Category Archives: LBD

The Dana Foundation has just published a new online article on Lewy Body Dementia. The website’s editor says:

After Alzheimer’s disease, Lewy body dementia (LBD) is the most prevalent progressive dementia of the many cognitive disorders wreaking unspeakable havoc on millions of lives. LBD is characterized by the presence of Lewy bodies, which are abnormal aggregates of a protein called alpha-synuclein, and are found  in regions of the brain that regulate behavior, memory, movement, and personality. Many of the symptoms of Alzheimer’s, Parkinson’s, and LBD overlap, but LBD is more difficult to diagnose. Underdiagnosis is just part of the reason why LBD is unknown to the public and many health-care providers, and why funding for research lags far behind that for almost every other cognitive disorder.

While it’s a good article, I think it would be challenging reading for those who are new to LBD.  Probably most of our group members won’t have a problem with it!

The article makes a few points:

• The underdiagnosis of LBD may delay appropriate symptomatic treatments and expose patients to dangerous medications.  It also leads to a lack of LBD research.
• An early diagnosis of LBD helps families prepare.
• Though the majority of both LBD caregivers and Alzheimer’s caregivers mention “memory impairment” as the most common presenting symptom, the nature of the memory impairment is different.  “Alzheimer’s affects the ability to encode new experiences into one’s long-term memory, whereas the disorder in LBD can be one that affects retrieval of memory.”
• “If medications are employed for LBD patients, a complex and delicate degree of balance is required. Drugs that are commonly used to treat the rigidity and immobility of Parkinson’s cannot be used as liberally in dementia with Lewy bodies, since they tend to worsen hallucinations.”

These facts were new to me, and I’ll have to ask around about them:

• “[The] amount of overall pathology associated with alpha-synuclein occurs at lower levels than amyloid and tau proteins in Alzheimer’s, which makes it harder to develop lab tests that measure it.”
• “[There] are fewer genetic causes of LBD that can be used to create experimental models than there are of Alzheimer’s.”
• “It wasn’t until the development of a staining technique in the late 1990s that researchers learned how much more common LBD is than previously thought.”

There are two things that I take issue with in the article.  First and most importantly, with just about all publications about Lewy Body Dementia, there is a co-mingling of two disorders — Dementia with Lewy Bodies, and Parkinson’s Disease Dementia.  These disorders actually have separate diagnostic criteria though you wouldn’t know that from this article or from the Lewy Body Dementia Association website.

Second, RBD (REM sleep behavior disorder) seems to have slipped into being identified as a “core feature” of LBD rather than a “suggestive feature.”  (The diagnostic criteria for DLB lists RBD as a “suggestive feature.”)

Here’s a link to the article:

dana.org/news/cerebrum/detail.aspx?id=44538

Lewy Body Dementia: The Under-Recognized but Common Foe
By Meera Balasubramaniam and James E. Galvin
From:  Dana.org
October 02, 2013

If you pick up on items of interest to you, please share! News about this article was recently posted to an LBD-related online support group.

Robin

Recently I purchased a book by Eric Ahlskog, MD, PhD, a well-regarded movement disorder specialist at Mayo Rochester.  The book title is “Dementia with Lewy Bodies & Parkinson’s Disease Dementia:  Patient, Family, and Clinician Working Together for Better Outcomes.”

I’ll put it in our support group lending library for someone to borrow at the next support group meeting.  By the way, if you are interested in making an in-kind donation of books to the support group, a non-profit organization, let me know.  Our wish list is long!

I read three chapters today — one on background, one on symptoms/diagnosis, and one on treatment — and skimmed through the rest.  Based on three chapters, I’d say this is a wonderful book.  It contains the precision of a researcher and clinician, but worded in such a way that we laypeople can understand.  I’ve copied a few excerpts below.

There isn’t anything new in the book for me, but I’ve been reading about Lewy body diseases for quite awhile.  There may be new things for you!

Robin

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Excerpts from:

Dementia with Lewy Bodies & Parkinson’s Disease Dementia:  Patient, Family, and Clinician Working Together for Better Outcomes
by Eric Ahlskog, MD, PhD

Background
“The dementia of both DLB and PDD is due to the Lewy body neurodegenerative process.  However, three other factors also contribute, to varying degrees.  By themselves, these other three factors are not the primary causes of dementia in Lewy conditions but are additive…  One such factor is cerebrovascular disease, which may be…unrecognized; it may also manifest as brain atherosclerosis (hardening of the arteries).  Atherosclerosis of small brain arteries is the reason for leukoaraiosis, which is the white blush present to varying extents on the [MRI] brain scans of older adults.  Treating risk factors for such cerebrovascular disease, especially earlier in life, is wise; however, once dementia is present it may be too late.  Such risk factors include hypertension, diabetes mellitus, elevated cholesterol., smoking, and lack of exercise.”

“A second contributor to dementia, but not a major factor in DLB or PDD, is Alzheimer brain pathology…  Such microscopic changes slowly accumulate with aging in most humans, even those without dementia.  In many older adults they are modest and not sufficient to result in dementia.  However, in a brain already challenged with Lewy neurodegenerative pathology, there is little reserve; a small degree of brain Alzheimer pathology will be additive.  Such changes are noted in many, but not all, with DLB or PDD.”

“Finally, contributing to the dementia of DLB and PDD is normal brain aging.  With passing decades of life our brains shrink, which is very apparent on MRI brain scans in those over age 80 years.  This is primarily due to loss of brain connections as part of the aging process.  Although there is a modest, age-related loss of brain cells (neurons), the primary reason for brain shrinkage is loss of synapses and the connecting neuron circuitry (axon terminals, portion of dendrites).  Fortunately, many older adults without Alzheimer’s or Lewy disease are able to compensate for this age-related brain shrinkage, but it is additive if neurodegenerative disorders are present.”

Why and How Do We Distinguish DLB from PDD?
“PDD starts as Parkinson’s disease, which then progresses to include dementia; those with DLB start out with dementia.  Are these just different ends of a single spectrum?  Are they really the same disorder?  This is an unresolved question.”

“Parkinson’s disease is devoid of intellectual problems when it first develops.  In contrast, cognitive impairment is present at the onset of DLB, sometimes with parkinsonism delayed.  In fact, some people with DLB never experience parkinsonism.”

“How do researchers make the distinction? … An international consensus panel has institute the so-called 1-year rule to separate DLB from PDD. … Obviously, this is a little arbitrary, but such distinctions help researchers clearly define what they are studying.  In the clinic, where clinicians deal with real people and their problems, that distinction is less crucial.”

Fluctuations in Thinking and Alertness
“Unique to these Lewy dementias is the fluctuation of mental clarity.  People with DLB or PDD may be alert and lucid during portions of the day, but inexplicably confused several hours later.  This is a hallmark of DLB and PDD.  Daytime drowsiness may similarly fluctuate like this, although there may be other treatable reasons for sleepiness…  The reason for these fluctuations in mental clarity is unknown.”