4AT case examples
These examples are drawn from clinical practice and show how the 4AT is scored in different scenarios. As with all delirium assessment tools, the score provides a guide but not a final diagnosis. In all cases clinical judgement is needed to provide a diagnosis.
You are welcome to use these cases as part of general delirium training and helping practitioners become familiar with the 4AT.
Case 1
Mrs SA is an 84 year old woman with a history of dementia who lives alone and who has carers attending twice a day. She is usually mobile, and can go shopping and visit friends if accompanied. Mrs SA was admitted because she was not answering her phone and her daughter had gone to see her and found that Mrs SA was very sleepy and felt hot. In the emergency department she is diagnosed with pneumonia.
A 4AT is performed. On approach she had her eyes closed and she did not open them initially on request. When asked to say her name she opened her eyes and attempted to say something but this was incomprehensible. She did not respond to other requests to perform cognitive testing, including the AMT4 and Months Backwards.
Mrs SA’s daughter said that though Mrs SA does have problems with her memory she usually manages to look after herself with assistance at home, and she is usually able to converse normally.
4AT scoring:
ITEM 1 – Level of alertness: score 4 (clearly abnormal level of alertness)
ITEM 2 – AMT4: score 2 (untestable)
ITEM 3 – Months Backwards: score 2 (untestable)
ITEM 4 – Acute change or fluctuation: score 4 (clear evidence of change from informant)
4AT total score: 12/12
This indicates multiple features of delirium including altered level of alertness, severe cognitive impairment, and acute change. Note that though cognitive testing or interview is not possible, the 4AT is still scored positive: no patients are Unable to Assess (UTA) with the 4AT.
Case 2
Mr AY is a 70 year old inpatient in a medical ward. He has a history of chronic obstructive pulmonary disease and hypertension. He had been admitted 3 days ago with a chest infection, and he had been treated with antibiotics and steroids. On admission his 4AT score had been 0/12.
On the morning ward round the nurse stated that Mr AY had been restless and confused overnight.
A 4AT is repeated.
ITEM 1 – Level of alertness: score 0 (normal)
ITEM 2 – AMT4: score 1 (unable to say the name of the place (hospital))
ITEM 3 – Months Backwards: score 1 (started but incomplete)
ITEM 4 – Acute change or fluctuation: score 4 (clear evidence of change from informant)
4AT total score: 6/12
This score is above the 4 or above threshold and indicates possible delirium. This mainly comes from the history of change from the informant (nurse on the ward round) and is supported by the change in cognitive function.
Case 3
Mr JB is an 88 year old man who lives alone. He has a history of atrial fibrillation, stroke, depression, prostate cancer, and gout. He is admitted to hospital after having fallen. He is accompanied by his son who states that Mr JB has been having some problems with his memory over the last few months, but that he has not seen a health professional about this and there is no diagnosis of dementia. The son said that Mr JB is his normal self at the time of the consultation.
A 4AT is performed in the medical admissions ward.
ITEM 1 – Level of alertness: score 0 (normal)
ITEM 2 – AMT4: score 2 (did not know age, year, name of the place)
ITEM 3 – Months Backwards: score 1 (incomplete)
ITEM 4 – Acute change or fluctuation: score 0 (no evidence of change from informant)
4AT total score: 3/12
This score indicates cognitive impairment. There is no clear evidence of delirium. Given this score and the history from the son further evaluation for dementia at an appropriate time may be beneficial.
Case 4
Mrs SA is a 96 year old woman who lives in an care home. She has a history of severe dementia. She is admitted having fallen in the care home. In the emergency department an X-ray shows an undisplaced pubic ramus fracture.
Mrs SA had her eyes open on approach. The doctor asked Mrs SA to say her name. Mrs SA said her first name but is only intermittently responsive to other questions including 1-stage commands. She sometimes was able to say yes or no to simple requests but did not always answer, and her answers were inconsistent.
Discussion with care home staff revealed that Mrs SA was usually unable to communicate meaningfully beyond saying yes or no. She was able to walk with a wheeled frame, and usually could eat and drink with assistance.
A 4AT is performed.
