When most people think of dementia they probably think of Alzheimer’s disease. Since Alzheimer’s is the most common form of dementia, and one of the biggest risk factors for developing AD is age, new developments to combat the disease are often in the news.
There are, however, other types of dementia that are just as devastating as Alzheimer’s disease and they are not necessarily rare. The dementia we’ll focus on in this article is Lewy body dementia. I frequently hear from spouses or adult children of people who have developed LBD. It saddens me that there’s little news to relate to them about research to combat the disease.
According to the Lewy Body Dementia Association, LBD is highly under-diagnosed, partly because it shares some characteristics with the more common Alzheimer’s disease and partly due to lack of awareness of this different type of dementia. LBD can be confused with Alzheimer’s disease or Parkinson’s disease, and can actually accompany Parkinson’s disease.
What is Lewy body dementia?
LBD is a progressive brain disease. It’s also the second most common cause of neurodegenerative dementia after Alzheimer’s. Lewy body dementia is a ‘spectrum disorder,’ meaning it can occur alone or in combination with Parkinson’s disease (Parkinson’s disease with Lewy bodies), or even co-exist with Alzheimer’s disease.
The LBDA states that LBD accounts for up to 20% of dementia cases in the US. That means that up to 1.3 million cases of LBD are diagnosed in the U.S. alone, with only 30-50 percent of LBD cases being accurately diagnosed, even in dementia centers.
What are some differences between Alzheimer’s and Lewy body dementia?
- In early Alzheimer's, memory loss is prominent, while in LBD memory remains fairly intact. Attention and alertness are reduced in LBD, which can mimic memory problems.
- Problem-solving skills are also highly impaired. Alzheimer's disease is commonly thought to be caused by changes in the brain called plaques and tangles. LBD features the presence of Lewy bodies, which are misfolded alpha-synuclein proteins.
- People with LBD experience changes in movement that can resemble Parkinson's disease, such as slow, stiff movements, changes in gait or posture and tremor. With Alzheimer's disease, movement remains normal until the advanced stages.
- While someone in the advanced stages of Alzheimer's may experience hallucinations, visual hallucinations are common in LBD early in the disorder.
- REM sleep behavior disorder (RBD) is a risk factor for Lewy body dementias, but not for Alzheimer's disease. A person with RBD often physically acts out dreams, which can be frightening, and they sometimes injure themselves or their bed partners. This behavior may begin years, or even decades, before LBD dementia appears.
What dementia symptoms are specific to Lewy body dementia?
- Fluctuating cognition
- Neuroleptic sensitivity (neuroleptics are antipsychotics - medications used to treat hallucinations or other serious mental disorders)
Additional symptoms typical of Lewy body dementia:
- Visual hallucinations (also smell, sound, taste, touch)
- Transient/unexplained unresponsiveness
- Delusions, mood disorders
- Visuospatial impairment (depth perception, object orientation)
- Sleep disturbances, such as acting out vivid nightmares and dreams
- Autonomic dysfunction (blood pressure fluctuations, constipation, incontinence, sexual dysfunction)
What LBD symptoms resemble Alzheimer’s?
- Progressive memory loss
- Changes in mood and behavior
- Decreased judgment and insight
- Loss of initiative
- Disorientation regarding time and place
- Difficulty with language and tasks
What LBD symptoms resemble Parkinson’s?
- Extrapyramidal signs (the extrapyramidal system is a neural network that is part of the motor system that causes involuntary reflexes, movement and coordination)
- Muscle stiffness and rigidity
- Very slow movements, frozen stance
- Balancing difficulties, shuffling gait
- Stooped posture
- Blank facial expression
- Difficulty swallowing, weak voice
- Restless leg syndrome
- Repeated falls, fainting, myoclonus (involuntary twitching of a muscle or a group of muscles)
What are the clinical challenges of managing LBD?
- Antipsychotic drugs may cause worsening of confusion, Parkinsonism, heavy sedation, neuroleptic malignant syndrome.
- Benzodiazepines, anticholinergics, and some surgical anesthetics, antidepressants, and over-the-counter medications may cause sedation, motor impairment or confusion.
Caregiver Burden in Lewy Body Dementia
According to Elizabeth Patrick, Marketing and Communications Manager for the Lewy Body Dementia Association, providing care for someone with LBD can be particularly challenging.
Patrick says, “Lewy body dementia (LBD) is the second leading cause of progressive dementia… Because LBD affects not only cognition, but also movement, LBD caregivers may experience a higher level of burden than family members of Alzheimer’s or Parkinson’s disease patients.”
Loss of independence often occurs early in LBD. People quickly lose the ability to manage their own medications and finances. Driving is also commonly curtailed early in LBD due to visuospatial problems, hallucinations, or fluctuating cognitive abilities.
Caregiver Burden Survey
The Lewy Body Dementia Association (LBDA) conducted an Internet-based Caregiver Burden Survey of family caregivers in order to better understand the impact of caring for a relative with LBD. It was designed to examine a wide range of experiences, including early symptoms, the process and problems of obtaining a diagnosis, on-going care of the person with LBD, and stress on the family.
High levels of burden were reported by LBD caregivers not just because of the time, effort and energy it takes to provide care, but also from increased emotional and financial burdens. Disrupted sleep, social isolation, depression, and decreased health are also common in LBD caregivers.
Support for LBD families is available from a national list of support groups. Caregivers can call Caregiver Link 1-800-LEWYSOS or receive support from the online LBD Forum at www.lbda.org.
Lewy Body Dementia Association at www.lbda.org.