Dementia is classified as a breakdown of mental capacity as a result of organic deterioration, often caused by old age, chemical imbalance, or head trauma. Presenile dementia is the onset of dementia due to organic deterioration that is not a result of old age. In presenile dementia, patient's symptoms may begin appearing in individuals as young as 40 or 50, while standard dementia typically won't begin to present symptoms until after the age of 65.
The most common cause of presenile dementia is early onset Alzheimer's disease. This disease attacks the frontal lobe of the brain and slowly begins to breakdown organic brain matter, impeding or disabling the functions for which the frontal lobe of the brain is responsible. In most cases, symptoms will begin to appear slowly, gradually declining. The pace of the disease, however, tends to pick up quickly once full onset has begun, causing a steep decline in functional ability.
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Presenile dementia has many debilitating side effects, often severely depleting the quality of life for the individual suffering from it. The most common side effect is memory loss, related to both events as well as people and places. Difficulty speaking and reading can also result from presenile dementia, as the brain is slowly losing it's ability to correctly form sentences and comprehend the written word. Moods can also be drastically affected, with depression being a common side effect along with loss of judgment skills and coping abilities. Finally, basic tasks such as taking care of one's self also become more and more difficult, with hygiene problems being a frequent occurrence.
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The most common form of treatment for presenile dementia doesn't actually treat the disease itself. Doctors will often prescribe a variety of anti-depressants and other medications designed to correct chemical imbalances in the brain. The most common drugs used are those designed to boost the brain's serotonin production, a naturally occurring chemical in the brain which increases an individual's sense of well-being and overall mood. Medications intended for treating Attention Deficit Disorder may also be used, primarily given to counteract the impact on memory that presenile dementia presents in its earlier stages.
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An average person suffering from presenile dementia will typically deal with a gradual onset of symptoms over an average of ten years. In rare cases, symptoms can progress from mild to severe in just a few years. Even with prescriptions designed to minimize the early symptoms of the disease, most patients will generally have an eight to ten year lifespan once symptoms begin to present themselves. The overall range, however, can be anywhere from three to 15 years.