Delirium and Dementia

DELIRIUM

When elderly people develop agitation or acute confusion during or after an illness, after undergoing surgery or after being admitted to a hospital, delirium should be suspected. Delirium and dementia are both altered cognitive states of mind but delirium is acute onset while dementia is of chronic onset.

For the diagnosis of delirium, an algorithm called the Confusion Assessment Method (CAM) can be used. This contains four parameters and the diagnosis of delirium requires both items 1 and 2 AND either 3 or 4.
1. Acute onset and fluctuating course of the altered behaviour
2. Inattention - unable to focus attention on what is being said and easily distractable
3. Disorganised or irrelevant or illogical thinking as evident from what the person says. Delusions and hallucinations may be evident from what the patient says.
4. Altered level of consciousness - may be hyperalert (vigilant) or lethargic and drowsy.

When delirium is diagnosed, it is necessary to try and understand what provoked it. Intracranial diseases like strokes, seizures, infections and injuries may be responsible. In older people it is usually extracranial conditions that precipitate delirium. Any kind of infections like chest or urine infections, for example, can provoke delirium. Metabolic factors, hypoxia, drugs and alcohol as well as stress can provoke it too. Being in an unfamiliar environment is also often a trigger for delirium. The pneumonic DELIRIUM can be used as a check list for evaluating delirium where:
D= drugs, E=electrolyte imbalances, L= lack of needed medicines, I= infection, R=reduced sensory input with poor hearing and poor vision being important, I= intracranial disorders, U=urinary retention and fecal retention, and M=myocardial and pulmonary disorders.

Typically people with delirium are considered to be hyperactive and agitated but this is not true. Patients with delirium can also appear hypoactive and lethargic. The way delirium presents depends on the balance between cholinergic (acetylcholine) and dopaminergic(dopamine) neuronal activity in the brain. Agitated delirium can look like a manic psychiatric episode while subdued delirium can look like depression.

In trying to prevent delirium from developing in elderly people,
1. Pay attention to see that they get enough sleep and an adequate diet. Ensure that they do not develop dehydration.
2. Be careful about starting or suddenly stopping drugs that cross the blood brain barrier like sedatives and antidepressants.
3. Keep them in familiar environments as far as possible.
4. When admitted to hospitals, try to orient them to their surroundings, enable them to get up and walk as soon as possible, ensure that they drink enough water and encourage them to use glasses and hearing aids wherever required.
5. Use non-narcotic analgesics like paracetamol instead of morphine if possible.
6. Avoid physical restraints as much as possible

When agitation or restlessness due to delirium becomes unmanageable with soothing words and gentle reassurances, drug therapy may be needed. Drugs that can be useful are haloperidol, risperidone or lorazepam, all in low doses to start with.

References:
1. Delirium in hospitalized patients (NEJM)
2. Elderly care medicine, Lecture notes 8th Edition (John Wiley & Sons, 2012)

DEMENTIA

The term dementia indicates a syndrome, not a specific disease. Unlike delirium, it is not of acute onset. The syndrome of dementia can be broadly divided into two broad categories - cortical dementia and subcortical dementia according to the region of the brain that shows the predominant abnormalities. The commonest form of dementia in the elderly is Alzheimer's disease and it is a form of cortical dementia. The prevalence of dementia increases with age - from about 2% above age 65 years to about 20% above age 80 years according to statistics from UK.

Those with cortical dementia (which includes Alzheimer's disease, vascular dementia, fronto-temporal dementia and dementia with Lewy bodies), have a few common clinical features that have been described as the 4 As - Amnesia (they tend to forget things and their short term memory is bad), Aphasia (they cannot express their ideas well in language), Agnosia (they often mistake objects and persons around them), and Apraxia (they have difficulty in following the steps for doing usual tasks).

