by Janet Keiser
Lewy Body Dementia Assocation, Inc.
Nearly everyone knows about Alzheimer’s disease (AD), which is the leading cause of dementia in the elderly. Vascular dementia is also widely recognized because it was considered the second most common dementia subtype until recently. We now recognize it as the third most common cause of dementia. But have you ever heard of Lewy body dementia (LBD), what we now believe to be the second most common cause of dementia?
According to autopsy studies, LBD accounts for up to 20-35 percent of dementia cases.1 Unfortunately, Lewy Body Dementia (LBD) is unrecognized by most general practitioners (GP), and patients often find themselves with a diagnosis of AD or Parkinson’s Disease (PD) instead. It is critical for the GP to recognize the symptoms of LBD, as the GP will often be the first medical professional providing treatment, and there are some crucial differences in medication management.
An LBD patient usually presents with symptoms of Parkinsonism or hallucinations, short-term memory loss, and unpredictable personality and cognitive swings. More recently sleep disturbances have been added to the list of diagnostic criteria. While in REM sleep a patient may “act out” their dream; upon awakening the patient can be very confused.2 The patient may be experiencing an odd set of symptoms and find it difficult to articulate what changes are being experienced.
The research conducted to date can help to separate out LBD symptoms from other forms of dementia. Dementia plus two of the following three symptoms indicates a probable diagnosis of LBD:
Other features include falling, loss of balance; a patient may announce, “I’m going upstairs now,” when living in a one-story home. A patient may also fall suddenly, without warning. Fainting spells, transient loss of consciousness, and delusions are also common.
The disease is not necessarily genetic, although having a family member with LBD may slightly increase a person’s risk. Also, LBD strikes more men than women between the ages of 60-804. LBD progresses more rapidly than AD, and symptoms presented can be clues to the stage of the disease. The average time until death from the onset of diagnosis can be anywhere from 2-20 years, with an average prognosis of 5-7 years.
When considering the history of the patient, the specialist will make use of cognitive tests and laboratory work. The tests can be neurological, cognitive and neuropsychological. For example, many physicians will use the Mini-Mental State Examination (MMSE), test language skills and math skills. Fluctuating levels of cognitive ability may make the patient seem quite normal at times, and diagnosis can be a long, frustrating process when different physicians, and even family members, see the same patient in various states of mind. Like AD, only a process of elimination can achieve a diagnosis of LBD. For further clarification, imaging (CT, MRI, PET) is used to view atrophy in the brain, sometimes a indicator of dementia or stroke. Unfortunately, there is no cure for LBD and the disease can only officially be diagnosed by autopsy.
After making a preliminary diagnosis, the GP may make referrals to different specialists, including a neurologist, gerontologist, psychiatrist, nurse practitioner, pharmacologist, social worker, and nutritionist.
Different dementia diseases can overlap: “Dementia with Lewy bodies is present in about 15 and 30 percent of cases diagnosed by the pathologist as Alzheimer's disease. Conversely, of cases showing Lewy-body dementia, 60 to 90 percent also have Alzheimer's pathology. Thus, to a degree, the pathological hallmarks of Alzheimer's disease—plaques, tangles, and the associated synaptic and neuronal loss—are features in the large majority, but definitely not all, of Lewy-body dementia cases…” 3 This overlap of diseases obscures the symptoms, giving patients symptoms of both AD and LBD.5 This is a major contributor to the difficulty in making an accurate diagnosis.6
The LBD patient may need various medications to manage the dementia, unsteady movements with falling, and behavioral changes. Cholinerase inhibitors have been shown to be effective in some patients; in others the medication made no difference. Neuroleptics are often given to patients suffering from hallucinations. Accurate diagnosis is critical because LBD patients may react adversely to neuroleptics; further, studies have shown that these negative reactions may not be reversible.4
As diagnosis is made and treatment options are discussed, a support system must be established. It is important that caregivers be counseled, educated, and given realistic expectations for the future, as the comfort of the patient will be achieved by hands-on care as much as with medication.
Every LBD patient is different and LBD research has a long way to go. In the meantime, there are resources available for caregivers and physicians. The Lewy Body Dementia Association (LBDA) website is http://www.lewybodydementia.org, and includes links to two online LBD caregiver support groups. The Canadian Alzheimer’s Association website is http://www.alzheimer.ca.
Article by Janet Keiser
(edited by Angela Taylor, LBDA; scientific review by Dr. Carol
Lippa, Drexel University, Philadelphia, PA). Janet is a Librarian and medical researcher in San Francisco,
CA, and serves as a volunteer for the LBD Association.
1. Ferman, PhD., Tanis.
Neurology. 1.27.2004
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in Parkinson’s Disease and Dementia with Lewy Bodies.
Boeve, MD, Bradley F. et al. Journal of Geriatric Psychiatry
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Dementia, Dementia with Lewy Bodies, and Frontotemporal
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Digital Knowledge Ventures (DKV) at Columbia University in
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