A University of Pennsylvania study found that both nicotine-containing and nicotine-free e-cigarettes produced measurable changes in vascular function immediately after use, according to research that will be presented at the Radiological Society of North America's annual meeting.
The investigation, which included 31 healthy smokers and vapers aged 21 to 49 years, utilized quantitative magnetic resonance imaging (MRI) to examine vascular responses following three different inhalation challenges: tobacco cigarette smoke, nicotinized e-cigarette aerosol, and nonnicotinized e-cigarette aerosol.
The researchers found significant decreases in resting blood flow velocity in the superficial femoral artery after inhalation (P < .05). The effect was most pronounced with nicotine-containing e-cigarettes, followed by nicotine-free devices. Venous oxygen saturation decreased in vapers regardless of nicotine content (P = .01).
The study protocol measured multiple vascular parameters through sophisticated MRI techniques. The researchers applied thigh cuff occlusion to assess flow-mediated dilation and quantified femoral artery flow velocity and venous oxygen saturation. Additional measurements included aortic arch pulse wave velocity and cerebrovascular reactivity via superior sagittal sinus monitoring.
Comparison with nonusers revealed that smokers and vapers exhibited 37% greater neurovascular compliance (P < .005) and 42% lower flow-mediated dilation (P < .05) at baseline.
Lead researcher Marianne Nabbout, MD, a radiology resident at the University of Arkansas for Medical Sciences, noted that the findings suggested potential implications for long-term vascular health. “Ultimately, we are relying on science to help guide the regulation of such products in favor of public health,” Dr. Nabbout noted. “Refraining from smoking and vaping is always recommended,” she added.
The study remained double-blinded and ongoing at the time of presentation. The National Institutes of Health provided support for this research.
The investigation included a control group of 10 nonsmokers/nonvapers aged 21 to 33 years who underwent baseline scan protocols for comparison. Twenty-two participants completed all three visits, while eight completed one visit and one participant completed two visits.