The Delirium Rating Scale in a psychogeriatric inpatient setting

Delirium diagnosis methodology used in research: a survey-based study

OBJECTIVE

To describe methodology used to diagnose delirium in research studies evaluating delirium detection tools.

METHODS

The authors used a survey to address reference rater methodology for delirium diagnosis, including rater characteristics, sources of patient information, and diagnostic process, completed via web or telephone interview according to respondent preference. Participants were authors of 39 studies included in three recent systematic reviews of delirium detection instruments in hospitalized patients.

RESULTS

Authors from 85% (N = 33) of the 39 eligible studies responded to the survey. The median number of raters per study was 2.5 (interquartile range: 2-3); 79% were physicians. The raters' median duration of clinical experience with delirium diagnosis was 7 years (interquartile range: 4-10), with 5% having no prior clinical experience. Inter-rater reliability was evaluated in 70% of studies. Cognitive tests and delirium detection tools were used in the delirium reference rating process in 61% (N = 21) and 45% (N = 15) of studies, respectively, with 33% (N = 11) using both and 27% (N = 9) using neither. When patients were too drowsy or declined to participate in delirium evaluation, 70% of studies (N = 23) used all available information for delirium diagnosis, whereas 15% excluded such patients.

CONCLUSION

Significant variability exists in reference standard methods for delirium diagnosis in published research. Increasing standardization by documenting inter-rater reliability, using standardized cognitive and delirium detection tools, incorporating diagnostic expert consensus panels, and using all available information in patients declining or unable to participate with formal testing may help advance delirium research by increasing consistency of case detection and improving generalizability of research results.

Tools to detect delirium superimposed on dementia: a systematic review

OBJECTIVES

To identify valid tools to diagnose delirium superimposed on dementia.

DESIGN

Systematic review of studies of delirium tools that explicitly included individuals with dementia.

SETTING

Hospital.

PARTICIPANTS

Studies were included if delirium assessment tools were validated against standard criteria, and the presence of dementia was assessed according to standard criteria that used validated instruments.

MEASUREMENTS

PubMed, Embase, and Web of Science databases were searched for articles in English published between January 1960 and January 2012.

RESULTS

Nine studies fulfilled the selection criteria. Of 1,569 participants, 401 had dementia, and 50 had delirium superimposed on dementia. Six delirium tools were evaluated. One study using the Confusion Assessment Method (CAM) with 85% of participants with dementia had high specificity (96-100%) and moderate sensitivity (77%). Two intensive care unit studies that used the CAM for the Intensive Care Unit (CAM-ICU) reported 100% sensitivity and specificity for delirium in 23 individuals with dementia. One study using electroencephalography reported sensitivity of 67% and specificity of 91% in a population with a 100% prevalence of dementia. No studies examined potential effects of dementia severity or subtype on diagnostic accuracy.

CONCLUSIONS

The evidence base on tools for detection of delirium superimposed on dementia is limited, although some existing tools show promise. Further studies of existing or refined tools with larger samples and more-detailed characterization of dementia are required to address the identification of delirium superimposed on dementia.

Paliperidone in the treatment of delirium: results of a prospective open-label pilot trial

Yoon H-K, Kim Y-K, Han C, Ko Y-H, Lee H-J, Kwon D-Y, Kim L. Paliperidone in the treatment of delirium: results of a prospective open-label pilot trial.

Objective: Delirium is a life-threatening neuropsychiatric syndrome characterised by disturbances in consciousness, attention, cognition and perception. Antipsychotics are considered the drugs of choice in managing the symptoms of delirium. Paliperidone is a benzisoxazole derivative and the principal active metabolite of risperidone. In this study, we aimed to evaluate the efficacy of paliperidone for the treatment of delirium.

Methods: A prospective open-label study of paliperidone for delirium treatment was performed with 6-day follow-up. Fifteen patients who met Diagnostic and Statistical Manual of Mental disorders, Fourth Edition criteria for delirium and had a score of 13 on the Delirium Rating Scale were recruited. The starting dose was 3 mg once a day and the dose was adjusted depending on the status of delirium. Daily assessments of the severity of delirium were evaluated using Memorial Delirium Assessment Scale (MDAS).

