Delirium vs. Dementia Flashcards
What are the differences in delirium vs. dementia in terms of their: Time course?
- Delirium = acute
* Dementia = chronic
What are the differences in delirium vs. dementia in terms of their: Attention?
• Delirium = impaired
Dementia = normal
What are the differences in delirium vs. dementia in terms of their: Level of consciousness?
- Delirium = fluctuating
* Dementia = normal
What are the differences in delirium vs. dementia in terms of their: Memory
- Delirium = poor registration
* Dementia = amnesia
What are the differences in delirium vs. dementia in terms of their: Reversibility
- Delirium = common
* Dementia = uncommon
What are the differences in delirium vs. dementia in terms of their: Toxic and metabolic causes
- Delirium = typical
* Dementia = unusual
What are the differences in delirium vs. dementia in terms of their: Speech and language
- Delirium = inchoherent speech
* Dementia = aphasia
What is the definition of delirium?
- From latin “off the track”
- Rapidly developing disorder of attention characterized by an inability to maintain a coherent line of thought
- Acute confusional state
- Toxic-metabolic encephalopathy
- Incorporates the more rare but visual delirium tremens - to describe the hyperaroused, agitated, hallucinatory state
- MORE COMMON is underaroused, lethargic, somnolent state
What is meant by “clouded dementia”?
- The phenomenon where demented patients more easily and quickly become delierious
- This can reflect poor outcomes in these older, demented patients and contribute to progression of dementia
What are most vulnerable neurons to delirium?
- Chonlinergic, dopaminergic, histaminergic, noradrenergic and serotonergic
- Note NOT GABA or glutamate systems
What is the pathophysiology of delirium?
- Perturbations in the metabolic environment of the brain…and the brain freaks out
- Represents diffuse brain dysfunction related to a disruption of normal brain homeostasis
- The neuronal dysfunction is widespread affecting arousal systems in the brainstem and diencephalon as well as cortical regions
- There is usually an underlying shift in the brain’s environment that causes the delirium, and removal of that cause can often reverse the condition
What psychiatric disorders go on the differential for delirium?
• Schizoprenia and psychotic diseases
○ Main differentiator here is the fluctuations in level of consciousness
• Mania and depression
○ No fluctuation in level of consciousness like there is in delirium though
○ And also there is change in affect usually (not in delirium)
What might cause delirium?
• Anything that would mess with the metabolic environment of the brain • Most often drugs and toxins ○ OTC drugs, recreational drugs, illicit substances ○ Intoxication AND withdrawal • Infectious and inflammatory disease ○ Meningitis ○ Encephalitis ○ CNS vasculitis ○ Systemic infection • Structural lesions ○ TBI, stroke • Seizure disorders
What are the routine laboratory tests for delirium?
• Complete metabolic panel • Complete blood count • Urinalysis • Urinary toxicology screen • Electrocardiogram • Chest radiograph • Image of brain ○ CT or MRI • LP is required if brain infection is suspected • EEG can be helpful for confirmin non-convulsive status epilepticus
What always starts your evaluation of the delirium patient?
History, physical exam, neurologic exam
*not necessarily the mini mental status exam which is usually unrewarding with the confused state of the patient
What is the most important rule of delirium treatment?
• Find the cause, and reverse/treat the cause
• You can enhance normal cognitive function during treatment:
○ Clock and calendar (environmental manipulations)
○ Provision of adequate sleep and restore the sleep-wake cycle
○ Calming medications such as the atypical neuroleptics
What causes dementia (etiology)?
• Reversible (10-20%) and irreversible (80-90%) • Reversible ○ Drugs and toxins ○ Mass lesions ○ Normal pressure hydrocephalus ○ Hypothyroidism ○ Vitamin B12 deficiency ○ Neurosyphilis ○ CNS inflammatory disease (like SLE) ○ Systemic infection/inflammation ○ Severe depression ○ Mild traumatic brain injury • Irreversible ○ Alzheimer ○ Frontotemporal dementia ○ Vascular dementia ○ Huntington ○ Parkinson ○ Lewy body dementia ○ Creutzfeldt-jakob ○ Multiple sclerosis ○ HIV-associated dementia ○ Severe traumatic brain injury
What are the reversible causes of dementia we discussed?
• Reversible (10-20%) and irreversible (80-90%) • Reversible ○ Drugs and toxins ○ Mass lesions ○ Normal pressure hydrocephalus ○ Hypothyroidism ○ Vitamin B12 deficiency ○ Neurosyphilis ○ CNS inflammatory disease (like SLE) ○ Systemic infection/inflammation ○ Severe depression ○ Mild traumatic brain injury
what are the irreversible causes of dementia we discussed?
• Reversible (10-20%) and irreversible (80-90%) • Irreversible ○ Alzheimer ○ Frontotemporal dementia ○ Vascular dementia ○ Huntington ○ Parkinson ○ Lewy body dementia ○ Creutzfeldt-jakob ○ Multiple sclerosis ○ HIV-associated dementia ○ Severe traumatic brain injury
What is the definition of dementia?
• “down from the mind” - latin
• Acquired and persistent impairment in intellectual function with deficits in at least three:
○ Memory
○ Language
○ Visuospatial skills
○ Emotion and personality
○ Complex cognition
• Must interfere with usual social and occupational activities (be actual pathology)
• Need not be either progressive or irreversible by definition, though it largely is
What is the most important objective of the demential work-up?
- Find, if possible, a reversible cause and treat it
* Rare-ish to find, but you need to look for it
What tests/procedures are considered in the dementia work up?
• History and physical exam (neuro, mental status, physical)
• CMP
• CBC
• TSH
• B12
• RPR - rapid plasma reagin - screen for syphilis
• MRI/CT scan
• Only in select cases:
○ HIV, EEG, ESR, antibody for autoimmune dementia, heavy metal screen, angiography and biopsy
What are the two most common cortical dementias?
- These are neurodegenerative dementias
- Alzheimer
- FTD or frontotemporal dementia
What are the clinical features of alzheimer’s disease?
• Know that AD has a defined clinical profile that helps make this dx
• Stage I - amnesia is notable
• Stage II - dementia is obvious
• Stage III - mental and physical incapacity
• MCI - mild cognitive impairment - is associated with age but can convert to true AD (10-15% per year)
○ 1-2% of non-MCI elderly convert
• Most common in older individuals with 5-10% prevalence after 65 and near 40% over 85
What must be present on neuropathology to confirm the AD dx?
- AD is characterized by cerebral atrophy and amyloid plaques and neurofibrillary tangles
- Sufficient plaques and tangles either on brain biopsy or at autopsy
- Brain biopsy is rarely done, the clinical features are pretty telling
- 90% accuracy with probable AD dx (clinical)
What causes AD?
• Largely unknown, but it is a mix of environmental and genetic factors
