Dementia, What Is It?

Dementia basically means or refers to a loss of cognitive function or cognition, due to changes in the brain caused by disease, infection or trauma. These changes may occur gradually or quickly; and how they occur may determine whether the dementia is reversible or irreversible. Irreversible dementia is caused by an incurable condition like Alzheimer’s disease. Patients with irreversible dementia are eventually unable to care for themselves and may require round-the-clock care. Cognition is the act or process of thinking, perceiving, and learning. Cognitive functions that can be affected by dementia include some of the following:

  • Thinking or acts of reasoning
  • Verbal Communication
  • Spatial orientation
  • Decision making and judgment
  • Memory

Dementia is not a disease itself, but rather a group of symptoms that might accompany certain diseases or conditions. Symptoms also might include changes in personality, mood and behavior. Dementia is irreversible when caused by disease or injury, but might be reversible when caused by drugs, alcohol, hormone or vitamin imbalances, or depression.

Causes Of Dementia

There are many causes of dementia, including neurological disorders such as Alzheimer’s disease, blood flow-related or vascular disorders such as multi-infarct disease, inherited disorders such as Huntington’s disease, and infections such as HIV. Some of the more common causes of dementia include:

  • Depression
  • Chronic drug use
  • Certain types of hydrocephalus, an accumulation of fluid in the brain that can result from developmental abnormalities, infections, injury or brain tumors
  • Infections that affect the central nervous system like HIV and Jakob disease
  • Vascular disorders (usually caused by multiple strikes in the brain
  • Degenerative neurological diseases such as Alzheimer’s, Parkinson’s and Huntington’s

Alzheimer’s disease causes 50 to 70 percent of all dementia. However, researchers are finding that some of what was previously considered Alzheimer’s is really one of two other degenerative diseases: Lewy body disease and Pick’s disease. There are also a number of other important disorders that can lead to dementia. Some of these are potentially reversible, at least partially, and should be considered before a diagnosis of Alzheimer’s disease is made.

Dementia, Is It Treatable?

Alzheimer’s is the most common cause of dementia but there are as many as 50 other known causes. Most of these causes are very rare. Some of the disorders that cause dementia may be reversible, although unfortunately most types of dementia do not respond to treatment. Therefore, it is very important to evaluate dementia symptoms comprehensively, so as no to miss potentially treatable conditions. The frequency of treatable causes of dementia is believed to be about 20 percent. Treatable causes of dementia are reversible disorders that can be cured completely, or at least partially, by treating the underlying disorder. Because some types of dementia are treatable or partially treatable, it is important not to assume that a person who is showing any symptoms of dementia is suffering from Alzheimer's disease or another incurable disease. For example, if the dementia is caused by any of the following, they are often at least partially treatable:

  • Chronic drug abuse
  • Tumors that can be removed
  • Subdural hematoma, an accumulation of blood beneath the outer covering of the brain that results from a broken blood vessel, usually as a result of a head injury (which can be minor and even unrecognized)
  • Normal pressure hydrocephalus
  • Metabolic disorders, such as a vitamin B12 deficiency
  • Hypothyroidism, a condition that results from low levels of thyroid secretion
  • Hypoglycemia, a condition that results from low blood sugar

Non-Treatable Causes Of Dementia Include:

  • Alzheimer’s disease
  • Multi-infarct dementia
  • Dementias associated with Parkinson’s disease and similar disorders
  • AIDS dementia complex
  • Creutzfeldt-Jakob disease or CJD, a quickly progressing and fatal disease that is characterized by dementia, muscle twitching and spasm.