The 4AT, a rapid delirium detection tool for use in hospice inpatient units: Findings from a validation study.

BACKGROUND: Delirium is a serious neuropsychiatric syndrome with adverse outcomes, which is common but often undiagnosed in terminally ill people. The 4 'A's test or 4AT (www.the4AT.com), a brief delirium detection tool, is widely used in general settings, but validation studies in terminally ill people are lacking. AIM: To determine the diagnostic accuracy of the 4AT in detecting delirium in terminally ill people, who are hospice inpatients. DESIGN: A diagnostic test accuracy study in which participants underwent the 4AT and a reference standard based on the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. The reference standard was informed by Delirium Rating Scale Revised-98 and tests assessing arousal and attention. Assessments were conducted in random order by pairs of independent raters, blinded to the results of the other assessment. SETTING/PARTICIPANTS: Two hospice inpatient units in Scotland, UK. Participants were 148 hospice inpatients aged ⩾18 years. RESULTS: A total of 137 participants completed both assessments. Three participants had an indeterminate reference standard diagnosis and were excluded, yielding a final sample of 134. Mean age was 70.3 (SD = 10.6) years. About 33% (44/134) had reference standard delirium. The 4AT had a sensitivity of 89% (95% CI 79%-98%) and a specificity of 94% (95% CI 90%-99%). The area under the receiver operating characteristic curve was 0.97 (95% CI 0.94-1). CONCLUSION: The results of this validation study support use of the 4AT as a delirium detection tool in hospice inpatients, and add to the literature evaluating methods of delirium detection in palliative care settings. TRIAL REGISTRY: ISCRTN 97417474.

IMPACT-Global Hip Fracture Audit: Nosocomial infection, risk prediction and prognostication, minimum reporting standards and global collaborative audit: Lessons from an international multicentre study of 7,090 patients conducted in 14 nations during the COVID-19 pandemic.

AIMS: This international study aimed to assess: 1) the prevalence of preoperative and postoperative COVID-19 among patients with hip fracture, 2) the effect on 30-day mortality, and 3) clinical factors associated with the infection and with mortality in COVID-19-positive patients. METHODS: A multicentre collaboration among 112 centres in 14 countries collected data on all patients presenting with a hip fracture between 1st March-31st May 2020. Demographics, residence, place of injury, presentation blood tests, Nottingham Hip Fracture Score, time to surgery, management, ASA grade, length of stay, COVID-19 and 30-day mortality status were recorded. RESULTS: A total of 7090 patients were included, with a mean age of 82.2 (range 50-104) years and 4959 (69.9%) being female. Of 651 (9.2%) patients diagnosed with COVID-19, 225 (34.6%) were positive at presentation and 426 (65.4%) were positive postoperatively. Positive COVID-19 status was independently associated with male sex (odds ratio (OR) 1.38, p = 0.001), residential care (OR 2.15, p < 0.001), inpatient fall (OR 2.23, p = 0.003), cancer (OR 0.63, p = 0.009), ASA grades 4 (OR 1.59, p = 0.008) or 5 (OR 8.28, p < 0.001), and longer admission (OR 1.06 for each increasing day, p < 0.001). Patients with COVID-19 at any time had a significantly lower chance of 30-day survival versus those without COVID-19 (72.7% versus 92.6%, p < 0.001). COVID-19 was independently associated with an increased 30-day mortality risk (hazard ratio (HR) 2.83, p < 0.001). Increasing age (HR 1.03, p = 0.028), male sex (HR 2.35, p < 0.001), renal disease (HR 1.53, p = 0.017), and pulmonary disease (HR 1.45, p = 0.039) were independently associated with a higher 30-day mortality risk in patients with COVID-19 when adjusting for confounders. CONCLUSION: The prevalence of COVID-19 in hip fracture patients during the first wave of the pandemic was 9%, and was independently associated with a three-fold increased 30-day mortality risk. Among COVID-19-positive patients, those who were older, male, with renal or pulmonary disease had a significantly higher 30-day mortality risk.

The 4 'A's test for detecting delirium in acute medical patients: a diagnostic accuracy study.

