The neuropsychological course of acute delirium in adult hematopoietic stem cell transplantation patients

The neuropsychological profile of delirium vulnerability: A systematic review and meta-analysis

Delirium is a common neurocognitive disorder in hospitalised older adults with substantial negative consequences. Impaired global cognition is a well-established delirium risk factor. However, poor performance on attention tests and higher intra-subject variability may be more sensitive delirium risk factors, given the disorder is characterised by a fluctuating course and attentional deficits. We systematically searched databases (Embase, PsycINFO, MEDLINE) and 44 studies satisfied inclusion criteria. Random-effects meta-analysis models showed poor performance in all cognitive domains except perception was significantly associated with incident delirium. Largest effects were for orientation (g=-1.20) and construction and motor performance (g=-0.60). These effects were no longer significant in the subgroup without pre-existing cognitive impairment, where executive functions and verbal functions and language skills were associated with incident delirium. A small, non-significant association between intra-subject variability and incident delirium was found (g=0.42). Cognitive domain specific tests may be quicker and more sensitive predictors of incident delirium. This pattern of neuropsychological findings supports the proposition that vulnerability for delirium manifests as a dysfunction of whole-brain information integration.

Delirium in Children Undergoing Hematopoietic Cell Transplantation: A Multi-Institutional Point Prevalence Study

Introduction: Delirium occurs frequently in adults undergoing hematopoietic cell transplantation, with significant associated morbidity. Little is known about the burden of delirium in children in the peri-transplant period. This study was designed to determine delirium rates, define risk factors (demographic and treatment related), and establish feasibility of multi-institutional bedside screening for delirium in children undergoing hematopoietic cell transplant. Methods: This is a multi-institutional point prevalence study. All subjects were prospectively screened for delirium twice daily using the Cornell Assessment of Pediatric Delirium over a 10-day period. De-identified data, including basic demographics and daily characteristics, were extracted from the electronic medical record. Results: Eleven North American institutions were included, 106 children were enrolled, and 883 hospital days were captured. Delirium screening was successfully completed on more than 98% of the study days. Forty-eight children (45%) developed delirium over the course of the 10-day study. Children were diagnosed with delirium on 161/883 study days, for an overall delirium rate of 18% per day. Higher delirium rates were noted in children <5 years old (aOR 0.41 for children over 5 years), and in association with specific medications (melatonin, steroids, and tacrolimus). Conclusion: Delirium was a frequent occurrence in our study cohort, with identifiable risk factors. Delirium screening is highly feasible in the pediatric hematopoietic cell transplant patient population. A large-scale prospective longitudinal study following children throughout their transplant course is urgently needed to fully describe the epidemiology of pediatric delirium, explore the effects of delirium on patient outcomes, and establish guidelines to prevent and treat delirium in the peri-transplant period.

Clinical and Neuroimaging Correlates of Post-Transplant Delirium

Delirium is common among adults undergoing hematopoietic stem cell transplantation (HCT), although the clinical and neuroimaging correlates of post-HCT delirium have not been adequately delineated. We therefore examined the frequency of delirium and neuroimaging correlates of post-transplant delirium in a retrospective cohort of 115 adults undergoing neuroimaging after allogeneic HCT. Delirium was established using previously validated methods for retrospective identification of chart-assessed postprocedural delirium. Chart reviews were independently conducted by a multidisciplinary team with expertise in HCT, psychiatry, and psychology on consecutive allogeneic HCT patients who underwent neuroimaging assessments and transplantation at a single center between January 2009 and December 2016. Neuroimaging markers of white matter damage and brain volume loss were also recorded. In total, 115 patients were included, ranging in age from 20 to 74 years (mean [SD] age, 49 [13]). Fifty-three patients (46%) developed post-HCT delirium. In an adjusted model, delirium incidence was associated with older age (odds ratio [OR], 1.92 [1.28, 2.87] per decade, P = .002), greater severity of white matter hyperintensities (OR, 1.95 [1.06, 3.57], P = .031), and conditioning intensity (OR, 6.37 [2.20, 18.45], P < .001) but was unrelated to cortical atrophy (P = .777). Delirium was associated with fewer hospital-free days (P = .023) but was not associated with overall survival (hazard ratio, 0.95 [0.56, 1.61], P = .844). Greater incidence of delirium following HCT was associated with greater age, microvascular burden, and conditioning intensity. Pre-HCT consideration of microvascular burden and other neuroimaging biomarkers of risk may be warranted.