Results: The mean daily maintenance dose of paliperidone was 3.75 ± 1.06. The MDAS scores before and after treatment (day 7) were 23.60 ± 6.31 and 11.33 ± 5.45 (t = 6.78, p < 0.001), respectively. The intensity of delirium showed a statistically significant reduction in MDAS scores from the first day of treatment. No serious adverse effects were observed, and none of the patients discontinued paliperidone because of adverse effects.

Conclusions: This study shows that low-dose paliperidone is effective in reducing behavioural disturbances and symptoms in delirium and is well tolerated in delirious patients. This trial is an open-label study with a small sample size, and further controlled studies will be necessary.

On the utility of diagnostic instruments for pediatric delirium in critical illness: an evaluation of the Pediatric Anesthesia Emergence Delirium Scale, the Delirium Rating Scale 88, and the Delirium Rating Scale-Revised R-98

Purpose

Delirium is a poor-prognosis neuropsychiatric disorder. Pediatric delirium (PD) remains understudied, particularly at pediatric intensive care units (PICU). Although the Pediatric Anesthesia Emergence Delirium (PAED) scale, the Delirium Rating Scale (DRS-88), and the Delirium Rating Scale-Revised (DRS-R-98) are available, none have been validated for use in PICU settings. The aim of the present study was to investigate the use of the DRS/PAED instruments as diagnostic tools for PD in the PICU.

Methods

A prospective panel study was conducted, under circumstances of routine clinical care, investigating the diagnostic properties of the PAED, DRS-88, and DRS-R-98 in PICU patients at a tertiary university medical center. A total of 182 non-electively admitted, critically ill pediatric patients, aged 1–17 years, were included between November 2006 and February 2010. Sensitivity, specificity, and receiver operating characteristic (ROC) curves were calculated. Three psychometric properties were analyzed: (1) internal consistency (2) proportion of items not rateable, and (3) discriminative ability.

Results

The PAED could be completed in 144 (93.5%) patients, much more frequently than either the DRS-88 (66.9%) or the DRS-R-98 (46.8%). Compared with the clinical gold standard diagnosis of delirium, the PAED had a sensitivity of 91% and a specificity of 98% (AUC 0.99). The optimal PAED cutoff score as a screening instrument in this PICU setting was 8. Cronbach’s alpha was 0.89; discriminative ability was high.

Conclusions

The PAED is a valid instrument for PD in critically ill children, given its reliance on routinely rateable observational signs and symptoms.

Korean version of the delirium rating scale-revised-98: reliability and validity

OBJECTIVE

The aims of the present study were 1) to standardize the validity and reliability of the Korean version of Delirium Rating Scale-Revised-98 (DRS-R98-K) and 2) to establish the optimum cut-off value, sensitivity, and specificity for discriminating delirium from other non-delirious psychiatric conditions.

METHODS

Using DSM-IV criteria, 157 subjects (69 delirium, 29 dementia, 32 schizophrenia, and 27 other psychiatric patients) were enrolled. Subjects were evaluated using DRS-R98-K, DRS-K, Mini-Mental State Examination (MMSE-K), and Clinical Global Impression-Severity (CGI-S) scale.

RESULTS

DRS-R98-K total and severity scores showed high correlations with DRS-K. They were significantly different across all groups (p=0.000). However, neither MMSE-K nor CGI-S distinguished delirium from dementia. All DRS-R98-K diagnostic items (#14-16) and items #1 and 2 significantly discriminated delirium from dementia. Cronbach's alpha coefficient revealed high internal consistency for DRS-R98-K total (r=0.91) and severity (r=0.89) scales. Interrater reliability (ICC between 0.96 and 1) was very high. Using receiver operating characteristic analysis, the area under the curve of DRS-R98-K total score was 0.948 between the delirium group and all other groups and 0.873 between the delirium and dementia groups. The best cut-off scores in DRS-R98-K total score were 18.5 and 19.5 between the delirium and the other three groups and 20.5 between the delirium and dementia groups.

CONCLUSION

We demonstrated that DRS-R98-K is a valid and reliable instrument for assessing delirium severity and diagnosis and discriminating delirium from dementia and other psychiatric disorders in Korean patients.

Delirium scales: A review of current evidence

OBJECTIVES

Delirium is a common neuropsychiatric condition with many adverse outcomes in elderly populations including death. Despite this, it is often misdiagnosed and mistreated. A number of scales can be used to detect delirium. We review scales that have been used in delirium studies and report their psychometric properties.

