First Aid: Cognitive Disorders Flashcards
List the 3 main categories of cognitive disorders.
- Dementia
- Delirium
- Amnestic disorders
List the 3 main categories of cognitive disorders.
- Dementia
- Delirium
- Amnestic disorders
What is a perfect score on an MMSE?
30
What is considered dysfunction on an MMSE?
Impairment of memory and other cognitive functions without alteration in the level of consciousness.
Dementia
What percentage of people >80 yo have a severe form of dementia?
20%
What percentage of demented patients get delusions and hallucinations?
30%
What percentage of demented patients have affective symptoms (depression and anxiety)?
40-50%
What are the 3 most common causes of dementia?
- Alzheimer’s disease (50-60%)
- Vascular dementia (10-20%)
- Major depression (pseudodementia)
What percent of demented patients have a treatable and potentially reversible condition?
15%
What is the minimum workup to exclude reversible causes of dementia? (6)
- CBC
- Electrolytes
- TFTs
- VDRL/RPR
- B12 and folate
- Brain CT or MRI
Dementia with stepwise increase in severity + focal neurological signs
Multi-infarct dementia
How do you diagnose multi-infarct dementia?
CT/MRI
Dementia with cogwheel rigidity + resting tremor
Lewy Body Dementia/ Parkinson’s Disease
How do you diagnose Lewy Body Dementia/ Parkinson’s Disease?
clinical
Dementia with ataxia + urinary incontinence + dilated cerebral ventricles
Normal pressure hydrocephalus
How do you diagnose normal pressure hydrocephalus?
CT/MRI
Dementia with obesity + coarse hair + constipation + cold intolerance
Hypothyroidism
How do you diagnose hypothyroidism?
T4, TSH
Dementia with diminished position/vibration sense + megaloblasts on the CBC
Vitamin B12 deficiency
Dementia + tremor + abnormal liver enzymes + Kayser-Fleischer rings
Wilson’s disease
How do you diagnose Wilson’s disease?
Ceruloplasmin
Dementia + diminished position and vibration sense + Argyll-Roberston pupils
Neurosyphilis
What are Argyll-Robertson pupils?
pupils that accommodate and constrict but do not react to light
How do you diagnose neurosyphilis?
CSF FTA-ABS or CSF VDRL
What is the hallmark of delirium?
waxing and waning of consciousness
What are the 2 types of delirium?
Quiet
Agitated
What is used to diagnose delirium?
- Memorial Delirium Assessment Scale
- CAM
What is the treatment for delirium?
- Rule out life-threatening causes
- Treat reversible causes
- Antipsychotics: Quetiapine or Haloperidol PO/IM (not IV unless connected to heart monitor as TdP may occur)
- Avoid napping
- Keep lights on, shades open during day
What are the negatives of using benzodiazepines on a patient with delirium?
- Can cause paradoxical disinhibition
- Respiratory depression
- Increased risk of falls
What is the differential for delirium?
AEIOU TIPS
- Alcohol
- Electrolytes
- Iatrogenic
- Oxygen hypoxia
- Uremia/hepatic encephalopathy
- Trauma
- Infection
- Poisons
- Seizure (post-ictal)
How long does delirium last?
3 days to 2 weeks
Orientation is impaired in delirium or dementia?
both! (dementia patients can sometimes remain oriented)
What type of memory is impaired in delirium?
immediate and recent memory
What type of memory is impaired in dementia?
Recent and remote memory
Hallucinations more commonly occur in delirium or dementia?
delirium (usually visual)
Symptoms are worse at night in delirium or dementia?
delirium
EEG changes (fast waves or generalized slowing) is seen in delirium or dementia?
delirium
What is the most common dementia? What percent?
Alzheimers (80% of all dementias)
What is the incidence of Alzheimer’s disease in people > 85?
25%
What gender more commonly gets Alzheimer’s?
women > men
What is the average life expectancy after diagnosis for an Alzheimer’s patient?
8 years
What percentage of patients with Alzheimer’s have a family history?
40%
What is the clinical hallmark of Alzheimer’s?
gradual progressive decline of cognitive functions, especially memory and language
What is the DSM-IV criteria for Alzheimer’s disease?