ITEM 1 – Level of alertness: score 0 (normal)
ITEM 2 – AMT4: score 2 (untestable)
ITEM 3 – Months Backwards: score 2 (untestable)
ITEM 4 – Acute change or fluctuation: score 0 (clear evidence of change from informant)
4AT total score: 4/12
The score of 4/12 indicates possible delirium. This score results from the untestable scores on items 2 and 3.
At the time of assessment there was no clear evidence of acute change. The 4AT is designed to allow a score of 4 when the patient is untestable, because in acute settings this commonly indicates delirium. However, it is possible for patients with severe dementia and no delirium to receive a score of 4.
People with severe dementia commonly have cognitive deficits that are in practice indistinguishable to those observed in delirium, including inattention. This means that it often difficult to determine if the patient has severe dementia alone, or delirium superimposed on dementia. The diagnosis is also challenging if the patient cannot readily communicate verbally and they express pain or distress through crying out or appearing restless. In such cases it is often unclear if the patient has delirium.
In the present case the most clinically likely diagnosis is severe dementia rather than delirium. Ongoing close monitoring for change or fluctuation is needed.
Case 5
Mr IR is a 62 year old man with a history of aortic stenosis, osteoporosis, vertebral fractures, depression, and alcohol dependence. He was admitted with back pain that had not responded to increased analgesia at home. A lumbar spine X-ray showed a likely new vertebral fracture.
Mr IR was treated with increased opioid analgesia with some effect.
Four days after admission the nursing staff noted that Mr IR was expressing suspicious thoughts about the care he was receiving. Also he had appeared mildly confused and irritable at the times during the night.
He was reviewed in more detail. During the consultation he appeared unhappy and distrustful. He said that strange things had been going on overnight, with the nurses having a party and keeping the other patients from sleeping. He was angry about this and asked if he could be moved to a different ward. He also said that he had been given the wrong drugs and that he was concerned that this He denied experiencing hallucinations.
A 4AT is performed.
ITEM 1 – Level of alertness: score 0 (normal)
ITEM 2 – AMT4: score 0 (all correct)
ITEM 3 – Months Backwards: score 0 (correct)
ITEM 4 – Acute change or fluctuation: score 4 (evidence of change from nurses, and also deduced as new paranoid thoughts likely to be acute)
4AT total score: 4/12
The score of 4 indicates possible delirium. In the present case this is based on the evidence of change alone.
In delirium there is usually has evidence of inattention and other cognitive deficits on one-off bedside testing. However it is well known in clinical practice that in some cases of delirium patients may have periods of being orientated and may even only have mild inattention that is not detectable by brief cognitive tests. Cognitive deficits in delirium can fluctuate, and a one-off bedside testing episode may not yield a positive score.
In the present case the history and the paranoid thoughts clearly indicate a high risk of delirium requiring intervention. The potential causes include opioid toxicity, pain, and alcohol withdrawal.
The 4AT is designed to allow likely delirium to be diagnosed in cases like this, even when cognitive deficits at the moment of assessment are not diagnostic.
Case 6
Mr EB is an 92 year man who lives in a residential home. He had a history of Alzheimer’s dementia, falls, and hypertenion. The paramedics were called to see Mr EB because of severe lethargy and reduced responsiveness. The history from residential home staff was fatigue over a 3 week period, and in the last 48 hours worsening drowsiness and reduced responsiveness. He also had a reduced appetite and reduced fluid intake for approximately 36 hours. Mr EB was normally mobile with assistance and had normal fluid and food intake.
The staff did not report any signs of distress in Mr EB.
A 4AT is performed. On entry into Mr EB’s room he was asleep, but he did open his eyes to speech and was able to give some meaningful answers. However when the tester stopped speaking he closed his eyes and appeared to be dozing. He denied hallucinations and there was no evidence of delusions.
4AT scoring:
ITEM 1 – Level of alertness: score 4 (clearly abnormal level of alertness)
ITEM 2 – AMT4: score 2 (knew place, age but unable to give year, date of birth)
ITEM 3 – Months Backwards: score 1 (said ‘December’ but unable to say any other months)
ITEM 4 – Acute change or fluctuation: score 4 (clear evidence of change from informant)
4AT total score: 11/12
This case shows delirium, with bedside signs including altered level of alertness, and some cognitive impairment. The history clearly indicates acute change.