Lewy body dementia combines symptoms of Parkinson's, Alzheimer's
by Dr. Pamela Tronetti for Florida Today:I had been taught that Lewy body dementia was a single disease that affected the patient in two ways.Certainly it causes dementia: a loss of memory, function and judgment. It is a rapidly progressing disease with hallucinations, delusions and speech impairments occurring early in its progression. Often, the patient will suddenly become confused, less alert and may even fall asleep in the middle of an activity.But it also causes Parkinson’s symptoms. In Parkinson’s disease, there is damage to an area of the brain called the substantia nigra that produces a chemical called dopamine. Dopamine enables movement. It gives us facial expressions, a spring in our step, and energizes our voice and hands.Parkinson’s patients move rigidly, without any arm swing. They don’t blink, and they speak very slowly. Their writing becomes tiny, and they are prone to backward falls due to a sudden drop in blood pressure, especially when getting up from a chair.So when I saw a patient with a rapidly developing dementia accompanied by Parkinson’s symptoms, I diagnosed it as LBD.The name Lewy body harkens back to a very famous research laboratory in the early 1900s, where the study of brain tissue was revealing the mind’s mysteries. There, Dr. Alois Alzheimer found the cellular plaques and tangles that were the cellular hallmarks of Alzheimer’s disease. His colleague, Dr. Frederick Lewy, found microscopic protein deposits from dying nerve cells in the substantia nigra of Parkinson’s patients.Later research found these Lewy bodies in the cortex (grey matter) of the brain and made the connection between these diffuse Lewy bodies and the development of Parkinson’s and dementia symptoms.Although researchers usually have strict criteria for LBD, the Lewy Body Dementia Association (LBDA.org) has expanded the definition to include two other patient groups.These are:• Patients with a progressive dementia, such as Alzheimer's disease, and vascular dementia (caused by small strokes) who develop Parkinson’s symptoms later in the disease• Patients with Parkinson’s disease who later develop dementiaLBD is considered the second most common neurodegenerative dementia after Alzheimer’s disease, affecting 1.3 million Americans. However, it is often misdiagnosed or underdiagnosed.It is critical that the diagnosis be made early in the disease, so medication for dementia, movement disorder and emotional symptoms begin ASAP.Caregivers are particularly frustrated with LBD because the symptoms seem to appear and disappear. This is especially true early in the disease as the damage is progressing but before it becomes permanent.Many times they tell me, “I thought I was going crazy,” because one minute the patient is balancing the checkbook and the next minute they’re swatting flying ferrets off the ceiling. One moment they’re discussing a movie plot, and the next they nod off into another world. This is all part of the disease.So, if you know someone who shows evidence of dementia with hallucinations, delusions, speech impairments, but also has symptoms of Parkinson’s disease, including a slight hand tremor, rigidity of movement and changes in handwriting, they may have LBD. Search out a practitioner — a neurologist, geriatrician or psychiatrist — who can make the diagnosis and get them, and you, the help that’s needed.