BACKGROUND: Delirium is a common and serious neuropsychiatric syndrome, usually triggered by illness or drugs. It remains underdetected. One reason for this is a lack of brief, pragmatic assessment tools. The 4 'A's test (Arousal, Attention, Abbreviated Mental Test - 4, Acute change) (4AT) is a screening tool designed for routine use. This project evaluated its usability, diagnostic accuracy and cost. METHODS: Phase 1 - the usability of the 4AT in routine practice was measured with two surveys and two qualitative studies of health-care professionals, and a review of current clinical use of the 4AT as well as its presence in guidelines and reports. Phase 2 - the 4AT's diagnostic accuracy was assessed in newly admitted acute medical patients aged ≥ 70 years. Its performance was compared with that of the Confusion Assessment Method (CAM; a longer screening tool). The performance of individual 4AT test items was related to cognitive status, length of stay, new institutionalisation, mortality at 12 weeks and outcomes. The method used was a prospective, double-blind diagnostic test accuracy study in emergency departments or in acute general medical wards in three UK sites. Each patient underwent a reference standard delirium assessment and was also randomised to receive an assessment with either the 4AT (n = 421) or the CAM (n = 420). A health economics analysis was also conducted. RESULTS: Phase 1 found evidence that delirium awareness is increasing, but also that there is a need for education on delirium in general and on the 4AT in particular. Most users reported that the 4AT was useful, and it was in widespread use both in the UK and beyond. No changes to the 4AT were considered necessary. Phase 2 involved 785 individuals who had data for analysis; their mean age was 81.4 (standard deviation 6.4) years, 45% were male, 99% were white and 9% had a known dementia diagnosis. The 4AT (n = 392) had an area under the receiver operating characteristic curve of 0.90. A positive 4AT score (> 3) had a specificity of 95% [95% confidence interval (CI) 92% to 97%] and a sensitivity of 76% (95% CI 61% to 87%) for reference standard delirium. The CAM (n = 382) had a specificity of 100% (95% CI 98% to 100%) and a sensitivity of 40% (95% CI 26% to 57%) in the subset of participants whom it was possible to assess using this. Patients with positive 4AT scores had longer lengths of stay (median 5 days, interquartile range 2.0-14.0 days) than did those with negative 4AT scores (median 2 days, interquartile range 1.0-6.0 days), and they had a higher 12-week mortality rate (16.1% and 9.2%, respectively). The estimated 12-week costs of an initial inpatient stay for patients with delirium were more than double the costs of an inpatient stay for patients without delirium (e.g. in Scotland, £7559, 95% CI £7362 to £7755, vs. £4215, 95% CI £4175 to £4254). The estimated cost of false-positive cases was £4653, of false-negative cases was £8956, and of a missed diagnosis was £2067. LIMITATIONS: Patients were aged ≥ 70 years and were assessed soon after they were admitted, limiting generalisability. The treatment of patients in accordance with reference standard diagnosis limited the ability to assess comparative cost-effectiveness. CONCLUSIONS: These findings support the use of the 4AT as a rapid delirium assessment instrument. The 4AT has acceptable diagnostic accuracy for acute older patients aged > 70 years. FUTURE WORK: Further research should address the real-world implementation of delirium assessment. The 4AT should be tested in other populations. TRIAL REGISTRATION: Current Controlled Trials ISRCTN53388093. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 40. See the NIHR Journals Library website for further project information. The funder specified that any new delirium assessment tool should be compared against the CAM, but had no other role in the study design or conduct of the study.

