Delirium and dementia

Question 1

Delirium vs dementia

Answer 1

• Delirium (acute confusional state, ACS) is almost always due to metabolic problems
• Dementia (AD, lewy body dementia, frontal temporal lobe dementia) can be degenerative, vascular, or metabolic
• Dementia is usually degenerative

Question 2

DSM cirteria for delirium (ACS)

Answer 2

• Disturbance of consciousness w/ reduced ability to focus, sustain, or shift attention
• Develops over a short period of time (acute: hours to days) and tends to fluctuate
• Must not be caused by physiological consequences of a general medical condition

Question 3

ACS cause

Answer 3

• Affects all parts of the behavioral domains
• The cause is usually extrinsic to the brain
• Mostly affects attention and alertness
• Also affects (to some degree) executive function, visual/spatial, language, and episodic memory
• Major disruption to sleep-wake cycle

Question 4

DSM criteria for dementia

Answer 4

• Cognitive impairment to memory and one of the following: aphasia, apraxia (execute learned movements), agnosia (recognize objects), or executive functions
• Must be impairing social or occupational function
• Must be decline from previous level of function
• Must not be due to delirium or depression

Question 5

Causes of dementia

Answer 5

• Cause is usually intrinsic to brain and mostly only affects higher order functioning
• Executive, visual/spatial, language, and episodic memory are all mostly affected
• Its onset is usually insidious, gradually progressive (chronic)
• Pts have clear consciousness, but impaired awareness, orientation, memory, thinking, perception

Question 6

Behaviors in delirium and dementia

Answer 6

• In ACS there is attentional matrix deficit
• In AD there is episodic memory loss
• In lewy body dementia (LBD) there is loss of attention and executive control
• In right hemispheric FTD (behavioral variant) there is loss of emotional salience network
• In left hemispheric FTD (primary progressive aphasia) there is loss of the language network

Question 7

Cognitive network and attentional matrix functioning

Answer 7

• Acts in both bottom up and top down approaches
• Bottom up: reticular activating system maintains visual/spatial, language, and memory
• Top down: frontal, parietal, and limbic domains maintain visual/spatial, language, and memory
• Both are affected in delirium, only top down is affected in dementia

Question 8

Risk factors for delirium

Answer 8

• Age, comorbidities
• Pre-existing cognitive decline, ill physical condition
• Etoh, drug use/withdrawal
• Renal and liver failure

Question 9

Rx of ACS

Answer 9

• Rx the underlying cause of ACS
• Stop anticholinergics, BZDs, opiates
• Can give neuroleptics, a2 agonists
• Do NOT use BZDs

Question 10

Neurodegenerative dementia

Answer 10

• AD: tau neurofibrillary tangles (intracellular) and beta-amyloid plaques (extracellular)
• LBD: lewy bodies (composed of alpha-synuclein, intracellular)
• FTD: both tau protein and TDP43 deposits (cytoplasmic inclusions)
• The oligomers are the toxic elements
• APOE4 gene is a risk factor for AD: involved in cholesterol metabolism, brain metabolism, and clearing toxins from brain

Question 11

Progression of AD

Answer 11

• First Sx is mild cognitive impairment (MCI)
• Tau neurofibrillary tangles develop in hippocampus then spread to multi-modal areas (parietal and frontal lobes)
• Begins w/ memory loss then aphasia and higher executive functions
• Rx: CEIs (donepezil, galantamine) but they only help Sx and don’t stop progression

Question 12

Clinical criteria for LBD

Answer 12

• Dementia and 2 of the following: fluctuating cognition/attention/alertness, recurrent visual hallucinations, parkinsonism motor features
• When it comes to short term memory, giving cues may help someone w/ LBD but will never help someone w/ AD
• Affects the substantia nigra and other parts
• Rx is CEIs as well

Question 13

Frontal temporal lobe dementia (FTD)

Answer 13

• Can be left hemispheric (primary progressive aphasia) or right hemispheric (behavioral variant)
• There is sparing of parietal lobe and hippocampus (these are not spared in AD)
• Can also differentiate btwn FTD and AD by presence/absence of beta-amyloid (both have tau deposits)
• Do not Rx w/ CEI (no cholinergic deficits in FTD)