SmokingNCT04133376
Electronic Hookah and Endothelial Cell Function
A study testing Electronic hookah vaping with nicotine and Electronic hookah vaping without nicotine in people with Smoking and Endothelial Dysfunction, run by University of California, Los Angeles at 1 site in United States.
Trial summary
Electronic nicotine delivery systems (ENDS) are a rapidly growing global epidemic among adolescents and young adults. Unlike other ENDS such as e-cigarettes, e-hookahs are used through traditional water-pipes, allowing the vapor-containing nicotine, propylene glycol, glycerin, and flavorings-to pass through a… Read more about this study
- Who is it for?
- Ages 21 to 39 yearsHealthy volunteers can take part
- Conditions the study is for
- Smoking, Endothelial Dysfunction
- What is being tested?
- Electronic hookah vaping with nicotine and Electronic hookah vaping without nicotine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 33 participants
- Where
- 1 siteUnited States
- Study dates
- 16 Jan 2020to 29 May 2023
- Phase
- Interventional
- Are there results?
- None posted in the registry
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 21 to 39 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- 21-39 years old hookah smokers: smoked hookah >12x in last 12 months
- 21-39 years old e-cigarette users: vaped >12x in last 12 months
- no history of illicit drugs
- no evidence of cardiopulmonary disease by history/ physical
- no diabetes: fasting blood glucose <100 mg/dl
- BP<140/90mmHg
Show all 9Show fewer
- resting HR<100 bpm
- BMI<30kg•m2
- no prescription medication
Who cannot join
- exhaled CO>10 ppm (smoking non-abstinence)
- positive pregnancy test
- psychiatric illness
Trial locations and contacts
1 site in 1 country.
United States1 site
University of California, Los Angeles
Los Angeles, California, 90024
About this study
Official title: The Effects of Electronic Hookah on Endothelial Cell Function: The Role of Nicotine
Electronic nicotine delivery systems (ENDS) are a rapidly growing global epidemic among adolescents and young adults. Unlike other ENDS such as e-cigarettes, e-hookahs are used through traditional water-pipes, allowing the vapor-containing nicotine, propylene glycol, glycerin, and flavorings-to pass through a water-filled basin, potentially altering the vapor, before it is inhaled through the user's mouth. Contributing to e-hookahs popularity is the belief that the flavored smoke is detoxified as it passes through the water-filled basin, rendering e-hookah a safer tobacco alternative. However, an e-hookahs deliver flavored nicotine by creating a vapor of fine particles and volatile organic compounds that could induce vascular toxicity. While e-hookah vaping acutely reduces endothelial function, the specific role of nicotine and the mechanisms by which it may impairs endothelial function remain understudied. The objective of this project is to investigate the specific role of nicotine in mediating the acute effects of e-hookah vaping on endothelial dysfunction.
- Conditions
- Smoking, Endothelial Dysfunction
- Being tested
- Electronic hookah vaping with nicotine, Electronic hookah vaping without nicotine
- Medical subject headings
- Smoking
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Electronic hookah vaping with nicotineOther
Participants will be invited to vape a 30-minute session of e-hookah containing nicotine
Electronic hookah vaping without nicotineOther
Participants will be invited to vape a 30-minute session of e-hookah without containing nicotine
| Study group | Role | What they receive |
|---|---|---|
| e-hookah vaping with nicotine | Experimental | Participants were invited to vape a 30-minute electronic hookah with nicotine vaping session, followed by a 30-minute electronic hookah without nicotine vaping session.
To mitigate the impact of carryover effects, the two sessions were separated by a minimum of 7-days. Receives: Other: Electronic hookah vaping with nicotine; Other: Electronic hookah vaping without nicotine |
| e-hookah vaping without nicotine | Experimental | Participants were invited to vape a 30-minute electronic hookah without nicotine vaping session, followed by a 30-minute electronic hookah with nicotine vaping session.
To mitigate the impact of carryover effects, the two sessions were separated by a minimum of 7-days. Receives: Other: Electronic hookah vaping with nicotine; Other: Electronic hookah vaping without nicotine |
What is being measured
The primary outcome is the main question the study is designed to answer.
Flow-Mediated Dilation (FMD)
Using ultrasound, FMD of the brachial artery induced by reactive hyperemia, was used to measure endothelium-dependent vasodilator function. Outcome variable reflecting FMD (brachial artery diameter) was recorded for 45 seconds and resumed 30 seconds before cuff deflation and continuously for 2 minutes after deflation to obtain true peak vasodilatory response.
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Acetylcholine-stimulated nitric oxide production
Human umbilical vein endothelial cells were cultured with subjects' serum sampled before and after the vaping sessions and acetylcholine-stimulated nitric oxide production was assessed
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Basal reactive oxygen species bioactivity
Human umbilical vein endothelial cells were cultured with participants' serum sampled before and after the vaping sessions and basal reactive oxygen species bioactivity was assessed
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Fibrinogen levels
Plasma fibrinogen
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Heme oxygenase-1 assay
Heme oxygenase-1 concentration assay
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
paraoxonase-1 activity
paraoxonase-1 activity
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
HDL protection assay
HDL protection assay, reflecting the ability of HDL to inhibit oxidation to LDL
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Nicotine levels
Plasma nicotine
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Carbon monoxide levels
Exhaled carbon monoxide levels
Measured: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Oct 2019
- Study start16 Jan 2020
- Primary completion29 Nov 2022
- Study completion29 May 2023
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for SmokingStudies of the same condition, open and under way.
