Delirium and Dementia Flashcards
Definition of delirium
Disturbance of consciousness (reduced clarity of awareness of environment) with reduced ability to focus, sustain or shift attention
Change in cognition (#1 is disorientation, also memory, language) or the development of a perceptual disturbance not better accounted for by dementia
Disturbance develops over short period of time (usually hrs to days) and tends to fluctuate over course of the day
Causes of delirium
Non-structural
1) Infectious - meningeal infections (bacterial/fungal), encephalitis (viral), cerebral abscess (bacterial/fungal)
2) Toxic** - Sedative hypnotics drugs (benzos, barbs, alcohol), pain meds (opiates), psychotropics (PCP, TCA overdose, other drugs (penicillins, cephalosporins, salicylates, carbon monoxide, anticonvulsants, clonidine, cefepime, anticholinergics), drug withdrawal (alcohol)
3) Metabolic** - Systemic hypoxia, hypoperfusion, hypoglycemia, hyperglycemia, hyponatremia, hypernatremia, hypercalcemia, thiamine def, hyperthyroid, hepatic disease, renal failure, hypercarbia from pulm failure, hyperthermia, sepsis, systemic infection, TTP
If lytes are normal, consider ABG for lung issues.
UTI is common - mechanism may be secondary to inflammatory milieu (cytokines…)
4) Epileptic
Structural
1) Vascular - acute IPH, acute SAH
2) Traumatic - acute epidural hematoma, subdural hematoma, diffuse axonal injury, concussion
3) Neoplastic - mass lesion, leptomeningeal mets
Non-neuro etiology is most common (toxic, metab, infx)
Neuro etiology rarer (epileptic*, parietal lesion, multifocal emboli, CNS infx)
Note: remember we can have non-convulsive status
In ALL patients, think drugs. Young is illicit. Old is Rx.
Workup of delirium
Acute delirium should be approached as a medical urgency as many of the etiologies can lead to rapid demise
Standard workup should have:
1) CBC
2) Na, Ca
3) Serum gluc
4) Renal and hepatic tests
5) UA
6) Blood Cx
7) UTox
The following should be considered depending on the circumstance:
1) ABG
2) CXR
3) HCT
4) LP
5) EEG
Management of delirium
1) treat underlying cause
2) Avoid any benzos for agitation
3) Freq re-orientation
4) Window bed
5) Allow family to stay overnight
6) Low dose atypical neuroleptics if needed
7) Avoid physical restraint in almost all cases
8) Give thiamine
Delirium prognosis
Delirium in hospitalized elderly has poor prognosis
50% will require discharge to institutions
Many will die within a year
Delirium therefore is a symptom of a serious underlying process
Dementia is a risk factor for delirium
Dementia definition
Development of multiple cognitive deficits manifested by both
1) memory impairment (can’t learn new information or recall previously learned info)
2) One or more of the following disturbances: Aphasia, apraxia, agnosia (failure to recognize despite intact sensory function), disturbance in executive function (planning, organizing, sequencing, abstracting)
Cognitive deficits each cause significant impairment in social or occupational functioning. Significant decline from previous level of functioning
For AD - gradual onset and continuing decline
What is the number 1 cause of dementia?
