Exam 3: Dementia/Delirium Flashcards
(47 cards)
Define dementia
A general term for the impaired ability to remember, think, or make decisions that interferes with doing everyday activities.
what areas are affected by dementia and delirium?
-2) temporal lobe: Association area: short term memory, equilibrium, emotion
-13) frontal lobe: High mental functions: concentration, planning, judgement, emotional expression, creativity, inhibition
what does the reticular activating system maintain?
– maintains wakefulness
**in dementia and delirium–>RAS is sometimes off kilter
what are neurons? and how do they communicate?
they are functional cells of the CNS that send and receives information, they are supported by glial cells
- long axons synapses with another neuron and communication goes back and forth between neurons along the axons
what are the three types of glial cells? and its functions
-microglial: phagocytes–cells that go through the CNS and check for abnormalities and correct them
-astrocytes: blood vessel support and communication
- oligodenocytes: myelin sheath production
what are irreversible dementia?
- alzheimer
- frontotemporal
- Lewy body
what are most common reversible dementia?
-Alcoholism (chronic)
-Medications: Anticholinergics and antihistamines (typically used inappropriately in older adults)
-Metabolic diseases: Hypothyroidism and hepatic encephalopathy (complication of etoh)
what are the mechanisms of Irreversible degenerative dementia?
- Abnormal proteins that damage neurons and/or neuronal connections leading to neuronal cell death
**the global pathophysiology for dementia of the irreversible type is abnormal protein
molecular mechanism of Alzheimer
- amyloid beta protein
- phosphorylated tau protein
pathology of Alzheimer
amyloid plaques, neurofibrillary tangles, neuronal and synaptic loss in the brain
molecular mechanism of dementia with Lewy bodies
alpha-synuclein
pathology of dementia with Lewy bodies
alpha-synuclein inclusions (Lewy bodies)
molecular mechanism of behavioral variant frontotemporal dementia
microtubule-associated protein tau (MAPT)
pathology of frontotemporal dementia (3)
- tau inclusions
- pick bodies
- neurofibrillary tangles
what are the most common dementias associated with?
Genetic risks exist but the most common dementias are associated with susceptible genes and multifactorial contributions.
Here’s the expression: “The genes load the gun and the environment and lifestyle pull the trigger.” The truly horrific, early onset, causal gene dementias typically involve an autosomal dominant allele and clear familial transmission
manifestations of dementia
classics are insidious onset (core feature) and progressive decline of cognition, memory, and ability to care for self.
insidious onset–>means slow, its gradual, it sort of sneaks up on you
what are the screening test for dementia? (2)
- mini mental status exam
-montreal cognitive assessment
Abnormal proteins associated with Alzheimer disease
i. Beta amyloid plaque: Amyloid precursor protein (APP), a cell wall glycoprotein, is cleaved by enzymes → beta amyloid protein fragment. Fragments aggregate outside the neuron producing amyloid plaque.
ii. Neurofibrillary tau tangles: The axon is composed of microtubules that send signals from one neuron to another. Tau protein makes up the structure of the microtubule. Tau protein structure altered, microtubules disrupted, tau collects inside the neuron.
iii. Results on beta amyloid and tau: Impaired cell to cell communication and eventually cell death.
what is the pathophysiology of alzheimer’s dementia?
Abnormal proteins damage the 1. neuron cell body and 2. Axons. Neuron to neuron signaling and neuron death occurs.
what can occur when more neurons die throughout the brain?
people may express:
- memory loss
- impaired decision making
- language problems
what is used to diagnose Alzheimer?
a. History, physical exam, blood work, genetic testing in people with family history, and memory (MMSE or MOCA)/psychiatric testing to rule out reversible causes of dementia.
b. Diagnostic and Statistical Manual V (DSM-V): Core characteristics insidious onset and gradual decline AND cognitive impairment in two of the following domains:
- MRI: brain atrophy, sulci (furrows) widening, gyri (folds) shrinking and ventricle enlarging
-Positron emitting tomography (PET) using tracers to detect amyloid plaque and neurofibrillary tau tangles. Required to qualify for newer drugs that clear amyloid plaque (Aducanumab (Aduhelm)).
lis the five Diagnostic and Statistical Manual V (DSM-V) domain for dementia
i. Acquiring and remembering new information: short term memory loss (first impairment)–temporal lobe
ii. Reasoning, judgement, and complex thinking–frontal lobe
iii. Visual special perception
iv. Language use and expression
v. Personality or behavior
what area of the brain does Alzheimer affect?
- changes start in the temporal lobe/hippocampus (memory) and progress toe involve the entire cerebral cortex
biomarks for Alzheimers disease (2)
i. Cerebrospinal fluid: Amyloid beta and tau proteins.
ii. Plasma: Still in investigative stage.