Delirium and Dementia

 Delirium and Dementia

Delirium is a complex neuropsychiatric syndrome of multifactorial aetiology and protean manifestations. Many reviews of delirium suggest that delirium is an unpleasant condition for patients (Inouye, 1994; Meagher and Trzepacz ,1998). There are several reasons why this might be so. Perceptual disturbances and delusions are important symptoms of delirium. Behavioural problems and agitation during delirium suggest patient distress. Its phenomenological presentation is highly variable and differs according to etiological causation, underlying pathophysiology, management, and course. Delirium is a syndrome characterized by the rapid onset of variable and fluctuating changes in mental status (cognition) with altered consciousness and impaired attention that fluctuates over time caused by physiologic consequences of a medical disturbance. Delirium is highly prevalent in general hospitals but remains under recognized and undertreated despite its association with increased morbidity, mortality, and health services utilization (APA, 2000; Michaud et al., 2007). Delirium is associated with adverse outcomes, including increased morbidity, increased mortality, and increased health services utilization (Cole et al., 1998; Marcantonio et al., 2000; McCusker et al., 2002; Morrison et al., 2003). Despite these observations, delirium recognition rates are low (12–43%) (Farrell and Ganzini, 1995; Elie et al., 2000; Hustey and Meldon, 2002), and its management remains inadequate in up to 80% of patients (Hustey and Meldon, 2002). This suggests lack of preventive and screening activities, missed diagnoses, and inappropriate management of diagnosed delirium.

 

 Aetiology of Delirium

 

There are a large number of possible causes of delirium and predisposing factors like:

Predisposing factors

 

• Older age
• Pre-existing cognitive function
• Sensory impairment

 

Dementia may be due to varied causes, some treatable and some untreatable. Some notable ones include:

1.     Untreatable causes include:

a)     Alzheimer‘s disease (a hereditary disease - Alzheimer‘s disease is the most common type of dementia in western studies and

b)     Vascular dementia (blood vessel disease). Treatable or partially treatable causes of dementia .

 

2.     Treatable Causes include:

a)       Infections (e.g. HIV, syphilis, urinary tract Infection, respiratory infections, meningitis, osteomyelitis and endocarditis just to mention a few.

 

b)                      Brain tumours and new cerebral vascular events;

c)                       Chronic alcoholism;

d)                      Drug abuse (e.g. Cocaine, heroin);

e)                       Prescription drug overuse (e.g. Sleeping pills, tranquilizers);

f)                        Toxic exposure (e.g. Lead); and

g)       Poor oxygen supply (e.g. Due to pneumonia, heart disease, myocardial infarction).

h)                      Metabolic disturbance

• ↑↓ sodium/potassium/calcium

• ↑↓ glucose

i)         Terminal illness

i)                        Constipation

 Signs and Symptoms of Delirium

The symptoms of delirium come on quickly, in hours or days, in contrast to those of dementia, which develop much more slowly. Delirium symptoms typically fluctuate through the day, with periods of relative calm and lucidity alternating with periods of florid delirium. The hallmark of delirium is a fluctuating level of consciousness.  A delirious person may have a clouding of awareness and consciousness. This impairment of consciousness typically fluctuates, so the person may be aroused and alert for short periods of time before again relapsing into a clouded state. Fluctuation may follow a pattern of diurnal variation, where consciousness levels change as the day progresses. Typically, a delirious person may be more consciousness impaired in the evening and at night.

Confusion may occur in delirium, where the sufferer loses the capacity for clear and coherent thought. It may be apparent in disorganised or incoherent speech, the inability to concentrate or a lack of goal directed thinking. Disorientation describes the loss of awareness of the surroundings, environment and context in which the person exists. Disorientation may occur in time (not knowing what time of day, day of week, month, season or year it is), place (not know where you are) or person (not knowing who are).

Hallucinations (perceived sensory experience with the lack of an external source) or distortions of reality may occur in delirium. Commonly these are visual distortions, and can take the form of masses of small crawling creatures (particularly common in delirium tremens, caused by severe alcohol withdrawal) or distortions in size or intensity of the surrounding environment. Strange beliefs may also be held during a delirious state, but these are not considered delusions in the clinical sense as they are considered too short lived. Interestingly, in some cases sufferers may be left with false or delusional memories after delirium, basing their memories on the confused thinking or sensory distortion which occurred. Abnormalities of affect include any distortions to perceived or communicated emotional states. Emotional states may also fluctuate, so a person may rapidly change between, for example, terror, sadness and jocularity.

Memory deficits, especially where recent events are concerned (e.g., the reason for hospitalization or for care being given by nursing staff), are also prominent in patients with delirium. Patients may report not being bathed or bedding not being changed when, in fact, these events occurred earlier in the day. Disorientation to date, place, and situation is common. However, the latter can go unrecognized if patients are not directly asked for the information.

