American Top 40 radio host Casey Kasem who reportedly suffered from Lewy Body dementia has died. Lewy Body dementia, a type of irreversible progressive dementia, is frequently confused for Alzheimer’s disease. A diagnosis of the always fatal Lewy Body dementia is a long road for both the patient and family caregivers. On average the Lewy Body dementia patient lives five to eight years with the condition but sometimes longer. This makes for a long exhausting journey for family caregivers.