Depression Disorders, Suicidal Ideation Active
Conditions
Keywords
tACS, Suicidal ideation, Rumination, Entrapment, Depression, Non-invasive brain stimulation, Suicidal thoughts and behavior
Brief summary
The goal of this clinical trial is to determine whether modulating default mode network (DMN) alpha connectivity using transcranial alternating current stimulation (tACS) can reduce rumination and, in turn, mitigate feelings of entrapment and suicidal ideation in individuals with active suicidal ideation and depression. The main questions it aims to answer are: 1. Is personalized tACS stimulation of the DMN associated with reduced rumination 24 hours after stimulation? 2. Does a reduction in rumination result in lower feelings of entrapment and suicidal ideation? 3. Does personalized tACS stimulation of the DMN lead to a reduction of DMN alpha connectivity? Researchers will compare active tACS stimulation to sham stimulation to assess whether modulating alpha connectivity has a specific effect on rumination, entrapment, suicidal ideation, and DMN alpha connectivity. Participants will: * Receive either active or sham tACS stimulation during stimulation sessions, but all participants will receive active tACS at least once. * Complete self-report measures of rumination, entrapment, and suicidal ideation before and after stimulation. * Undergo EEG recordings to assess changes in DMN alpha connectivity. This clinical trial will be preceded by a pilot study in healthy participants with an anticipated completion of data collection in August 2025.
Interventions
PROCEDURESham alpha-tACS
A sinusoidal ± 2mA current adjusted to the individual alpha peak frequency with in-phase stimulation at parieto-occipital brain areas and anti-phase stimulation in frontal brain areas. The stimulation will involve a 10s ramp-up, followed by an immediate 10s ramp-down (no stimulation afterwards).
PROCEDUREalpha-tACS
Active tACS with a sinusoidal ± 2mA current adjusted to the individual alpha peak frequency with a 10s ramp-up and 10s ramp-down after stimulation. In-phase stimulation will be applied to parieto-occipital brain areas and anti-phase stimulation will be applied to frontal brain areas
Sponsors
Sebastian Olbrich
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Masking description
Investigators assessing primary electroencephalography (EEG) outcomes will also be blinded to the assigned study arm.
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Active suicidal ideation defined by a score ≥3 on item #10 of the Montgomery-Asberg Depression Rating Scale (MADRS) and a combined score of ≥2 on items #4 + #5 of the Beck Scale for Suicide Ideation (BSS) * Clinical diagnosis of a mild to severe depressive episode without psychotic symptoms * Voluntary patients at inpatient, outpatient, or day-clinic units of mental health care settings in the greater Zurich area * Aged 18-65 years * Fluent in German * Ability to give written informed consent
Exclusion criteria
* Mental disorders due to known physiological conditions * Schizophrenia, schizotypal, delusional, and other non-mood psychotic disorders * Intellectual disabilities * Concurrent vagus nerve stimulation, transcranial magnetic stimulation, electro-convulsive therapy, or treatment with nitrous oxide * Pregnancy or breast-feeding * Chronic migraines * Metal implants or any other factor that - in the investigators' judgment - would unduly affect patient safety or compliance during this study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| EEG alpha functional connectivity (phase synchronization) | Pre-stimulation to post-stimulation at visit 2 (up to 1 hour) | The primary outcome measure will be changes in EEG alpha functional connectivity between pre- and post-stimulation at visit 2 (stimulation visit 1) in the active versus sham group (between-person comparison). EEG alpha functional connectivity will also be assessed at visit 4 (stimulation visit 2). Allowing for between- and within-person comparisons as secondary outcomes. |
