Delirium in elderly: identify cause early

Delirium occurs commonly in elderly due to an underlying physical illness, many a time leading to hospitalisation. Ageing, frailty, deafness, visual impairment, surgical procedures are common risk factors. This condition is detected by careful assessment, observation, clinical examination, lab tests and sometimes a brain scan.

Delirium is a short-term confusional state that usually resolves in contrast to dementia, which is more of a chronic, irreversible condition. One should suspect delirium as a co-existing condition, when there is rapid worsening of memory and related functions in any person already known to have dementia.

Family members notice that elderly person has become suddenly confused with no awareness of time, place or is unable to identify familiar persons. The person gets distracted easily. There could be characteristic intermittent clouding of consciousness because of alternating lower level of consciousness and full consciousness.

Typically, the lowering of consciousness begins in the evening and continues through the night. Since their behaviour becomes more agitated, disoriented or unresponsive and unmanageable with the setting sun, it is called “sun downing” effect. A typical complaint is that the person is not sleeping at night and is wandering restlessly. The elderly also experience perceptual abnormalities, like visual or auditory hallucinations, where they seem to be responding in the absence of any sensory stimuli or have distortion in perception such as magnified sensations, that is, louder or brighter than they are.

Common causes could be growth of abnormal bacteria causing infection in the urinary tract or inside the chest. Abnormally high or low levels of sodium from various medical conditions, medications prescribed for high blood pressure, antidepressants or due to excessive drinking of water may be another cause.

As a complication of diabetes, sudden lowering of blood sugar levels can also cause this condition. Abnormally high levels of sugar in the blood, sometimes as a result of infection or due to other causes, can lead to a condition called diabetic ketoacidosis, which needs specialist in-patient treatment with initial ICU care.

Vascular events in the heart or brain occur due to clots or blockages in the blood vessels, leading to stroke or heart attacks. Here, confusion can be one of the signs that poses imminent threat to life needing urgent intervention, with preferred travel in an ambulance with oxygen availability.

A sudden discontinuation in the chronic consumption of alcohol leads to a condition called withdrawal related ‘delirium tremens’ with risk of fits. Many elderly experience confusion after surgeries due to effect of anaesthesia. Consult a specialist psychiatrist or neurologist regarding frequent episodes of delirium to rule out a possibility of early signs of dementia.

When the body starts to repair itself from a sick state, immune mediating chemicals are released, and this is thought to cause delirium. One of the theories is that the brain in elderly is relatively more sensitive to these immunity-related chemicals compared to adults, which is why also it is slow to resolve.

The aim is to detect and treat the underlying cause of this condition early. But despite early treatment, it may sometimes take upto 2-4 weeks to resolve. During the initial period of hospitalisation, patients should ideally be nursed in the side room, where it is quieter with optimum lighting and less stimulation, that is, fewer number of visitors.

Ensuring adequate food and fluid intake, restoring sleep-wake cycle and ensuring regular bowel and bladder habits promote recovery.

Repeated reorientation of the person is needed to reduce fear and anxiety. Certain medications alone or in combination, may worsen confusion. Sedative medication may be helpful, but they can worsen the condition or increase risk of falls, and hence require regular specialist review.

Occasionally, psychiatrists working in liaison with physicians may prescribe a tiny dose of neuroleptic medication to reduce fear, perceptual abnormalities or paranoia. Once the cause has been treated, the person can be managed with support from trained nurses at home with follow up by a medical team.

Family physicians, who know the person well, can identify the signs early and arrange for treatment. Though this condition is frequently seen in general wards and ICUs, no clear standardised protocol seems to be followed.

There is a need for dedicated wards exclusively to manage delirium with trained staff members and regular training workshops for physicians in managing delirium. Further, awareness programmes for caregiving family members may help in reducing the impact and complications, thus increasing the elderly’s longevity of life.

(The writer is consultant psychiatrist and ad-hoc faculty in Geriatric Psychiatry in NIMHANS, Bengaluru)