The average progression from mild to severe Alzheimer’s disease is 6 years. At this time, a patient will be in need of care equivalent to placement in a health-related facility, such as a nursing home.
Stern Y, Tang M, Albert M, Brandt J, et al. Predicting Time to Nursing Home Care and Death in Individuals with Alzheimer Disease. JAMA. 1997; 277(10): 806-812. http://jama.ama-assn.org/cgi/content/abstract/277/10/806