Delirium screening tools validated in the context of palliative care: A systematic review

Delirium detection in the emergency department: A diagnostic accuracy meta-analysis of history, physical examination, laboratory tests, and screening instruments

INTRODUCTION

Geriatric emergency department (ED) guidelines emphasize timely identification of delirium. This article updates previous diagnostic accuracy systematic reviews of history, physical examination, laboratory testing, and ED screening instruments for the diagnosis of delirium as well as test-treatment thresholds for ED delirium screening.

METHODS

We conducted a systematic review to quantify the diagnostic accuracy of approaches to identify delirium. Studies were included if they described adults aged 60 or older evaluated in the ED setting with an index test for delirium compared with an acceptable criterion standard for delirium. Data were extracted and studies were reviewed for risk of bias. When appropriate, we conducted a meta-analysis and estimated delirium screening thresholds.

RESULTS

Full-text review was performed on 55 studies and 27 were included in the current analysis. No studies were identified exploring the accuracy of findings on history or laboratory analysis. While two studies reported clinicians accurately rule in delirium, clinician gestalt is inadequate to rule out delirium. We report meta-analysis on three studies that quantified the accuracy of the 4 A's Test (4AT) to rule in (pooled positive likelihood ratio [LR+] 7.5, 95% confidence interval [CI] 2.7-20.7) and rule out (pooled negative likelihood ratio [LR-] 0.18, 95% CI 0.09-0.34) delirium. We also conducted meta-analysis of two studies that quantified the accuracy of the Abbreviated Mental Test-4 (AMT-4) and found that the pooled LR+ (4.3, 95% CI 2.4-7.8) was lower than that observed for the 4AT, but the pooled LR- (0.22, 95% CI 0.05-1) was similar. Based on one study the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is the superior instrument to rule in delirium. The calculated test threshold is 2% and the treatment threshold is 11%.

CONCLUSIONS

The quantitative accuracy of history and physical examination to identify ED delirium is virtually unexplored. The 4AT has the largest quantity of ED-based research. Other screening instruments may more accurately rule in or rule out delirium. If the goal is to rule in delirium then the CAM-ICU or brief CAM or modified CAM for the ED are superior instruments, although the accuracy of these screening tools are based on single-center studies. To rule out delirium, the Delirium Triage Screen is superior based on one single-center study.

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.

Accuracy of Delirium Screening Tools in Older People with Cancer-A Systematic Review

BACKGROUND

The increase in life expectancy worldwide has led to a larger population of older people, which in turn entails a rising prevalence of cancer. One of the main complications of cancer is delirium, especially in advanced stages.

OBJECTIVE

To determine which delirium screening instrument is the most accurate in older people with cancer.

METHODS

A systematic review was designed. A literature search was performed in MEDLINE, EBSCO and SCOPUS; additional records were identified by handsearching. Selection criteria were studies involving people with cancer and a mean sample age of 60 years or older, assessing delirium, and reporting the metric properties of the assessment instrument. Studies with post-surgical patients and substance abuse delirium were excluded.

RESULTS

From 2001 to 2021, 14 eligible studies evaluated 13 different assessment tools, reporting an incidence of delirium ranging from 14.3% to 68.3%. The Delirium Observation Screening Scale (DOSS) showed the best metric properties, followed by the Nursing Delirium Screening Scale (NuDESC), Confusion Assessment Method (CAM) and Memorial Delirium Assessment Scale (MDAS). Only two studies were considered to be at low risk of bias using the QUADAS-2 Tool. No study exclusively examined this population group.

CONCLUSIONS

Screening tools for delirium are heterogeneous for older people with cancer, and there is a need to analyze metric properties exclusively in the older population. Registered on PROSPERO ID: CRD42022303530.

A simple risk score list can be used to predict the occurrence of delirium in patients admitted to inpatient hospice care: A medical record study

OBJECTIVE

This study aimed to examine whether the 10-item Risk Score List (RSL) accurately predicts delirium in patients admitted to inpatient hospice care and whether this instrument can be simplified. Determining the risk for developing delirium can help to treat these patients in a timely manner.

