Delirium and Dementia

Question 1

What is the definition of delirium?

Answer 1

A rapidly developing disorder of attention characterized by an inability to maintain a coherent line of thought. Also known as an acute confusional state.

Question 2

What are the contrasting features of delirium and dementia?

Answer 2

Delirium:
Acute disorder
Fluctuating level of consciousness
Impaired attention
Incoherent speech
Toxic and metabolic causes usually found
Typically reversible 

Dementia:
Chronic disorder
Normal level of consciousness
Normal attention
Aphasia
Toxic and metabolic causes usually not found
Typically irreversible

Question 3

What is the more common form of delirium?

Answer 3

Hypoaroused: lethargy and somnolence

Less common- hyperaroused: agitation and restlessness (Delirium tremens from alcohol withdrawal)

Question 4

What is the prevalence of delirium in hospitalized patients?

Answer 4

10-60% in elderly, 60-80% in ICU
About half of all hospitalized older people, and a majority of intensive care unit patients develop delirium, and the syndrome predicts a worse outcome.

Question 5

What is the pathophysiological cause of delirium

Answer 5

Delirium represents diffuse brain dysfunction related to a disruption of normal brain homeostasis. Neuronal dysfunction is widespread, affecting arousal systems in the brainstem and diencephalon as well as cortical regions, but the most vulnerable neurons are thought to
be those involved in cholinergic, dopaminergic, histaminergic, noradrenergic, and serotonergic neurotransmission.

Question 6

What are the common causes of delirium

Answer 6

drugs and toxins (intoxication or withdrawal), metabolic disorders, infection/inflammation, structural lesions, seizure disorders

Question 7

What can be done for delirium?

Answer 7

Withdraw agitating factors, manipulate environment, provide adequate sleep (trazodone, zolpidem QHS), Drugs for agitation (Atypical antipsychotics or benzodiazepines PRN- always at lowest possible dose)

Question 8

What is Dementia?

Answer 8

Acquired and persistent impairment of intellectual function or cognition in at least three domains, sufficient in severity to interfere with social and occupational function.

Question 9

What is the most common cause of dementia?

Answer 9

Alzheimer’s disease ~5million in US

Question 10

What causes dementia?

Answer 10

Reversible: drugs and toxins, mass lesions, normal pressure hydrocephalus, systemic illness, Inflammatory diseases (neurosyphilis, SLE), depression, mild traumatic brain injury
Irreversible (80-90%): Alzheimer’s, frontotemporal lobar degeneration, vascular dementia, Lewy Body, Parkinson’s, Huntington’s, HIV assoctiated, moderate and severe traumatic brain injury

Question 11

Evaluation of Dementia?

Answer 11

History and physical examination (general, neurologic, mental status)
CMP, CBC, TSH, B12, RPR
MRI or CT scan of the brain
In selected cases: neuropsychological testing, lumbar puncture, EEG, HIV, ESR, antibodies for autoimmune dementia, ceruloplasmin for Wilson’s Disease, heavy metal screening, genetic testing, cerebral angiography, brain biopsy

Question 12

How can Dementia be classified?

Answer 12

By site of involvement:
cortical- Alzheimer's
subcortical- Parkinson's
White matter- Binswanger's 
Mixed- multiple infarcts

Question 13

What is necessary to be found for a definitive diagnosis of Alzheimer’s?

Answer 13

neuritic plaques and neurofibrillary tangles in neocortex and hippocampus

Question 14

How long do people survive after onset of AD?

Answer 14

6-12 years

Question 15

What are the symptoms of the first stage of AD?

Answer 15

1-3 years- initial amnesia, mild anomia, apathy

Question 16

What are the symptoms of the second stage of AD?

Answer 16

2-10 years- marked amnesia, fluent aphasia, visuospatial dysfunction, anosognosia, neuropsychotic features.

Question 17

What are the symptoms of the third stage of AD?

Answer 17

8-12 years- severe dementia, global aphasia or mutism, incontinence

Question 18

What is Mild cognitive impairment?

Answer 18

Memory complaint, preferably corroborated by an informant
Objective evidence of memory impairment for age and education
Largely normal general cognitive function
Essentially intact daily living activities
No dementia
More likely to develop AD

Question 19

What are the gross findings in AD?

Answer 19

Cerebral atrophy, cortical neuronal and synaptic loss, mostly limbic and association cortices (higher function)

Question 20

What are the causes of AD?

Answer 20

Unknown, but htn, diabetes, and TBI are implicated

Question 21

What are the genetic associations with AD?

Answer 21

Trisomy 21, PSEN-1, PSEN-2, APOE

Question 22

What is frontotemporal dementia

Answer 22

Cortical dementia that selectively affects frontal and temporal lobes (hippocampus is spared until late in disease state). Behavioral disorder before memory loss. Disinhibition and apathy

Question 23

What is Parkinson’s dz?

Answer 23

Loss of dopaminergic cell n the substantia nigra.

Question 24

What is huntington’s dz?

Answer 24

Autosomal Dominant. Early personality changes with dementia and chorea

Question 25

What is Binswanger’s disease?

Answer 25

Vascular dementia related to multiple white matter infarcts. MRI is preferred test

Question 26

What is normal pressure hydrocephalus?

Answer 26

Potentially reversible. Can use shunts, but there are often complications.

Question 27

What is multi-infarct dementia?

Answer 27

Combination of strokes lead to progressive dementia

Question 28

What is creutzfeldt-Jakob dz?

Answer 28

Rapid prion disease that leads to dementia, acute confusion, hallucinations, and delusions

Question 29

What is creutzfeldt-Jakob dz?

Answer 29

Rapid prion disease that leads to dementia, acute confusion, hallucinations, and delusions
Use diffusion MRI- shows cortical or deep gray matter hyperintensity

Question 30

What is the treatment for dementia?

Answer 30

INFORMED COUNSELING, avoid benzodiazepines, cholinesterase inhibitors (donepezil, rivastigmine, galantamine), Memantine (NMDA antagonist)
Behavioral measures to treat neuropsychiatric syndromes. Use drugs sparingly.

Question 31

What is the differential diagnosis for delirium?

Answer 31

Dementia, amnesia, and aphasia

schizophrenia, mania, or depression(but usually no fluctuation in level of consciousness)

Question 32

How do you evaluate for delirium?

Answer 32

It is typically difficult to do a mental status exam, so you usually just document ‘confused state’ in the note. Routine lab tests should be done: H&P, CMP, CBC, urinalysis, electrocardiogram, chest radiograph, tox screen, CT or MRI, LP, EEG.