The suspicion of dementia often arises because of the history of memory loss and behavioural changes. The diagnosis is often confirmed by using tests of mental ability like the Mini Mental Scale Examination or the Alzheimer's disease Assessment Scale (Cognitive). Whether the dementia is due to Alzheimer's disease or another disease will need to be determined by appropriate tests including imaging studies. The pathological hallmark of Alzheimer's disease in the brain is the presence of abnormal protein deposits called beta-amyloid (seen extracellularly) and neuro-fibrillary tangles containing tau protein (within the neurons). The amyloid hypothesis of Alzheimer's disease states that reduced clearance of normally produced beta-amyloid clogs the cellular machinery of the brain and progressively damages neuronal circuits resulting in dementia.

Memory loss is the defining characteristic of Alzheimer's disease. Some degree of memory loss is also seen with ageing and in the condition called mild cognitive impairment. The important thing to know about these conditions is that the memory loss here is not severe enough to affect activities of daily living.

In managing patients with dementia, it is necessary to provide patients with strategies to cope with their memory loss like diaries and reminder alarms. Their hearing and vision must be corrected if defective. Advice must be given regarding driving and other legal matters like advance directives. Medication for improving cholinergic transmission in the brain (drugs like donepezil, galantamine and rivastigmine) can be considered for mild (MMSE score 21 to 26) and moderate (score 10 to 20) forms of Alzheimer's disease. A drug called memantine that helps to prevent glutamate-induced neurotoxicity is available for treatment of moderate to severe Alzheimer's disease. Caution must be used before prescribing antipsychotics for patients with challenging behaviours and dementia because many of these drugs have adverse cardiovascular side effects and can adversely affect cognition and alertness. It is always good to do a functional assessment (antecedent-behaviour-consequence) before prescribing medication for challenging behaviours in dementia.

In trying to prevent Alzheimer's disease, we need to recognise risk factors that lead to the disease: increasing age, head injury, elevated homocysteine levels, obesity, smoking, hypertension and diabetes. The disease is more common in females, those with reduced physical and mental activity. The likelihood of developing dementia before the age of 60 years increases in those with the gene called APOE epsilon 4. Anxiety, depression and sleep disturbances are often seen in dementia patients and, because these may precede the diagnosis of dementia, there is speculation regarding the cause and effect relationship between them and dementia. Currently some of the accepted ways of trying to prevent dementia include advice to get adequate physical activity, intellectual stimulation, social interactions (avoid loneliness), 7 to 8 hours of sleep everyday, good control of all cardiovascular risk factors like diabetes, hypertension and elevated cholesterol, stop smoking, folic acid to reduce elevated homocysteine levels, enough fruits and vegetables in diet and the ingestion of turmeric for its anti-inflammatory properties.


BEHAVIOURAL CHANGES IN DEMENTIA
Behaviour refers to what people do or say. Behaviour not only defines people in a social context but also affects the way people think of themselves. Whenever behaviour is described in negative terms, there will be negative value judgments created in the mind of the affected person. It is easy to confuse behaviour with character in people with dementia. When behaviour is pleasing, the person may be described as good. When the behaviour causes distress to the caregiver, the person will often be considered to be troublesome or bad. All people who care for patients with dementia must remember that the self-image of their patients can be influenced by the words used to describe their behaviour.  Not only that, these words can also affect the perceptions of others in the team. While it is alright to use words that accurately describe behaviour, it is necessary to avoid words that are judgemental and which cast aspersions on the character of the person. Unlike those with normal memory, the behaviour of people with dementia may not be a conscious and deliberate reaction to inner or outer stimuli.

The term “challenging behaviour” often refers to behaviour that is distressing to the observer. Emerson (2001) defined it as behaviour that is of such duration, intensity or frequency as to threaten either the safety of the individual or those around her. It also refers to such behaviour which prevents the individual from using shared communal facilities. The defining of what is challenging behaviour, and what is not, is sometimes a grey zone . This is because behaviour is often defined in the context in which it is exhibited. Cultural context plays an important role in what constitutes challenging behaviour. Generally, one can say that challenging behaviours are exhibited by people with dementia when they find themselves in an undesired environment, when they cannot get what they want, when there is physical discomfort, or when they feel lonely and want to establish a social connection. In nursing homes, it is not uncommon for challenging behaviours to be triggered because of the clash between the agenda of care in the nursing home (what needs to be done and when it should be done) and the patients’ own agenda (what they want and when they want it).

