FA Cognitive Disorders Flashcards
What are the clinical manifestations of Alzheimers?
Progrssive decline in cognitive functions, esp memory and language. Personality changes, mood swings, paranoia. Motor and sensory sx absent until late in the course. Gradual course 10 yars from dx to death
What are the Alzheimer genes
Presenelin I, presenelin II, amyloid precursor protein (APP)
What is the major susceptibility gene for Alzheimers?
APOe4. apolipoprotein e4. homozygous (2% of population): 50-90% chance of developing Alzheimers by age 85. Heterogygous (15% of population): 45% chance of developing demntia by age 85. 20% chance in general population
How much are genes involved in Alzheimers.
Rare accounting for only 5% of cases, usually early onset. Most cases, especially after 65 are sporadic.
Neuritc plaques or neurofibrially tangles correlated with severity of dementia in alzheimers
Neuritic plaques.
What is the dominant explanation for Alzheimers?
Amyloid cascade hypothesis. Excess of Abeta peptides due to overproduction or decreased clearance. Alzheimers genes patients are chronic overproducers.
What’s the deal with Ach in Alzheimers?
Decreased Ach due to loss of noradrenergic neurons in the basal ceruleus and decreased choline acetyltransferase (required for ACH synthesis)
What drugs are used to treat Alzheimers?
Mild to moderate: Cholinesterase inhibitors - Tacrine (Cognex), donezipil (Aricept), rivastigmine (exelon), galantamine (razadyne). Slows cognitive decline by 6-12 months. For moderate to severe disease use NMDA antagonists such as memantine (namenda)
What is the pattern of cognition in vascular dementia?
No specific pattern of cogition defines vascular dementia
What symptoms are common in vascular dementia?
Laterizing signs: hemiparesis, ataxia, psudobalbar palsy (extreme emotional lability, abnormal speech cadence, dysphagia). Depression, anger and paranoia are common.
How is vascular dementia treated?
Cholinesterase inhibitors used successfully. Otherwise physical/emotional support, etc. Antihypertension meds may prevent
What are Lewy neurites?
pathological aggregates of alpha synuclein. They are more closely linked with clinical sx than lewy bodies.
What are the core features of Lewy Body dementia
Waxing and waning of cogition, parkinsonism, sensitivity to neuroleptics and visual hallucinations
How do you treat lewy body dementia?
Cholinesterase inhibitors help improve visual hallucinations, atypicals have been slightly effective in stopping delusions and agitation, psychostimulants/levodopa/caribodpa/dopamine agonists may imrpove cogition, apathy, clonazepam for REM sleep behavior disorder
Mutation in what gene is associated with Pick Disease/FTD?
20-30% familiar. May be a/w with progranulin or MAPT gene
What parts of cognition are well preserved in FTD?
Memory, language and spatial functions are well preserved
What is the pathology of FTD/Picks?
Marked atrophy of the frontal and temporal lobes. Neuronal loss, microvacuolization, and astrocytic gliosis in cortical layer 2. only moderate correlation between clinicl and pathologic findings
What is usually preseved in HIV dementia?
Language
What is the pathology of Huntington disease?
Expanded trinucleotide CAG repeats. Longer the CAG repeat, the earlier the age of onset
How do you diagnosie Hungtintons?
MRI - caudate atrophy and sometimes cortical; genetic testing
How does dementia progress in Huntingtons?
1 year before or after the chorea.Patients are often aware of deteriorating mentation.
What is the age of onset for Hungtingtons?
35-50
Dementia due to parkinsons is exacerbated by which medications?
Antipsychotics
What is the pathology of PD?
Loss of neurons in the substantia niagra which supplies dopamine to the basal ganglia => decreased dopamine and loss of dopaminergic tracts. Similar to Alzheimers - senile plaques and neurofibrillary tangles, loss of neurons and decreased choline acetyltransferase
PD sx?
Dementia similar to Alzheimers. Parkinsonism (bradykinesia, cogwheel ridigidity, resting tremor, masklike facial expression, shuffling gait, dysarthria)
Wht are the 3Ws of normal pressure hydrocephalus
Wobbly (apraxia - often appears first), Wet and wacky
dementia in normal pressure hydrocephalus is reversible or irreversible
Usually reversible
Normal pressure hydrocephalus patients have what in brain?
Englarged ventricles with incresed CSF pressure. Etiology is idiopathic or secondary to obstruction of CSF reabsorption due to trauma, infection or hemorrhage.
Causes of Delirium
AEIOU TIPS - Alcohol/drugs toxcity or withdrawal, E - Eletctrolyte abnormality, I - iatrogenic (anticolinergics, benzos, antiepileptics, blood prssure meds, insulin, hypoglycemics, narcotics, steroids, h2 receptor blokers, NSAIDS, antibiotics, antiparkinsonians), O-oxygen hypoxia (bleeding, central venous, pulmonary), U- uremia, hepatic encephalopathy, T - trauma, I - infections, P - poisons, S - seizures
What are the most common causes of delirium
Infections, medications, drug toxicity/withdrawal, and electrolyte imbalances
what meds can be used for symptomatic treatment of the delirious patient?
esp for agitation, neuroleptics: haldol is most studient and can be given po/Im/iv. Benzos EXACERBATE delirium.
What are the most common types of dementia
Alzheimers and then vascular dementia
What is delirium
Waxing and waning consciousness with reduced ability to focus, sustain or shift attention. A CHANGE in cognition or development of perceptual disturbance. Disturbance lasts over a short period of time
What is dementia
Change in cognition without alteration in consciousness
What is the workup for reversible causes of dementia
CBC, electrolytes, TFTs, VDRL/RPR, B12 and folate levels, Brain CT or MRI
What is the diagnosis criteria for dementia?
Memory impairment and at least one of the following APRAXIA, APHASIA, AGNOSIA, DISTURBANCE IN EXECUTIVE FUNCTIONING (planning, organizing, abstracting, sequencing). These disturbances cause significant social or occupational functioning and these deficits do not occur in a period of delirium.
what medical condition can cause reversible dementia?
Hypothyroidism. Usually accompanies by depressed mood and lethargy.
What is the MMSE?
1) Orientation time - date, month, year (5 points), place - city, state, hospital (5 points)
2) Registration - name three objects and repeat them (3 points)
3) Attention and calculation. Serial 7s or spell world backwards (5 points)
4) Recall - name 3 objects 5 minutes later (3 points)
5) Language. name a pen and clock (2), say no ifs and or buts (1), three step command (3)
6) read and obey following. close your eyes, write a sentence, copy design (1, 1, 1). total 30 points. dysfunction is less than 25 points
