Cognitive Disorders Flashcards
Define delirium.
waxing and waning change in a patient’s level of consciousness (can also be referred to as encephalopathy)
What percent of medically admitted patients exhibit delirium?
10-30%
What are some risk factors for the development of delirium?
advanced age preexisting brain damage prior history of delirium alcohol dependence diabetes cancer sensory impairment or blindness malnutrition male gender
What is the most common finding in delirium?
impairment in recent mamory
What are the diagnostic criteria for delirium?
- disturbance of consciousness w/ reduced ability to focus, sustain, or shift attention
- a change in cognitive or the development of a perceptual disturbance that is not better accounted for by a preexisting, established or evolving dementia
- the disturbance develops over a SHORT period of time (usually hours to days) and tends to fluctuate during the course of the day
If a patient has delerium with hemiparesis or other focal neurological symptoms, think…
CVA or mass lesion and get a brain CT or MRI
If a patient has delirium with elevated blood pressure and papilledema, think….
hypertensive encephalopathy and get a brain CT or MRI
If a patient has delirium with dilated pupils and tachycardia, think….
drug intoxication and get a UDS
If a patient has delirium with fever, nuchal rigidity and photophobia, think….
meningitis and get an LP
If a patient has deliurium, tachycardia, tremor and thyromegaly, think…..
thyrotoxicosis and get a TSH and free T4
Describe the treatment of delirium.
- rule out life-threatening causes
- treat the underlying condition
- supportive care with hydration and nutrition
- one-on-one nursing
- try to correct sleep cycle
- psychotropics for symptomatic relief (antipsychotics like haloperidol)
What psychotropic medication should be avoided in delirium?
benzodiazepines (unless it’s secondary to alcohol or benzo withdrawal) because they have been found to cause/prolong delirium
What is the prevalence of dementia at 60 years? 90 years?
1.5% at 60
40% at 90
(doubles every 5 years)
What is the most common type of dementia? Second most common?
- Alzheimer’s
2. Vascular
If there is a dementia with stepwise increase in severity and focal neurological signs, think….
multi-infarct dementia and get a CT/MRI
If there is dementia with rigidity and a resting tremor, thing…
parkinson disease or lewy body dementia
If there is dementia with gait apraxia, urinary incontinence and dilated cerebral ventricles, think….
normal rpessure hydrocephalus and get a CT/MRI.
If there is dementia with obesity, coarse hair, constipation and cold intolerance, think…
hypothyroidism and get a T4 and TSH
If there is dementia with diminished position and vibration sense with megaloblast on CBC, think…
B12 deficiency
If there is a dementia with tremor, abnormal LFTs and Kayser-Fleischer rings, think….
Wilson disease and check a ceruloplasmin
If there is dementia with diminished position and vibration sense with an afferent pupillary response defect, think….
neurosyphilis and check a CSF FTA-ABS of CSF VDRL
What should a workup for reversible causes of dementia include?
CBC Electrolytes TFTs VDRL/RPR B12 Folate Brain CT or MRI
What are the DSM criteria for dementia?
- development of multiple cognitive deficits manifested by both memory impairment and 1+ of the following:
- aphasia
- agnosia
- apraxia
- disturbance in executive functioning
must cause significant impairment in social or occupational functioning and represent a decline from a previous level of functioning
not exclusively in the course of a delirium
What is the average length of time between diagnosis and death in Alzheimer’s disease?
10 yrs
What are some genes associated with Alzheimer’s?
presenelin 1
presenelin 2
amyloid precursor protein (APP)
apolipoprotein e4 (homozygotes have a 50-90% chance of developing dementia by 85, heterozygotes with 45% change, wildtype with 20% chance)
What are some postmortem gross and micropathology findings in alzheimer’s?
grossly diffuse atrophy with enlarged ventricles and flattened sulci
microscopic with senile plaques and neurofibrillary tangles
Which correlate with severity of dementia: the plaques or the tangles?
plaques
What two general drug classes are used to slow the progression of alzheimer’s down?
cholinesterase inhibitors (donepezil, tacrine, rivastigmine, galantamine)
NMDA antagonists (memantine)
Lewy bodies are pathologic accumulations of what?
alpha-synuclein
Describe some features of lewy body dementia.
waxing and waning of cognition visual hallucinations are very common paranoid delusions common parkinsonism is a core feature REM sleep behavior disorder is common
What is the difference between lewy body dementia and parkinson disease dementia?
It’s all about timing
if the dementia presents within 12 months of the parkinsonism, it’s lewy body dementia
if the dementia presents more than 12 months after the parkinsomism, it’s parkinson disease dementia
What are the pharmacological options for lewy body dementia?
cholinesterase inhibitors psychostimulants levodopa/carbiopa dopamine agonists clonazepam for the REM sleep behavior disorder
What is the typical age of onset for frontotemporal dementia (pick disease)?
45-65
Approximately 20-30% of cases of FTD are familial and associated with what genes?
progranulin or MAPT gene
Describe some features of FTD.
profound changes in personality and social conduct
disinhibited verbal, physical or sexual behavior
echolalia, overeating, oral exploration of inanimate objects
lack of emotional warmth, empathy or sympathy
poor insight about behavioral alterations
cognitive deficits in attention, abstraction, planning and problem solving
memory, language (unless they have the language variant) and spatial function are well preserved
What would you expect to see on gross pathology and microscopic pathology in FTD?
gross: marked atrophy of the frontal and temporal lobes
Micro: neuronal loss, microvacuolization and astrocytic gliosis in cortical layer II
What is HIV-associated dementia probably caused by?
infections due to neutropenia + the direct effects of the virus on cells
Can HIV-associated dementia improve with HAART?
yes - it usually improves with a decreased viral load
When in the disease course of Huntington’s disease does the dementia typically present?
usually within 1 year before or after the chorea
What percentage of patients with parkinson’s disease will develop dementia?
30-40%
How do you diagnose CJC?
definitive diagnosis requires pathological demonstration of spongiform changes of brain tissue
probable diagnosis with presence of both a rapidly progressive dementia and periodic generalized sharp waves on an EEG plus at least two of the following:
- myoclonus
- cortical blindness
- ataxia, pyramidal signs, extrapyramidal signs
- muscle atrophy
- mutism
Of the three main symptoms of normal pressure hydrocephalus, which is the least likely to improve after a shunt is placed?
the dementia
