Major Depressive DisorderNCT07910318
Neurostructural and Biochemical Signatures of Tobacco Smoking in Mood Disorders
An observational study of Major Depressive Disorder and Bipolar Disorder, run by Assiut University.
Trial summary
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. Read more about this study
- Who is it for?
- Ages 18 to 45 years, men only
- Conditions the study is for
- Major Depressive Disorder, Bipolar Disorder, Tobacco Use Disorder
- How many people
- 240 participants
- Where
- No sites listed yet
- Study dates
- Nov 2026to Dec 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 45 years
- Men only
- Adult
Study population: Patients diagnosed with major depressive disorder (in remission) or bipolar disorder recruited consecutively from the inpatient wards and outpatient clinics of the Neuropsychiatry Department at Assiut University Hospitals (Assiut, Egypt). Healthy comparison controls are recruited from hospital staff relatives and community advertisements, frequency-matched to clinical cohorts by age, sex, and years of formal education. All participants are adult males aged 18 to 45 years.
Who may be able to join
- 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:
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- Current active, chronic tobacco cigarette smoker.
- Lifetime never-smoker.
- Capable of providing written informed consent and undergoing study assessments.
Who cannot join
- 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).
- Intellectual disability (IQ < 70).
- Treatment with electroconvulsive therapy (ECT) within the preceding 6 months.
- Standard contraindications to magnetic resonance imaging (MRI), including cardiac pacemakers, ferromagnetic or metallic orthopedic implants, severe claustrophobia, or inability to remain still during scanning.
About this study
Official title: Neurostructural and Biochemical Signatures of Tobacco Smoking in Mood Disorders: A Case-Control Study
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).
Read more
The study will enroll 240 male participants aged 18 to 45 years across six equal groups:
- Major depressive disorder (in remission) who are current smokers
- Major depressive disorder (in remission) who are lifetime never-smokers
- Bipolar disorder who are current smokers
- Bipolar disorder (in remission) who are lifetime never-smokers
- Healthy controls who are current smokers
- 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.
- Keywords
- Magnetic Resonance Imaging, Neurofilament Light Chain, Kynurenine Pathway, Cotinine, Tryptophan, Hippocampus, Insular Cortex, Nicotine Dependence
- Medical subject headings
- Depressive Disorder, Major, Bipolar Disorder, Tobacco Use Disorder, Mood Disorders, Charcot-Marie-Tooth disease, Type 1F
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| MDD in Remission - Current Smokers | Male patients aged 18-45 years with a confirmed diagnosis of Major Depressive Disorder currently in clinical remission who are active, chronic tobacco cigarette smokers (n = 40). | |
| MDD in Remission - Never-Smokers | Male patients aged 18-45 years with a confirmed diagnosis of Major Depressive Disorder currently in clinical remission who have never smoked tobacco (lifetime never-smokers) (n = 40). | |
| Bipolar Disorder - Current Smokers | Male patients aged 18-45 years with a confirmed diagnosis of Bipolar Disorder (euthymic/in remission or manic/hypomanic) who are active, chronic tobacco cigarette smokers (n = 40). | |
| Bipolar Disorder in Remission - Never-Smokers | Male patients aged 18-45 years with a confirmed diagnosis of Bipolar Disorder currently in clinical remission who have never smoked tobacco (lifetime never-smokers) (n = 40). | |
| Healthy Controls - Current Smokers | Healthy male individuals aged 18-45 years with no history of psychiatric or neurological disorders who are active, chronic tobacco cigarette smokers, frequency-matched to patients on age and education (n = 40). | |
| Healthy Controls - Never-Smokers | Healthy male individuals aged 18-45 years with no history of psychiatric or neurological disorders who have never smoked tobacco (lifetime never-smokers), frequency-matched to patients on age and education (n = 40). |
What is being measured
The primary outcome is the main question the study is designed to answer.
Normalized Hippocampal Volume
Normalized bilateral hippocampal volume measured in cubic millimeters (mm³) using 1.5 Tesla structural magnetic resonance imaging (MRI) and normalized to estimated total intracranial volume (eTIV). Volumetric segmentation is evaluated to determine differences across diagnostic and smoking status groups.
Measured: Baseline
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Nov 2026
- Study startNov 2026 (estimated)
- Primary completionNov 2027 (estimated)
- Study completionDec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Major Depressive DisorderStudies of the same condition, open and under way.
