The Whitworths of Arizona, bringing science to you in everyday language.

Sunday, January 11, 2015

PD and LBD Historical Timeline

If you are like me, you often wonder about how people learned about a disease. Well, the next blogs will tell you a bit about the process that went into making the Lewy body disorders known. I suspect there will be some surprises. Jim, for instance, was surprised and just HOW long we've known about Parkinson's. This timeline shows why people always know about PD and are less likely to know about LBD and why we are actually right about where we should expect to be, in that regard.

Lewy body disorders are those that are a) caused by Lewy bodies and b) can advance to dementia if it isn’t already present. Starting with the one known as a disease for the longest time and working forward, these are:

1. Parkinson’s Disease
2. Dementia with Lewy Bodies
3. Parkinson’s Disease with Dementia
4. REM Sleep Behavior Disorder
5. Non-amnestic Mild Cognitive Impairment

This week’s blog is a timeline for how the first three came to be recognized as specific diseases or disorders, and then, identified as a member of the Lewy body disorder family. Next week’s blog will address the last two.

AD 175: The Greek physician, Galen, described the symptoms of Parkinson’s disease and called it “shaking palsy.”

1657: English philosopher, Thomas Hobbes, described his illness in symptoms that match what those of shaking palsy.

1817: Dr. James Parkinson, a London doctor, a published “An Essay on the Shaking Palsy,” which established Parkinson’s disease as a recognized medical condition. Parkinson's had based his book on observations of six men. He recommended that someone do further study.

1868-1881: Fifty-plus years later, Dr. Jean-Martin Charcot, the “father of French neurology,” studied shaking palsy and renamed it “Parkinson’s disease” after Dr. Parkinson.

1886: Sir William Gowers, an English neurologist, published this illustration of a man with Parkinson’s in his Manual of Diseases of the Nervous System.

1912: Dr. Fredrick Lewy, a neurologist working with Dr. Alzheimer, published a paper describing abnormalities in the brain cells of people who died with shaking palsy. Eventually, these anomalies were named Lewy bodies, after Dr. Lewy.

1976: Dr. Kosaka, a Japanese psychiatrist, described the symptoms of “dementia with Lewy bodies” (DLB). Two years later, he followed this up with autopsied cases, showing Lewy bodies in the cerebral cortex. (Dr. Kosaka is retired but is still an honorary member of the Lewy Body Dementia Association’s Scientific Advisory Council.)

1994: Dementia is recognized as a symptom of Parkinson’s—Parkinson’s disease with dementia (PDD). Prior to this, it was though to be a separate disease, usually Alzheimer’s that was co-existing with the PD.

1996: Dementia with Lewy bodies (DLB) is recognized formally as a disease. Doctors can now diagnose it and charge for its treatment. Previously, even if a doctor did recognize DLB, he/she would likely document a diagnosis of AD to simplify insurance reporting.

2005: Lewy body dementia is recognized as an umbrella term for both PDD and DLB, with the same cause and the same possible symptoms.

2006 or so: Dementia specialists go from saying that "Lewy bodies that are always present in LBD" to agreeing that they are a major cause of the disorder.

2010: LBD is recognized at the second more common degenerative dementia, second only to Alzheimer's, but the general public is still mostly unaware of its existence.

2011: Researchers suggest that Lewy bodies are caused by a combination of genetics and environment (herbicides, insecticides, etc.).

2014: The PD community prefers to say that PD is caused by the genetics/environment combination, ignoring the Lewy bodies that link PD to LBD.

2014: It’s been 18 years since DLB was recognized as a specific disease in 1996. With the diagnosis of LBD in several celebrities, including Casey Kasem and Robin Williams, the general public is becoming aware of the disorder.

As you can see from this timeline, it can take many decades or more for a disease to travel from being discovered, to being recognized as a specific disease. It usually takes about 20 years for a disease to go from being recognized scientifically to being commonly known by the general public.  We are right on track!

For information about Lewy body disorders, read our books:

A Caregivers’ Guide to Lewy Body Dementia

Managing Cognitive Issues in Parkinson’s and Other Lewy Body Disorders

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