Delirium is the sudden onset of confusion that can happen when someone is unwell. It is common in older people who go into hospital, and it is upsetting for both the patients and their families. Delirium is important to diagnose, because people with delirium do less well than those without, and it is often treatable. The ideal way to diagnose delirium is with a full assessment by a specialist, but this is expensive and time-consuming. We therefore developed a short test called the 4 'A's Test (4AT). The four 'A's stand for Arousal, Attention, Abbreviated Mental Test ­ 4, and Acute change. First, we interviewed hospital staff about delirium and the 4AT. We found that the 4AT was already widely used and that people found it easy to use. We then tested how the 4AT performed in practice. A total of 785 recently admitted patients aged ≥ 70 years participated, of whom around one in eight had delirium. A researcher carried out the full standard delirium assessment on each patient and then a different researcher carried out the 4AT. A normal 4AT score reliably ruled out delirium. An abnormal score was also reasonably effective in detecting delirium, but staff still needed to follow up such patients with a full assessment. People with higher 4AT scores stayed in hospital longer and were more likely to die, and their treatment was more expensive. We conclude that the 4AT is a useful test to rule out delirium or to see if more detailed testing is required. It could help treat patients correctly and quickly. This would save money and improve outcomes.

Protocol for validation of the 4AT, a rapid screening tool for delirium: a multicentre prospective diagnostic test accuracy study.

INTRODUCTION: Delirium is a severe neuropsychiatric syndrome of rapid onset, commonly precipitated by acute illness. It is common in older people in the emergency department (ED) and acute hospital, but greatly under-recognised in these and other settings. Delirium and other forms of cognitive impairment, particularly dementia, commonly coexist. There is a need for a rapid delirium screening tool that can be administered by a range of professional-level healthcare staff to patients with sensory or functional impairments in a busy clinical environment, which also incorporates general cognitive assessment. We developed the 4 'A's Test (4AT) for this purpose. This study's primary objective is to validate the 4AT against a reference standard. Secondary objectives include (1) comparing the 4AT with another widely used test (the Confusion Assessment Method (CAM)); (2) determining if the 4AT is sensitive to general cognitive impairment; (3) assessing if 4AT scores predict outcomes, including (4) a health economic analysis. METHODS AND ANALYSIS: 900 patients aged 70 or over in EDs or acute general medical wards will be recruited in three sites (Edinburgh, Bradford and Sheffield) over 18 months. Each patient will undergo a reference standard delirium assessment and will be randomised to assessment with either the 4AT or the CAM. At 12 weeks, outcomes (length of stay, institutionalisation and mortality) and resource utilisation will be collected by a questionnaire and via the electronic patient record. ETHICS AND DISSEMINATION: Ethical approval was granted in Scotland and England. The study involves administering tests commonly used in clinical practice. The main ethical issues are the essential recruitment of people without capacity. Dissemination is planned via publication in high impact journals, presentation at conferences, social media and the website www.the4AT.com. TRIAL REGISTRATION NUMBER: ISRCTN53388093; Pre-results.

Cerebrospinal fluid cortisol levels are higher in patients with delirium versus controls.

BACKGROUND: High plasma cortisol levels can cause acute cognitive and neuropsychiatric dysfunction, and have been linked with delirium. CSF cortisol levels more closely reflect brain exposure to cortisol, but there are no studies of CSF cortisol levels in delirium. In this pilot study we acquired CSF specimens at the onset of spinal anaesthesia in patients undergoing hip fracture surgery, and compared CSF and plasma cortisol levels in delirium cases versus controls. FINDINGS: Delirium assessments were performed the evening before or on the morning of operation with a standard battery comprising cognitive tests, mental status assessments and the Confusion Assessment Method. CSF and plasma samples were obtained at the onset of the operation and cortisol levels measured. Twenty patients (15 female, 5 male) aged 62 - 93 years were studied. Seven patients were diagnosed with delirium. The mean ages of cases (81.4 (SD 7.2)) and controls (80.5 (SD 8.7)) were not significantly different (p = 0.88). The median (interquartile range) CSF cortisol levels were significantly higher in cases (63.9 (40.4-102.1) nmol/L) than controls (31.4 (21.7-43.3) nmol/L; Mann-Whitney U, p = 0.029). The median (interquartile range) of plasma cortisol was also significantly higher in cases (968.8 (886.2-1394.4) nmol/L, than controls (809.4 (544.0-986.4) nmol/L; Mann Whitney U, p = 0.036). CONCLUSIONS: These findings support an association between higher CSF cortisol levels and delirium. This extends previous findings linking higher plasma cortisol and delirium, and suggests that more definitive studies of the relationship between cortisol levels and delirium are now required.