Effects of electronic cigarettes and traditional cigarettes on brain structures
| ISRCTN | ISRCTN26393895 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN26393895 |
| Sponsor | Erciyes University |
| Funder | Bilimsel Araştırma Projeleri, Erciyes Üniversitesi |
- Submission date
- 04/06/2026
- Registration date
- 05/06/2026
- Last edited
- 05/06/2026
- Recruitment status
- Not yet recruiting
- Overall study status
- Ongoing
- Condition category
- Nervous System Diseases
Plain English summary of protocol
Background and study aims
Smoking traditional cigarettes is known to affect the brain, but less is known about how electronic cigarettes, also called vaping, may change brain structure. This study aims to compare the brains of young adults aged 18 years to 30 years who use electronic cigarettes, those who smoke traditional cigarettes, and those who do not smoke at all. The researchers will look at differences in brain size, structure, and connections using brain scans.
Who can participate?
Healthy adults aged between 18 years and 30 years can take part. Participants must fall into one of three groups: people who have used only electronic cigarettes for at least 1 year, people who have smoked only traditional cigarettes for at least 1 year, or people who do not use any nicotine, tobacco, alcohol, or illicit drugs. Participants must not have serious medical, neurological, or psychiatric conditions and must be able to safely undergo an MRI scan.
What does the study involve?
Participants will first complete questionnaires about smoking habits and nicotine dependence. They will then have a brain scan using magnetic resonance imaging, also known as MRI. The scan does not use radiation, involves no injections, and is not painful. It takes about 30 minutes to 40 minutes. During the scan, participants lie still while detailed images of the brain are taken.
What are the possible benefits and risks of participating?
There are no direct health benefits for participants. However, the study may help researchers better understand how vaping and smoking affect the brain, which could benefit public health in the future. The risks are low. MRI scans are widely used and safe for most people, but some individuals cannot take part if they have certain metal implants or similar conditions.
Where is the study run from?
The study is run from Erciyes University, Faculty of Medicine in Kayseri, Türkiye.
When is the study starting and how long is it expected to run for?
The study is expected to begin recruitment on 01 July 2026 and continue until 01 October 2026. The overall study is expected to run until 01 July 2027.
Who is funding the study?
The study is funded by the Scientific Research Projects body at Erciyes University in Türkiye.
Who is the main contact?
Dr İzzet Ökçesİz at Erciyes University, izzetokcesiz@erciyes.edu.tr
Contact information
Principal investigator
Köşk, Fakülte İçi Küme Evleri No:30, 38030 Melikgazi/Kayseri
Kayseri
38038
Türkiye
 ORCID ID |
0000-0002-0257-1769 |
|---|---|
| Phone | +90 505 800 38 37 |
| izzetokcesiz@erciyes.edu.tr |
Scientific, Public
Talas, Kayseri
Talas
38280
Türkiye
| ORCID ID |
0000-0002-7739-9844 |
|---|---|
| Phone | +905313741235 |
| huseyin.yigit@kapadokya.edu.tr |
Study information
| Primary study design | Observational |
|---|---|
| Observational study design | Cohort study |
| Scientific title | Brain morphometry in electronic cigarette and traditional cigarette users: an MRI-based analysis |
| Study acronym | EC-TC-BRAIN |
| Study objectives | The primary objective of this study is to investigate the morphometric changes occurring in the brains of young adult individuals as a result of exposure to electronic cigarettes (EC) and traditional cigarettes (TC). To achieve this purpose, structural and quantitative parameters—including brain volume, cortical thickness, white matter tracts (tractography), and olfactory-related tracts—will be compared among three distinct groups: exclusive electronic cigarette users, exclusive traditional cigarette users, and healthy non-smoking controls. |
| Ethics approval(s) |
Approved 24/12/2025, ERCIYES ÜNİVERSİTESİ SAĞLlK BiLiMLERi ARAŞTIRMA ETiK KURULU (Erciyes Üniversitesi Tıp Fakültesi Dekanlığı Melikgazi/KAYSERİ, Kayseri, 38038, Türkiye; +90 352207 66 66 - 23031; serifeserim@erciyes.edu.tr), ref: 2025/613 |
| Health condition(s) or problem(s) studied | Neurotoxicity, brain morphometric and structural changes associated with electronic cigarette (vaping) and traditional cigarette use in young adults. |