Cognitive and Social Cognitive Self-assessment in Autistic Adults

An aspect of metacognition associated with broader functional abilities in several clinical conditions, but previously unexamined in autism, is self-assessment (i.e., the ability to accurately self-evaluate one's own performance). We compared self-assessment between 37 autistic adults without intellectual disability to 39 non-autistic (NA) controls on a series of three general cognitive and three social cognitive tasks. Whereas autistic adults and NA adults did not differ in their self-assessment accuracy on general cognitive tasks, they did on social cognitive tasks, with autistic adults demonstrating lower accuracy. The direction of their inaccuracy was variable (i.e., both over and underestimation), and self-assessment was largely unrelated to their level of social functioning. Over versus underestimation may have different functional implications, and warrants future investigation.

Neurologic complications after allogeneic transplantation: a meta-analysis

Objective

Neurologic adverse events remain challenging complications with poor morbidity and mortality post adult allogeneic hematopoietic cell transplantation (allo‐HCT) for hematologic diseases. We conducted a systematic review and meta‐analysis to determine their spectrum, incidence, and impact on survival.

Methods

We searched MEDLINE, COCHRANE, EMBASE through March 2019 for all types of primary studies. Two independent reviewers screened, extracted data, and assessed risk of bias (RoB).

Results

We identified 552 eligible studies describing 57.972 patients; one randomized controlled trial, two case–control, 17 prospective, 86 retrospective cohort studies, 21 case series, and 425 case reports. RoB ranged from fair to high although case series were low‐risk. The majority of studies traced infectious or drug‐related neurologic manifestations. Infectious complications were present in 2.7% (95% CI 1.9–3.6) and 3.3% (95% CI 0.8–7.1) of patients in retrospective and prospective cohort studies, respectively. In retrospective studies, 3.4% (95% CI 2.1–4.9) of patients suffered from drug‐related neurologic events. In prospective cohorts the equivalent incidence was 13% (95% CI 4.2–24.8). Neurologic complications had a detrimental impact on survival.

Interpretation

Our study highlights the wide spectrum and significant impact of neurologic complications on survival post allo‐HCT. This systematic review summarizes existing data and provides the necessary background information for every physician involved in the management of these patients.

Delirium in Hospitalized Children with Cancer: Incidence and Associated Risk Factors

OBJECTIVE

To assess the incidence of delirium and its risk factors in hospitalized children with cancer.

STUDY DESIGN

In this cohort study, all consecutive admissions to a pediatric cancer service over a 3-month period were prospectively screened for delirium twice daily throughout their hospitalization. Demographic and treatment-related data were collected from the medical record after discharge.

RESULTS

A total of 319 consecutive admissions, including 186 patients and 2731 hospital days, were included. Delirium was diagnosed in 35 patients, for an incidence of 18.8%. Risk factors independently associated with the development of delirium included age <5 years (OR = 2.6, P = .026), brain tumor (OR = 4.7, P = .026); postoperative status (OR = 3.3, P = .014), and receipt of benzodiazepines (OR = 3.7,P < .001). Delirium was associated with increased hospital length of stay, with median length of stay for delirious patients of 10 days compared with 5 days for patients who were not delirious during their hospitalization (P < .001).

CONCLUSIONS

In this cohort, delirium was a frequent complication during admissions for childhood cancer, and was associated with increased hospital length of stay. Multi-institutional prospective studies are warranted to further characterize delirium in this high-risk population and identify modifiable risk factors to improve the care provided to hospitalized children with cancer.

Objective assessment of attention in delirium: a narrative review

OBJECTIVE

Inattention is a core feature of delirium, and valid assessment of attention is central to diagnosis. Methods of measuring attention in delirium can be divided into two broad categories: (i) objective neuropsychological testing; and (ii) subjective grading of behaviour during interview and clinical examination. Here, we review and critically evaluate studies of objective neuropsychological testing of attention in delirium. We examine the implications of these studies for delirium detection and monitoring in clinical practice and research, and how these studies inform understanding of the nature of attentional deficits in delirium.

METHODS

Searches of MEDLINE and ISI Web of Knowledge databases were performed to identify studies in which objective tests of attention had been administered to patients with delirium, who had been diagnosed using DSM or ICD criteria.

