Dementia and Alzheimer’s Disease

The terms dementia and Alzheimer’s disease are often used interchangeably and mixed up by many people but there are distinct differences between them. Although the symptoms of the two conditions may overlap, it is important to distinguish them for management and treatment.

What is Dementia?

Dementia is a syndrome that comprises a set of symptoms associated with a decline in memory, thinking, orientation, comprehension, calculation, learning capacity, reasoning, and/or remembering. In other words, when an individual is said to have dementia they are exhibiting certain symptoms such as language difficulty, loss of recent memory, or poor judgment. If someone has dementia, they may have difficulty carrying out daily tasks they have performed routinely and independently throughout their lives.

According to the World Health Organization (WHO), about 47 million people worldwide have dementia and there are 9.9 million new cases ever year.

A number of diseases and injuries, which primarily or secondarily affect the brain, may cause dementia. These include vascular dementia, Parkinson’s disease, dementia with Lewy Bodies, and frontotemporal dementia. Each cause of dementia causes damage to a different set of brain cells.

In the early stages, there can be some clear differences between the diseases that cause dementia. For example, the early symptoms of dementia caused by Parkinson’s disease involve involuntary movements unlike early symptoms experienced by people with other causes of dementia. However, as the specific disease advances, more parts of the brain become affected, and the differences from one cause of dementia to another become more subtle.

What is Alzheimer’s disease?

The most common cause of dementia is Alzheimer’s disease, which is a terminal progressive brain disorder caused by the death of brain cells and subsequent brain shrinkage. Alzheimer’s disease accounts for 60-70 percent of dementia cases. It slowly leads to memory loss, confusion, impaired judgment, personality changes, disorientation, depression, and the inability to communicate. Dementia usually occurs in the mid to later stages of Alzheimer’s disease.

Main differences between dementia and Alzheimer’s disease

Dementia is not a disease itself, but it is a syndrome that consists of a group of symptoms that affect communication and performance of daily activities. On the other hand, Alzheimer’s disease is a form of dementia that specifically affects parts of the brain that control thought, memory, and language. In other words, dementia is one of the consequences of Alzheimer’s disease.

Doctors can accurately diagnose the cause of dementia in about 90 percent of cases with a thorough screening, including blood tests (to rule out other causes of dementia such as vitamin deficiency), mental health evaluations, neuropsychological testing, and sometimes a brain scan. However, Alzheimer’s disease can only be diagnosed with complete accuracy after death by performing a microscopic examination of the brain tissue for the presence of plaques and tangles.

A major difference between dementia and Alzheimer’s disease is that the latter is a non-reversible disease. It is a progressive neurodegenerative disease without any cure. On the other hand, some forms of dementia are reversible or temporary such as those caused by drug interaction or vitamin deficiency.

Note: Alzheimer’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.