Patients with delirium may become agitated as a result of the disorientation and confusion they are experiencing. For example, a patient who is disoriented may think he or she is at home instead of in a hospital, and nursing staff may be mistaken for intruders in the home. Consequently, this patient may not comply with bed or activity restrictions and may try to climb over the bedrails to get out of bed. Likewise, intravenous (IV) and oxygen tubing may not be recognized as such, and the patient may remove them.

Sleep disturbances are common in patients with delirium. They may periodically fall asleep during the day and then be awake for several hours during the night. This pattern, combined with confusion, disorientation, and decreased night-time environmental cues, can create an especially hazardous situation in patients who are at risk for falling and pulling out an IV, Foley catheter, or nasogastric tubing.

Several neurologic signs and symptoms may be present in delirium regardless of cause. They include unsteady gait; tremor; asterixis; myoclonus, paratonia (e.g., gegenhalten) of the limbs and especially of the neck; difficulty reading and writing; and visual construction problems, such as copying designs and finding words.

 Essentials of Diagnosis of Delirium

 

Delirium is essentially a clinical diagnosis. The diagnosis is based on the medical history, observed changes in mental status that are related to some underlying medical disturbance. The most important part of diagnosis is determining the cause of the delirium. Tests may include blood and urine analysis for levels of drugs, fluids, electrolytes, and blood gases, complete blood count (CBC), lumbar puncture ("spinal tap") to test for central nervous system infection; x ray, computed tomography scans (CT), or magnetic resonance imaging (MRI) scans to look for tumours, haemorrhage, or other brain abnormality; thyroid tests; electroencephalography (EEG); electrocardiography (ECG and possibly others as dictated by the likely cause.

 

Delirium includes essential diagnostic symptoms (e.g., inattention, disorganized thinking) as well as core features that are consistent in presentation (e.g., sleep–wake cycle disturbances, motor activity changes), as well as other features that are more variable (e.g., psychosis, affective changes) and reflect the influence of particular aetiologies, co-morbidities, medical treatments, or individual patient vulnerabilities

For a definite diagnosis, symptoms, mild or severe, should be present in each one of the following areas:

 

a)     Impairment of consciousness and attention (on a continuum from clouding to coma; reduced ability to direct, focus, sustain, and shift attention);

b)     Global disturbance of cognition (perceptual distortions, illusions and hallucinations most often visual; impairment of abstract thinking and comprehension, with or without transient delusions, but typically with some degree of incoherence; impairment of immediate recall and of recent memory but with relatively intact remote memory; disorientation for time as well as, in more severe cases, for place and person);

c)      Psychomotor disturbances (hypo- or hyperactivity and unpredictable shifts from one to the other; increased reaction time; increased or decreased flow of speech; enhanced startle reaction);

d)     Disturbance of the sleep-wake cycle (insomnia or, in severe cases, total sleep loss or reversal of the sleep-wake cycle; daytime drowsiness; nocturnal worsening of symptoms; disturbing dreams or nightmares, which may continue as hallucinations after awakening);

e)     Emotional disturbances, e.g. Depression, anxiety or fear, irritability, euphoria, apathy, or wondering perplexity.

 

The onset is usually rapid, the course diurnally fluctuating, and the total duration of the condition less than 6 months. The above clinical picture is so characteristic that a fairly confident diagnosis of delirium can be made even if the underlying cause is not clearly established. In addition to a history of an underlying physical or brain disease, evidence of cerebral dysfunction (e.g. an abnormal electroencephalogram, usually but not invariably showing a slowing of the background activity) may be required if the diagnosis is in doubt.

 

Delirium Counselling

 

Given the additional emotional distress, often in the context of advanced life-threatening disease, clear and consistent communication with family members is of pivotal importance.  An integrated approach to management involves education of family members regarding the nature of the delirium syndrome, especially the possibility of misinterpreting symptoms (e.g., agitation as pain, perceptual disturbance as other psychiatric disorders, or emotional lability as depression) (Morita et al., 2007). Some indication as to the likelihood of delirium reversal or improvement may help family members weigh the benefit versus the burden of further investigation and treatment.

 

Delirium itself is managed by reducing disturbing stimuli, or providing soothing ones; use of simple, clear language in communication; and reassurance, especially from family members. Physical restraints may be needed if the patient is a danger to himself or others, or if he insists on removing necessary medical equipment such as intravenous lines or monitors. Generally, ensure that the patient is managed in a serene environment free from danger and ensure that in the environment, there are clear cues for orientation to date, time, and place.

 

Incorporate proper nutrition, exercise, and mentally stimulating activity.

Provide support for the family (e.g. education, group therapy).

 

Physical and mental stimulatory aids:

 

·       Exercise – walking, stretching, ball throwing. Identify/encourage previous hobbies.

·       Card/board games; puzzles.

·       Encourage storytelling, singing.

·       Encourage time with others who will stimulate (talkative friends).

