A classification system for delirium subtyping with the use of a commercial mobility monitor

Rest-Activity Rhythm Differences in Acute Rehabilitation Between Poststroke Patients and Non-Brain Disease Controls: Comparative Study

BACKGROUND

Circadian rhythm disruptions are a common concern for poststroke patients undergoing rehabilitation and might negatively impact their functional outcomes.

OBJECTIVE

Our research aimed to uncover unique patterns and disruptions specific to poststroke rehabilitation patients and identify potential differences in specific rest-activity rhythm indicators when compared to inpatient controls with non-brain-related lesions, such as patients with spinal cord injuries.

METHODS

We obtained a 7-day recording with a wearable actigraphy device from 25 poststroke patients (n=9, 36% women; median age 56, IQR 46-71) and 25 age- and gender-matched inpatient control participants (n=15, 60% women; median age 57, IQR 46.5-68.5). To assess circadian rhythm, we used a nonparametric method to calculate key rest-activity rhythm indicators-relative amplitude, interdaily stability, and intradaily variability. Relative amplitude, quantifying rest-activity rhythm amplitude while considering daily variations and unbalanced amplitudes, was calculated as the ratio of the difference between the most active 10 continuous hours and the least active 5 continuous hours to the sum of these 10 and 5 continuous hours. We also examined the clinical correlations between rest-activity rhythm indicators and delirium screening tools, such as the 4 A's Test and the Barthel Index, which assess delirium and activities of daily living.

RESULTS

Patients who had a stroke had higher least active 5-hour values compared to the control group (median 4.29, IQR 2.88-6.49 vs median 1.84, IQR 0.67-4.34; P=.008). The most active 10-hour values showed no significant differences between the groups (stroke group: median 38.92, IQR 14.60-40.87; control group: median 31.18, IQR 18.02-46.84; P=.93). The stroke group presented a lower relative amplitude compared to the control group (median 0.74, IQR 0.57-0.85 vs median 0.88, IQR 0.71-0.96; P=.009). Further analysis revealed no significant differences in other rest-activity rhythm metrics between the two groups. Among the patients who had a stroke, a negative correlation was observed between the 4 A's Test scores and relative amplitude (ρ=-0.41; P=.045). Across all participants, positive correlations emerged between the Barthel Index scores and both interdaily stability (ρ=0.34; P=.02) and the most active 10-hour value (ρ=0.42; P=.002).

CONCLUSIONS

This study highlights the relevance of circadian rhythm disruptions in poststroke rehabilitation and provides insights into potential diagnostic and prognostic implications for rest-activity rhythm indicators as digital biomarkers.

The phenotype of delirium based on a close reading of diagnostic criteria

OBJECTIVE

Although delirium is well known to acute care clinicians, the features required for its diagnosis and how to understand and operationalize them remain sticking points in the field. To clarify the delirium phenotype, we present a close reading of past and current sets of delirium diagnostic criteria.

METHODS

We first differentiate the delirium syndrome (i.e., features evaluated at bedside) from additional criteria required for diagnosis. Next, we align related features across diagnostic systems and examine them in context to determine intent. Where criteria are ambiguous, we review common delirium instruments to illustrate how they have been interpreted.

RESULTS

An acute disturbance in attention is universally attested across diagnostic systems. A second core feature denotes confusion and has been included across systems as disturbance in awareness, impaired consciousness, and thought disorganization. This feature may be better understood as a disturbance in thought clarity and operationalized in terms of neuropsychological domains thereby clearly linking it to global neurocognitive disturbance. Altered level of activity describes a third core feature, including motor and sleep/wake cycle disturbances. Excluding stupor (wherein mental content cannot be assessed due to reduced arousal) from delirium, as in DSM-5-TR, is appropriate for a psychiatric diagnosis, but the brain injury exclusion in ICD-11 is unjustified.

CONCLUSIONS

The delirium phenotype involves a disturbance in attention, qualitative thought clarity, and quantitative activity level, including in relation to expected sleep/wake cycles. Future diagnostic systems should include a severity threshold and specify that delirium diagnosis refers to a 24-h period.

Wearable devices in palliative care for people 65 years and older: A scoping review

Objective

The objective of this scoping review is to map existing evidence on the use of wearable devices in palliative care for older people.