METHOD

An extensive MEDLINE database search and subsequent examination of reference lists was conducted to identify the various delirium scales that have been designed, primarily for use in the elderly.

RESULTS

Twenty-four scales were identified. Delirium instruments differed according to the classification system they were based on, length of time to administer, the rater and whether they were screening scales or measured symptom severity. The psychometric properties of each scale is reported.

CONCLUSION

A large number of scales exist, but not all are properly evaluated in terms of psychometric properties, and there is not unanimity about which scale is the best. However, a small number of scales may be considered already to be robust and useable: the CAM, the DRS, the MDAS and the NEECHAM.

Assessment scales for delirium

Delirium is a severe psychiatric syndrome that is highly prevalent in elderly general hospital patients. However, the diagnosis of delirium is often missed. The use of rating scales can be helpful in detecting and measuring delirium symptom severity. This article reviews recent developments regarding psychometric qualities, measurement goals, content and rating procedures of some of the available rating scales in clinical practice. Literature from the Medline files up to 2008 were collected, using the following search entries: delirium, (acute) confusion, assessment/rating scale and screening. Articles were selected if their title or summary were related to the development or applicability of delirium rating scales. The reference lists of relevant articles were searched for additional references. The rating scales were split up according to their purposes, screening or severity rating and were discussed for the following aspects: content (theoretical background, rating domains and items), interview (duration, format and assessors’ expertise) and psychometric qualities (reliability and validity). There were eight screening scales (Confusion Assessment Method [CAM], CAM for the Intensive Care Unit [CAM-ICU], Intensive Care Delirium Screening Checklist [ICDSC], Delirium Symptom Interview [DSI], NEECHAM Confusion Scale [NEECHAM], Cognitive Test for Delirium [CTD], Delirium Observation Screening [DOS] and Nursing Delirium Screening Scale [Nu-DESC]) and seven severity rating scales (Delirium Rating Scales [DRS], Memorial Delirium Assessment Scales [MDAS], Confusional State Evaluation [CSE], Delirium Severity Scales [DSS], Delirium Index [DI], Delirium-O-Meter [DOM] and Delirium Detection Scale [DDS] ) selected for further research. The CAM, NEECHAM and DOS and the CAM-ICU for the ICU appear to be the most suitable as screening instruments, depending on the type of rater (trained) physician or nurse. The (revised) Delirium Rating Scale (DRS-R-98) and the DOM appear to be particularly useful for measuring delirium severity or monitoring change.

Phenomenology of delirium in cancer patients, as described by the Memorial Delirium Assessment Scale (MDAS) and the Delirium Rating Scale (DRS)

This study was based on the data collected on a consecutive sample of 106 cancer patients referred for mental status evaluation. All patients were evaluated by use of the Confusion Assessment Method (CAM) algorithm, the Delirium Rating Scale (DRS), the Memorial Delirium Assessment Scale (MDAS), and a question about the subjective perception of delirium. After comparing the diagnostic criteria of delirium on the DSM-III-R and DSM-IV, authors evaluated the ability of all DRS and MDAS items to discriminate delirium versus non-delirium patients, testing the difference in the distribution of the individual MDAS and DRS item scores. Authors also assessed the relationship between delirium diagnosis and the subjective perception of delirium. The MDAS showed a greater number of discriminating items. The items that proved to be less discriminating were "Hallucinations" and "Lability of Mood" on the DRS. Subjective perception only partially discriminated delirium from non-delirium patients. The way in which the DRS and MDAS reflected the DSM criteria are therefore partially different.

Inter-Rater Reliability of Delirium Rating Scales

Delirium continues to be under-recognized despite use of rating scales with apparently high inter-rater reliability. We analyzed the inter-reliability data of published rating scales for delirium using a standard questionnaire to evaluate if the inter-rater reliability was assessed rigorously. Most studies employed a heterogeneous group of cognitively disordered elderly, however other aspects of inter-rater reliability estimation were less than rigorous. This suggests that the reported reliability may be spuriously high, which may have implications on the ability of clinicians to discriminate delirium from other causes of cognitive impairment in practice. The methodology of assessing inter-rater reliability of delirium scales needs to improve and reliability should be evaluated when the settings of administration change substantially.

