24 February 2010

Geropsychiatry: Delirium and Dementia

Geropsychiatry: Delirium and Dementia
By:Robert Averbuch, MD
Assistant Professor
Department of Psychiatry

Disorders of Cognition
* DSM-IV devotes an entire section to a subset of “organic” disorders that primarily affect cognition: “Delirium, Dementia, and Amnestic and other Cognitive Disorders”

What is “organic”?
* Previous differentiation between mental disorders with a clear “physical or biological” etiology (Organic) and those without (“Functional” or “Primary”)
* Falsely implied that Functional (or primary) disorders have no underlying pathophysiological basis
* Primary mental disorder- not due to a GMC or substance

Disorders of Cognition
* Delirium-disturbance in consciousness and cognition that develops rapidly
* Dementia- multiple cognitive deficits that include memory disturbance
* Amnestic Disorder- primarily memory impairment

Delirium
Delirium: defined
* Disturbance of consciousness (awareness of the environment) and attention,
* PLUS…
o Changes in cognition (ie, “thinking”-memory, orientation, language, etc) OR
o Perceptual disturbances

The Course of Delirium
* Evolves rapidly (hrs to days)
* Usually resolves rapidly as well:
o May be self-limited, persist for weeks, or progress to death
* Degree of impairment fluctuates

Delirium: Associated Features
* Disturbance in sleep-wake cycle
* Easily distracted by irrelevant stimuli
* Changes in activity level
o Restlessness, hyperactivity
o Picking at clothes, getting out of bed
o OR hypoactivity (lethargy)
* Emotional disturbances- mood lability, anger, irritability, euphoria, apathy

Delirium: Associated Features
* Speech or language disturbances
* Perceptual abnormalities- common:
o Illusions, hallucinations, delusions
* Neurological deficits/dysfunction

What Are the Causes?
* DIRECT: Brain pathology: head injury, seizures (during and after), strokes, infections
* INDIRECT: Systemic Illness: electrolyte abnormalities, dehydration, uremia, hepatic encephalopathy, cardiovascular compromise

More Causes of Delirium
* Sensory deprivation
* After surgery (post-operative state)- ie. “ICU Psychosis”
* Side effects of medications or toxins or with abused recreational drugs:
“Substance-Induced Delirium”
o Ex. NMS (Neuroleptic Malignant Syndrome)
o Ex. Serotonin Syndrome

Treating Delirium
* Considered a Medical Emergency
* Supportive care in an ICU setting
* Safety- close monitoring
* Remove offending agent, treat underlying cause

Dementia
Hallmark is Memory Impairment
* Memory problems usually evident early
* Memory impairment alone is not enough to make the diagnosis…

Dementia- defined
* Memory problems AND at least one additional cognitive deficit:
o Aphasia
o Apraxia
o Agnosia
o Problems with “executive functioning”

Details, Details: Aphasia
* Aphasia is a drop off in language function that shows up in a variety of ways

Apraxia
* “impaired ability to pantomime the use of known objects or to execute known motor acts”

Agnosia
* Trouble recognizing or identifying things despite intact sensations (ex. You can see fine, but you can’t recognize a stop sign)
* May include difficulty recognizing family members or even themselves in the mirror

Disturbances in Executive Functioning
* Abstract thinking
* Planning, initiating, sequencing, and stopping behaviors
* May manifest as trouble with novel tasks or new situations

Associated Features
* Spatial disorientation
* Poor insight and judgment means…they get themselves in trouble by overestimating their abilities and underestimating risks
* Perceptual Abnormalities:
o Delusions- especially persecution
o Hallucinations- especially visual

More associated features
* Personality Changes:
o Disinhibition
o Neglect of personal hygiene
o Apathy and withdrawal

Course of Dementia
* Course may be progressive, static, or remitting
* Small percentage of cases are reversible

What causes Dementia?
* Alzheimer’s is by far the most common type
* Cerebrovascular Disease
* Degenerative Diseases: Parkinson’s, Huntington’s, CJD (Mad Cow Disease)

More causes:
* Autoimmune Illness
o Lupus
o Multiple Sclerosis
* B12, Folate Deficiencies
* Head Trauma, Brain Tumors
* Infections- like HIV and Syphilis

Alzheimer’s
Dementia of the Alzheimer’s Type (DAT)
* Diagnosis of exclusion
* Hallmark: gradual onset of recent memory problems
* Onset may be early (65 y/o or younger) or Late (over 65)

DAT
* Slowly progressive (8-10 years from diagnosis to death)
* Many show personality changes
* Often with associated behavioral disturbances (wandering, agitation, etc.)

Vascular Dementia
Aka Multi-Infarct Dementia
Vascular Dementia
* Evidence of cerebrovascular disease on physical exam and head scans
* Usually caused by several strokes over time
* Onset abrupt, followed by stepwise, fluctuating course with “patchy” deficits

Treatment of Dementia
* Search for a reversible cause and treat (ex. B12 deficiency, Normal Pressure Hydrocephalus, Syphilis, etc)
* Rule out Pseudodementia (change in cognition associated with depression)
* Environmental/behavioral interventions- ex. no fail environment
* Medications

Medications
* Cholinesterase Inhibitors:
o Aricept (donepezil)
o Reminyl (galantamine)
o Exelon (rivastigmine)

Medications
* NMDA-receptor antagonists
o Namenda (memantine)
o Neuroprotective by blocking excessive glutamate stimulation of the NMDA (N-methyl-D-aspartate) receptor

Geropsychiatry: Delirium and Dementia.ppt

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