Methods

The databases searched included MEDLINE (via Ovid), Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Google Scholar, which was included to capture grey literature. Databases were searched in the English language, without date restrictions. Reviewed results included studies and reviews involving patients aged 65 years or older who were active users of non-invasive wearable devices in the context of palliative care, with no limitations on gender or medical condition. The review followed the Joanna Briggs Institute's comprehensive and systematic guidelines for conducting scoping reviews.

Results

Of the 1,520 reports identified through searching the databases, reference lists, and citations, six reports met our inclusion criteria. The types of wearable devices discussed in these reports were accelerometers and actigraph units. Wearable devices were found to be useful in various health conditions, as the patient monitoring data enabled treatment adjustments. The results are mapped in tables as well as a Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) chart.

Conclusions

The findings indicate limited and sparse evidence for the population group of patients aged 65 years and older in the palliative context. Hence, more research on this particular age group is needed. The available evidence shows the benefits of wearable device use in enabling patient-centred palliative care, treatment adjustments and symptom management, and reducing the need for patients to travel to clinics while maintaining communication with healthcare professionals.

New Delirium Severity Indicators: Generation and Internal Validation in the Better Assessment of Illness (BASIL) Study

BACKGROUND

Delirium is a common and preventable geriatric syndrome. Moving beyond the binary classification of delirium present/absent, delirium severity represents a potentially important outcome for evaluating preventive and treatment interventions and tracking the course of patients. Although several delirium severity assessment tools currently exist, most have been developed in the absence of advanced measurement methodology and have not been evaluated with rigorous validation studies.

OBJECTIVE

We aimed to report our development of new delirium severity items and the results of item reduction and selection activities guided by psychometric analysis of data derived from a field study.

METHODS

Building on our literature review of delirium instruments and expert panel process to identify domains of delirium severity, we adapted items from existing delirium severity instruments and generated new items. We then fielded these items among a sample of 352 older hospitalized patients.

RESULTS

We used an expert panel process and psychometric data analysis techniques to narrow a set of 303 potential items to 17 items for use in a new delirium severity instrument. The 17-item set demonstrated good internal validity and favorable psychometric characteristics relative to comparator instruments, including the Confusion Assessment Method - Severity (CAM-S) score, the Delirium Rating Scale Revised 98, and the Memorial Delirium Assessment Scale.

CONCLUSION

We more fully conceptualized delirium severity and identified characteristics of an ideal delirium severity instrument. These characteristics include an instrument that is relatively quick to administer, is easy to use by raters with minimal training, and provides a severity rating with good content validity, high internal consistency reliability, and broad domain coverage across delirium symptoms. We anticipate these characteristics to be represented in the subsequent development of our final delirium severity instrument.

Role of Wearable Accelerometer Devices in Delirium Studies: A Systematic Review

We sought to determine the feasibility of using wearable accelerometer devices for determining delirium effects on patients' physical activity patterns and detecting delirium and delirium subtype.

DATA SOURCES

PubMed, Embase, and Web of Science.

STUDY SELECTION

Screening was performed using predefined search terms to identify original research studies using accelerometer devices for studying physical activity in relation to delirium.

DATA EXTRACTION

Key data were extracted from the selected articles.

DATA SYNTHESIS

Among the 14 studies identified, there were a total of 315 patients who wore accelerometer devices to record movements related to delirium. Eight studies (57.1%) used accelerometer devices to compare the activity of delirious and nondelirious patients. Delirious patients had lower activity levels, lower restlessness index, higher number of daytime immobility minutes, lower mean activity levels during the day, and higher mean activity levels at night. Delirious patients also had lower actual sleep time, lower sleep efficiency, fewer nighttime minutes resting, fewer minutes resting over 24 hours, and smaller change in activity from day to night. Six studies (42.9%) evaluated the feasibility of using accelerometer devices for detection of delirium and its subtype. Variables including number of postural changes during daytime, frequency of ultrashort, short, and continuous movements were significantly different among the nondelirium and the three delirium subtypes.

CONCLUSIONS

The results from the studies using accelerometer devices in studying delirium demonstrate that accelerometer devices can potentially detect the differences between delirious and nondelirious patients, detect delirium, and determine delirium subtype. We suggest the following directions as the next steps for future studies using accelerometer devices for predicting delirium: benchmark studies with longer data collection, larger and more diverse population size, incorporating related factors (e.g., medications), and evaluating delirium subtype and severity.

A Scoping Review to Map Empirical Evidence Regarding Key Domains and Questions in the Clinical Pathway of Delirium in Palliative Care

CONTEXT

Based on the clinical care pathway of delirium in palliative care (PC), a published analytic framework (AF) formulated research questions in key domains and recommended a scoping review to identify evidence gaps.

