Lewy Body Dementia (LBD) is the most common of the four atypical parkinsonisms and exists in two variants: Dementia with Lewy Bodies and Parkinson’s Disease Dementia. Depending on whom you are talking to, LBD is also classified as a non-Alzheimer’s dementia.
Lewy Body Dementia (LBD) is an umbrella term that refers to two diagnoses:
- Dementia with Lewy Bodies (DLB)
- Parkinson’s Disease Dementia (PDD)
The terms DLB and PDD are of primary interest to researchers and less to families and clinicians. Whether someone is diagnosed with DLB or PDD is largely determined by the arbitrary “one-year rule”: if the onset of dementia or psychiatric symptoms is within one-year of parkinsonism, the disorder is called DLB, and if parkinsonism continues for more than one year before the onset of dementia, the disorder is called PDD. Unfortunately, the one-year rule ignores the possibility that parkinsonism may never be part of DLB.
Though the diagnostic criteria for DLB and PDD differ, the associated symptoms are largely the same:
- Dementia: Everyone with LBD must have progressive dementia. Find our definition of dementia here.
- Fluctuating Cognition: This refers to variability–on the basis of a minute, hour, or day–of attention and alertness. Unfortunately there is no consensus in the medical community how fluctuating cognition is objectively measured. This is part of the diagnostic criteria for DLB, but not PDD.
- Visual Hallucinations: In DLB, usually hallucinations are complex and recur. Note that hallucinations are different from delusions, which can also occur in LBD. A hallucination is the where an individual sees something that is not there – often children or animals. A delusion is where there is an entire story and emotional response to something that isn’t real such as thinking the house is on fire, thinking a family member is an “imposter,” or believing a spouse is unfaithful.
- Parkinsonism: This term includes rigidity, bradykinesia (slow movements), tremor, and postural instability. If someone has a Parkinson’s Disease diagnosis, by definition the person has parkinsonism. Find our definition of parkinsonism here.
Other important symptoms that are suggestive of LBD include:
- Rapid Eye Movement (REM) behavior disorder (RBD), a sleep disorder
- Extreme sensitivity to antipsychotic medication (also called neuroleptics)
- Low dopamine transporter (DaT) uptake in the basal ganglia as demonstrated by SPECT or PET scans
Note: these symptoms are for what we might refer to as “pure” LBD. In most brain bank studies, those with Lewy Body Dementia also tend to have Alzheimer’s pathology, vascular pathology, or other co-occurring pathologies.
What about memory problems? Note that many people with DLB receive a high score on the Mini-Mental Status Exam (MMSE) so that test is often not relevant in DLB. Those with PDD may have more memory impairment than those with DLB. It could be that if memory problems are present, Alzheimer’s pathology is to blame.
Pharmacological treatment of LBD is complex given how sensitive many people are to all kinds of medications.
Generally those with LBD are prescribed Alzheimer’s medications as a first-line treatment for dementia and hallucinations. Current Alzheimer’s medications include donepezil, rivastigmine, galantamine, memantine, and memantine/donepezil (combination). Rivastigmine is the only FDA-approved medication for treating dementia in Parkinson’s Disease.
There can be a tricky balancing act with Parkinson’s medications as a treatment for parkinsonism symptoms. Parkinson’s medications can cause hallucinations and delusions, yet many with LBD are extremely rigid without PD medications.
If hallucinations are frightening or if there are delusions, often atypical antipsychotics are prescribed. Many LBD specialists prefer clozapine or quetiapine. Note that there is an FDA black-box warning on all antipsychotic medications for those with dementia. That said, many in our local support group find these medications to be life-savers. In May 2016, the FDA approved a new medication for psychosis (hallucinations and delusions) in PDD.
LBD experts warn against taking anticholinergic medications (such as many bladder/incontinence medications) and typical antipsychotics (such as haloperidol). Also, given the risks of falls, experts encourage caution for all medications, especially those that can cause sedation (i.e. other-the-counter cold or allergy medications, sl eep aids, cough syrups). We always recommend that you consult your physician prior to administering any medication other than what has been prescribed.
Go-To Organizations for LBD Education
A handful of organizations consistently deliver quality information about LBD. Click the link for each organization to review their web sites:
|Organization Name||Country||Focus||Web Address|
|Lewy Body Dementia Association||USA||Information, awareness||www.lbda.org|
|Alzheimer’s Association||USA||Research, information||DLB: www.alz.org/dementia/dementia-with-lewy-bodies-symptoms.asp|
Brain Support Network continually reviews most of the resources available on LBD. In our opinion, these web pages, documents, and videos are the most helpful resources for families:
Facts about Lewy Body Dementias
This eight-panel pamphlet from the Lewy Body Dementia Association provides an excellent introduction to LBD.
Treatment of and Research on Dementia with Lewy Bodies
This helpful update on DLB was given by Dr. Geoff Kerchner, a behavioral neurologist. This October 2012 Stanford University (SF Bay Area) event was recorded, and the video available online. A DVD is available through CurePSP (sponsor of recording) or Brain Support Network (one of the organizers).
Many Faces of Lewy Body Dementia
This January 2007 family conference at the Coral Springs Medical Center in Florida was recorded. The presentations by psychiatrist Dr. Jonathan Stewart and neurologist Dr. Jay Van Gerpen are excellent.
