Behavioral scales variability in patients with prolonged disorders of consciousness

Association of Patient Characteristics With Recovery in Adults With Disorders of Consciousness

OBJECTIVE

To describe the characteristics of patients enrolled in disorders of consciousness (DoC) rehabilitation programs and to examine factors associated with improvement beyond measurement error on neurobehavioral function. Outcomes for adults with DoC after severe brain injury are highly variable and difficult to predict. Applying a minimal detectable change (MDC) threshold to change measures can identify help to distinguish true improvement or decline from random fluctuation. We also evaluated whether change in neurobehavioral function during the first 2 weeks of rehabilitation was associated with change between 2 and 4 weeks.

DESIGN

Retrospective cohort study. Data were generated as part of standard clinical care.

SETTING

Postacute inpatient facilities with specialized DoC programs at 2 large, urban health care systems.

PARTICIPANTS

Adults with DoC after severe brain injury (N=696).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Improvement beyond measurement error, calculated as the MDC with a 90% confidence interval (9 units) on the Coma Recovery Scale-Revised (CRS-R), using an equal-interval 0-100 unit transformed total measure. The MDC threshold was applied to change in CRS-R total measure from first to last CRS-R administration (up to 60 elapsed).

RESULTS

Two-thirds of the sample (n=445) improved beyond the MDC on the CRS-R; 23 participants declined beyond measurement error, and 228 participants changed less than the MDC. Patients with less time elapsed between injury and first CRS-R assessment were more likely to improve beyond the MDC. Change during the first 2 weeks of rehabilitation was not associated with change between 2 and 4 weeks.

CONCLUSIONS

Our results underscore the importance of measuring change with greater precision for adults with DoC, as within-state change (or lack thereof) could inform rehabilitation treatment decisions about whether interventions are working as intended.

Vagus nerve stimulation: a physical therapy with promising potential for central nervous system disorders

The diseases of the central nervous system (CNS) often cause irreversible damage to the human body and have a poor prognosis, posing a significant threat to human health. They have brought enormous burdens to society and healthcare systems. However, due to the complexity of their causes and mechanisms, effective treatment methods are still lacking. Vagus nerve stimulation (VNS), as a physical therapy, has been utilized in the treatment of various diseases. VNS has shown promising outcomes in some CNS diseases and has been approved by the Food and Drug Administration (FDA) in the United States for epilepsy and depression. Moreover, it has demonstrated significant potential in the treatment of stroke, consciousness disorders, and Alzheimer's disease. Nevertheless, the exact efficacy of VNS, its beneficiaries, and its mechanisms of action remain unclear. This article discusses the current clinical evidence supporting the efficacy of VNS in CNS diseases, providing updates on the progress, potential, and potential mechanisms of action of VNS in producing effects on CNS diseases.

Meta-analysis of the diagnostic value of functional magnetic resonance imaging for distinguishing unresponsive wakefulness syndrome/vegetative state and minimally conscious state

Objective

Unresponsive wakefulness syndrome/vegetative state (UWS/VS) and minimally conscious state (MCS) are considered different clinical entities, but their differential diagnosis remains challenging. As a potential clinical tool, functional magnetic resonance imaging (fMRI) could detect residual awareness without the need for the patients' actual motor responses. This study aimed to investigate the diagnostic value of fMRI for distinguishing between UWS/VS and MCS through a meta-analysis of the existing studies.

Methods

We conducted a comprehensive search (from the database creation date to November. 2023) for relevant English articles on fMRI for the differential diagnosis of UWS/VS and MCS. The pooled sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), summary receiver operating characteristic (SROC) curve, and area under the curve (AUC) were calculated to assess the diagnostic value of fMRI in distinguishing between UWS/VS and MCS. The statistical I 2 test was used to assess heterogeneity, and the source of heterogeneity was investigated by performing a meta-regression analysis. Publication bias was assessed using the Deeks funnel plot asymmetry test.

Results

Ten studies were included in the meta-analysis. The pooled sensitivity and specificity were 0.71 (95% CI 0.62-0.79) and 0.71 (95% CI 0.54-0.84), respectively. The fMRI for the differential diagnosis of UWS/VS and MCS has a moderate positive likelihood ratio (2.5) and a relatively low negative likelihood ratio (0.40). Additionally, SROC curves showed that the AUC was 0.76 (95% CI 0.72-0.80).

Conclusion

Functional magnetic resonance imaging has a good performance in the differential diagnosis of UWS/VS and MCS, and may provide a potential tool for evaluating the prognosis and guiding the rehabilitation therapy in patients with disorders of consciousness.

Wessex Head Injury Matrix in Patients with Prolonged Disorders of Consciousness: A Reliability Study

Introduction: The Wessex Head Injury Matrix (WHIM) was developed to assess patients with disorders of consciousness (DOC) and was tested in terms of inter-rater reliability (IRR) and test-retest reliability (TRR) in the year 2000. The American Congress of Rehabilitation and Medicine reported that IRR and TRR were unproven. We aim to assess the reliability of the WHIM in prolonged DOC patients (PDOC). Methods: A total of 51 PDOC patients (32 unresponsive wakefulness syndrome (UWS/VS) and 19 minimally conscious state (MCS)) who were hosted in a dedicated unit for long-term brain injury care were enrolled. The time from injury ranged from 182 to 3325 days. Two raters administered the Coma Recovery Scale-Revised (CRS-R) and the WHIM to test the IRR and TRR. The TRR was administered two weeks after the first assessment. Results: For the CRS-R, the agreement in IRR and TRR was perfect between the two raters. The agreement for the WHIM ranged from substantial to almost perfect for IRR and from fair to substantial for the TRR. Conclusions: The WHIM showed a strong IRR when administered by expert raters and strongly correlated with the CRS-R. This study provides further evidence of the psychometric qualities of the WHIM and the importance of its use in PDOC patients.

Stimulation of vagus nerve for patients with disorders of consciousness: a systematic review

Purpose

The purpose of this study is to evaluate the efficacy and safety of stimulating the vagus nerve in patients with disorders of consciousness (DOCs).

Methods

A comprehensive systematic review was conducted, encompassing the search of databases such as PubMed, CENTRAL, EMBASE and PEDro from their inception until July 2023. Additionally, manual searches and exploration of grey literature were performed. The literature review was conducted independently by two reviewers for search strategy, selection of studies, data extraction, and judgment of evidence quality according to the American Academy of Cerebral Palsy and Developmental Medicine (AACPDM) Study Quality Scale.

Results

A total of 1,269 articles were retrieved, and 10 studies met the inclusion criteria. Among these, there were three case reports, five case series, and only two randomized controlled trials (RCTs). Preliminary studies have suggested that stimulation of vagus nerve can enhance the levels of DOCs in both vegetative state/unresponsive wakefulness state (VS/UWS) and minimally conscious state (MCS). However, due to a lack of high-quality RCTs research and evidence-based medical evidence, no definitive conclusion can be drawn regarding the intervention's effectiveness on consciousness level. Additionally, there were no significant adverse effects observed following stimulation of vagus nerve.

Conclusion

A definitive conclusion cannot be drawn from this systematic review as there was a limited number of eligible studies and low-quality evidence. The findings of this systematic review can serve as a roadmap for future research on the use of stimulation of vagus nerve to facilitate recovery from DOCs.