The Cardiovascular Effects of Electronic Hookah Vaping

University of California, Los Angeles (UCLA)

Status: Completed

Conditions: Inflammation; Endothelial Dysfunction; Oxidative Stress

Treatments: Other: Traditional hookah smoking; Other: Electronic hookah vaping

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT03690427

1R21HL145002-01 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

Hookah (water-pipe) tobacco smoking has quickly grown to become a major global tobacco epidemic among youth; with electronic (e-) hookahs more recently increasing in popularity especially among young female adults, who endorse marketing claims that these products are a safer alternative to traditional hookah, but scientific evidence is lacking. The study aims to elucidate the comparative effects of traditional hookah smoking vs. e-hookah vaping on human vascular and endothelial function; and examine the role of inflammation and oxidative stress, as likely mechanisms in hookah-related cardiovascular disease pathogenesis.

Full description

Hookah (water-pipe) tobacco smoking is rapidly increasing in popularity worldwide. Contributing to this popularity is the unsubstantiated belief that traditional charcoal-heated hookah smoke is detoxified as it passes through the water-filled basin. More recently, electronic (e-) hookahs-containing flavored e-liquid that is heated electrically but inhaled through traditional water-pipes-are increasing in popularity in the United States among young female adults, who endorse marketing claims that these products are even safer than traditional charcoal-heated hookah products. The objective of this project is to investigate the comparative effects of traditional charcoal-heated hookah smoking versus e-hookah vaping on endothelial and vascular function and their mechanistic role in the development of cardiovascular disease. The investigators will test the hypothesis that: 1) in the absence of burning charcoal briquettes and virtually any carbon monoxide (CO) exposure, e-hookah vaping acutely impairs endothelial function and evokes acute central arterial stiffness, opposite from the endothelial function augmentation observed after traditional charcoal-heated hookah smoking, which is likely mediated by the large CO boost emitted from burning charcoal briquettes used to heat the flavored hookah tobacco; and 2) the processes of oxidative stress and inflammation play a pivotal mechanistic role underlying these vascular changes. Accordingly, in a cross-over study comparing traditional hookah smoking to e-hookah vaping, the investigators will assess endothelial function measured by brachial artery flow-mediated dilation and aortic stiffness by pulse wave velocity and augmentation index in 18 young healthy hookah smokers 21-39 years old, before and after ad lib 30-minute smoking/ vaping exposure sessions. To test for oxidative stress mediation, the investigators will determine if any acute impairment in endothelial function after e-hookah can be prevented by intravenous Vitamin C infusion, a potent anti-oxidant. Inflammatory and oxidant biomarkers, as well as smoking exposure biomarkers will be collected before and after the exposure sessions. The results of this proposal: (a) stand to fill in gaps in our mechanistic understanding of the comparative effect of traditional vs. e-hookah bowl on vascular and endothelial function; and (b) help inform policy decisions by the FDA about regulation of hookah products.

Enrollment: 19 patients

Sex: All

Ages: 21 to 39 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 21-39 years old hookah smokers: smoked hookah >12x in last 12 months
• no history of illicit drugs or marijuana
• no evidence of cardiopulmonary disease by history/ physical
• no diabetes: fasting blood glucose <100 mg/dl
• BP<140/90mmHg
• resting HR<100 bpm
• BMI<30kg•m2
• no prescription medication

Exclusion criteria

• exhaled CO>10 ppm (smoking non-abstinence)
• positive pregnancy test
• psychiatric illness

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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19 participants in 2 patient groups

Traditional Charcoal-Heated Hookah followed by Electronic Hookah

Experimental group

Description:

Participants were invited to smoke a 30-minute traditional charcoal-heated hookah-smoking session, followed by a 30-minute electronic hookah vaping session. To mitigate the impact of carryover effects, the two sessions were separated by a minimum of 7-days.

Treatment:

Other: Electronic hookah vaping

Other: Traditional hookah smoking

Electronic followed by Traditional Charcoal-Heated Hookah

Experimental group

Description:

Participants were invited to vape a 30-minute electronic hookah session, followed by a 30-minute traditional charcoal-heated hookah smoking session. To mitigate the impact of carryover effects, the two sessions were separated by a minimum of 7-days.

Treatment:

Other: Electronic hookah vaping

Other: Traditional hookah smoking