Restlessness and aggressive behaviour are not uncommon in patients with dementia. While many lay people tend to assume that such problematic behaviour is the result of dementia, it is wrong to ascribe such behaviour to dementia per se without first trying to find out whether it is due to some kind of physical or emotional discomfort or due to an unmet need (Alzheimer’s Society, 2016). Often pain and subtle infections (for example, infection of the urinary tract) can be the cause of such distressing behaviour. Every effort should be made to look for such triggers. Challenging behaviours can also result from the nature of the interactions between the carer and the patient (more likely when the carer is too harsh or domineering) and the nature of the environment (lack of privacy, noise, uncomfortable ambient temperatures, for example, can provoke challenging behaviours).

Wandering about aimlessly, aggressiveness and agitation are often the commonly seen forms of challenging behaviour in nursing home residents with dementia (Aalten et al., 2006). A study involving elderly people with dementia in nursing homes found that pain was a common cause of verbal aggressive behaviour (Ahn & Horgas, 2014). 

Many people with dementia are medicated for non-psychotic symptoms like agitation, aggression, anxiety, pacing and repetitive speech. This may be because the people caring for such patients find it convenient to do so. However, chemical restraint using medication should never be the first line of management for patients with dementia exhibiting challenging behaviour. Antipsychotic drugs can be harmful with important side effects. A study reported in the New England Journal of Medicine (Schneider et al., 2006) noted important adverse effects of olanzapine (a commonly used atypical antipsychotic) like confusion, sedation, falls and Parkinsonism in patients with Alzheimer’s disease who were treated with this drug. There are also reports in the literature about the increased risk of stroke and faster cognitive decline when antipsychotic drugs are used in patients with dementia. Hence the indiscriminate use of such drugs in patients with Alzheimer’s disease must be avoided. Even when drug trials report the benefit of an antipsychotic drug in safely reducing challenging behaviours, it is good to remember that drug trials report efficacy in terms of a reduction in negative behaviours, not in terms of improved well being. A reduction in negative behaviour may simply be because of excessive sedation. It is not a good thing to keep dementia patients always sedated because it takes away their limited ability to express distress and discomfort .

Functional assessment is a good way to plan an appropriate response to challenging behaviour. Unfortunately functional assessment is often overlooked while planning a response to problem behaviour of any kind. A simple method of doing a functional analysis is the A-B-C method which requires recording the behaviour (B) that happened as well as the antecedent (A) or situation that immediately preceded it and what was done, or the consequence (C) that took place because of that behaviour. The ABC method helps carers understand the hidden reasons behind distressing behaviour. By requiring a series of direct observations before making a conclusion, it enables a true understanding of why a particular behaviour happened. The pattern that is derived from multiple direct observations is invaluable in providing clues for planning appropriate management strategies.
Functional analysis shows us how patients’ behaviours in the future may be determined by the way current behaviour is managed. This will lead to an appreciation of how the consequences to current behaviour can become triggers (or antecedents) for future challenging behaviours. 

The management decisions made after functional analysis are more likely to be beneficial than those decisions made without it. The sad truth, however, is that many caregivers often do not take the time to do a functional analysis of challenging behaviour in dementia patients. Even though strategies that are prescribed after functional assessment are more likely to produce the desired response in the patient, health care workers and family members caring for such patients may be more inclined to make snap judgements and decisions when confronted with challenging behaviour. It is good to remind ourselves that functional assessment is an important aspect of patient-centred care and better understanding will always lead to better outcomes. The ABC functional assessment tool should be considered as a part of patient-centred care for dementia patients.

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