Dementia with Lewy Bodies (DLBs) – how it differs from Traditional Dementia in the Elderly

Dementia affects a staggering 24 million people worldwide, and can have a crushing effect on family, friends and finances. Dementia isn’t a single disease, but rather a name for the loss brain function, especially cognitive function, that is associated with a variety of different illnesses. In the elderly, dementia is most commonly caused by Alzheimer’s Disease. The second most common dementia is called Dementia with Lewy Bodies (DLBs). While both these diseases have devastating effects on those suffering from them, they are different in a variety of ways.

Physiological Differences between Dementia with Lewy Bodies (DLBs) and Traditional Dementia

Although both types of dementia are caused by progressive brain damage, each disease process affects the brain in different ways; hence, the reason for the differences in symptoms and disease progression. In Alzheimer’s Disease,
amyloid plaques and neurofibrillary tangles develop in the brain. Amyloid plaques are made up of protein fragments that were not broken down by the body. Neurofibrillary tangles are twisted fibers made up of abnormal tau proteins. Alzheimer’s patients also suffer a loss of acetylcholine, an important neurotransmitter.

In patients with dementia with Lewy bodies, the brain is overtaken by the formation of Lewy bodies. Lewy bodies are made up of alpha-synuclein proteins that have aggregated. Amyloid plaques are typically also present in DLB, but neurofibrillary tangles tend to be absent or significantly less severe. The negative effect on neurotransmitters differs as well. When compared to Alzheimer’s Disease, the deficit in acetylcholine is more severe. Additionally, those afflicted with DLB lose dopamine as well.

Symptomatology of Dementia with Lewy Bodies (DLBs)

The differences between dementia and DLBs is most apparent during the early stages. In traditional dementia, memory loss is most prevalent. Early memory loss manifests itself in lost objects and forgotten conversations. Those afflicted may also experience personality changes and begin to have trouble with everyday tasks. Typically, dementia progresses relatively slowly, with an average of 12 years between diagnosis and death.

Dementia with Lewy bodies (DLBs), on the other hand, causes a decline is cognitive and motor function, and often presents with psychiatric illness as well. Although cognitive symptoms mirror those of Alzheimer’s Disease, those with DLB experience additional symptoms, including muscle stiffness, full-body tremors and hallucinations. The hallucinations are almost always visual, but auditory, olfactory and even tactile hallucinations have been reported. Additionally, DLB progresses far more rapidly, which results in a much shorter life expectancy in comparison to those with Alzheimer’s Disease. The average lifespan after diagnosis is only five to seven years in those with DLB.

Dementia with Lewy Bodies (DLBs) Treatment

Alzheimer’s Disease is treated using a variety of different medications. The early stages are treated with cholinesterase inhibitors. Cholinesterase inhibitors prevent the loss of acetylcholine, which can delay the onset of more serious symptoms. Advanced Alzheimer’s is treated with NMDA antagonists. NMDA antagonists help regulate many of the brain’s chemicals in a way that prevents brain death. Additionally, medications are often used to treat unpleasant symptoms, such as anti-psychotics.

The treatment for Dementia with Lewy Bodies is a lot less defined. Cholinesterase inhibitors have been used with moderate success in treating cognitive decline. Treating motor and psychiatric symptoms is what can prove to be difficult. Many anti-psychotics cause an increase in motor dysfunction and medications commonly used to treat movement disorders can trigger psychosis. So far, using these drugs carefully at low doses seems to be the best option.