- More trials run by University of California, Los AngelesThe 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Enrolment
- 33 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of California, Los Angeles
- Sponsor type
- University, hospital or other
- Collaborators
- Tobacco Related Disease Research Program
- Responsible party
- Principal investigator, Mary Rezk-Hanna, PhD, University of California, Los Angeles
- Investigators
- Mary Rezk-Hanna, PhD, Principal investigator, University of California, Los Angeles
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04133376
- Sponsor's protocol ID
- T30IP1013
- Status last verified
- Mar 2026
- First submitted
- 17 Oct 2019
- Last updated
- 12 Mar 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 12 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effects of Electronic Hookah on Endothelial Cell Function: The Role of Nicotine
- ClinicalTrials.gov ID
- NCT04133376
- Acronym / sponsor ID
- T30IP1013
- Conditions
- Smoking, Endothelial Dysfunction
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 33 participants (actual)
- Lead sponsor
- University of California, Los AngelesUniversity, hospital or other
- Collaborators
- Tobacco Related Disease Research Program
- Study start
- 16 Jan 2020 (actual)
- Primary completion
- 29 Nov 2022 (actual)
- Study completion
- 29 May 2023 (actual)
- First posted
- 21 Oct 2019 (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.
Electronic nicotine delivery systems (ENDS) are a rapidly growing global epidemic among adolescents and young adults. Unlike other ENDS such as e-cigarettes, e-hookahs are used through traditional water-pipes, allowing the vapor-containing nicotine, propylene glycol, glycerin, and flavorings-to pass through a water-filled basin, potentially altering the vapor, before it is inhaled through the user's mouth. Contributing to e-hookahs popularity is the belief that the flavored smoke is detoxified as it passes through the water-filled basin, rendering e-hookah a safer tobacco alternative. However, an e-hookahs deliver flavored nicotine by creating a vapor of fine particles and volatile organic compounds that could induce vascular toxicity. While e-hookah vaping acutely reduces endothelial function, the specific role of nicotine and the mechanisms by which it may impairs endothelial function remain understudied. The objective of this project is to investigate the specific role of nicotine in mediating the acute effects of e-hookah vaping on endothelial dysfunction.
Study design
- Primary purpose
- Other
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| e-hookah vaping with nicotine | Experimental | Other: Electronic hookah vaping with nicotine, Other: Electronic hookah vaping without nicotineParticipants were invited to vape a 30-minute electronic hookah with nicotine vaping session, followed by a 30-minute electronic hookah without nicotine vaping session. To mitigate the impact of carryover effects, the two sessions were separated by a minimum of 7-days. |
| e-hookah vaping without nicotine | Experimental | Other: Electronic hookah vaping with nicotine, Other: Electronic hookah vaping without nicotineParticipants were invited to vape a 30-minute electronic hookah without nicotine vaping session, followed by a 30-minute electronic hookah with nicotine vaping session. To mitigate the impact of carryover effects, the two sessions were separated by a minimum of 7-days. |
Who may qualify
- Ages
- 21 to 39 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (9 listed)
- 21-39 years old hookah smokers: smoked hookah >12x in last 12 months
- 21-39 years old e-cigarette users: vaped >12x in last 12 months
- no history of illicit drugs
- no evidence of cardiopulmonary disease by history/ physical
- no diabetes: fasting blood glucose <100 mg/dl
Key exclusion criteria (3 listed)
- exhaled CO>10 ppm (smoking non-abstinence)
- positive pregnancy test
- psychiatric illness
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Electronic hookah vaping with nicotineParticipants will be invited to vape a 30-minute session of e-hookah containing nicotine | Other | e-hookah vaping with nicotine, e-hookah vaping without nicotine |
| Electronic hookah vaping without nicotineParticipants will be invited to vape a 30-minute session of e-hookah without containing nicotine | Other | e-hookah vaping with nicotine, e-hookah vaping without nicotine |
Primary outcome
Flow-Mediated Dilation (FMD)
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Using ultrasound, FMD of the brachial artery induced by reactive hyperemia, was used to measure endothelium-dependent vasodilator function. Outcome variable reflecting FMD (brachial artery diameter) was recorded for 45 seconds and resumed 30 seconds before cuff deflation and continuously for 2 minutes after deflation to obtain true peak vasodilatory response.
Acetylcholine-stimulated nitric oxide production
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Human umbilical vein endothelial cells were cultured with subjects' serum sampled before and after the vaping sessions and acetylcholine-stimulated nitric oxide production was assessed
Basal reactive oxygen species bioactivity
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Human umbilical vein endothelial cells were cultured with participants' serum sampled before and after the vaping sessions and basal reactive oxygen species bioactivity was assessed
Fibrinogen levels
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Plasma fibrinogen
Heme oxygenase-1 assay
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Heme oxygenase-1 concentration assay
paraoxonase-1 activity
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
paraoxonase-1 activity
HDL protection assay
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
HDL protection assay, reflecting the ability of HDL to inhibit oxidation to LDL
Nicotine levels
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Plasma nicotine
Carbon monoxide levels
Time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions
Exhaled carbon monoxide levels
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 12 Mar 2026.
- Individual participant dataSharing planned: Undecided
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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. This study is not recruiting at the moment.
Mary Rezk-Hanna, PhD principal investigator
University of California, Los Angeles
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Electronic hookah vaping with nicotine and Electronic hookah vaping without nicotine in people with Smoking and Endothelial Dysfunction, run by University of California, Los Angeles at 1 site in United States.
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 3 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: finished, as of the sponsor's last update on 12 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
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?
Flow-Mediated Dilation (FMD) (time frame: Changes pre- and post- the 30-minute smoking or vaping exposure sessions). The study lists 9 primary outcomes in all. 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 12 Mar 2026.