 

 Medication Therapy for Delirium

 

Treatment of delirium begins with recognizing and treating the underlying cause. During the search for an underlying medical condition, symptomatic treatment for delirium may include the use of antipsychotic drugs to control agitation and hallucinations, and to clear the sensorium. The decision to use drugs that sedate the patient will be made in cooperation with family members after efforts have been made to reverse the delirium. Symptoms may be treated at the same time. Drugs that sedate (calm) the patient or antipsychotic drugs may also be used, especially if the patient is near death. All of these drugs have side effects and the patient will be monitored closely by a mental health worker. Sedatives or antipsychotic drugs may be used to reduce anxiety, hallucinations, and delusions.

 

If agitation occurs, low dose high-potency antipsychotic (haloperidol 2-5mg po or IM every 4 hours as needed) may be used. Low dose antipsychotic may be used if hallucinations are present as well. Antidepressants, preferably those with little anticholinergic effect may be used to prevent atropine psychosis. They are helpful in treating associated depression. Benzodiazepines may be useful for anxiety and insomnia but have potential to cause uninhibited behaviour (disinhibition) or further cognitive impairment. Benzodiazepine agents with short ½ lives like diazepam should be used in the lowest effective dose on the grounds that that they are well tolerated and specifically treat one of the most unpleasant features of delirium, which is anxiety (Meagher, 2001).

 

 Practice points

 

•     Disorientation is one of the least common problems

•     The mini mental state examination (MMSE) is a poor screening tool for delirium

•     Hypoactive state is more common than hyperactive

•     Motoric state is not a guide to the presence of psychosis

•     The underlying cause should be sought and treated appropriately

•     Fear and anxiety are common and are often overlooked yet easily managed

•     Drug treatment for the delirium is not always needed – there is no drug treatment for a wandering patient

 

 

Dementia is defined generally as a mental disorder causing impaired intellectual functioning (e.g. ability to reason), impaired memory and orientation, distractibility, changes in mood and personality, and impaired judgment. It may be difficult at times to differentiate between dementia and delirium, as there are a number of shared characteristics, particularly cognitive deficits (e.g. memory deficit). In general, a pervasive cognitive and intellectual decline with a lack of impaired consciousness is what distinguishes dementia from delirium.

A thorough mental status exam with particular attention to the evaluation of cognitive function will elucidate symptoms of dementia. The Mini-Mental Status Examination (MMSE) is a screening test that may be used to grossly evaluate cognition and track changes in cognition. The MMSE may also help to distinguish dementia from other conditions that may present with impairments in cognition such as severe retarded depression in the elderly. It contains questions that assess orientation to place and time; capacity to register and recall information; capacity to concentrate or at-tend to information; and language and visuomotor capacity. The patient receives a score for each question answered appropriately on a scale of 0-30. A score below 25 suggests the possibility of impairment while a score below 20 is an indication of significant impairment (see Mini-Mental Status Examination).

Aetiology of Dementia

 

Dementia may be due to varied causes, some treatable and some untreatable.

 

1. Untreatable causes include: Alzheimer‘s disease (hereditary disease) and vascular dementia (blood vessel disease). Alzheimer‘s disease is the most common type of dementia in western studies.
2. Treatable or partially treatable causes of dementia include :

 

·         Infections (e.g. HIV, syphilis); CNS infections (syphilis, HIV, Cryptococcal Meningitis, Cytomegalovirus (CMV) Encephalitis and Aseptic Meningitis.

·          Brain tumours;

·         Chronic alcoholism; drug abuse (e.g. cocaine, heroin); prescription drug overuse (e.g. sleeping pills, tranquilizers);

·         Toxic exposure (e.g. lead) and

·         Poor oxygen supply (e.g. due to pneumonia, heart disease).

 

Major characteristics of dementia include:

 

·       Poor memory and forgetfulness (particularly short term recall).      Impaired ability to reason or think logically.                                                                                        

·       Level of consciousness and ability to pay attention is intact (this is impaired in delirium).

People may also experience as a part of dementia:

 

1.           Depression Impaired motivation                                                                                                      2.      Apathy   

3.      Insomnia     

4.      Anxiety  

 5.      Agitation    

6.      Mania  

7.      Irritability or severe mood fluctuation   

 8.      Disinhibition (uninhibited behaviour) 

 9.      Psychosis (delusions, hallucinations)

 Medication Therapy for Dementia

 

If agitation occurs low dose high-potency antipsychotic (haloperidol 2-5mg po or IM every 4 hours as needed) may be used. Low dose antipsychotic may be used if hallucinations are present as well. Antidepressants, preferably those with little anticholinergic effect to prevent atropine psychosis, are helpful in treating associated depression. Benzodiazepines may be useful for anxiety and insomnia but have potential to cause uninhibited behaviour (disinhibition) or further cognitive impairment. Benzodiazepine agents with short ½ lives should be used in the lowest effective dose.