Cognitive Impairment after Stroke – Impact on Activities of Daily Living and Costs of Care for Elderly People

BACKGROUND AND PURPOSE

The economic burden of stroke is substantial and is likely to increase with an increasing number of elderly individuals in the population. There is thus a need for information on the use of health care resources and costs among these elderly stroke patients. We examined the impact of the cognitive impairments on the ability to perform activities of daily living (ADL) and utilization and costs of health care in a cohort of elderly stroke patients.

METHODS

One hundred and forty-nine patients aged >/=70 years with acute stroke were included. The patients were assessed regarding their ability to carry out ADL and health resource utilization and cost during the first year after stroke. Cognitive impairments were assessed 18 months after the index stroke.

RESULTS

Stroke severity in acute stroke and cognitive impairment at 18 months after stroke onset was associated with impairment in ADL and increased costs for utilisation of care during the first year. Patients with cognitive impairment were more dependent on personal assistance in ADL. Costs per patient during the study were three times higher for patients with cognitive impairment. Hospital care, institutional living and different kinds of support from society accounted for the highest costs.

CONCLUSIONS

Costs of care utilisation during the first year after stroke were associated with cognitive impairments, stroke severity and dependence in ADL. The results should be interpreted cautiously as the assessment of cognitive function was made 18 months after stroke onset and costs were estimated for the first year after stroke.

A double-blind trial of risperidone and haloperidol for the treatment of delirium

To compare the clinical efficacy of haloperidol and risperidone for the treatment of delirium, the authors performed a double-blind comparative study. Twenty-eight patients with delirium were recruited and randomly assigned to receive a flexible-dose regimen of haloperidol or risperidone over 7 days. The severity of delirium was assessed by using Memorial Delirium Assessment Scale scores. Scores for each group decreased significantly over the study period. However, no significant differences in mean Memorial Delirium Assessment Scale scores between groups were found. The group-by-time effect was not significant. In addition, there was no significant difference in the frequency of response to the drugs between the two groups. One patient in the haloperidol group experienced mild akathisia, but no other patients reported clinically significant side effects. These data show no significant difference in the efficacy or response rate between haloperidol and risperidone in the treatment of delirium.

The measurement of delirium: review of scales

This review describes the characteristics and evaluates the psychometric qualities (process of testing and the results) of thirteen delirium instruments. Delirium instruments differ in goal (diagnosis, screening symptoms severity), type of data on which the rating is based (observation, interview or test of patients), the rater qualities required, the number of items and the rating time needed. Most instruments are based on the Diagnostic Statistical Manual criteria and measure signs and symptoms as described by these criteria. Reliability of delirium instruments shows good to excellent results. Validity of the delirium instruments is overall fair to good. Differences exist, however, in the degree to which reliability and validity were tested and the quality of the testing procedures. Most instruments are not further developed and tested after the initial study. Conclusion of this review is that most delirium instruments show promising results but need further testing. Testing is needed in different samples and on a broader range of aspects with regard to reliability and validity. Much emphasis should be given to the procedures used in future studies. Ease of use is an aspect of testing that is so far not taken into account, however, is important for use of instruments in clinical practice. A minority of instruments can be seen as "ready to use" instruments meaning well tested in more than one sample with good results. For screening high-risk, elderly hospitalized patients, the NEECHAM Confusion Scale and the Delirium Observation Screening Scale are recommended. The Confusion Assessment Method is the best diagnostic tool and the Delirium Rating Scale shows best results in screening symptom severity. For ICU patients the CAM-ICU is recommended. The MDAS is well tested in cancer patients. Nurses, however, have not yet tested the DRS and MDAS in practice.

Psychosis in Alzheimer disease: postmortem magnetic resonance spectroscopy evidence of excess neuronal and membrane phospholipid pathology

BACKGROUND

The presence of psychotic symptoms in Alzheimer Disease subjects (AD+psychosis, AD+P) is a marker for a phenotype characterized by more severe cognitive impairment and a more rapidly deteriorating course. Although AD+P has been inconsistently associated with more severe neuropathology, no prior studies have examined measures of neuronal and synaptic integrity.

