The graph above indicates the typical decline in cognitive status for Alzheimer's, vascular dementia and dementia with Lewy bodies. This graph is not intended to represent life expectancy, but the pattern of the cognitive status decline.
As you see with Alzheimer's, it is a slow and steady decline. According to the Alzheimer's Association, Life expectancy is two to twenty years with an average of eight to ten.
Vascular disease is much like stair stepping. There is a correlation between the vascular events and the decline in the disease process. As you can see above, the frequency of the decline varies based upon the frequency of the events. I was unable to find definitive estimates of life expectancy with vascular dementia.
Dementia with Lewy bodies presents an entirely different picture. The chart above indicates the "roller coaster" ride that takes place with DLB. There are periods of decline, plateaus and improvement with an overall unpredictable decline. According to the Lewy Body Dementia Association, "the average duration of LBD is typically five to eight years after onset of obvious LBD symptoms, but may range from two to twenty. It is important to remember this disorder progresses gradually over years, not days or months".
Early differentiating symptoms are shown in the chart at the very top of this blog. The is a comparison of decline in thinking abilities, planning or problem solving, sense of direction or spatial relationship, language problems and fluctuating cognition early in the disease process. The chart is reflective for LBD, Alzheimer's and Parkinson's.
Blessing to all
©2015 Robert Bowles
Robert Bowles, Jr.