Understanding the signs and symptoms of delirium is key to an early diagnosis, which is crucial for treating and resolving the condition.
For centuries, physical illness has been known to be associated with a sudden and dramatic change in the mental state of some individuals. Such patients can often display a range of frightening symptoms, with disturbances in orientation, consciousness, and perceptions.
This condition is best known by the term delirium, derived from the Latin word "delire", which means "deranged". This can be a distressing experience for the patient, relatives, and the staff managing the patient, and can also lead to serious health-related consequences. This is why the swift identification of delirium and management of the condition is imperative.
Prevalence of Delirium
Delirium is a common condition, appearing in 10 percent to 20 percent of medical inpatients. Age appears to play a role in the prevalence of delirium, occurring in 1.1 percent of those over the age of 55, and in 13.6 percent of those over the age of 85 from a community sample in one study. Those who reside in nursing homes and other residential facilities are also particularly at risk, with some estimates stating a prevalence of 10 percent to 45 percent.
Risks of Delirium
Patients who suffer from dementia are also at higher risk of developing delirium once they develop a physical illness. Other risk factors for delirium include severe pre-existing illnesses, recent surgeries, concurrent use of multiple drugs, illicit drug and alcohol dependence, as well as sensory impairments, such as hearing or visual deficits.
Importance of Detecting Delirium
The swift identification and management of delirium is vital as its presence often signifies a poorer prognosis. In those aged 65 years and above, the presence of delirium is associated with higher mortality, with up to 50 percent dying during their admission and a further 25 percent dying in the first six months after diagnosis. Delirium patients in this age group are also three times more likely to require institutional care as the hyperactive form of delirium, in particular, is associated with a higher risk of falls and by extension, bone fractures and head injuries.
Identifying Delirium
Delirium can be identified with careful history taking, particularly from a reliable caregiver, or family member, focusing on the patient’s cognitive and physical functioning prior to the development of the illness. Blood tests, as well as the appropriate X-rays and scans, are crucial in identifying the causes of delirium and need to be done as early as possible. A thorough physical examination, along with cognitive tests administered by healthcare staff, is also vital in establishing the diagnosis.
Symptoms of Delirium
Some of the clinical features of delirium are:
Psychomotor Disturbances
Psychomotor refers to the origination of movement from conscious mental activity. These disturbances can be divided into three categories:
• Hyperactive delirium — accounts for roughly 20 percent of all cases of delirium. Patients may appear to be agitated and aggressive, often in response to abnormal experiences, such as hallucinations and delusions. These are often obvious and may prove a challenge to manage in the ward as patients may pose a risk to themselves or others.
• Hypoactive delirium — accounts for almost 80 percent of cases of delirium. May often go unnoticed as patients may often just appear quieter, less active and less alert, and this may lead to a delay in diagnosis and intervention. They may also start to drink and eat less, which can often be mistaken for depression.
• Mixed delirium — patients may experience a combination of both hypoactive and hyperactive symptoms that fluctuate throughout the day.
Memory Impairment
This is a common feature in delirium, with patients often finding difficulty in registering new information, which is further impaired by the attentional difficulties described above. Impairment of short-term memory can be particularly obvious when a patient is disoriented to time, place, and person. Long-term memory tends to be affected less than short-term memory.
Emotional Changes
Patients with delirium can often display various emotional states that are out of character, such as extreme anger, elation and even terror. These symptoms may be a response to delusions and hallucinations that the patient is experiencing and may lead to behaviours that predispose themselves and others to harm.
Altered Cognition or Perception
Patients with delirium may also experience distressing symptoms, such as misinterpreting their environment (illusions), perceiving non-existent stimuli (hallucinations) or have strongly held unshakeable false beliefs (delusions). The delirious patient may misinterpret the actions of a nurse attending to him as malicious and perceive that she is giving him poison rather than medicine, which could further be supported by the hallucinatory voices or visions that the patient may experience. These symptoms could result in the patient trying to defend himself by acting aggressively.
Impairment of Consciousness
This is when the patient's awareness and responsiveness to his or her surroundings are diminished. This symptom usually fluctuates throughout the day and can range from having mild difficulty in sustaining attention or focusing, to excessive drowsiness to the point of appearing unconscious.
Management of Delirium
The management of delirium involves targeting a few key areas, the most important of which is to treat the underlying physical illness that is causing it. Once a thorough investigation has identified all the potential causes, the swift introduction of appropriate treatments will play a crucial role in resolving delirium as quickly as possible. In some cases, this could take months.
Optimising the Patient's Environment
Optimising the patient’s environment is an important part of the management of delirium, and keeping the environment as consistent as possible is crucial. This can include placing familiar items from home at the patient’s bedside or having the same staff members attend to the patient.
Involving the Family
Involving the family may help in calming the patient down. Providing ample access to calendars, clocks and verbal reminders can play an important part in orientation to reality. Also, patients should always be provided with enough hydration and food, and be kept as pain-free as possible.
Treatment of Delirium
Medications, including antipsychotics such as Haloperidol, can also be helpful in reducing some of the symptoms of delirium, although its use should be kept to a minimum.
Delirium is a common condition, particularly in our society with its rapidly expanding elderly population, and can give rise to serious negative outcomes. An adequate understanding of the causes, risk factors, management, and the signs and symptoms of delirium is therefore crucial in ensuring better outcomes for patients.
By Dr Abishek Mathew Abraham (Associate Consultant, Psychological Medicine). Dr Abraham completed his undergraduate medical studies in 2007, having trained at both the Royal College of Surgeons in Ireland and Penang Medical College, Malaysia. He obtained his Master of Medicine in Psychiatry from the National University of Singapore in 2013 and subsequently obtained his membership at the Royal College of Psychiatrists, United Kingdom, in 2014. He currently works in General Psychiatry at Changi General Hospital, with a special interest in both adolescent psychiatry and autism spectrum disorders. He is also a visiting consultant at KK Women’s and Children’s Hospital.
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