In Part 2 of this series, I wrote about how difficult it is to accurately diagnose Lewy body dementia (which includes dementia with Lewy bodies and Parkinson’s disease with dementia) versus Alzheimer’s or other dementias. Even though diagnosis is challenging, it’s important. Here’s why:
Lewy body dementias require specialized treatment
“People with Lewy body dementias react differently to certain medicines than do people with Alzheimer’s,” says Angela Taylor, Board Member and Chair of the Science Committee for the Lewy Body Dementia Association. “It’s important to get the differential diagnosis; it’s not okay to just have a general diagnosis of dementia. Knowing what medications are unsafe and working with doctors to avoid those medications is important.”
Sue Lewis knows this firsthand. Before her husband Harry was diagnosed with dementia with Lewy bodies (DLB), he had seizures caused by an antipsychotic medicine prescribed to control his hallucinations.
Sue also found out that medicines that help one DLB symptom may worsen another. After Harry’s medicines were adjusted to fit his DLB diagnosis, he seemed well enough to travel to Florida to visit his relatives and go fishing. Sue knew his parkinsonism symptoms [muscle stiffness, tremors, problems with coordination] would make getting through airports difficult, so she consulted with his doctors. They decided to try a low dose of Sinemet (a Parkinson’s medicine). “It didn’t do a thing for movement,” Sue says, “and it gave him more psychosis and gorked his cognition.”
Given that some medicines are not safe for people with DLB, and other medicines can have side effects that outweigh benefits, it’s helpful if care can be coordinated by a doctor experienced in treating Lewy body dementias, says Angela Taylor.
People with Lewy body dementia and their families may need specialized education and support
Because people with Lewy body dementia have sleep disorders, physical problems and hallucinations that Alzheimer’s patients might not have, and because they are sensitive to some medications, they and their families can benefit from specialized education and support.
“Greater awareness of the range of symptoms is important,” says Angela Taylor. “If you don’t know what the symptoms are, you can’t talk with your doctor about treating them. Treating the many LBD symptoms correctly can make a significant difference in the quality of life of both the patient and his primary caregiver.”
“We ‘Lewy body folks’ feel very strongly about that because we’re dealing with psychosis on top of dementia,” Sue says. “Living with a psychotic or suicidal spouse forces you to educate yourself for survival, especially if you don’t have a doctor knowledgeable about Lewy bodies.”
The Lewy Body Dementia Association sponsors 40 support groups in the U.S. and Canada. For people like the Lewises, who live in areas where these support groups are not available, the Association offers online support forums.
Psychiatric and cognitive changes associated with Parkinson’s can be understood and treated
Parkinson’s disease is also a Lewy body disorder, but people with Parkinson’s and their families often don’t know that changes in memory and thinking can be part of the disease. Education about possible changes in cognition can help people understand these symptoms and seek treatment.
Psychiatric problems such as depression and anxiety are common with Parkinson’s too. These psychiatric problems are the subject of a new book Making the Connection Between Brain and Behavior: Coping with Parkinson’s Disease by Dr. Joseph Friedman, a member of the Lewy Body Dementia Association’s Scientific Advisory Council.
Understanding the prevalence of Lewy body dementia may change research priorities
In Part 1 of this series, I wrote about how an estimated 20 to 25 percent of people with dementia have dementia with Lewy bodies (DLB), and that many people with Alzheimer’s also have a Lewy body disorder.
Dr. Friedman says difficulties in accurately diagnosing Lewy body dementias are a growing problem for Alzheimer’s and dementia clinical trials. This isn’t so much of a problem for trials of drugs to treat symptoms such as memory loss, impaired attention and reduced interest that are shared by Alzheimer’s and Lewy body patients, he says. However, “this is a much larger problem for the trials of drugs intended to slow disease progression. Obviously a drug that works by dissolving an amyloid protein will not work on an alpha-synuclein Lewy body, so if there are too many people with Lewy body dementia in an Alzheimer’s trial, a drug will look like it doesn't work even when it does.” If researchers use very strict diagnostic criteria to try to exclude people with Lewy body disorders, though, it may be hard to find enough patients eligible to participate in Alzheimer’s trials.
Even if doctors are able to make accurate diagnoses, Dr. Friedman is not totally optimistic about “disease-modifying” drugs for neurodegenerative diseases. “We now recognize that there are probably several different causes for DLB, Parkinson’s disease and Alzheimer’s,” he says, “so that even if these disorders are confirmed pathologically, it may turn out that there are different biochemical pathways that led to the same bad outcome. This means that blocking one bad pathway and stopping disease progression in one type of DLB may not do anything to another.”
Much of current research on dementia focuses on Alzheimer’s and on the possible causes of amyloid pathology. As scientists learn more about the different causes, pathways and pathologies underlying dementia, research efforts may become more broadly focused, and Lewy body dementia studies may receive more funding.