When David was diagnosed, almost nobody we knew had heard of Lewy Body Dementia.  People assumed that LBD is similar to Alzheimer’s; for many people, dementia = Alzheimer’s.  The diseases are markedly different, though both dementias do involve misfolded proteins, and the brains of people with LBD can show the characteristic tangles of Alzheimer’s (tau and amyloid) as well as “Lewy bodies” (alphasynuclein deposits).  The symptoms differ, however, and while Alzheimer’s tends to follow a general pattern of stages, the symptoms of LBD vary widely, and symptoms can come and go.  Overviews on medical websites are informative — as long as readers have medical training or plenty of time to consult dictionaries. 

The disease characteristics overlap with those of Parkinson’s, but they also include hallucinations, REM sleep disturbances, visuo-spatial confusion, and autonomic system dysregulation.  The average lifespan after diagnosis averages five to seven years – but can be two to twenty.

LBD is progressive and brutal, a cascade of losses: loss of facial expression, loss of mobility, loss of cognitive powers, loss of friends, loss of dignity, loss of voice, loss of bladder and bowel control.