Neurocognitive disorders
Neurocognitive disorders (NCDs) affect the structural or functional areas of the brain and cause disturbances in
normal cognition (thinking). The criteria for the various NCDs are based on defined cognitive domains. These
include:
• Complex attention
• Executive functioning: planning, decision making, working memory, responding, and mental
flexibility
• Learning and memory
• Language usage
• Perceptual-motor abilities
• Social cognition: recognition of emotions
Delirium
Delirium is an acute cognitive disturbance and often reversible condition that is common in hospitalized
patients, especially older patients.
Delirium is always secondary to another condition. Medical conditions, substance use (intoxication and
withdrawal), and medication or toxin exposure are possible causes of delirium. If the underlying physiological
disturbances that caused the delirium are corrected in a timely manner, complete recovery occurs. If the
underlying etiologies of delirium are not addressed, dementia and even death may follow.
Clinical Picture
Disturbances in consciousness occur.
Change in cognition occurs.
Develops over a short period.
Is common in hospitalized patients, especially older adults.
Is always secondary to another physiologic condition.
Is a transient disorder.
If the underlying condition is corrected, then complete recovery should occur.
Common Causes of Delirium (Risk Factor)
Postoperative States
• Surgery and other invasive procedures
• Anesthesia medications and pain medications used
Drug Intoxications and Withdrawals
• Alcohol, anxiolytics, opioids, and central nervous system (CNS) stimulants (cocaine, crack cocaine,
and others)
, • Alcohol withdrawal (delirium tremens) is a medical emergency (see Chapter 19).
Infections
• Systemic: pneumonia, typhoid fever, malaria, urinary tract infection, and septicemia
• Intracranial: meningitis and encephalitis
Metabolic Disorders
• Dehydration
• Hypoxia (pulmonary disease, heart disease, and anemia)
• Hypoglycemia
• Sodium, potassium, calcium, magnesium, and acid–base imbalances
• Hepatic encephalopathy or uremic encephalopathy
• Thiamine (vitamin B1) deficiency (Wernicke’s encephalopathy)
• Endocrine disorders (thyroid and parathyroid)
• Hypothermia or hyperthermia
• Elevated temperature is most common cause in children
• Diabetic acidosis
• Vitamin B12 and folate deficiencies
Drugs
• Digitalis, steroids, lithium, levodopa, anticholinergics, benzodiazepines, CNS depressants, tricyclic
antidepressants
• Anticholinergic delirium from the use of multiple drugs with anticholinergic side effects
• Please refer to the American Geriatrics Society 2015 updated Beers Criteria for potentially
inappropriate medication use in older adults.
Neurological Diseases (CNS Pathology)
• Seizures
• Head trauma
• Hypertensive encephalopathy
• Dementia (secondary delirium especially during a hospitalization)
Tumor
• Primary cerebral
Other
• Relocation or other sudden changes
• Sensory deprivation or overload
• Sleep deprivation
• Immobilization
• Pain
• Of people with a terminal illness, 75% to 85% develop delirium near death.
, The detailed features of delirium are as follows:
• Disturbance in attention and awareness, with reduced ability to direct, focus, sustain, and shift focus. There
can be a reduced orientation to the environment. Sometimes the person becomes withdrawn, with little or no
response to the environment.
• Disturbance in cognition or thinking skills: This includes memory deficit, particularly for recent events. The
person can become disoriented to person or place and time. Language deficits, such as rambling speech,
difficulty speaking or understanding speech, and difficulty writing or reading, also occur. There can be
perceptual distortion, including hallucinations (seeing things that don’t exist) and illusions (misinterpreting
things that are seen) and reduced visuospatial ability.
• Specific criteria for the diagnosis are that the symptoms develop rapidly over hours to days and fluctuate in
severity during the course of the day. Sundown syndrome, in which symptoms and problem behaviors become
more pronounced in the evening and at night, is an example of fluctuating symptoms that may occur in both
delirium and dementia.
• There must be evidence that the disturbance develops as a direct physiological consequence of another
medical condition
Behavioral symptoms can include restlessness; agitation and combativeness; disturbed sleep, including
reversal of night–day/sleep–wake cycles; withdrawal; and slowed speech. Emotional responses can be rapidly
changing, with an unpredictable mood/affect. These emotional responses include being irritable and angry,
euphoric, depressed, anxious, apathetic, and paranoid.
