NCT07910318Not yet recruiting
Neurostructural and Biochemical Signatures of Tobacco Smoking in Mood Disorders
Neurostructural and Biochemical Signatures of Tobacco Smoking in Mood Disorders: A Case-Control Study
Source: ClinicalTrials.gov · Last updated 2 Nov 2026
Brief summary (registry, in English)
Tobacco smoking is significantly more common among individuals with mood disorders, such as major depressive disorder (MDD) and bipolar disorder, compared to the general population. Chronic smoking in these conditions is often linked to more severe symptoms, frequent episodes, and reduced overall quality of life. However, the biological mechanisms linking tobacco smoking to brain alterations and clinical outcomes in mood disorders remain incompletely understood. The primary purpose of this study is to examine whether chronic tobacco cigarette smoking is associated with alterations in brain structure, specifically regional brain volumes including the hippocampus and insula, and circulating biochemical markers of neuronal injury (neurofilament light chain \[NfL\]) and neurobiological pathways (tryptophan and kynurenic acid). The study will enroll 240 male participants aged 18 to 45 years across six equal groups: 1. Major depressive disorder (in remission) who are current smokers 2. Major depressive disorder (in remission) who are lifetime never-smokers 3. Bipolar disorder who are current smokers 4. Bipolar disorder (in remission) who are lifetime never-smokers 5. Healthy controls who are current smokers 6. Healthy controls who are lifetime never-smokers Participants will take part in a single study visit involving: * Clinical assessments and psychiatric rating scales evaluating mood symptoms, cognition, personality traits, and smoking history. * Routine physical and vital sign measurements. * A fasting morning blood draw to evaluate serum biomarkers (NfL, tryptophan, kynurenic acid) and confirm tobacco exposure via serum cotinine. * A structural brain magnetic resonance imaging (MRI) scan to measure regional brain volumes.
- Status (registry)
- Not yet recruiting
- Study type
- Observational
- Enrollment
- 240 (estimated)
- First submitted
- 27 Oct 2026
- Start date
- 1 Nov 2026
- Primary completion date
- 30 Nov 2027
- Lead sponsor
- Assiut University
- Diseases
- Depression, Bipolar disorder
- NCT number
- NCT07910318
What you commit to
- Study type: Observational
- Planned participants: 240
- From 1 Nov 2026 to the primary completion date, 30 Nov 2027
- No sites listed in no country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Treatment with electroconvulsive therapy (ECT) within the preceding 6 months.
Other illness
- Pre-existing neurological disorders or psychiatric disorders other than the target mood disorder.
- Any current substance use disorder other than tobacco (caffeine use is permitted).
- Standard contraindications to magnetic resonance imaging (MRI), including cardiac pacemakers, ferromagnetic or metallic orthopedic implants, severe claustrophobia, or inability to remain still during scanning.
Other
- Intellectual disability (IQ \< 70).
Who the study is looking for
- Male sex, aged 18 to 45 years.
- Belongs to one of the target diagnostic categories:
- Major Depressive Disorder (currently in clinical remission).
- Bipolar Disorder (in clinical remission/euthymic or manic/hypomanic).
- Healthy control with no personal history of psychiatric or neurological disorders (frequency-matched on age and education).
- Smoking exposure status meeting one of the predefined criteria:
- Current active, chronic tobacco cigarette smoker.
- Lifetime never-smoker.
- Capable of providing written informed consent and undergoing study assessments.
Age in the registry: 18 years to 45 years · Sex: Male
This page is information, not medical advice. Discuss any trial with your doctor.