Lewy bodies are found in the brain in both Lewy body dementia and Parkinson's disease dementia. In Lewy body dementia, the first symptoms are like the memory disorders seen in Alzheimer's. Later the person will develop movement problems and other Lewy body symptoms. Their physical symptoms may be milder than in typical Parkinson's.
Lewy body may not cause short-term memory loss, but does cause problems with thinking, alertness and paying attention that will come and go. A sign your loved one could have Lewy body rather than another dementia is if they have symptoms of cognitive decline without the typical short-term memory issues.
Lewy body often causes hallucinations, especially in the first few years. With Alzheimer's, hallucinations usually don't happen until the later stages. People with Lewy body also have REM sleep behavior disorder, which causes them to act out their dreams and make violent movements while asleep.
Both Lewy body and Parkinson's cause problems with movement. Parkinson's doesn't cause problems with thinking and memory until the later stages of the disease - or sometimes not at all. With Lewy body, the cognitive problems start much sooner.
Treatments and medications used for Lewy body dementia are not the same as the ones used to treat Parkinson's or Alzheimer's.
There are 5 main symptoms of Lewy body dementia, that worsen over time: Cognitive impairment - (extreme swings between alert and confused, reduced attention span, difficulty with decision making, problems with visual perception - often causing falls or getting lost in familiar places-, increased trouble with tasks of daily living). Visual hallucinations - (Repeated hallucinations or delusions, like seeing shapes, people or animals that aren't there or having conversations with people who are long dead). Problems with movement - (slow, shuffling, stiff limbs, tremors, lack of facial expression). Sleep disturbances - (Insomnia, daytime sleepiness, REM sleep behavior disorder). Fluctuations in autonomic processes - (problems with bodily functions that are automatic including blood pressure, body temperature, urination, constipation, and swallowing).
Life expectancy is usually 5-7 years after the disease starts. Unlike other dementia's, Lewy body doesn't follow a pattern of stages. It worsens over time but the rate of decline is different for each person.