What does it mean when someone is diagnosed with "dementia?" Dementia describes a group of brain disorders that affect short-term memory and the ability to think, reason, solve problems and, eventually, the ability to speak and move.

Although the most common form of dementia in people over 65 is Alzheimer's disease, there are other types of dementia such as vascular dementia, Lewy body dementia, and frontotemporal dementia. Huntington's disease, Parkinson's disease, Creutzfeldt-Jakob disease and AIDS are other conditions linked to dementia that can cause similar symptoms

Alzheimer's Disease: Age is the main risk factor for developing Alzheimer's disease. Although the disease can strike at younger ages, it mostly affects those 65 and older. Approximately half of those over the age of 85 will develop Alzheimer's disease. What causes alzheimer's is unclear, however, it may be related to genetics and lifestyle.

Scientists believe Alzheimer's disease may result from a loss of chemical messengers or neurotransmitters (particularly a chemical called acetylcholine) in the brain. The cells responsible for producing acetylcholine begin to die off. Acetylcholine is needed in order for nerve cells in the brain to communicate properly so as the cells die and the production of this chemical decreases, a person's memory and ability to think clearly decreases. The disease begins slowly and progresses over time (usually five to eight years) and eventually destroys a person's ability to care for his own basic needs.

Lewy Body Dementia: Lewy body dementia is the second leading cause of dementia in the elderly. Lewy bodies are abnormal protein deposits in the brain and are found in the part of the brain (brain stem) where they deplete the neurotransmitter, Dopamine. This causes Parkinson-like symptoms. Over time, the abnormal proteins travel to other parts of the brain and reduce the brain's supply of acetylcholine that, in turn, affects memory, reasoning, problem solving and behavior. A person may suffer from Lewy body dementia alone or it may exist with other diseases such as Parkinson's and/or Alzheimer's.

Vascular Dementia: Vascular dementia is characterized by the narrowing or blocking of the arteries that feed the brain. The symptoms can occur abruptly, such as after a stroke or can progress very slowly and can be hard to distinguish from Alzheimer's disease. Some individuals may actually have both diseases. Like Alzheimer's disease, vascular dementia can cause problems with memory, thinking, problem solving, language and bladder control. Preventing further strokes and having treatment for high blood pressure can sometimes stop vascular dementia from worsening.

Frontotemporal Dementia: Frontotemporal dementia is a progressive disease affecting the frontal and temporal lobes of the brain, the areas of the brain generally associated with personality and behavior. Frontotemporal dementia affects judgment, the ability to reason, and social behavior as well as language, personality and some aspects of memory. Some people with frontotemporal dementia exhibit drastic personality changes, becoming impulsive and socially inappropriate; while others become unable to use or understand language. This disease tends to occur at a younger age than Alzheimer's (between the ages of 40 and 70) and early stage memory problems are not as prominent. The disease tends to be familial.

Dementia can also result from several less common brain disorders such as:

Parkinson's Disease: Parkinson's disease causes shaking or tremors while at rest, a shuffling gait, stiffness of the limbs and speech impairment. Dementia usually develops in the later stages of this disease.

Huntington's Disease: Huntington's disease is a hereditary disorder that usually begins between the ages of 30 and 50. As the disease progresses, a person may first experience personality changes followed by jerky, involuntary movements, clumsiness and muscle weakness. Dementia usually develops in the later stages of the disease.

Creutzfeldt-Jackob Disease: This is an extremely rare but fatal disease that is also known as transmissible spongiform encephalopathy. The disease is believed to be linked with the human consumption of beef from cattle infected with "Mad Cow Disease" or bovine spongiform encephalopathy.

Dementia is not always due to Alzheimer's disease. It is extremely important to rule out other medical conditions that can cause dementia-like symptoms and may be reversible. Conditions causing dementia-like symptoms include reactions to medications, infections such as urinary tract infections or meningitis, normal pressure hydrocepalus, thyroid dysfunction, nutritional deficiencies and/or emotional problems. A thorough medical evaluation can uncover an underlying condition that, with treatment, can reverse dementia.

There are treatment options available for dementia suffers that can help ease the symptoms. However, knowing the cause of the dementia is a crucial first step to beginning appropriate treatment.

Karen Hawthorn is social services coordinator for Westerly Adult Day Services in Westerly. You can call her at (401) 596-1336 or e-mail her at socialservices@wadsinc.com.