LBDA’s Youtube Channel: “Ask the Experts”
The Lewy Body Dementia Association’s Youtube channel delivers videos on a variety of topics presented by leading experts on Lewy Body Dementia.
New Insights Into Lewy Body Dementias
This one-hour October 2011 LBDA webinar features Dr. James Galvin, one of the US’s top experts on LBD. He reviews the diagnostic criteria for both DLB and PDD. And he shares treatment options.
Parkinson’s Disease: Mind, Mood & Memory
This excellent 100-page publication from the National Parkinson Foundation has a terrific chapter on Dementia with Lewy Bodies.
Dementia with Lewy Bodies and Parkinson’s Disease Dementia: Patient, Family, and Clinician Working Together for Better Outcomes
This very useful guidebook by Dr. J. Eric Ahlskog, a neurologist with years of LBD experience, is written for the lay audience. Published in September 2013.
Life in the Balance: A Physician’s Memoir of Life, Love and Loss with Parkinson’s Disease and Dementia
This memoir by Thomas Graboys, MD and Peter Zheutlin, was published in 2008. Many caregivers in our local support group have read aloud parts of this book with their family member with LBD.
UCSF Memory & Aging Center Overview of Lewy Body Dementias
This webpage provides an overview of both DLB and PDD – causes, symptoms, diagnosis, progression, and treatment.
Alzheimer’s Association Overview of Dementia with Lewy Bodies
This straightforward explanation of DLB symptoms, diagnosis, causes, and treatments includes a list of key differences between Alzheimer’s and DLB.
10 Things You Should Know About LBD
This short publication of the Lewy Body Dementia Association provides key facts and an overview of symptoms. Available online only.
Lewy Body Dementia: Information for Patients, Families, and Professionals
This 40-page booklet was published in September 2013 by the National Institute on Aging. It describes the main symptoms of Dementia with Lewy Bodies and Parkinson’s Disease Dementia. Available online or request a copy be mailed.
Resources for the newly-diagnosed person or his/her family:
An Introduction to Lewy Body Dementia
This publication of the Lewy Body Dementia Association is for people newly diagnosed with LBD and those still seeking answers. Available online.
LBD Diagnostic Criteria
Lewy Body Dementia (LBD) is an umbrella term that refers to two different diagnoses: Dementia with Lewy Bodies (DLB) and Parkinson’s Disease Dementia (PDD).
Each of these two disorders is characterized by sets of symptoms. Symptoms fit into one of the following five categories. They are:
- Required: must be present
- Core: is almost always present
- Suggestive: is often present
- Cautionary: generally should not be present
- Exclusionary: cannot be present
The diagnosis of either disease depends on the symptoms present. There are three classes of diagnosis:
- Definitive (autopsy confirmed)
Because various disorders (and sub-disorders) have been identified and characterized at different times by different researchers, this framework is not universally used to define disorder symptoms and diagnostic criteria.
The two sets of diagnostic criteria are for what we might refer to as “pure” DLB or “pure” PDD. In most brain bank studies, those with Lewy Body Dementia also tend to have Alzheimer’s pathology, vascular pathology, or other co-occurring pathologies. The diagnostic criteria cannot account for “mixed dementia,” where more than one type of dementia occur simultaneously.
It is technically inaccurate to say that someone has both Parkinson’s Disease and Lewy Body Dementia or that someone has “Parkinson’s Disease with Lewy Bodies.” The most common Lewy body disease is Parkinson’s Disease. In terms of brain pathology, the key difference between Parkinson’s Disease and Dementia with Lewy Bodies / Parkinson’s Disease with Dementia is where in the brain the Lewy bodies are to be found. In PD, Lewy bodies are in the brainstem. In DLB or PDD, Lewy bodies are diffuse throughout the cortex or in a transitional stage between the brainstem and the cortex.
Symptoms and Diagnostic Criteria for Dementia with Lewy Bodies (DLB)
The symptoms and diagnostic criteria for Dementia with Lewy Bodies (DLB) are different than those for Parkinson’s Disease Dementia (PDD). Here we cover DLB.
The source of these criteria is Diagnosis and Management of Dementia with Lewy Bodies: Third Report of the DLB Consortium, McKeith et al, Neurology, December 2005. While only the abstract is free, the full article is available for purchase.
|Required Symptoms||Core Symptoms||Suggestive Symptoms|
|Definitive Diagnosis of DLB||Probable Diagnosis of DLB||Possible Diagnosis of DLB|
Symptoms and Diagnostic Criteria for Parkinson’s Disease Dementia (PDD)
The symptoms and diagnostic criteria for Parkinson’s Disease Dementia (PDD) are different than those for Dementia with Lewy Bodies (DLB). Here we cover PDD.
The source is Clinical diagnostic criteria for dementia associated with Parkinson’s disease, Emre, et al, Movement Disorders, 2007 September 15; 22(12):1689-707. This article assigns symptoms to “Groups”. We’ve repeated the Group classification here, but have assigned a descriptive name to the assemblage, as well.
|Required Symptoms for PDD (“Group I”)|
|Core Symptoms for PDD in Cognitive Domains (“Group II”)||Core Symptoms for PDD in Behavioral Domains (“Group II”)|
|Cautionary Symptoms for PDD (“Group III”)||Exclusionary Symptoms for PDD |
|Definitive Diagnosis of PDD||Probable Diagnosis of PDD||Possible Diagnosis of PDD|