Lewy body dementia (LBD) is the second most common progressive form of dementia. It affects thinking, movement, behavior, and even sleep. While 1.3 million Americans have LBD, most people don't know the differences between Alzheimer's disease and other types of dementia.
These are many ways that Alzheimer's and LBD differ, including these five key differences:
Alzheimer's disease causes changes in the brain called plaques and tangles. LBD features the presence of Lewy bodies, which are misfolded alpha-synuclein proteins.
In early Alzheimer's, memory loss is prominent, while in LBD memory is fairly intact. Attention and alertness are reduced in LBD, which may mimic memory problems, and problem-solving skills are highly impaired.
People with LBD experience changes in movement that resemble Parkinson's disease, such as slow, stiff movements; changes in gait or posture; and tremor. (Parkinson's disease with dementia is one form of Lewy body dementia.) With Alzheimer's disease, movement remains normal until the advanced stages.
REM sleep behavior disorder (RBD) is a risk factor for Lewy body dementias, but not for Alzheimer's disease. A person with RBD physically acts out dreams, which are often frightening, and they sometimes injure themselves or their bed partners. This can begin years or even decades before LBD dementia appears.
While someone in the advanced stages of Alzheimer's may experience hallucinations, visual hallucinations are common in LBD early in the disorder.