / disinhibition and a lack of insight into the disease. Such symptoms are rare in Alzheimer’s disease.
- Disturbances in facial recognition, language and speech, as well as incontinence usually appear late in Alzheimer’s disease, and early in frontotemporal dementia.
- In Alzheimer’s dementia, movements and actions are already disturbed in the early stages of the disease. Frontotemporal dementia is rarely associated with such apraxia.
- Alzheimer’s patients rarely show restlessness and only in later stages. People with frontotemporal dementia, on the other hand, are often restless even in the early stages.
Difference with regard to dementia with Lewy bodies
Alzheimer’s dementia and Lewy body dementia are also similar in many features, which is why the latter was not considered an independent disease for a long time. It is now recognized as such, because there are also differences between Alzheimer’s and dementia with Lewy bodies. The most important are:
- The condition of Alzheimer’s patients worsens slowly and more or less steadily. The course of Lewy body dementia, on the other hand, is often fluctuating, especially when it comes to attention.
- Memory disorders show up early in Alzheimer’s disease, and often late in Lewy body dementia.
- Visual hallucinations, as they occur very frequently and early in Lewy body dementia, are rarely early symptoms in Alzheimer’s disease.
- Lewy body dementia is often associated with Parkinson’s symptoms early on (especially rigor). In Alzheimer’s disease, these only occur in later stages, if at all. Other neurological symptoms are also rare here. People with Lewy body dementia, on the other hand, suffer from repeated loss of consciousness and sleep disorders (including actual action of the dream content).
- The hypersensitivity to neuroleptics (agents against hallucinations, delusion, confusion, etc.) is another clear difference between Alzheimer’s disease and dementia with Lewy bodies: people with Lewy body dementia tolerate these drugs poorly or not at all, while Alzheimer’s patients do.
In practice, however, the difference between Alzheimer’s and Lewy body dementia is not always so clear. In the meantime, a variant of Alzheimer’s has been discovered in which not only Alzheimer’s plaques but also Lewy bodies form in the brain. The symptoms can then overlap.