| Intervention | Participant Selection and Grouping Participants will be screened and classified into three distinct groups (n=25 per group, total N=75) based on specialized dependency scales and explicit inclusion/exclusion criteria: Electronic Cigarette (EC) group, Traditional Cigarette (TC) group, and a Healthy Control group. The classification and characterization will be performed using the Fagerström Test for Nicotine Dependence, the Penn State Electronic Cigarette Dependence Index, the E-Cigarette Dependence Scale, and the Sensory E-Cigarette Expectations Scale. Written informed consent will be obtained from all individuals prior to enrollment. MRI Acquisition Protocol All cranial imaging will be performed using a 3.0 Tesla superconducting MRI scanner (Ingenia, Philips) equipped with a 16-channel head coil. Participants will be scanned in the supine position without sedation and without the administration of contrast agents. The total scan duration will be approximately 30–40 minutes per participant, utilizing the following sequences: T1-Weighted 3D Volumetric Data: Field of View (FOV) = 240 mm, slice thickness = 1 mm, spacing between slices = 0.5 mm, Number of Averages = 2, repetition time (TR) = 6.7 ms, and echo time (TE) = 3.0 ms. Diffusion Tensor Imaging (DTI): Axial acquisition, TR = 3260 ms, TE = 85 ms, FOV = 240 mm, slice thickness = 2.5 mm, spacing between slices = 2.5 mm, Number of Averages = 2, b-value = 1000 s/mm², acquired along 32 non-collinear diffusion-sensitizing directions. Image Processing and Volumetric Analysis Raw MRI data in DICOM format will be converted using Radiant DICOM Viewer and MRIcroGL software into NIfTI format (.nii.gz). For brain volumetry, NIfTI files will be uploaded to the vol2brain (volBrain) cloud-based, artificial intelligence-driven automated pipeline. This pipeline will automatically segment and calculate the volumes of 135 distinct brain regions, alongside macrostructural estimations of hippocampal subfields, brain structures age, cerebellar compartments, and cortical thickness metrics. White Matter Tractography Analysis Diffusion data processing and fiber tracking will be executed via DSI Studio software. Prior to reconstruction, tractography parameters will be uniformly configured as follows: Quantitative Anisotropy (QA) threshold = 0.20, Angular Threshold = 70 degrees, Smoothing = 0.50, minimum fiber length = 10 mm, maximum fiber length = 1000 mm, and a termination criterion of 100,000 tracts. Target white matter tracts will be tracked bilaterally. Quantitative microstructural metrics including total fiber count, mean fiber length (mm), fiber ratio (percentage of tract-specific fibers relative to whole-brain fibers), Fractional Anisotropy (FA), Mean Diffusivity (MD), Axial Diffusivity (AD), and Radial Diffusivity (RD) will be exported for statistical comparison. Statistical Analysis Statistical evaluations will be conducted using SPSS 25.0 and GraphPad Prism 10 softwares. Data normality will be verified using the Shapiro-Wilks test. Continuous variables showing normal distribution will be compared between two groups using the Student’s t-test, while non-normally distributed data will be assessed using the Mann-Whitney U test. For multi-group comparisons (three groups), One-Way ANOVA or the Kruskal-Wallis H test will be implemented depending on the distribution properties. Relationships between behavioral scale metrics and morphometric imaging indices will be assessed via Pearson correlation analysis. Statistical significance will be set at p < 0.05. |
| Intervention type | Other |
| Primary outcome measure(s) |
|
| Key secondary outcome measure(s) |
|
| Completion date | 01/07/2027 |
Eligibility
| Participant type(s) | |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Upper age limit | 30 Years |
| Sex | All |
| Target sample size at registration | 75 |
| Total final enrolment | 75 |
| Key inclusion criteria | 1. Aged between 18 years and 30 years (both sexes included) 2. No known history of central nervous system disease 3. No known chronic systemic diseases (e.g., hypertension, diabetes, metabolic syndrome) 4. No contraindications for MRI scanning (e.g., metallic implants, cardiac pacemakers, neurostimulators, or severe claustrophobia) 5. Capable of giving written informed consent 6. Good MRI image quality without severe motion artifacts 7. Group-specific criteria: 7.1. Minimum 1 year of continuous exclusive use for the EC or TC groups 7.2. Absolute non-use of any nicotine or tobacco products, alcohol, or illicit substances for the healthy control group |
| Key exclusion criteria | 1. History of serious neurological disease (e.g., epilepsy, cerebrovascular events) 2. Severe or unstable psychiatric disorders (e.g., major depressive disorder, schizophrenia, bipolar disorder) 3. Diagnoses affecting brain structure or development, such as ADHD 4. Alcohol or illicit substance use disorder, or active use within the past year 5. Dependence on substances other than nicotine 6. Extremely high or low body mass index (BMI) that could independently influence brain volume 7. Metabolic or chronic inflammatory diseases (e.g., uncontrolled diabetes) 8. Regular use of medications affecting central nervous system activity or structure (e.g., psychotropics, chronic steroids) 9. Pregnancy or lactation 10. Dual users (simultaneous users of both electronic and traditional cigarettes) |
| Date of first enrolment | 01/07/2026 |
| Date of final enrolment | 01/10/2026 |
Locations
Countries of recruitment
- Türkiye
Study participating centres
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|
Editorial Notes
04/06/2026: Trial's existence confirmed by Erciyes Üniversitesi.
