Lewy body dementias

Lewy body dementias are a group of progressive brain disorders characterized by the presence of Lewy bodies, abnormal aggregates of protein that develop inside nerve cells, leading to changes in thinking, movement, behavior, and mood. The two most common types are Dementia with Lewy Bodies (DLB) and Parkinson's Disease Dementia (PDD). These conditions share similar features, have similar causes, and are believed to belong to a spectrum of Lewy body diseases that also includes Parkinson's disease. Lewy body dementias are the third most common cause of dementia after Alzheimer's disease and vascular dementia, accounting for up to 20% of dementia cases globally. Despite this, they are often misdiagnosed, underscoring the need for better awareness and understanding of these conditions among healthcare professionals and the general public.

Etiology and Pathogenesis

The exact cause of Lewy body dementias is unknown, but they are characterized by the accumulation of Lewy bodies in the brain. These are spherical structures that develop within nerve cells and are composed of a protein called alpha-synuclein. They are believed to disrupt the normal functioning of neurons, leading to the symptoms of DLB and PDD.

Clinical Features and Diagnosis

Both DLB and PDD share a number of features, including cognitive impairment, fluctuations in attention and alertness, recurrent visual hallucinations, and motor symptoms associated with Parkinson's disease, such as rigidity, bradykinesia, and tremor. However, the timing of these symptoms differs between the two conditions. In DLB, cognitive symptoms appear before or concurrently with motor symptoms, while in PDD, motor symptoms precede cognitive symptoms by at least a year.

Treatment

While there is currently no cure for Lewy body dementias, treatments are available to manage symptoms. These include medications to help manage cognitive symptoms, motor symptoms, and psychiatric symptoms such as hallucinations and depression.

Research

Research into Lewy body dementias is ongoing, with scientists exploring the genetic and environmental factors that may contribute to the development of these diseases, as well as potential new treatments.

See Also

• Dementia
• Parkinson's disease
• Alpha-synuclein
• Neurodegenerative disorders

References

• 1. McKeith IG, Boeve BF, Dickson DW, et al. (2017). Diagnosis and management of dementia with Lewy bodies: Fourth consensus report of the DLB Consortium. Neurology. 89(1):88-100. doi:10.1212/WNL.0000000000004058
• 2. Aarsland, D., Creese, B., Politis, M., Chaudhuri, K. R., Ffytche, D. H., Weintraub, D., & Ballard, C. (2017). Cognitive decline in Parkinson disease. Nature Reviews Neurology, 13(4), 217–231. https://doi.org/10.1038/nrneurol.2017.27

Lewy body dementias Resources
Latest articles Most recent articles Ongoing trials	Wikipedia