- More trials run by Assiut UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Enrolment
- 240 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Assiut University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Amaal Emad Khairy, Assiut University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07910318
- Sponsor's protocol ID
- Tobacco in Mood Disorders
- Status last verified
- Oct 2026
- First submitted
- 27 Oct 2026
- Last updated
- 2 Nov 2026
- Results posted
- No
Study at a glance
From the registry record, last updated by the sponsor on 2 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Neurostructural and Biochemical Signatures of Tobacco Smoking in Mood Disorders: A Case-Control Study
- ClinicalTrials.gov ID
- NCT07910318
- Acronym / sponsor ID
- Tobacco in Mood Disorders
- Keywords
- Magnetic Resonance Imaging, Neurofilament Light Chain, Kynurenine Pathway, Cotinine, Tryptophan, Hippocampus, Insular Cortex, Nicotine Dependence
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 240 participants (estimated)
- Lead sponsor
- Assiut UniversityUniversity, hospital or other
- Study start
- Nov 2026 (estimated)
- Primary completion
- Nov 2027 (estimated)
- Study completion
- Dec 2027 (estimated)
- First posted
- 2 Nov 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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:
- Major depressive disorder (in remission) who are current smokers
- Major depressive disorder (in remission) who are lifetime never-smokers
- Bipolar disorder who are current smokers
- Bipolar disorder (in remission) who are lifetime never-smokers
- Healthy controls who are current smokers
- 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.
Study design
- Observational model
- Case-control
- Time perspective
- Cross-sectional
- Number of arms
- 6
| Arm | Type | Receives |
|---|---|---|
| MDD in Remission - Current Smokers | – | –Male patients aged 18-45 years with a confirmed diagnosis of Major Depressive Disorder currently in clinical remission who are active, chronic tobacco cigarette smokers (n = 40). |
| MDD in Remission - Never-Smokers | – | –Male patients aged 18-45 years with a confirmed diagnosis of Major Depressive Disorder currently in clinical remission who have never smoked tobacco (lifetime never-smokers) (n = 40). |
| Bipolar Disorder - Current Smokers | – | –Male patients aged 18-45 years with a confirmed diagnosis of Bipolar Disorder (euthymic/in remission or manic/hypomanic) who are active, chronic tobacco cigarette smokers (n = 40). |
| Bipolar Disorder in Remission - Never-Smokers | – | –Male patients aged 18-45 years with a confirmed diagnosis of Bipolar Disorder currently in clinical remission who have never smoked tobacco (lifetime never-smokers) (n = 40). |
| Healthy Controls - Current Smokers | – | –Healthy male individuals aged 18-45 years with no history of psychiatric or neurological disorders who are active, chronic tobacco cigarette smokers, frequency-matched to patients on age and education (n = 40). |
| Healthy Controls - Never-Smokers | – | –Healthy male individuals aged 18-45 years with no history of psychiatric or neurological disorders who have never smoked tobacco (lifetime never-smokers), frequency-matched to patients on age and education (n = 40). |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- Male only
- Age groups
- Adult
- Study population
- Patients diagnosed with major depressive disorder (in remission) or bipolar disorder recruited consecutively from the inpatient wards and outpatient clinics of the Neuropsychiatry Department at Assiut University Hospitals (Assiut, Egypt). Healthy comparison controls are recruited from hospital staff relatives and community advertisements, frequency-matched to clinical cohorts by age, sex, and years of formal education. All participants are adult males aged 18 to 45 years.
Key inclusion criteria (9 listed)
- Male sex, aged 18 to 45 years.
- Belongs to one of the target diagnostic categories:
- Smoking exposure status meeting one of the predefined criteria:
- Capable of providing written informed consent and undergoing study assessments.
Key exclusion criteria (5 listed)
- 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).
- Intellectual disability (IQ < 70).
- Treatment with electroconvulsive therapy (ECT) within the preceding 6 months.
- Standard contraindications to magnetic resonance imaging (MRI), including cardiac pacemakers, ferromagnetic or metallic orthopedic implants, severe claustrophobia, or inability to remain still during scanning.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Normalized Hippocampal Volume
Time frame: Baseline
Normalized bilateral hippocampal volume measured in cubic millimeters (mm³) using 1.5 Tesla structural magnetic resonance imaging (MRI) and normalized to estimated total intracranial volume (eTIV). Volumetric segmentation is evaluated to determine differences across diagnostic and smoking status groups.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Nov 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
An observational study of Major Depressive Disorder and Bipolar Disorder, run by Assiut University.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 9 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 2 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Normalized Hippocampal Volume (time frame: Baseline). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Nov 2026.