Neurobiology of Suicide

• Status: Recruiting
• Trial end date: 2025-07-21
• Target enrollment: 0
• Participant gender: All

Summary

Background:

There are no good treatments for people considering suicide. Researchers want to study suicide with questions, blood tests, brain imaging, and sleep studies. They hope to better understand suicide, so they can help suicidal people.

Objective:

To understand what happens in the brain when someone has thought about or attempted suicide.

Eligibility:

Group 1: Adults ages 18 70 who have thought about or attempted suicide recently

Group 2: Adults ages 18 70 who have thought about or attempted suicide in the past

Group 3: Adults ages 18 70 who have depression or anxiety, but have never thought about suicide

Group 4: Healthy volunteers the same ages.

Design:

Participants will be screened in another protocol. Adults who have recently thought about or attempted suicide must be referred by a doctor. They may do up to 3 phases of this study. Groups 2, 3 and 4 will do only Phase 1 and will not get ketamine.

Phase 1: 1 week in hospital. Participants will have:

Physical exam.

Questions about thoughts and feelings.

Thinking and memory tests and simple tasks.

Blood and urine tests.

Two MRI scans. Participants will lie on a table that slides into a metal cylinder that takes pictures. They will have a coil over their head and earplugs and do a computer task.

Sleep test. Disks and bands will be placed on the body to monitor it during sleep.

Magnetic detectors on their head while they perform tasks.

A wrist monitor for activity and sleep.

Lumbar puncture (optional). A needle will collect fluid from the back.

Shock experiments (optional). Participants will observe pictures and sounds and feel a small shock on the hand.

Phase 2: 4 days in hospital. A thin plastic tube will be placed in each arm, one for blood draws, the other to get the drug ketamine once. Participants will repeat most of the Phase 1 tests.

Phase 3: up to 4 more ketamine doses over 2 weeks.

Participants will have follow-up calls or visits at 6 months and then maybe yearly for 5 years.

• Phase: Phase 2
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: National Institute of Mental Health (NIMH)
• Treatments: Ketamine

Criteria

• INCLUSION CRITERIA:

Phase I: Groups 1-3 and 5 (Patients)

1. 18 to 70 years of age.

2. A level of understanding sufficient to agree to all required tests and examinations, sign an informed consent document and verify understanding by a score greater than or equal to 90% on the Baseline consent quiz

3. Individuals who are able to get pregnant must be willing to remain sexually abstinent or use at least one form of effective birth control during participation in Phase I.

4. Additional Criteria for Group 1 (Active Crisis): Agree to be hospitalize

Phase I: Group 4 (Healthy Volunteers)

1. 18 to 70 years of age.

2. A level of understanding sufficient to agree to all required tests and examinations, sign an informed consent document.

3. Individuals who are able to get pregnant must be willing to remain sexually abstinent or use at least one form of effective birth control during participation in Phase I.

Phase II: Group 1 (Active Crisis) and Group 5 (Suicide Ideators)

1. Patients must have completed Study Phase I as a participant in Group 1

2. Participants must verify understanding of the protocol by a score greater than or equal to 80% on the Ketamine Response

consent quiz.

3. Patients in Group 1 or 5 must report at least minimal suicidal ideation, depressive or anxiety symptoms to be eligible for this phase (see Monitoring Suicide Risk section).

• MADRS score of over 10 (10 used as an outcome measure for remission)126

• OR HAMA score of over 7 (7 used as an outcome measure for remission)127

• OR SSI score of 2 or more (indicates any residual suicidal thoughts)

4. Individuals who are able to get pregnant must be willing to remain sexually abstinent or use at least one form of effective birth control during participation in Phase II.

Phase III: Group 1 (Active Crisis) and Group 5 (Suicide Ideators)

1. Participants must have met all inclusion criteria for and completed Study Phase II as a participant in Group 1 (active crisis) or Group 5 (Suicide Ideators).

2. Individuals who are able to get pregnant must be willing to remain sexually abstinent or use at least one form of effective birth control during participation in Phase III.

EXCLUSION CRITERIA:

Phase I: Groups 1-3 and 5 (Patients)

1. Current psychotic features or cognitive impairment that would preclude understanding of the consenting process or tests/examinations.

