Final answer:
As of 2013, Alzheimer's disease affects approximately 5.4 million Americans, with numbers expected to increase as the population ages, potentially reaching 13 million by 2050.
Step-by-step explanation:
According to the National Institute on Aging in 2013, Alzheimer's disease affects as many as 5.4 million Americans. This neurodegenerative disorder is the leading cause of dementia in the elderly, with projections suggesting that the number of Alzheimer's patients in the United States may rise to as many as 13 million by the year 2050. The prevalence of this condition is such that approximately one in every eight individuals aged 65 or older has Alzheimer's disease. Alzheimer's is influenced by genetic factors, with some forms caused by mutations in specific genes, but environmental elements are also believed to play a role. Research into Alzheimer's disease continues, offering hope for future treatments and a better understanding of this debilitating illness.