Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0752347 (Dementia with Lewy bodies)
 1,653 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Neurocardiovascular instability (NCVI, neurally mediated disorders causing hypotension with or without bradycardia) represents abnormal neural control of the cardiovascular system and presents as dizziness, syncope, or falls. The mechanisms underpinning NCVI are incompletely understood. The three most common disorders are carotid sinus syndrome (CSS), orthostatic hypotension (OH), and vasovagal syndrome (VVS): CSS, cardioinhibition > 3 s and/or vasodepressor response > or = 50 mmHg drop in systolic pressure during carotid sinus stimulation; OH: fall in systolic blood pressure > 20 mmHg during standing; VVS: cardioinhibition > 3 s and/or vasodepressor response > 50 mmHg during prolonged head-up tilting. In fallers with cognitive impairment or dementia, the prevalence of NCVI is 70%. Multifactorial interventions, including treatment of NCVI, significantly reduce falls and syncope. The predominant components of NCVI in fallers with cognitive impairment and dementia are CSS and OH. In Lewy body and Alzheimer's dementia, the prevalence of NCVI is up to 60%, again predominantly CSS and OH. The prevalence of cardioinhibitory carotid sinus hypersensitivity is particularly high in Lewy body dementia-41% compared with 12% in Alzheimer's disease and 3% in case controls. In addition, patients with Lewy body dementia have greater heart rate slowing (>2 s) and falls in systolic blood pressure (>20 mmHg) than those with Alzheimer's disease or controls during carotid sinus stimulation. The extent of deep white matter hyperintensities on MRI correlates with systolic fall during carotid sinus stimulation (R = 0.58; p < 0.005), suggesting a possible causal association between bradyarrhythmia-induced hypotension and microvascular pathology. NCVI is common in patients with dementia and may be a reversible cause of falls and syncope. Repeated hypotensive episodes may exaggerate cognitive decline in these patients.
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PMID:Neurocardiovascular instability in cognitive impairment and dementia. 1248 Jul 51

Dementia with Lewy bodies (DLB) is a neurodegenerative condition that results in loss of mesopontine cholinergic neurons and sympathetic deinnervation. Although acetylcholinesterase inhibitors have been shown to improve cognitive and behavioral deficits in DLB, these patients may be more susceptible to bradyarrhythmic side effects from this class of drugs due to the autonomic insufficiency associated with the disease. We present a patient who experienced a dose-dependent, symptomatic sinus bradyarrhythmia with donepezil doses at and greater than 5 mg. Owing to underlying autonomic dysfunction, patients with DLB may be at increased risk of bradyarrhythmia resulting from treatment with acetylcholinesterase inhibitors.
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PMID:Donepezil-associated bradyarrhythmia in a patient with dementia with Lewy bodies (DLB). 2050 40