Cognitive Impairment

Published on the 23 January 2018



Cognitive Impairment



Date Published: 23 January 2018

Author: Sally Moyle

Cover image for article: Cognitive Impairment

Cognitive impairment can affect anyone, and occurs not only as a preexisting condition in someone coming into hospital, but can also develop during their hospital stay

Someone who is cognitively impaired is at a higher risk of developing many preventable complications including falls, pressure injuries, pneumonia, urinary tract infections, functional decline and increased mortality. And, because of these potential complications, they are more likely to have a prolonged hospital admission, be readmitted or enter residential care (Australian Commission on Safety and Quality in Health Care 2018).

Despite the potential devastation it can cause, in Australian hospitals, cognitive impairment remains under-recognised and often misdiagnosed.

In patients over the age of 70, 20% of them will have dementia and 10% will have delirium and let’s not forget that just because someone has dementia, it does not mean that they cannot also develop delirium whilst being in hospital as well. And in general medical geriatric settings, the number of older people experiencing delirium is even higher and sits between 29-64% of older people (ACSQHC 2018).

Many people access health services across the world, and when they do, there is a need for health professionals to not only treat their prioritising health concern, but also recognise and treat any other co-morbidities they may have concurrently, or consequently develop during their hospital stay. This article will help to recognise cognitive impairment and how it can be assessed and treated in a healthcare context.

What is Cognitive Impairment?

Because of the often misdiagnosed or unidentified cognitive impairment in patients, it is important to understand some of the common forms of cognitive impairment, who is at risk and how cognitive impairment can affect the individual.

Generally, people with cognitive impairment will have difficulty with communication, speech, language, memory, attention, thinking and/or judgment. The person may not be able to recognise people or objects and they may also have difficulties carrying out tasks.

Cognitive Impairment - Dementia, Delirium or Depression? | Ausmed

Types of Cognitive Impairment

The two most common forms of cognitive impairment are dementia and delirium, with other forms of cognitive impairment including those with a brain injury, stroke, intellectual disability or drug use (ACSQHC 2018).

It is important to remember that dementia and delirium are not a normal part of ageing, however with an ageing population, we can expect to see the number of people with these forms of cognitive impairment increasing.

There are many similarities between dementia and delirium and they can often be mistaken for one another. Depression is also another condition that can be potentially confused with both dementia and delirium so it is important to ensure a comprehensive assessment is completed of the individual to ensure an accurate diagnosis (ACSQHC 2018).

Dementia, Delirium or Depression?

Dementia Delirium Depression
Duration Chronic condition that is progressive Lasts hours to weeks in duration Can last weeks to months to years
Onset Chronic onset Acute onset Often abrupt onset
Attention Generally normal attention Impaired or fluctuating attention Distractible but minimal impairment of attention
Memory Recent and remote memory impairment Recent and immediate memory impairment Islands of intact memory
Alertness Generally normal alertness Fluctuates between lethargic and hyper-vigilant Alert
Thought pattern May have word finding difficulties and poor judgment Disorganised thinking with slow or accelerated thoughts Thinking intact but with themes of helplessness or self-depreciation

(Agency for Clinical Innovation 2018)

So dementia is a progressive cognitive impairment that affects memory, judgment, language and the ability to perform everyday tasks with Alzheimer’s disease the most common form of dementia. Whereas delirium is a treatable condition and is an acute disturbance of consciousness, attention and cognition that tends to fluctuate during the course of a day (ACSQHC 2018).

It is important to note that delirium has many risk factors associated with it and will result from a complex interplay between these risk factors in vulnerable patients and their health-related events occurring. This can be demonstrated in a patient who may have pre-existing dementia, who is taking multiple medications and also has sensory impairments, who then develops acute delirium after they are given a sedative to help them sleep (ACSQHC 2013).

Some of the risk factors for the development of delirium include:

  • Dementia
  • Older age
  • Other co-morbidities
  • Severity of medical illness
  • Infection
  • ‘High risk’ medication use
  • Diminished activities of daily living
  • Immobility
  • Sensory impairment
  • Urinary catheterisation
  • Urea and electrolyte imbalance
  • Malnutrition

(Ahmed et al. 2014)

Cognitive Impairment Assessment and Screening

Because of the under-identification of people with cognitive impairment in hospital and the potential complications it can cause, it is important that patients undergo cognitive impairment screening and assessments.

The benefits of early screening include not only alleviating any concerns about cognitive impairment but if the screening is positive, it can allow steps to be taken to identify the cause of the cognitive impairment and to determine if it is a reversible condition such as delirium or the result of a medication side effect.  Then treatment can be commenced and potential complications arising from the cognitive impairment avoided (National Institute on Aging 2014).

Often screening for cognitive impairment takes less than 10 minutes to perform, and if the results are positive, then a more detailed cognitive impairment assessment will need to be attended. Also during cognitive impairment assessments, family members and close companions can be good sources of information about the individual (National Institute on Aging 2014).

Cognitive Impairment Treatment and Nursing Interventions

It is important to remember that whilst the individual with a new or old cognitive impairment is in hospital they are not only dealing with their health condition, but also with the busy and noisy hospital environment which is completely different to what they are used to at home. They are surrounded by numerous unfamiliar faces and different routines which can cause considerable amounts of distress and also exacerbate disorientation which can then further decrease their independence and functional ability (ACSQHC 2013).

Treatment and the implementation of interventions to manage and improve cognitive impairment needs to be inclusive of the family and the patient. It will often involve the development of a management plan which will include reviewing the individuals current medications, as well as evaluating and implementing strategies for behavioural problems (National Institute on Aging 2014).

Management of the cognitively impaired individual whilst in hospital includes identifying and managing any clinical risks such as falls, providing targeted and individualised care to the patient, engaging with carers, ensuring behaviour is managed appropriately and implementing further prevention strategies (ACSQHC 2013).

Management of the cognitively impaired individual needs to be individualised however most hospitals will also have policies and protocols to guide their care.

These nursing management strategies can include ensuring a safe environment for the individual, communication strategies, orientation of the patient, preventing sleep deprivation, avoiding constipation, using sensory aids, managing pain, minimising the use of indwelling catheters, avoiding the use of physical restrains and minimising the use of psychotropic drugs to name a few (ACSQHC 2013).

The goal of management is to address the underlying cause of the cognitive impairment, reduce agitation and distress, support independence and social interaction as well as promote the safety of the patient and enable activities of daily living by involving the patient and their significant others in their care (ACSQHC 2013).



Portrait of Sally Moyle

Sally Moyle is a rehabilitation nurse educator who has completed her masters of nursing (clinical nursing and teaching). She is passionate about education in nursing so that we can become the best nurses possible. Sally has experience in many nursing sectors including rehabilitation, medical, orthopaedic, neurosurgical, day surgery, emergency, aged care, and general surgery.

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2 Total Rating(s)

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Tyson Joseph Peters
15 Jul 2019

informitive and good foundation for further investigation into pt with this dx