Memory impairment plus at least one of the following:
- Aphasia
- Apraxia
- Agnosia
- Diminished executive functioning
What is aphasia?
disorder of language affecting speech and understanding
What is apraxia?
inability to perform purposeful movements
What is agnosia?
inability to interpret sensations correctly
What neurochemical changes are seen in patients with Alzheimer’s disease?
Decreased levels of NE (due to loss of noradrenergic neurons in the locus ceruleus of the brainstem) and of Ach (loss of cholinergic neurons in the basal nucleus of Meynert of the midbrain)
What is the only way to definitively diagnose Alzheimer’s disease?
Pathological examination of the brain at biopsy showing diffuse atrophy with enlarged ventricles and flattened sulci
What are the microscopic changes seen in the brain of an Alzheimer’s patient?
- Senile plaques
- Neurofibrillary tangles (dysfunctional ER within neurons)
- Neuronal and synaptic loss
What are senile plaques composed of?
amyloid protein
What are neurofibrillary tangles composed of?
Tau proteins
In what other settings do you see senile plaques and neurofibrillary tangles?
- Down’s syndrome
- Normal aging
What 2 classes of drugs are used to treat Alzheimer’s disease?
- NMDA receptor antagonist
- Cholinesterase inhibitors
What is the NMDA receptor agonist used to treat Alzheimer’s disease?
Memantine
What are the cholinesterase inhibitors to help slow progression of Alzheimer’s disease?
Tacrine (Cognex)
Donepezil (Aricept)
Rivastigmine (Exelon)
What percentage of patients experience a transient improvement in symptoms on cholinesterase inhibitors?
25%
What is the cause of vascular dementia?
Microvascular disease in the brain that produces multiple small infarcts (substantial infarct burden builds up before dementia develops)
What is the disease manifestations of vascular dementia?
same as Alzheimer’s
How might you differentiate between vascular dementia and Alzheimer’s disease?
- Vascular dementia has a stepwise loss of function as the microinfarcts build up
- Focal neurological symptoms (hyperreflexia or paresthesias)
- More abrupt onset
- Greater preservation of personality
What is mild cognitive impairment (MCI)?
normal daily function but abnormal memory for age (most progress to Alzheimer’s disease)
How do you diagnose vascular dementia?
MRI
Which cause of dementia has personality and behavioral changes that are more prominent early in disease (compared with Alzheimer’s disease)?
Pick’s Disease (Frontotemporal Dementia)
What is the gross pathology of a brain with Pick’s disease?
atrophy of frontotemporal lobes
What is the microscopic pathology of Pick’s disease?
Intraneuronal inclusion bodies (not necessary for diagnosis)
How long after diagnosis do patients with Huntington’s Disease live?
around 15
When is the onset of HD?
35-50 yo
What are the hallmarks of HD?
- Progressive dementia
- Bizarre choreiform movements
- Muscular hypertonicity
- Depression and psychosis are very common
What is the cause of HD?
trinucleotide repeat on short arm of chromosome 4
What part of the brain is affected in HD?
Basal ganglia
How can you diagnose HD?
- MRI (caudate atrophy; some cortical atrophy)
- Genetic testing
List the cortical dementias.
Alzheimer’s
Pick’s
CJD
List the subcortical Dementias
Huntington’s
Parkinson’s
NPH
Multi-infarct dementia
Which type of dementia has a decline in intellectual functioning?
Cortical
Which type of dementia have more prominent affective and movement symptoms?
Subcortical
What part of the brain is affected in Parkinson’s disease?
Prominent neuronal loss in the substantia nigra
What is the normal role of the substantia nigra?
provides dopamine to the basal ganglia
What percentage of patient with Parkinson’s disease develop dementia?
around 30%
What are the clinical manifestations of Parkinson’s disease?
- Bradykinesia
- Cogwheel rigidity
- Resting tremor (pill-rolling)
- Mask-like facial expression
- Shuffling gait
- Dysarthria (abnormal speech)
What percent of patients with PD have depression?
50%
What causes PD?