2. Current drug or alcohol dependence

3. Currently intoxicated or under the acute effects of an illicit substance will not be consented into the study.

4. Pregnant or nursing individuals or those who plan to become pregnant.

5. Serious, unstable medical conditions/problems including hepatic, renal, gastroenterologic, respiratory, cardiovascular (including blood pressure, ischemic heart disease), endocrinologic, neurologic, immunologic, or hematologic disease.

6. Clinically significant abnormal laboratory tests.

7. Positive HIV test

8. Participants who, in the investigator s judgment, pose a current homicidal risk or pose suicide risk that cannot be managed in a secure, voluntary inpatient setting.

9. Non-English speakers

10. Additional Criteria for Group 1 (Active Crisis): For participants who still experience the effects of their suicide attempt, i.e. someone who overdosed is significantly drowsy or confused, the consenting process will occur after the patient has improved from the effects. If there is a concern around a participant s capacity to consent, the Human Subjects Protections Unit (HSPU) team member who is

monitoring the informed consent process will complete a capacity assessment. Participants who are determined not to have capacity to consent to research will not be included in the study.

Phase I: Group 4 (Healthy Volunteers)

1. Current or past Axis I diagnosis

2. Presence of medical illness likely to alter brain morphology and/or physiology (e.g., hypertension, diabetes) even if controlled by medications.

3. Current or past alcohol or substance abuse or dependence diagnosis (except for nicotine or caffeine) (or substance abuse disorder per DSM-V).

4. Presence of psychiatric disorders or a history of suicide attempt or death in first-degree relatives.

5. Pregnant or nursing individuals or those who plan to become pregnant.

6. No lifetime suicide attempts or ideations

7. Non-English speakers

8. Positive HIV test

Exclusions for Imaging:

1. Participants with metal objects implanted in the body, such as aneurysm clips, neural stimulators, implanted cardiac pacemakers, or auto-defibrillator, cochlear implant, or ocular foreign body which would make having an MRI scan unsafe

2. Participants who are uncomfortable in small closed spaces (have claustrophobia) and would feel uncomfortable in the MRI machine

3. Participants with a brain abnormality on an initial MRI scan

4. Subjects with hearing loss that has been clinically evaluated and diagnosed and may be worsened through participation in imaging procedures

Phase II: Group 1 (Active Crisis) and Group 5 (Suicide Ideators)

1. Treatment with a reversible MAOI within 2 weeks prior to study Phase II.

2. Treatment with any other concomitant medication not allowed within 5 (Omega) half-lives prior to study Phase II.

3. Subjects with one or more seizures without a clear and resolved etiology

4. Participants with a positive urine for an illicit substance no more than 24 hours prior to the ketamine infusion.

5. Presence of current psychotic features or a diagnosis of Schizophrenia or any other psychotic disorder as defined in the DSM-IV or DSM-V

6. Pregnant or nursing individuals or those who plan to become pregnant.

7. A medical finding or condition that in the clinical judgement of the investigator increases the risk of adverse effects from the ketamine administration (for example: findings suggesting difficulties with kidney or cardiac function that may be contraindications for an experimental intervention).

Phase III: Repeated Administration (Group 1) and Group 5 (Suicide Ideators)

1. Intolerable or serious adverse reaction to ketamine during Phase II

2. Treatment with a reversible MAOI within 2 weeks prior to study Phase III.

3. Treatment with any other concomitant medication not allowed within 5 (Omega) half-lives prior to study Phase III.

4. Subjects with one or more seizures without a clear and resolved etiology

5. Participants with a positive urine for an illicit substance no more than 24 hours prior to each ketamine infusion.

6. Presence of current psychotic features or a diagnosis of Schizophrenia or any other psychotic disorder as defined in the DSM-IV or DSM-V

7. Pregnant or nursing individuals or those who plan to become pregnant.

Exclusions for Imaging:

1. Participants with metal objects implanted in the body, such as aneurysm clips, neural stimulators, implanted cardiac pacemakers, or auto-defibrillator, cochlear implant, or ocular foreign body which would make having an MRI scan unsafe

2. Participants who are uncomfortable in small closed spaces (have claustrophobia) and would feel uncomfortable in the MRI machine

3. Participants with a brain abnormality on an initial MRI scan

4. Subjects with hearing loss that has been clinically evaluated and diagnosed and may be worsened through participation in imaging procedures