Secondhand Effects of Hookah (i.e., Waterpipe) Smoke and Aerosol

NCT04661683 | Active Not Recruiting

• 1 other identifier: 20-001570
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

In the United States, secondhand smoke is the third leading preventable cause of death. Flavored hookah (waterpipe) tobacco smoking, a highly social activity common in hookah bars, is a key source of SHS exposure. While smoke-free air laws have decreased exposure to secondhand smoke, the majority of laws do not include hookah smoking. Thus, as a social outlet for youth and young adults, hookah smoke exposure may harm non-smokers, including women of reproductive age or pregnant, hookah bar workers, children, and individuals with heart and lung disease. While more is known on the acute effects of active hookah smoking and the literature is emerging on active e-hookah vaping, little is known about the acute vascular effects of secondhand exposure to hookah smoke and aerosol. The study aims to examine the acute effects of secondhand exposure of hookah smoke and aerosol on endothelial and vascular function. Eligible volunteers will be invited to participate in a total of 3 study visits (2-3 hours each): e-hookah aerosol exposure, charcoal-heated hookah smoke exposure and smoke-free room air. Non-invasive blood pressure and blood flow measurements will be taken before and after the exposure sessions.

Conditions

Secondhand Aerosol; Vascular Stiffness; Vaping; Hookah Smoking

Outcome Measures

Primary Outcomes (2)

• Flow-Mediated Dilation (FMD)

  Using ultrasound, FMD of the brachial artery induced by reactive hyperemia, will be used to measure endothelium-dependent vasodilator function. Baseline diameter and velocity will be recorded for 45 seconds and resumed 30 seconds before cuff deflation and continuously for 2 minutes after deflation to obtain true peak vasodilatory response.

  Pre- and post- the 60-minute exposure sessions

• Arterial stiffness

  Using applanation tonometry, pulse wave velocity will be used to measure cebtral arterial stiffness.

  Pre- and post- the 60-minute exposure sessions

Study Arms (3)

Exposure to Combustible Hookah Smoke

EXPERIMENTAL

Participants will be exposed to combustible hookah smoke. To mitigate the impact of carryover effects, the exposure sessions will be separated by a minimum of 7-days.

Other: Combustible Hookah Smoke

Exposure to Electronic Hookah Aerosol

EXPERIMENTAL

Participants will be exposed to electronic hookah aerosol. To mitigate the impact of carryover effects, the exposure sessions will be separated by a minimum of 7-days.

Other: Electronic Hookah Aerosol

Exposure to Clean Air

EXPERIMENTAL

Participants will be exposed to Clean Room Air. To mitigate the impact of carryover effects, the exposure sessions will be separated by a minimum of 7-days.

Other: Clean Room Air

Interventions

Combustible Hookah Smoke OTHER

Exposure to combustible hookah smoke for a duration of 60 minutes.

Exposure to Combustible Hookah Smoke

Electronic Hookah Aerosol OTHER

Exposure to electronic hookah aerosol for a duration of 60 minutes.

Exposure to Electronic Hookah Aerosol

Clean Room Air OTHER

Exposure to room air for a duration of 60 minutes.

Exposure to Clean Air

Eligibility Criteria

• Age: 21 Years - 49 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• years old
• Never a smoker: do not use any tobacco products or nicotine delivery systems, including cigarettes, cigars (traditional and filtered), cigarillos, hookah, smokeless tobacco (i.e., loose snus, moist snuff, dip, spit, or chewing tobacco), pipe tobacco, snus pouches, dissolvable tobacco or vaping.
• no evidence of cardiopulmonary disease by history/physical
• blood pressure (BP) \< 140/90 mmHg
• resting heart rate (HR) \< 100 bpm
• BMI \>18 or \< 30kg•m2
• no prescription medication
• No exposure to environmental tobacco smoke for at least one week prior to the study date.

You may not qualify if:

• exhaled carbon monoxide \>6 ppm
• (+) pregnancy test
• other conditions deemed unsafe to participate, such as breastfeeding

Sponsors & Collaborators

• University of California, Los Angeles: lead

Study Sites (1)

University of California, Los Angeles

Los Angeles, California, 90095-8361, United States

Location

MeSH Terms

Conditions

Water Pipe Smoking; Vaping

Condition Hierarchy (Ancestors)

Pipe Smoking; Smoking; Behavior

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: December 3, 2020
• First Posted: December 10, 2020
• Study Start: June 25, 2021
• Primary Completion (Estimated): December 15, 2026
• Study Completion (Estimated): April 15, 2027
• Last Updated: April 22, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)