- Idiopathic
- Traumatic
- Drug- or toxin- induced
- Encephalitic
- Familial (rare)
What are the treatment options for PD?
- Replace DA
- Stimulate DA receptors
- Inhibit DA breakdown
- Anticholinergics
What is levodopa?
Chemical that can cross BBB and is degraded to DA by dopadecarboxylase
What is carbidopa?
peripheral dopadecarboxylase inhibitor that prevents levodopa conversion to DA before it can reach the brain
What is the role of amantadine in PD?
emancipates DA
What is the role of anticholinergics in PD?
helps relieve tremor
What is an example of a DA agonist used in PD?
bromocriptine
What is selegiline and why is it used in PD?
MAO-B inhibitor that inhibits breakdown of DA
What are the treatment options for PD patients no longer responsive to pharmacotherapy?
Thalamotomy
Pallidotomy
(surgery)
WHat is the name of the rapidly progressive, degenerative disease of the CNS caused by a prion.
Creutzfeldt-Jakob Disease
What type of transplant is associated with CJD?
corneal
What are the hallmark features of CJD?
- Rapidly progressive dementia 6-12 months after onset of symptoms
- > 90% have myoclonus
- Extrapyramidal signs, ataxia, and LMN signs are also common
What is the typical length of time between exposure and disease onset with CJD?
long latency period
What are prions?
proteinaceous infectious particles that are normally expressed by healthy neurons in the brain
What pathological changes are seen in CJD?
spongiform changes of cerebral cortex
neuronal loss
hypertrophy of glial cells
What does an EEG show in CJD?
periodic sharp waves/spikes
What is needed for a definitive diagnosis of CJD?
pathological demonstration of spongiform changes of brain tissue
What s/s point you toward CJD?
Presence of both rapidly progressive dementia and EEG changes + at least 2 of the following features:
- Myoclonus
- Cortical blindness
- Ataxia, pyramidal signs, extrapyramidal signs
- Muscle atrophy
- Mutism
What reversible form of dementia has large ventricles with increased CSF pressure?
Normal pressure hydrocephalus
What is the classic triad for normal pressure hydrocephalus?
- Wobbly (gait disturbance)
- Wet (urinary incontinence)
- Wild (dementia with mild and insidious onset)
How do you treat normal pressure hydrocephalus?
Relieve increased pressure with a shunt
What is an acute disorder of cognition related to impairment of cerebral metabolism?
delirium
List some causes of delirium.
I'M DELIRIOUS Impaired delivery (of substrates to brain) Metabolic Drugs Endocrinopathy Liver disease Infrastructure (structural disease of neurons) Renal failure Infection Oxygen UTI Sensory deprivation
Delirium + hemiparesis or other focal neuro signs/symtpoms
CVA or Mass Lesion
How do you diagnose CVA or mass lesion?
Brain CT/MRI
Delirium + elevated BP + papilledema
Hypertensive encephalopathy
How do you diagnose hypertensive encephalopathy?
Brain CT/MRI
Delirium + dilated pupils + tachycardia
Drug intoxication
Delirium + fever + nuchal rigidity + photophobia
Meningitis
How do you diagnose meningitis?
lumbar puncture
Delirium + tachycardia + tremor + thyromegaly
Thyrotoxicosis
How do you diagnose thyrotoxicosis?
T4, TSH
What is the work-up for treating delirious patinets?
FEUD
- Fluids/nutrition
- Environment
- Underlying cause
- Drug withdrawal
What drug should be avoided in delirious patients due to likelihood to exacerbate delirium?
benzodiazepines
Which disorder ALWAYS occur secondary to an underlying medical condition and cause impairment of memory without other cognitive problems or altered consciousness?
amnestic disorders
What are some causes of amnestic disorders?
- Hypoglycemia
- Systemic illness (thiamine deficiency)
- Hypoxia
- Head trauma
- Brain tumor
- CVA
- Seizures
- MS
- Herpes simplex encephalitis
- Substance use
Which causes of amnestic disorders lead to a transient illness with full recovery?
- Seizures
- Medication induced
Which causes of amnestic disorder can possibly lead to permanent impairment?
Hypoxia
Head trauma
Herpes simplex encephalitis
CVA