Disorders of Consciousness, Minimally Conscious State, Vegetative State
Conditions
Keywords
vegetative state, minimally conscious state, disorders of consciousness, transcranial direct current stimulation
Brief summary
Previous studies showed that anodal transcranial direct current stimulation (tDCS) applied to the left dorsolateral prefrontal (DLPF) cortex transiently improves performance of memory and attention. Investigator assessed the effects of left DLPF-tDCS on Coma Recovery Scale-Revised (CRS-R) scores in severely brain damaged patients with disorders of consciousness in a double-blind sham-controlled experimental design.
Detailed description
Following severe brain damage and coma, some patients may remain in a vegetative state (VS) or minimally conscious state (MCS). At present, there are no evidence-based guidelines regarding the treatment of patients with disorders of consciousness (DOC). Investigator aim to assess the effect of single session anodal (i.e., excitatory) transcranial direct current stimulation (tDCS) of the left dorsolateral prefrontal cortex (DLPF) on the level of consciousness in DOC patients in a double blind randomized sham controlled study. tDCS is a form of safe non-invasive cortical stimulation, modulating cortical excitability at stimulation sites via weak polarizing currents, previously reported to transiently improve working memory and attention by stimulating the left DLPF in healthy subjects and patients with stroke, Parkinson's or Alzheimer's disease.
Interventions
DEVICEAnodal tDCS
patients received anodal tDCS (on PFDL cortex) during 20 minutes preceded and followed by a behavioral assessment (Coma Recovery Scale Revised)
DEVICEsham tDCS
Patient received a sham tDCS (5sec of stimulation). The device runs during 20minutes and the anode was placed over the DLPF cortex. A behavioral assessment preceded and followed the stimulation.
Sponsors
University of Liege
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)
Eligibility
Sex/Gender
ALL
Age
15 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
* post-comatose patients * patients in vegetative/unresponsive or minimally conscious state * patients with stable cardiorespiratory parameters * patients free of sedative drugs and Na+ or Ca++ channel blockers (e.g., carbamazepine) or NMDA receptor antagonists (e.g., dextromethorphan)
Exclusion criteria
* premorbit neurology antecedent * patients in coma or \<1week after the acute brain insult * patients with a metallic cerebral implant or a pacemaker (in line with the safety criteria for tDCS in humans)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in CRS-R Total Scores | Baseline and directly after the tDCS (20 minutes) | At the group level, assess the modification of CRS-R total scores in anodal tDCS as compared to sham stimulation in VS/UWS and MCS populations The Coma Recovery Scale Revised (CRS-R) is a behavioral scale performed at the patient's bedside. It consists of 23 hierarchically arranged items that comprise 6 subscales addressing auditory, visual, motor, verbal, communication, and arousal functions. Scoring is based on the presence or absence of specific behavioral responses to sensory stimuli administered in a standardized manner. Maximum scores of each subscale are summed to obtain the total score (from 0 to 23). The lowest item on each subscale represents reflexive activity, whereas the highest items represent cognitively mediated behaviors. |
Secondary
| Measure | Time frame |
|---|---|
| Influence of Diagnosis on the Results | participants will be followed for the duration of 1 year |
| Influence of Etiology on the Results | participants will be followed for the duration of 1 year |
| Influence of Time Since Insult on the Results | participants will be followed for the duration of 1 year |
Countries
Belgium
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Anodal tDCS First Patients received anodal tDCS during 20 minutes. Then, washout of 2days. Then sham tDCS. | 32 |
| Sham tDCS First Patients received sham tDCS during 20 minutes. Then, washout of 2days. Then andoal tDCS. | 23 |
| Total | 55 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | change of diagnosis | 4 | 3 |
Baseline characteristics
| Characteristic | Anodal tDCS First | Sham tDCS First | Total |
|---|---|---|---|
| Age, Customized | 46 years STANDARD_DEVIATION 17 | 40 years STANDARD_DEVIATION 19 | 43 years STANDARD_DEVIATION 18 |
| Region of Enrollment Belgium | 32 participants | 23 participants | 55 participants |
| Sex: Female, Male Female | 9 Participants | 7 Participants | 16 Participants |
| Sex: Female, Male Male | 23 Participants | 16 Participants | 39 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 55 | 0 / 55 |
| serious Total, serious adverse events | 0 / 55 | 0 / 55 |
Outcome results
Primary
Change in CRS-R Total Scores
At the group level, assess the modification of CRS-R total scores in anodal tDCS as compared to sham stimulation in VS/UWS and MCS populations The Coma Recovery Scale Revised (CRS-R) is a behavioral scale performed at the patient's bedside. It consists of 23 hierarchically arranged items that comprise 6 subscales addressing auditory, visual, motor, verbal, communication, and arousal functions. Scoring is based on the presence or absence of specific behavioral responses to sensory stimuli administered in a standardized manner. Maximum scores of each subscale are summed to obtain the total score (from 0 to 23). The lowest item on each subscale represents reflexive activity, whereas the highest items represent cognitively mediated behaviors.
Time frame: Baseline and directly after the tDCS (20 minutes)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Anodal tDCS First | Change in CRS-R Total Scores | 12.17 units on a scale | Standard Deviation 4.32 |
| Sham tDCS First | Change in CRS-R Total Scores | 10.60 units on a scale | Standard Deviation 4.19 |
Secondary
Influence of Diagnosis on the Results
Time frame: participants will be followed for the duration of 1 year
Secondary
Influence of Etiology on the Results
Time frame: participants will be followed for the duration of 1 year
Secondary
Influence of Time Since Insult on the Results
Time frame: participants will be followed for the duration of 1 year