METHODS

This was a retrospective medical record study in patients who died in 2019 or 2020 in three hospices. Predictive values were examined using Cox regression analysis, crosstabs, and C-statistic.

RESULTS

In total, 240 patients were included. Median age at admission was 78 (IQR 70-84) years. Primary diagnosis most often was cancer (n = 186, 78%); 173 (72%) patients had an increased risk of delirium according to RSL, of whom 120 (69%) developed delirium. Overall, 147 (61%) patients developed delirium. The RSL significantly predicted future delirium (HR 3.25, CI 1.87-5.65, p < 0.01) and had a sensitivity of 85%, a specificity of 43%, positive predictive value of 62%, negative predictive value of 73%, and a C-statistic of 0.64. Simplifying the RSL to four items still significantly predicted future delirium, with similar predictive values.

CONCLUSION

Delirium occurs in more than half of patients admitted to hospice care. The RSL can be simplified to four items, without compromising on predictive accuracy.

The Dilemma of Treating Delirium: the Conundrum of Drug Management

OPINION STATEMENT

Delirium is a common medical complication in people living with cancer, particularly with more advanced disease. Delirium is associated with significant symptom burden which causes distress and impacts quality of life. As recommended by international guidelines, a high degree of suspicion is needed to ensure delirium is detected early. Attention to collateral history can provide clues to changes in cognition and attention. Non-pharmacological approaches that can be considered essential elements of care are effective in reducing the risk of delirium. Delirium screening using a validated measure is recommended as even expert clinicians can underdiagnose or miss delirium. The diagnostic assessment requires consideration of the cancer diagnosis and comorbidities, in the context of potential reversibility, goals of care, and patient preferences. The gold standard approach based on expert consensus is to institute management for delirium precipitants supported by non-pharmacological essential care, with the support of an interdisciplinary team. Medication management should be used sparingly and for a limited period of time wherever possible for severe perceptual disturbance or agitation which has not improved with non-pharmacological approaches. Clinicians should be familiar with the registered indication for medications and seek informed consent for off-label use. All interventions put in place to manage delirium need to consider net clinical benefit, including harms such as sedation and loss of capacity for meaningful interaction. Clear communication and explanation are needed regularly, with the person with delirium as far as possible and with surrogate decision makers. Delirium can herald a poor prognosis and this needs to be considered and be discussed as appropriate in shared decision-making. Recall after delirium has resolved is common, and opportunity to talk about this experience and the related distress should be offered during the period after recovery.

The detection of delirium in admitted oncology patients: a scoping review

Aim

To understand the validation of delirium detection tools in medical oncology, as well as identify data on incidence, prevalence and reversibility in this setting.

Findings

Of twelve studies, only four used case ascertainment methods following published recommendations, six studies had a low risk of bias.

Message

In delirium tool validation studies in the oncology setting, choice of appropriate gold standard for case ascertainment is a critical factor. New tools and new validations are not recommended, rather the critical application of existing tools depending on appropriate validation and clinical practicality for the setting.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41999-021-00586-1.

Purpose

Delirium leads to poor outcomes for patients and careers and has negative impacts on staff and service provision. Cancer rates in elderly populations are increasing and frequently, cancer diagnoses are a co-morbidity in the context of frailty. Data relating to the epidemiology of delirium in hospitalised cancer patients are limited. With the overarching purpose of improving delirium detection and reducing the morbidity and mortality of delirium in cancer patients, we reviewed the epidemiological data and approach to delirium detection in hospitalised, adult oncology patients.

Methods

MEDLINE, EMBASE, CINAHL, PsycINFO, and SCOPUS databases were searched from January 1996 to August 2017. Key concepts were delirium, cancer, inpatient oncology and delirium screening/detection.

