HEALTH TOPICS 
Dementia
What Is It
Dementia is a pattern of mental decline caused by different diseases or conditions. Most commonly, dementia occurs when brain nerve cells (neurons) die, and connections between neurons are interrupted. These disruptions have a variety of causes and usually cannot be reversed.
Alzheimer's disease causes over 60% of all dementias. Vascular disease, such as stroke, is the second most common cause.
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