OBJECTIVE

To determine whether AD+P is associated with evidence of disrupted neuronal and synaptic integrity, as indicated by magnetic resonance spectroscopy (MRS) measurement of N-acetyl-L-aspartate and the membrane breakdown products, glycerophosphocholine and glycerophosphoethanolamine.

METHODS

31P and 1H MRS studies of perchloric acid extract from postmortem brain of AD subjects with and without a history of psychotic symptoms. All subjects were characterized for the presence of comorbid cortical Lewy body pathology and for history of neuroleptic use. Brain tissue from dorsolateral prefrontal, superior temporal, inferior parietal, and occipital cortex, amygdala, and cerebellum were examined in all subjects. Statistical analysis accounted for correlated observations across brain regions within-subjects.

RESULTS

AD+P subjects demonstrated significant elevations of glycerophosphoethanolamine and significant reductions of N-acetyl-L-aspartate. Between group differences were greatest in neocortical brain regions.

CONCLUSION

Excess impairment of neocortical neuronal and synaptic integrity may provide the structural substrate underlying AD+P. Confirmation of these findings using in vivo MRS measures is indicated.

Studying acute confusion in long-term care: clinical investigation or secondary data analysis using the minimum data set?

Clinical investigations of acute confusion have largely been initiated in the acute care setting, where no uniform patient assessment exists. No reliable estimates of the prevalence of acute confusion in long-term care (LTC) residents have been reported. Delirium indicators are present in the nursing home Minimum Data Set (MDS), suggesting that MDS assessments could be used to facilitate studies of acute confusion in LTC. Methods to study acute confusion in LTC are discussed, with an emphasis on the advantages and disadvantages of using secondary analysis of MDS assessments as one research strategy.

Delirium in psychiatric inpatients: a case-control study

OBJECTIVE

To investigate the clinical and pharmacoepidemiological determinants of delirium in a psychiatric inpatient population.

METHOD

A case-control study design was used. Potential cases and potential controls were identified using hospital discharge data. The clinical record of each subject was reviewed using a validated protocol to confirm case and control status. Subsequently, exposure data were recorded from clinical records.

RESULTS

Subjects admitted to hospital with delirium tended to be older, to have pre-existing cognitive deficits, and to have diagnoses of substance use disorders. Subjects who developed delirium after their admission to hospital were older than control subjects, more likely to have a history of cognitive impairment, and were significantly more likely to be treated during the hospitalization with lithium or anticholinergic antiparkinsonian medications. Antipsychotic medication exposures were also associated with delirium, but only at standard or above-standard dosage levels. Antidepressant and sedative-hypnotic medications were not associated with delirium.

CONCLUSIONS

These findings indicate that using conservative dosages of antipsychotic medications and minimizing the use of anticholinergic medications for parkinsonian symptoms may help to prevent delirium in psychiatric inpatients. Anticonvulsant mood stabilizers may convey less delirium risk than lithium. Antidepressant medications and sedative-hypnotics were not important determinants of delirium in this population.

Assessing delirium in cancer patients: the Italian versions of the Delirium Rating Scale and the Memorial Delirium Assessment Scale

To validate the Italian versions of the Delirium Rating Scale (DRS) and the Memorial Delirium Assessment Scale (MDAS), 105 cancer patients consecutively referred for neurological or psychiatric consultation for mental status change were evaluated using the Confusion Assessment Method (CAM), the DRS, the MDAS, and the Mini-Mental State Examination (MMSE). According to the CAM criteria and clinical examination, 66 patients were delirious, and 39 received diagnoses other than delirium. The DRS and the MDAS scores significantly distinguished delirious from non-delirious patients. The MDAS and the DRS were mutually correlated. When using the proposed cut-off scores for the two scales, the MDAS had higher specificity (94%) but lower sensitivity (68%) than the DRS (sensitivity = 95%, specificity = 61% for DRS cut-off 10; sensitivity = 80%, specificity = 76%, DRS cut-off 12). The MMSE showed high sensitivity (96%) and very low specificity (38%). Exploratory factor analysis of the DRS and the MDAS suggested a three-factor and two-factor structure, respectively. Both instruments in their Italian version proved to be useful for the assessment of delirium among cancer patients. Further research is needed to examine the use of the DRS and the MDAS in other clinical contexts.