AD
5 cognitive domains
DSM V requires 2 or more to be dementia. DSM 4 required 1 plus memory
1) Memory - temporal
2) Language - frontal (broca’s), temporal (Wernicke)
3) Praxis - parietal - trouble getting dressed, using a device
4) Nosis - Parietal/occipital - ability to recognize surroundings and make sense of them - getting lost
5) Executive function - frontal - managing own finances, making a recipe, usually a later feature
Prosopagnosia
inability to recognize faces
Subacute vs chronic dementia
Subacute - typically caused by metabolic, structural, or infectious process. CJD, B12, Chronic SDH, Mass lesion, endocrinopathy
Chronic - typically neurodegenerative or vascular. AD, Huntington Disease
Cortical vs subcortical dementia
Cortical - involve cortical functions. AD, vascular dementia, FTD
Subcortical - involve subcortical white matter and are typified by overall slowness of thought and decreased motivation. HIV dementia, Parkinson dementia, Huntington dementia
Causes of dementia
1) Neurodegenerative - AD, DLB, Pick Disease, FTD, HD, PD
2) Vascular - multiinfarct, hypoperfusion, CADASIL, Binswanger’s disease
3) Infectious - HIV (R), general paresis, PML (R), SSPE, CJD
4) Structural - hydrocephalus (R), subdural hematoma (R), mass lesion (R), radiation encephalopathy
5) Toxic/metabolic - hypothyroid (R), B12 (R), Korsakoff, Wilson (R), Chronic drug intox (R)
6) Paraneoplastic (R)
7) MS
8) pseudodementia (R)
(R) is reversible
Recs for dementia workup
Depression screen
MRI
TSH/B12
NPH
Triad of Gait disorder, incontinence, dementia (usually in that order)
Caused by pressure on the frontal subcortical fibers by large ventricles
Can be primary or secondary
Diagnosis should be confirmed by objective improvement in gait after removal of CSF by LP or lumbar drain
Alzheimer Disease
Most common form of dementia
Very much disease of memory system first
Risk factors = age, though not confined to the elderly, low education level, Genetic mutation in B-APP, PS-1, PS-2, Down Syndrome
Felt to be caused by accumulation of abnormal B-amyloid plaque
Clinical features:
1) Gradual loss of short term memory
2) Intellectual decline
3) Loss of visuospatial orientation
4) Gradual loss of eloquent speech with relative preservation of superficial speech until late
5) Paranoid delusions and agitation
6) Late loss of motor functions and continence
7) Seizures in 10% of patients
Dx and Tx of AD
Clinical dx. Exclusion of other causes if suspected - routine B12, TFTs, neuroimaging. If indicated RPR, LP, PET, more
Tx:
1) AChE inhibitors provide brief stabilization of decline and delay nursing home placement by less than 1 year - donepezil, rivastigmine, galantamine, tacrine
2) Memantine (NMDA antag) recently approved for moderate to severe. May reduce rate of decline.
3) Supportive management - antipsychotics, antidepressants, anxiolytics
4) caregiver support vital
FTD
Typically involves personality and motivation first
Memory involved later in disease
Large number of diseases within this category
Commonly misdiagnosed
Dementias associated with movement disorders
1) HD - triad of dementia, chorea, and FHx. autosomal dominant, caused by CAG repeat in Huntingtin protein on chromosome 4
2) DLB - dementia with parkinsonian features
3) Wilson - never forget to consider it in younger person with dementia, behavioral changes, movement disorder or liver failure. Caused by Cu accumulation in brain due to mutation in ABC transporter gene on chromosome 13. Auto recessive
4) PD - dementia is LATER feature and is subcortical. Seen in 10-20% of PD patients.
Lewy Body Disease
Thought to be underdiagnosed
Should not be confused with PD. The dementia should occur within 2 years of the onset of parkinsonism.
More fluctuation than in AD
More psychosis than AD
Exquisite sensitivity to neuroleptics
Extrapyramidal features (rigidity, no tremor)
Sleep disturbances
Hallucinations common - visual
May have a response to AChE inhibitors
Vascular dementia
Can either be caused by multiple small strokes or a few strokes in eloquent locations
Typically more abrupt in onset than AD with stepwise deterioration and focal neuro signs
Treatment is by control of risk factors to prevent further progression
CJD
Prion disease
Multiple causes - sporadic form is 1 in 1 million. Inherited form caused by PrP mutation. Iatrogenic form from dural and corneal grafts. Also a transmissable form.
Rapidly progressive dementia syndrome with myoclonus
Typical EEG pattern (periodic sharp wave complexes)
No treatment is effective for the dementia
Typically causes death within 6 months to 1 year.
Pseudodementia
Caused by depressive syndrome
Withdrawal form social behaviors, disruption in sleep-wake cycle, altered eating pattern
Pay attention to the types of answers given on MSE!
In pseudodementia, patients will often just say “I don’t know” instead of providing near-misses like in dementia.
Anterior vs posterior cortical dementias
Anterior - Tends to produce problems with behavior and executive dysfunction. Patients can lose social graces early while having memory and intellectual functions relatively preserved. Ex is FTD
Posterior - Tend to lose intellectual function while preserving social graces. Ex is AD
CSF in AD
AB1-42 is decreased
Tau is increased
This is specific but not very sensitive
