Research considerations for prospective studies of patients with coma and disorders of consciousness

Disorders of consciousness are neurological conditions characterized by impaired arousal and awareness of self and environment. Behavioural responses are absent or are present but fluctuate. Disorders of consciousness are commonly encountered as a consequence of both acute and chronic brain injuries, yet reliable epidemiological estimates would require inclusive, operational definitions of the concept, as well as wider knowledge dissemination among involved professionals. Whereas several manifestations have been described, including coma, vegetative state/unresponsive wakefulness syndrome and minimally conscious state, a comprehensive neurobiological definition for disorders of consciousness is still lacking. The scientific literature is primarily observational, and studies-specific aetiologies lead to disorders of consciousness. Despite advances in these disease-related forms, there remains uncertainty about whether disorders of consciousness are a disease-agnostic unitary entity with a common mechanism, prognosis or treatment response paradigm. Our knowledge of disorders of consciousness has also been hampered by heterogeneity of study designs, variables, and outcomes, leading to results that are not comparable for evidence synthesis. The different backgrounds of professionals caring for patients with disorders of consciousness and the different goals at different stages of care could partly explain this variability. The Prospective Studies working group of the Neurocritical Care Society Curing Coma Campaign was established to create a platform for observational studies and future clinical trials on disorders of consciousness and coma across the continuum of care. In this narrative review, the author panel presents limitations of prior observational clinical research and outlines practical considerations for future investigations. A narrative review format was selected to ensure that the full breadth of study design considerations could be addressed and to facilitate a future consensus-based statement (e.g. via a modified Delphi) and series of recommendations. The panel convened weekly online meetings from October 2021 to December 2022. Research considerations addressed the nosographic status of disorders of consciousness, case ascertainment and verification, selection of dependent variables, choice of covariates and measurement and analysis of outcomes and covariates, aiming to promote more homogeneous designs and practices in future observational studies. The goal of this review is to inform a broad community of professionals with different backgrounds and clinical interests to address the methodological challenges imposed by the transition of care from acute to chronic stages and to streamline data gathering for patients with disorders of consciousness. A coordinated effort will be a key to allow reliable observational data synthesis and epidemiological estimates and ultimately inform condition-modifying clinical trials.

Caregivers of people with disorders of consciousness: which burden predictors?

OBJECTIVES

Caregivers of patients diagnosed with disorders of consciousness (DoCs) play a pivotal role in the care pathway of these patients. Due to the high costs of care, among other symptoms and disorders previously described in the literature, they can manifest also mood and stress-related disorders which greatly impact their life and increase their burden. It is noteworthy to identify which factors are better related to the manifestation of mood and stress-related disorders to care for the caregivers in time. However, no studies have explored which factors are related to the manifestation of these disorders within this population yet.

MATERIALS AND METHODS

We explored with different questionnaires whether patient-, caregiver-, and caregiving environment-related factors are associated with mood and stress-related disorders on 114 caregivers of patients with DoCs.

RESULTS

Our results showed that female caregivers manifested higher levels of both depression and prolonged grief disorder; furthermore, the presence of economic problems increased the levels of depression. Moreover, different levels of caregivers' depression, anxiety, anger expression, and prolonged grief disorder were closely linked to the degree of behavioural responsiveness of the patients.

CONCLUSIONS

Our results highlighted the need to consider also caregivers' mood and stress-related disorders when defining the care pathway of patients with DoCs; indeed, caregivers constitute the main environment of DoC patients and they need tailored interventions aimed at reducing their burden due to caregiving.

[The Russian version of Coma Recovery Scale-revised - a standardized method for assessment of patients with disorders of consciousness]

The authors officially present for the first time the Russian version of Coma Recovery Scale-Revised (CRS-R). Today CRS-R is the only validated scale in Russian for assessment of patients with chronic disorders of consciousness (DOC). The study showed high consistency for different researchers, high sensitivity in the evaluation of patients over time as well as high concurrent validity. This article contains the text of the scale and recommendations how to use CRS-R and interpret the data. Presented version of the CRS-R is recommended for use in DOC patients. Russian version of the CRS-R is a standardized, comprehensive and systematic approach to the examination and assessment of patients with chronic DOS. It ensures the standard approach to examination and assessment that warrants the accuracy and homogeneity of the obtained results.