An observational study in Major Depressive Disorder, Bipolar Disorder and Tobacco Use Disorder, sponsored by Assiut University. Not yet recruiting. Open to male participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2026-11-02.
Sponsored by Assiut University · Observational
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:
Participants will take part in a single study visit involving:
3,041 studies on the registry are indexed under Depressive Disorder, Major; 588 are open to participants now.
This study's planned enrollment of 240 is above the median of 131 across 400 observational studies indexed under Depressive Disorder, Major.
Browse Depressive Disorder, Major studies →Assiut University is the lead sponsor of 5,078 studies on the registry; 2,178 are open to participants now.
Of its 14 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
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.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Belongs to one of the target diagnostic categories:
Smoking exposure status meeting one of the predefined criteria:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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).
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).
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).
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 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 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).
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.
Time frame: Baseline
No study locations are listed for this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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