Results

Of 896 unique studies identified; 91 met full-text review criteria. Of 12 eligible studies, four applied recommended case ascertainment methods to all patients, three used delirium screening tools alone or with case ascertainment tools sub-optimally applied, four used tools not recommended for delirium screening or case ascertainment, one used the Confusion Assessment Method with insufficient information to determine if it met case ascertainment status. Two studies presented delirium incidence rates: 7.8%, and 17% respectively. Prevalence rates ranged from 18–33% for general medical or oncology wards; 42–58% for Acute Palliative Care Units (APCU); and for older cancer patients: 22% and 57%. Three studies reported reversibility; 26% and 49% respectively (APCUs) and 30% (older patients with cancer). Six studies had a low risk of bias according to QUADAS-2 criteria; all studies in the APCU setting were rated at higher risk of bias. Tool selection, study flow and recruitment bias reduced study quality.

Conclusion

The knowledge base for improved interventions and clinical care for adults with cancer and delirium is limited by the low number of studies. A clear distinction between screening tools and diagnostic tools is required to provide an improved understanding of the rates of delirium and its reversibility in this population.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41999-021-00586-1.

The conscious state of the dying patient: An integrative review

OBJECTIVES

The cognitive state of the dying in the last days of life may deteriorate, resulting in a reduced ability to communicate their care needs. Distressing symptoms, physical and existential, may go unrecognized and untreated. The objectives of this integrative review were to systematically interrogate the literature to determine the changing conscious state of dying adults and to identify changes in their care needs.

METHODS

An integrative review protocol was registered with PROSPERO (CRD42020160475). The World Health Organization definition of palliative care informed the review. CINAHL, MEDLINE (OVID), Scopus, PsycINFO, Cochrane Library, and PubMed were searched from inception to October 2019 using search strategies for each database. Inclusion and exclusion criteria were applied. Methodological quality was appraised using the Joanna Briggs Institute Checklist for the Case Series appraisal tool. Extracted data were synthesized using a narrative approach.

RESULTS

Of 5,136 papers identified, 11 quantitative case series studies were included. Six themes were identified: conscious state and change over time, awareness, pain, absence of holistic care, the voiceless patient, and signs and symptoms of dying.

SIGNIFICANCE OF RESULTS

In the last days of life, the physical and conscious state of the dying patient declines, resulting in an inability to express their care needs. Dignity in dying and freedom from pain and suffering are both an imperative and a human right; and unvoiced care needs can result in unnecessary suffering and distress. This review revealed that little is known about how healthcare professionals assess holistic care needs at this vulnerable time. Although much has been written about palliative and end-of-life care, the assessment of care needs when patients are no longer able to voice their own needs has largely been ignored, with little attention from clinical, educational, or research perspectives. This gap in evidence has important implications for the dying and their families.

Symptom trajectories for palliative care inpatients with and without hyperactive delirium in the last week of life

AIMS

Hyperactive delirium (HD) is a common and distressing symptom among palliative care patients. This study aimed to describe the characteristics of HD and associated symptoms among palliative care inpatients and evaluate relationships between HD development and symptom trajectories in this population.

DESIGN

A retrospective study was conducted.

METHODS

A retrospective review of medical records was conducted for all patients who died in a large Australian specialist palliative care unit between 1 January and 31 December 2019. Patients were assessed daily using the Symptoms Assessment Scale (SAS) and Palliative Care Problem Severity Scale (PCPSS). Multilevel models were used to estimate the differences in symptoms trajectories in the last 7 days of life between the two groups.

RESULTS

Of the 501 included patients, 64.5% (323) had an episode of HD. For 30% (95) of patients, HD occurred prior to admission. Compared with patients without HD, those with HD had significantly higher odds ratios (ORs) for four of the seven SAS symptoms (sleep problems, appetite, fatigue and pain; OR range: 1.94-4.48, p < .05), and all four PCPSS items (OR range: 2.00-3.00, p < .05) in the last week of life.

CONCLUSIONS

Palliative care inpatients commonly experience HD in their last week of life. There are higher levels of symptom distress, complexity, psychological concerns and family/carer concerns among patients with HD compared with those without HD.

IMPACT

The high prevalence of HD, and its association with higher levels of symptom distress, highlights the importance of routine screening and optimal management for HD among palliative care patients. Given the widely recognized challenges facing palliative care professionals in assessment and management of delirium, provision of relevant training among these professionals is recommended.