OBJECTIVES

To produce a literature map for key domains of the published AF: screening, prognosis and diagnosis, management, and the health-related outcomes.

METHODS

A standard scoping review framework was used by an interdisciplinary study team of nurse- and physician-delirium researchers, an information specialist, and review methodologists to conduct the review. Knowledge user engagement provided context in refining 19 AF questions. A peer-reviewed search strategy identified citations in Medline, PsycINFO, Embase, and CINAHL databases between 1980 and 2018. Two reviewers independently screened records for inclusion using explicit study eligibility criteria for the population, design, delirium diagnosis, and investigational intent.

RESULTS

Of 104 studies reporting empirical data and meeting eligibility criteria, most were conducted in patients with cancer (73.1%) and in inpatient PC units (52%). The most frequent study design was a one or more group, nonrandomized trial or cohort (67.3%). Evidence gaps were identified: delirium risk prediction; comparative effectiveness and harms of prevention, variability in delirium management across PC settings, advanced directive and substitute decision-maker input, and transition of care location; and estimating delirium reversibility. Future rigorous primary studies are required to address these gaps and preliminary concerns regarding the quality of extant literature.

CONCLUSION

Substantial evidence gaps exist, providing opportunities for future research regarding the assessment, prognosis, and management of delirium in PC settings.

Delirium clinical motor subtypes: a narrative review of the literature and insights from neurobiology

INTRODUCTION

Clinical motor subtypes have been long recognised in delirium and, despite a growing body of research, a lack of clarity exists regarding the importance of these motor subtypes. The aims of this review are to (1) examine how the concept of motor subtypes has evolved, (2) explore their relationship to the clinical context, (3) discuss the relationship between the phenomenology of delirium and motor activity, (4) discuss the application of neurobiology to the theory of delirium motor subtypes, and (5) identify methodological issues and provide solutions for further studies.

METHODS

The following databases were searched: PubMed, PsychInfo, EBSCO, Medline, BioMed central and Science Direct. Inclusion criteria specified peer-reviewed research assessing delirium motor subtypes published between 1990 and 2016.

RESULTS

Sixty-one studies met the inclusion criteria. The majority of studies (n = 50) were found to use validated psychometric tools, while the remainder (n = 11) used clinical criteria. The majority of studies (n = 45) were conducted in the medical setting, while the remainder were in the ICU/post-operative setting (n = 17).

CONCLUSION

Although host sensitivities (e.g. frailty) and exogenous factors (e.g. medication exposure) may determine the type of motor disturbance, it remains unclear to what extent motor subtypes are influenced by other features of delirium. The use of more specialised tools (e.g. delirium motor subtyping scale), may enable researchers to develop an approach to delirium that has a greater nosological consistency. Future studies investigating delirium motor subtypes may benefit from enhanced theoretical considerations of the dysfunctional neural substrate of the delirious state.

Comparison of diagnostic classification systems for delirium with new research criteria that incorporate the three core domains

OBJECTIVE

Diagnostic classification systems do not incorporate phenomenological research findings about the three core symptom domains of delirium (Attentional/Cognitive, Circadian, Higher Level Thinking). We evaluated classification performances of novel Trzepacz, Meagher, and Franco research diagnostic criteria (TMF) that incorporate those domains and ICD-10, DSM-III-R, DSM-IV, and DSM-5.

METHODS

Primary data analysis of 641 patients with mixed neuropsychiatric profiles. Delirium (n=429) and nondelirium (n=212) reference standard groups were identified using cluster analysis of symptoms assessed using the Delirium Rating Scale-Revised-98. Accuracy, sensitivity, specificity, positive and negative predictive values (PPV, NPV), and likelihood ratios (LR+, LR-) are reported.

RESULTS

TMF criteria had high sensitivity and specificity (87.4% and 89.2%), more balanced than DSM-III-R (100% and 31.6%), DSM-IV (97.7% and 74.1%), DSM-5 (97.7% and 72.6%), and ICD-10 (66.2% and 100%). PPV of DSM-III-R, DSM-IV, and DSM-5 were <90.0%, while PPV for ICD-10 and TMF were >90%. ICD-10 had the lowest NPV (59.4%). TMF had the highest LR+ (8.06) and DSM-III-R the lowest LR- (0.0). Overall, values for DSM-IV and DSM-5 were similar, whereas for ICD-10 and DSM-III-R were inverse of each other. In the pre-existing cognitive impairment/dementia subsample (n=128), TMF retained its highest LR+ though specificity (58.3%) became less well balanced with sensitivity (87.9%), which still exceeded that of DSM.