| Response style questionnaire (RSQ-10D) | Visit 2 to visit 3 (24 hours) | The primary outcome will be changes in rumination between visit 2 (pre-stimulation) and visit 3 (24 hours post-stimulation) in the active versus sham group (between-person comparison). Rumination will also be assessed at visit 4 and visit 5, allowing for between- and within-person comparisons as secondary outcome measures. The RSQ-10D measures two facets of rumination: brooding and reflection with 5 items each. Scores per facet range from 5 to 20 with higher scores indicating higher rumination. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Clinical Global Impression of Suicidality (CGI-SS-R) | Visits 2-5 (24 hours) | Changes in risk for suicide between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The CGI-SS-R is a single-item clinician rating scale where 1 indicates normal, not at all suicidal and 7 indicates among the most extremely suicidal patients |
| Clinical Global Impression of Imminent Suicide Risk (CGI-SR-I) | Visits 2-5 (24 hours) | Changes in risk for suicide between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The CGI-SR-I is a single-item clinician rating scale where 1 indicates no imminent suicide risk and 7 indicates extreme imminent suicide risk |
| Suicidal Intent Visual Analogue Scale (S-VAS) | Visits 2-5 (24 hours) | Changes in suicidal intent between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The S-VAS is a single-item visual analogue scale. Scores range from 0 to 100 with 0 indicating no urge to kill myself and 100 indicating extreme urge to kill myself |
| Short Defeat and Entrapment Scale (SDES) | Visits 2-5 (24 hours) | Changes in defeat and entrapment between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The SDES is an 8-item scale measuring defeat and entrapment with 4 items each. Scores range from 0 to 16 per facet (i.e., defeat/entrapment) with higher scores indicating higher defeat and entrapment, respectively. |
| Beck Depression Inventory (BDI-II) | Visits 2-5 (24 hours) | Changes in depressive symptoms between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The BDI is a 21-item scale measuring depressive symptoms. Sum scores range from 0 to 63 with higher scores indicating higher severity of depressive symptoms. |
| Montgomery-Asberg Depression Rating Scale (MADRS) | Visits 2-5 (24 hours) | Changes in depressive symptoms between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The MADRS is a10-item clinician rating scale measuring depressive symptoms. Scores range from 0 to 60 with higher scores indicating higher severity of depressive symptoms. |
| Beck Scale for Suicide Ideation (BSS) | Visits 2-5 (24 hours) | Changes in suicidal ideation between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The BSS is a 19-item scale measuring suicidal ideation, with two additional items assessing a history of suicide attempts. Scores range from 0 to 38 with higher scores indicating higher severity of suicidal ideation. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Perceived Burdensomeness Visual Analogue Scale (PB-VAS) | Visits 2-5 (24 hours) | Changes in perceived burdensomeness between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The PB-VAS is a single-item visual analogue scale with the statement I feel like a burden where 0 indicates not at all and 100 indicates extremely. |
| Positive and Negative Affective Schedule (PANAS) | Visits 2-5 (24 hours) | Changes in positive and negative affect between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The PANAS is a 20-item scale measuring positive and negative affect with 10 items each. Scores range from 10 to 50 per domain (i.e. positive & negative affect) where higher scores indicate higher positive or negative affect, respectively. |
| Beck Hopelessness Scale (BHS) | Visits 2-5 (24 hours) | Changes in hopelessness between pre-stimulation (visit 2 and visit 4) and post-stimulation (visit 3 and visit 5), between- and within-person comparisons. The BHS is a 20-item scale measuring hopelessness. Scores range from 0 to 20 with higher scores indicating increased hopelessness |
| EEG: Individual alpha peak frequency | Visits 2 & 4 (up to 1 hour) | Changes in individual alpha peak frequency between pre- and post-stimulation at visit 2 (stimulation visit 1) and visit 4 (stimulation visit 2), between- and within-person comparisons. |
| EEG alpha power | Visits 2 & 4 (up to 1 hour) | Changes in EEG alpha power between pre- and post-stimulation at visit 2 (stimulation visit 1) and visit 4 (stimulation visit 2), between- and within-person comparisons. |
Contacts
Primary ContactAnna Monn, M.Sc.
Outcome results
None listed