Major Neurocognitive Disorders Due to Lewy Body Disease

Major neurocognitive disorder due to Lewy body disease, or dementia with Lewy bodies (DLB), is a neurodegenerative disease with cognitive, motor, and neuropsychiatric symptoms. It ranks as one of the most common causes of major neurocognitive disorder, behind Alzheimer’s disease (AD). DLB is characterized by a heterogenous clinical presentation with nonspecific structural changes to the brain, which can make accurate diagnosis and treatment a challenge. The core clinical features that classically distinguish DLB from other neurocognitive disorders include prominent visual hallucinations, rapid eye movement (REM) behavior disorder, parkinsonism, and profoundly altered sensorium. The cytoplasmic inclusion body made of alpha-synuclein is a hallmark histologic feature, although there are multiple biomarkers that can aid in the diagnostic process. Non-pharmacologic treatment options are essential to patient care, as highlighted by the limitations in medications both in their efficacy and risk of adverse effects. Pharmacologic treatment of DLB is primarily driven by a combination of psychotropic medication classes (e.g., antidepressants, antipsychotics) and cognitive enhancing medications (e.g., acetylcholinesterase inhibitors). In this chapter, we will be reviewing the literature on the diagnosis and treatment of DLB, as well as providing context for the ongoing discussions surrounding this complex phenomenon.