Final answer:
Alzheimer's disease is the most prevalent type of dementia, followed by vascular dementia and Lewy body dementia. It is a progressive disease that leads to substantial neuron loss and is characterized by amyloid plaques and neurofibrillary tangles.
Step-by-step explanation:
The three most common types of dementia in order of prevalence are Alzheimer's disease (AD), vascular dementia, and Lewy body dementia. Alzheimer's disease is the most common cause of dementia in the elderly, with millions of Americans affected by the disease. It is a progressive neurodegenerative disease characterized by the presence of amyloid plaques, neurofibrillary tangles, and loss of neurons, especially severe in the hippocampus. Alzheimer's has both a rare early onset form, caused by genetic mutations, and a more common late-onset form, often also linked to genetic factors such as the APOE gene.
Payments for the care of Alzheimer's patients are a significant economic burden, and the number of patients is expected to rise dramatically because of the aging baby-boomer generation.