An Initial miRNA Profile of Persons With Persisting Neurobehavioral Impairments and States of Disordered Consciousness After Severe Traumatic Brain Injury.

OBJECTIVE: To examine the merits of using microRNAs (miRNAs) as biomarkers of disorders of consciousness (DoC) due to traumatic brain injury (TBI). SETTINGS: Acute and subacute beds. PARTICIPANTS: Patients remaining in vegetative and minimally conscious states (VS, MCS), an average of 1.5 years after TBI, and enrolled in a randomized clinical trial ( n = 6). Persons without a diagnosed central nervous system disorder, neurotypical controls ( n = 5). DESIGN: Comparison of whole blood miRNA profiles between patients and age/gender-matched controls. For patients, correlational analyses between miRNA profiles and measures of neurobehavioral function. MAIN MEASURES: Baseline measures of whole blood miRNAs isolated from the cellular and fluid components of blood and measured using miRNA-seq and real-time polymerase chain reaction (RT-PCR). Baseline neurobehavioral measures derived from 7 tests. RESULTS: For patients, relative to controls, 48 miRNA were significantly ( P < .05)/differentially expressed. Cluster analysis showed that neurotypical controls were most similar to each other and with 2 patients (VS: n = 1; and MCS: n = 1). Three patients, all in MCS, clustered separately. The only female in the sample, also in MCS, formed an independent group. For the 48 miRNAs, the enriched pathways identified are implicated in secondary brain damage and 26 miRNAs were significantly ( P < .05) correlated with measures of neurobehavioral function. CONCLUSIONS: Patients remaining in states of DoC an average of 1.5 years after TBI showed a different and reproducible pattern of miRNA expression relative to age/gender-matched neurotypical controls. The phenotypes, defined by miRNA profiles relative to persisting neurobehavioral impairments, provide the basis for future research to determine the miRNA profiles differentiating states of DoC and the basis for future research using miRNA to detect treatment effects, predict treatment responsiveness, and developing targeted interventions. If future research confirms and advances reported findings, then miRNA profiles will provide the foundation for patient-centric DoC neurorehabilitation.

"Fluctuation is the norm": Rehabilitation practitioner perspectives on ambiguity and uncertainty in their work with persons in disordered states of consciousness after traumatic brain injury.

The purpose of this study is to describe the clinical lifeworld of rehabilitation practitioners who work with patients in disordered states of consciousness (DoC) after severe traumatic brain injury (TBI). We interviewed 21 practitioners using narrative interviewing methods from two specialty health systems that admit patients in DoC to inpatient rehabilitation. The overarching theme arising from the interview data is "Experiencing ambiguity and uncertainty in clinical reasoning about consciousness" when treating persons in DoC. We describe practitioners' practices of looking for consistency, making sense of ambiguous and hard to explain patient responses, and using trial and error or "tinkering" to care for patients. Due to scientific uncertainty about diagnosis and prognosis in DoC and ambiguity about interpretation of patient responses, working in the field of DoC disrupts the canonical meaning-making processes that practitioners have been trained in. Studying the lifeworld of rehabilitation practitioners through their story-making and story-telling uncovers taken-for-granted assumptions and normative structures that may exist in rehabilitation medical and scientific culture, including practitioner training. We are interested in understanding these canonical breaches in order to make visible how practitioners make meaning while treating patients.

Safety Considerations for the Use of Transcranial Magnetic Stimulation as Treatment for Coma Recovery in People With Severe Traumatic Brain Injury.

OBJECTIVE: For persons in states of disordered consciousness (DoC) after severe traumatic brain injury (sTBI), we report cumulative findings from safety examinations, including serious adverse events (AEs) of a repetitive transcranial magnetic stimulation (rTMS) parameter protocol in 2 different studies. PARTICIPANTS: Seven persons in states of DoC after sTBI with widespread neuropathology, but no large lesions in proximity to the site of rTMS. One participant had a ventriculoperitoneal shunt with programmable valve. METHODS: Two clinical trials each providing 30 rTMS sessions to the right or left dorsolateral prefrontal cortex, involving 300 to 600 pulses over 1 or 2 sessions daily. One study provided concomitant amantadine. Safety indicators monitored related to sleep, temperature, blood pressure, skin integrity, sweating, weight loss, infections, and seizure. RESULTS: Average changes for monitored indicators were of mild severity, with 75 nonserious AEs and 1 serious AE (seizure). The participant incurring a seizure resumed rTMS while taking antieplieptics without further seizure activity. CONCLUSIONS: Considering elevated risks for this patient population and conservative patient selection, findings indicate a relatively safe profile for the specified rTMS protocols; however, potential for seizure induction must be monitored. Future research for this population can be broadened to include patients previously excluded on the basis of profiles raising safety concerns.

A Pilot Trial Examining the Merits of Combining Amantadine and Repetitive Transcranial Magnetic Stimulation as an Intervention for Persons With Disordered Consciousness After TBI.

OBJECTIVE: Report pilot findings of neurobehavioral gains and network changes observed in persons with disordered consciousness (DoC) who received repetitive transcranial magnetic stimulation (rTMS) or amantadine (AMA), and then rTMS+AMA. PARTICIPANTS: Four persons with DoC 1 to 15 years after traumatic brain injury (TBI). DESIGN: Alternate treatment-order, within-subject, baseline-controlled trial. MAIN MEASURES: For group and individual neurobehavioral analyses, predetermined thresholds, based on mixed linear-effects models and conditional minimally detectable change, were used to define meaningful neurobehavioral change for the Disorders of Consciousness Scale-25 (DOCS) total and Auditory-Language measures. Resting-state functional connectivity (rsFC) of the default mode and 6 other networks was examined. RESULTS: Meaningful gains in DOCS total measures were observed for 75% of treatment segments and auditory-language gains were observed after rTMS, which doubled when rTMS preceded rTMS+AMA. Neurobehavioral changes were reflected in rsFC for language, salience, and sensorimotor networks. Between networks interactions were modulated, globally, after all treatments. CONCLUSIONS: For persons with DoC 1 to 15 years after TBI, meaningful neurobehavioral gains were observed after provision of rTMS, AMA, and rTMS+AMA. Sequencing and combining of treatments to modulate broad-scale neural activity, via differing mechanisms, merits investigation in a future study powered to determine efficacy of this approach to enabling neurobehavioral recovery.