There are three different types of delirium:
• Hyperactive: restlessness, pacing, and agitation, with rapid mood swings and sometimes hallucinations
• Hypoactive: reduced motor activity, sluggishness, drowsiness or seeming dazed; least recognized presentation
• Mixed: includes both hypoactive and hyperactive symptoms, switching from one type to another (Mayo
Clinic, 2018)
Neurocognitive disorders (NCDs) affect the structural or functional areas of the brain and cause disturbances in
normal cognition (thinking). The criteria for the various NCDs are based on defined cognitive domains. These
include:
• Complex attention
• Executive functioning: planning, decision making, working memory, responding, and mental
flexibility
• Learning and memory
• Language usage
• Perceptual-motor abilities
• Social cognition: recognition of emotions
Delirium
Delirium is an acute cognitive disturbance and often reversible condition that is common in hospitalized
patients, especially older patients.
Delirium is always secondary to another condition. Medical conditions, substance use (intoxication and
withdrawal), and medication or toxin exposure are possible causes of delirium. If the underlying physiological
disturbances that caused the delirium are corrected in a timely manner, complete recovery occurs. If the
underlying etiologies of delirium are not addressed, dementia and even death may follow.
Clinical Picture
Disturbances in consciousness occur.
Change in cognition occurs.
Develops over a short period.
Is common in hospitalized patients, especially older adults.
Is always secondary to another physiologic condition.
Is a transient disorder.
If the underlying condition is corrected, then complete recovery should occur.
Common Causes of Delirium (Risk Factor)
Postoperative States
• Surgery and other invasive procedures
• Anesthesia medications and pain medications used
Drug Intoxications and Withdrawals
• Alcohol, anxiolytics, opioids, and central nervous system (CNS) stimulants (cocaine, crack cocaine,
and others)
, • Alcohol withdrawal (delirium tremens) is a medical emergency (see Chapter 19).
Infections
• Systemic: pneumonia, typhoid fever, malaria, urinary tract infection, and septicemia
• Intracranial: meningitis and encephalitis
Metabolic Disorders
• Dehydration
• Hypoxia (pulmonary disease, heart disease, and anemia)
• Hypoglycemia
• Sodium, potassium, calcium, magnesium, and acid–base imbalances
• Hepatic encephalopathy or uremic encephalopathy
• Thiamine (vitamin B1) deficiency (Wernicke’s encephalopathy)
• Endocrine disorders (thyroid and parathyroid)
• Hypothermia or hyperthermia
• Elevated temperature is most common cause in children
• Diabetic acidosis
• Vitamin B12 and folate deficiencies
Drugs
• Digitalis, steroids, lithium, levodopa, anticholinergics, benzodiazepines, CNS depressants, tricyclic
antidepressants
• Anticholinergic delirium from the use of multiple drugs with anticholinergic side effects
• Please refer to the American Geriatrics Society 2015 updated Beers Criteria for potentially
inappropriate medication use in older adults.
Neurological Diseases (CNS Pathology)
• Seizures
• Head trauma
• Hypertensive encephalopathy
• Dementia (secondary delirium especially during a hospitalization)
Tumor
• Primary cerebral
Other
• Relocation or other sudden changes
• Sensory deprivation or overload
• Sleep deprivation
• Immobilization
• Pain
• Of people with a terminal illness, 75% to 85% develop delirium near death.
, The detailed features of delirium are as follows:
• Disturbance in attention and awareness, with reduced ability to direct, focus, sustain, and shift focus. There
can be a reduced orientation to the environment. Sometimes the person becomes withdrawn, with little or no
response to the environment.
• Disturbance in cognition or thinking skills: This includes memory deficit, particularly for recent events. The
person can become disoriented to person or place and time. Language deficits, such as rambling speech,
difficulty speaking or understanding speech, and difficulty writing or reading, also occur. There can be
perceptual distortion, including hallucinations (seeing things that don’t exist) and illusions (misinterpreting
things that are seen) and reduced visuospatial ability.
• Specific criteria for the diagnosis are that the symptoms develop rapidly over hours to days and fluctuate in
severity during the course of the day. Sundown syndrome, in which symptoms and problem behaviors become
more pronounced in the evening and at night, is an example of fluctuating symptoms that may occur in both
delirium and dementia.
• There must be evidence that the disturbance develops as a direct physiological consequence of another
medical condition
Behavioral symptoms can include restlessness; agitation and combativeness; disturbed sleep, including
reversal of night–day/sleep–wake cycles; withdrawal; and slowed speech. Emotional responses can be rapidly
changing, with an unpredictable mood/affect. These emotional responses include being irritable and angry,
euphoric, depressed, anxious, apathetic, and paranoid.
There are three different types of delirium:
• Hyperactive: restlessness, pacing, and agitation, with rapid mood swings and sometimes hallucinations
• Hypoactive: reduced motor activity, sluggishness, drowsiness or seeming dazed; least recognized presentation
• Mixed: includes both hypoactive and hyperactive symptoms, switching from one type to another (Mayo
Clinic, 2018)
