Dementia is a medical problem characterized by the progressive loss of intellectual and cognitive abilities sufficient to result in impaired social and work functioning. Although the term dementia is usually applied to elderly people, dementia can also occur in younger adults.

Dementia is not really a disease, but is a symptom of something going wrong in the brain. In other words, dementia is what you witness in the patient’s behavior, but what is happening in the brain is the disease causing the dementia. Sometimes the disease causing dementia is actually a treatable condition. There are many potentially treatable diseases and conditions that can cause dementia, and a complete medical and neurologic examination is necessary to identify the possible causes. For example, low thyroid hormone (called hypothyroidism) can produce a dementia that can be completely cured by taking thyroid hormone tablets. This thorough evaluation for treatable causes of dementia requires extensive testing and can be rather expensive.

On the other hand, some causes of dementia are irreversible and ultimately fatal because the nerve cells in the brain die. These causes of dementia are called neurodegenerative disorders, and Alzheimer’s disease is one of many different neurodegenerative disorders that include Pick’s disease, Lewy body disease, and many others.

Alzheimer’s disease is becoming more prevalent as our life expectancy increases. For example, one out of every two people over the age of 85 years will have Alzheimer’s disease. Currently, there are over 6 million victims of this disorder in the United States and, by the year 2030, estimates suggest that number of victims will double to about 12 million.