RESULTS

Sixteen publications were identified. The attention tests administered in these studies were grouped into the following categories: measures of attention span, vigilance tests, other pen-and-paper tests (e.g. Trail Making Test) and computerised tests of speeded reaction, vigilance and sustained attention. Patients with delirium showed deficits on all tasks, although most tasks were not considered pure measures of attention. Five papers provided data on differential diagnosis from dementia. Cancellation tests, spatial span tests and computerised tests of sustained attention discriminated delirium from dementia. Five studies presented reliability or validity statistics.

CONCLUSIONS

The existing evidence base on objective assessment of attention in delirium is small. Objective testing of attention is underdeveloped but shows considerable promise in clinical practice and research.

Incidence and Cause of Delirium in Hospitalized Patients between the Ages of 18 and 56: A Retrospective Chart Review

Background. Delirium is a common and devastating condition which has been well characterized in elderly cancer patients, but little is known about delirium in cancer patients under the age of 65. Aim. A pilot study to explore the incidence and potential causes of delirium in hospitalized advanced cancer patients at the age of 18–56 years. Design. A retrospective chart review using validated instruments was used to examine the charts of hematology-oncology admissions in a large academic institution. Data was collected as to the likelihood of delirium and potential precipitants. Results. Delirium incidence was 29% among advanced cancer patients. The associated precipitants of delirium were multifactorial, the most common being medications and infection. Delirium was more common in patients admitted for either acute symptom management or the presence of a lung malignancy. Patients with delirium demonstrated significantly increased total hospital cost and a borderline significant result for increased mortality compared to those without delirium. Conclusions. Delirium is common in hospitalized advanced cancer patients (age 18–56 years) and the cause is typically multifactorial. Delirium results in a more complicated hospital course and likely increased mortality. Further research is needed to define strategies to prevent and treat this common and distressing condition.

A systematic review and meta-analysis of changes in cognitive functioning in adults undergoing hematopoietic cell transplantation

Evidence is mixed regarding the effects of hematopoietic cell transplantation (HCT) on changes in cognitive functioning among adults. Meta-analysis, which is designed to help reconcile conflicting findings, has not yet been conducted on studies of adults receiving HCT. To fill this gap, the current study provides a systematic review and meta-analysis of cognitive functioning in adults receiving HCT. A search of PubMed, PsycInfo, CINAHL, and Cochrane Library yielded 732 abstracts, which were independently evaluated by pairs of raters. Seventeen studies were systematically reviewed; eleven were retained for meta-analysis. There was agreement that cognitive impairments are evident for a subset of patients prior to HCT. Meta-analytic findings of 404 patients revealed no significant changes in cognitive functioning pre- to post-HCT (P values > .05). Age, time since transplant, and total body irradiation were not associated with changes in cognitive functioning. Patients who received autologous transplants were more likely to demonstrate improvements in attention (P = .004). The systematic review identified several limitations of existing literature, including small, clinically heterogeneous samples. Large, cooperative group studies are needed to address these design limitations. Nevertheless, results from the current meta-analysis suggest that cognitive functioning does not significantly change following HCT.

Risk factors for delirium in patients undergoing hematopoietic stem cell transplantation

BACKGROUND

Delirium is common after hematopoietic stem cell transplantation (HSCT) and is associated with increased morbidity and mortality. Early recognition and treatment have been shown to improve long-term outcomes. We sought to investigate the relationship between potential risk factors and the development of delirium following HSCT.

METHODS

Fifty-four inpatients admitted for HSCT were assessed prospectively for delirium every 2 to 3 days during their inpatient stay using standardized delirium and neuropsychological measures. Self reports of medical history, medical records, and neurocognitive and psychiatric assessments were used to identify risk factors. Both pre- and post-HSCT risk factors were examined.

RESULTS

Delirium incidence was 35% and occurred with highest frequency in the 2 weeks following transplant. The only pre-transplantation risk factor was lower oxygen saturation (P = .003). Post-transplantation risk factors for delirium included higher creatinine (P < .0001), higher blood urea nitrogen levels (P = .005), lower creatinine clearance (P = .0006), lower oxygen saturation (P = .001), lower hemoglobin (P = .04), and lower albumin (P = .03). There was no observed association with level of cognitive performance, transplant type, disease severity, medical comorbidity index, age, or conditioning regimen.

CONCLUSIONS

Routine laboratory values can assist in the identification of high-risk patients before delirium onset to improve early detection and treatment of delirium after HSCT.