The Delirium Rating Scale. Its use in consultation-liaison research

In addition to diagnostic criteria, delirium research requires standardized instruments to measure symptoms. This article reviews the literature about the Delirium Rating Scale (DRS), the most widely used scale to assess delirium that has been translated into at least seven other languages. The DRS has 10 items and is clinician-rated, but 7- or 8-item subscale adaptations have been used for repeated measurements. It has high scale characteristics, including internal consistency, validity, specificity, sensitivity and interrater reliability. The DRS distinguishes delirious from demented, schizophrenic, and depressed patients and is more accurate than cognitive tests in identifying delirium. Scores are sensitive to treatment of delirium. Principal components analyses find one underlying dimension that can be subdivided into two or three components. The DRS has been used in studies of phenomenology, physiology, treatment, outcome, and at-risk populations. Tables summarize details from various studies. The DRS is used clinically and in research. It is currently being revised to enhance its use in phenomenologic and treatment research.

Delirium. Advances in diagnosis, pathophysiology, and treatment

This article discusses research in the areas of morbidity and mortality, epidemiologic risk factors, phenomenology, pathophysiology, and treatment of delirium. Delirium assessment instruments are reviewed. The neuropathophysiologic understanding of delirium is discussed in the context of important CNS neural circuitry. Pharmacologic treatments of delirium in adults and children are outlined, with particular emphasis on intravenous use of butyrophenone neuroleptics.

Cross-validation of the Delirium Rating Scale in older patients

OBJECTIVE

To cross-validate the Delirium Rating Scale (DRS).

DESIGN

Cross-sectional.

SETTING

Geriatric medicine and geriatric psychiatry assessment units and consultation services.

PARTICIPANTS

A total of 104 older patients on the above services.

MEASUREMENTS

Mini-Mental State Examination (MMSE) score, Barthel Index score, DRS score, Blessed Dementia Scale score, clinical diagnoses using DSM-III-R criteria.

MAIN RESULTS

The mean DRS score was highest in the delirium group. Cronbach's alpha was .90, and inter-rater reliability of total scores was .91 (intra-class correlation). Receiver Operating Characteristic curve analysis showed that the area under the curve for the DRS was significantly higher than the MMSE as a test for delirium. At its published cutpoint of 10, the sensitivity of the DRS is .82 and the specificity is 94. The value at which the sensitivity of the DRS is .90 is 8, at which specificity is .82.

CONCLUSIONS

The DRS appears to a feasible instrument. In a sample with a high proportion of delirious patients, it has acceptable measurement properties when used by expert observers.

Validation of the Scale of Functioning in Older Outpatients With Schizophrenia

The authors investigated the reliability and validity of the Scale of Functioning (SOF), a 15-item scale, in 78 middle-aged and elderly outpatients with schizophrenia. The SOF score had both high internal consistency and high interrater reliability and significantly discriminated between these patients and 45 normal comparison subjects. SOF scores correlated significantly with scores on several psychopathology rating scales as well as a number of existing instruments assessing cognitive or functional ability. Principal-components analysis using different scales of functional ability, psychopathology, and global cognitive performance and treated by orthogonal rotation revealed two domains of functioning, one of which was defined by the SOF along with scales for activities of daily living, negative symptoms, and cognitive impairment. The other domain was defined by scales for quality of well-being, social adjustment, and positive and depressive symptoms. Results support the construct validity of the SOF in late-life schizophrenia.

Further analyses of the Delirium Rating Scale

The Delirium Rating Scale is a clinician-rated, 10-item symptom rating scale for assessment of delirium severity. In order to better understand the relationship between items of the scale and whether they reflect one or more underlying groupings or dimensions, further analyses of the originally published scale data were performed. Factor analysis revealed a strong single underlying dimension that could be further divided into two components: one comprising delusions, psychomotor behavior, cognition, sleep-wake cycle disturbance, and mood lability; the other comprising temporal onset of symptoms, perceptual disturbances, hallucinations, and fluctuation of symptoms. Implications for improved phenomenological understanding of delirium are discussed.

A review of delirium assessment instruments

This paper reviews various types of assessment instruments for delirium, including nursing screening scales, symptom checklists, an analog scale, an interview schedule, and symptom rating scales. Their structures and applicability to the clinical and research assessment of delirium are described. Despite the seeming plethora of assessment methods, only a few are suitable for use by researchers.