CONCLUSIONS

TMF research diagnostic criteria performed well, with more balanced sensitivity and specificity and the highest likelihood ratio for delirium identification. Reflecting the three core domains of delirium, TMF criteria may have advantages in biological research where delineation of this syndrome is important.

Delirium detection based on monitoring of blinks and eye movements

OBJECTIVE

To investigate whether delirious patients differ from nondelirious patients with regard to blinks and eye movements to explore opportunities for delirium detection.

METHODS

Using a single-center, observational study in a tertiary hospital in the Netherlands, we studied 28 delirious elderly and 28 age- and gender-matched (group level) nondelirious elderly, postoperative cardiac surgery patients. Patients were evaluated for delirium by a geriatrician, psychiatrist, or neurologist using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria. Blinks were automatically extracted from electro-oculograms and eye movements from electroencephalography recordings using independent component analysis. The number and duration of eye movements and blinks were compared between patients with and without delirium, based on the classification of the delirium experts described above.

RESULTS

During eyes-open registrations, delirious patients showed, compared with nondelirious patients, a significant decrease in the number of blinks per minute (median: 12 [interquartile range {IQR}: 5-18] versus 18 [IQR: 8-25], respectively; p = 0.02) and number of vertical eye movements per minute (median: 1 [IQR: 0-13] versus 15 [IQR: 2-54], respectively; p = 0.01) as well as an increase in the average duration of blinks (median: 0.5 [IQR: 0.36-0.95] seconds versus 0.34 [IQR: 0.23-0.53] seconds, respectively; p <0.01). During eyes-closed registrations, the average duration of horizontal eye movements was significantly increased in delirious patients compared with patients without delirium (median: 0.41 [IQR: 0.15-0.75] seconds versus 0.08 [IQR: 0.06-0.22] seconds, respectively; p <0.01).

CONCLUSION

Spontaneous eye movements and particularly blinks appear to be affected in delirious patients, which holds promise for delirium detection.

Delirium in adult patients receiving palliative care: a systematic review of the literature

Delirium in palliative care patients is common and its diagnosis and treatment is a major challenge. Our objective was to perform a literature analysis in two phases on the recent scientific evidence (2007-2012) on the diagnosis and treatment of delirium in adults receiving palliative care. In phase 1 (descriptive studies and narrative reviews) 133 relevant articles were identified: 73 addressed the issue of delirium secondarily, and 60 articles as the main topic. However, only 4 prospective observational studies in which delirium was central were identified. Of 135 articles analysed in phase 2 (clinical trials or descriptive studies on treatment of delirium in palliative care patients), only 3 were about prevention or treatment: 2 retrospective studies and one clinical trial on multicomponent prevention in cancer patients. Much of the recent literature is related to reviews on studies conducted more than a decade ago and on patients different to those receiving palliative care. In conclusion, recent scientific evidence on delirium in palliative care is limited and suboptimal. Prospective studies are urgently needed that focus specifically on this highly vulnerable population.

Evidence for the diagnostic criteria of delirium: an update

PURPOSE OF REVIEW

Since the publication of DSM-III in 1980, the essential criteria for delirium have been reduced progressively through DSM-III-R to DSM-IV. As the field moves toward DSM-V and ICD-11, new data can shed light on the nosological changes that are needed so that diagnostic criteria can reflect empirical data. In this study, we reassess the existing or potential criteria for delirium.

RECENT FINDINGS

Phenomenological studies in recent years have informed the criteria for delirium, including the appropriateness of the term 'consciousness' as a core symptom of the diagnosis, additional symptoms of delirium that are frequent but are not currently part of the diagnostic criteria, subsyndromal delirium, motoric subtypes of delirium (hyperactive, hypoactive), and the association of delirium with dementia.

SUMMARY

Recent studies suggest that motoric subtypes should be included as a subtype for delirium but that subsyndromal delirium, although a useful research construct, should not be included in clinical diagnostic criteria given the frequent fluctuation in symptoms over short periods. In addition, though the core symptoms are probably adequate to make the diagnosis, clinicians must be aware of the frequency of other symptoms, for symptoms such as profound sleep disturbance or psychotic symptoms may dominate the clinical picture.