Neurology
Internal Medicine
Delirium can occur due to multiple predisposing factors that can be present simultaneously. These factors impair the normal activity of brain signals, resulting in confusion. It can be caused by trauma or injury, systemic diseases, infections, medications, or drug intoxication. Trauma or injury directly affecting the head region can cause delirium and other relative symptoms. Certain conditions such as pneumonia, sepsis, liver failure, kidney failure, hypo or hyperthyroidism, etc., can impair your brain’s normal functioning to a certain extent.
Multiple infections can also be causative factors for delirium. Some of these infections include urinary tract infection, meningitis, encephalitis, acute viral infections, malaria, etc. Certain medications may also cause short-term delirium as a side effect. These medications include antihistamines, benzodiazepines, opioids, corticosteroids, anticonvulsant drugs etc. Another important contributing factor is drug intoxication. Excessive intake of alcohol or drug abuse can disrupt the brain's cognitive functions, leaving you in a confused and dizzy state. On the contrary, abrupt withdrawal from these factors can also cause delirium. Other causes of delirium may include dietary insufficiency, dehydration, sleep deprivation, stress, depression, etc.
Based on neurological activity, delirium is divided into three types.
Hypoactive delirium occurs along with silent confusion, e.g., the person may look at a wall with confusion. It can be mistaken as depression in some cases.
Hyperactive delirium presents with extreme signs of agitation and irritability. The affected person may yell or shout due to a lack of understanding and confusion.
Mixed delirium can appear with both kinds of symptoms. The person may go from a hypoactive state to a hyperactive one and vice versa.
Risk factors for delirium are linked with its underlying causes. Aging is a significant risk factor, especially in the presence of other causative factors such as a systemic illness, medications, psychological illness, etc. History of trauma or injury to the head, stroke, or dementia may increase the risk of delirium. In some cases, delirium may also develop after a major surgery, such as repair of hip fracture. If you are severely dehydrated or lack the necessary nutritional factors, you may experience reduced brain activity. Alcohol and drug intoxication are also significant risk factors. Stress, depression, anxiety, chronic pain, lack of sensory input (vision, audio, etc.), lack of mobility, or presence of other systemic illnesses can also trigger delirium.
Delirium is frequently observed in old-age persons over the age of 65 years. Those in intensive care units or having prolonged hospital stays have developed delirium. It is much more prevalent among males than females.
Signs and symptoms of delirium may vary depending upon its severity. State of confusion and dissociation from the surrounding environment are common signs. You may also experience difficulty performing cognitive functions such as speaking, reading, writing, comprehending a conversation, etc. A person having delirium may slur their words while trying to communicate. They may also have difficulty concentrating on a subject. Visual or auditory hallucinations are also common. Disturbances in sleep patterns, restlessness, emotional instability, memory loss, difficulty in walking or maintaining posture, etc., are other few symptoms of delirium.
Diagnosis of delirium involves multiple steps, including history, mental assessment, clinical examination, and necessary diagnostic tests. A family member or caregiver often explains the history of symptoms. The history onset, duration, severity, and other associated symptoms should be noted to separate it from dementia. Mental evaluation is done by a specialist, which involves using Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria. A simpler version of it is the Confusion Assessment Method (CAM). A person with delirium presents with four signs: confusion, inattention, disorganized thinking, and an altered level of consciousness. Lab tests are done if your doctor suspects an underlying infection or disease as a cause of delirium. These may include CBC, ESR, urinalysis, LFTs, RFTs, thyroid function tests, serum electrolytes, etc. Radiographic imaging may be necessary in case of previous trauma or surgery.
Delirium is often misdiagnosed due to its similarity of symptoms with other mental disorders. They may include dementia, depression, schizophrenia, bipolar disorder, and acute psychosis. It is necessary to differentiate delirium from these disorders using history and other diagnostic tests.
Treatment of delirium begins with eliminating the causative factor, whether due to an infection, trauma, medication, or drug intoxication. Treatment of the underlying cause is the first step towards reversing delirium and reducing its recurrence. Patients with delirium also require constant supportive care, especially during an acute episode, because they cannot understand their surroundings and may hurt themselves or others somehow. If there is a life-threatening case, it needs to be managed immediately by maintaining oxygen saturation levels and other vital signs. Patients are kept in a hospital room or a separate room at home where sensory overload (light, sounds, and temperature) can be managed. If possible, proper diet, water intake, and physical activity should also be maintained.
Antipsychotics, especially haloperidol, is a drug of choice in treating delirium. Other antipsychotics, such as droperidol, chlorpromazine, olanzapine, etc., may be prescribed. Benzodiazepines such as lorazepam may be prescribed in limited cases to lessen the symptoms of delirium. Other medications are given accordingly to treat an underlying infection or disease.
Delirium can be a life-threatening condition if not diagnosed and treated properly. Older people with delirium have been noticed to have a higher mortality rate, especially if they had a secondary disease. Treatment and supportive care can help prolong the life of a person.
Prevention techniques can be employed to reduce the recurrence of delirium episodes. The aim is to lessen the occurrence of risk or triggering factors as much as possible. Lighting, noises, and room temperature for a delirium patient should be regulated to avoid sensory overload. Sufficient dietary and water intake is suggested to reduce weakness. The patient is advised to walk or do minor exercises to maintain mobility and orientation. Supportive care by a family member or caregiver is beneficial in preventing acute delirium.
Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available. Last reviewed by Dr.Saad Zia on May 06, 2023.
Delirium is a short-lasting state of confusion that can render the affected person incapable of understanding their surroundings or performing basic cognitive functions. It occurs due to various factors, but aging is one of the most common factors. The presence of other secondary factors in older people can increase the risk. Delirium may last from a few hours to a few states, depending on its severity. You may experience extreme confusion or dissociation from the environment or people around you. Delirium cannot be managed well at home and requires professional medical care.