Delirium is a condition that occurs commonly in older people. The rising elderly population means more cases of delir ium to manage, emphasising the need for capacitybuilding to manage this condition in hospitals, at home or in 24-hour residential care homes. Terms such as acute confusional state, clouding of consciousness, Bell’s mania or ICU Psychosis may be used to describe this condition.

Delirium is a cluster of a few symptoms that characteristically include sudden onset of change in behaviour or reduced cognitive function, fluctuating nature of its intensity or with a brief period of normalcy called a lucid interval, worsening in the evening called sun-downing and disturbance of sleep-wake cycle. This condition can be due to one or a combination of a few medical causes affecting the body or brain. Therefore, detecting the underlying condition at the earliest is a priority, which if not done, may lead to further worsening or even death. Management is best done by a team of specialists led by the General Medicine discipline with expertise.

Quite often such patients may get referred to a psychiatrist, because the main presenting problem is sudden behaviour change, leading to wandering, restlessness, not able to speak appropriately or even aggressive behaviour. Imagine such aggressive behaviour occurring in the ICU, trying to remove their IV lines or pull wires or push equipment or wanting to go out; it would become inevitable to use restraints in the form of physical means or suitable medication for sedation. Due to such behaviour, family members or even sometimes physicians asking for inpatient psychiatric care due to the patient’s unmanageable situation is not uncommon. The lead physician who is trying to treat the underlying cause is best placed to decide the setting that is appropriate.

Many times, delirium persists despite treating the cause but still requires hospitalisation due to caregiving issues at home; thus, it seems ideal to develop an innovative cost-saving ‘step down 24 hour less intense rehabilitation kind of ward’ in multispeciality general hospital premises with all medical assistance available in the close vicinity. Let us consider a case scenario. An elderly man has become forgetful of recent and past events, and is unable to recognise self or family members, place, and time. His behaviour suggests he is literally confused. All this started suddenly five days back. Also, family members noticed that the behaviour changed in intensity over different times of the day.

They noticed times when the man was able to recollect and seemed to talk normally for a few minutes, but later again there was confusion. The behaviour was getting worse in the evenings and present throughout the night. He would not sleep till the early morning hours; however, behaviour seemed relatively manageable in the mornings. His focus on one task at a time was poor and one or more family members needed to keep a close watch. He was brought to a psychiatrist and was informed that some common blood tests were normal. There was no fever and no physical complaint.

A simple urine test detected suspicion of Urinary tract infection (UTI), which was confirmed by a Urine culture test report after two days. This required antibiotics based on the sensitivity report. In elderly people, a commonly occurring treatable UTI can cause major behaviour changes that require hospitalisation or full-time caregiving till it is treated. In one scientific article, it is said that in 2011 in the USA, there were 400,000 hospital admissions due to UTIs with an estimated cost of $2.8 billion. In the UK, it was reported to have cost 434 million pounds to treat an unplanned 184,000 admissions in the years 2013-14.

Apart from possible drug resistance issues, the main issue was unmanageable delirium. Despite the underlying infection, which was the culprit being treated with the right antibiotic course, the delirium ran a fluctuating course and took 1-2 extra weeks to subside. Delay in the fading of delirium occurs characteristically in elderly people, in contrast to working-age adults. Here the UTI is just one such example. Some other common causes of delirium include low blood sugar levels, low or high levels of sodium or potassium, increase in ammonia levels, kidney failure causing high urea levels, chest infection, infections in the body or brain, cancer in the brain, increased pressure in the brain from different reasons and stroke due to sudden discontinuation of blood supply causing damage to parts of the brain.

Delirium in the elderly also occurs commonly for a brief period after major surgical procedures or while treating severe intensity conditions in ICU settings. It is hypothesised that the chemicals involved in the body repair mechanisms are responsible for the symptoms of delirium. It occurs in the elderly because of a possibly sensitive brain. Those elderly people having repeated episodes of delirium or prolonged periods of delirium need a closer follow-up for managing the underlying physical cause as well as the need to follow them up for possible potential future memory issues.

Several factors such as not sleeping well, pain, constipation, an over-stimulating environment, inadequate intake of food, a combination of side effects of several medications that they may be taking, unfamiliar environment, stressful situation, tiredness, loneliness, and hearing or visual impairment can contribute to the onset or worsening or prolongation of delirium. Delirium is not dementia. But it can co-exist with dementia. Delirium is treatable if the underlying cause is detected and treated early. The abovediscussed information are the basics of delirium.

General Physicians or Critical Care Physicians with more experience in this may provide more information. Delirium occurring due to sudden discontinuation of alcohol or either poisoning or toxicity is not discussed here. There is a need to educate the public as well enhance expertise through PG training and undergraduate medical teaching curriculum. Finally, there is a need for policymaking and guidelines for treating delirium. (The writer is on the NIMHANS Geriatric Psychiatry Faculty and has Geriatric Liaison Psychiatry experience in the United Kingdom.)