Quitting smoking - VESUVIUS

The clinical question

More and more people are taking up vaping. But are electronic cigarettes safe, harmful, or just better than smoking tobacco cigarettes? That’s what the Vascular Effects of Regular Cigarettes Versus Electronic Cigarette Use (VESUVIUS) study, led by Professor Jacob George and his colleagues at the University of Dundee, aimed to find out. The study was set up to measure short term effects of e-cigarettes on blood vessel function to get an idea if there are any obvious early benefits to swapping from tobacco to electronic cigarettes.

What did the study involve?

The study recruited 114 long-term cigarette smokers who had smoked at least 15 cigarettes per day for at least 2 years, and who did not have established cardiovascular disease. They were allocated to one of three groups for one month: 

• Switching to e-cigarettes with nicotine (37 people).
• Switching to e-cigarettes without nicotine (37 people).
• People who were unwilling to quit continued smoking tobacco cigarettes (40 people) in a parallel preference cohort.

The researchers checked blood vessel function at the beginning of the trial and after 1 month using a test called flow mediated dilation (FMD). FMD measures how wide a blood vessel can open when blood rushes through it. They also measured the stiffness of blood vessels. Both FMD and blood vessel stiffness provide a measure of blood vessel health and future risk of cardiovascular disease. 

A carbon monoxide breath test, which measures how much carbon monoxide – a gas present in cigarette smoke – is in the body was used to check if participants were abstaining from smoking tobacco cigarettes. 

What did the study show?

Within 1 month of switching, the groups who swapped to e-cigarettes showed an improvement in their blood vessel health compared with tobacco cigarette smokers. In both groups that had swapped to vaping, FMD increased so that within a month they were about halfway towards achieving the FMD of healthy non smokers. And it didn’t seem to matter if participants were vaping e-cigarettes with or without nicotine. Women seemed to benefit more than men.

Why is the study important?

Despite many people making the switch from tobacco cigarettes to vaping, we still don’t know enough about the biological and health effects of e-cigarettes. The VESUVIUS study showed that, at least in the short term, swapping from tobacco cigarettes to e-cigarettes improved blood vessel function.

Although these promising results show a clear early benefit in switching from tobacco cigarettes to e-cigarettes, the study doesn’t measure the long-term effects of switching to e-cigarette use. More research is needed into the long-term implications of vaping to find out whether this benefit would be sustained.

Professor Jacob George, Professor of Cardiovascular Medicine and Therapeutics at the University of Dundee and Chief Investigator of the trial, was clear that the study did not show that vaping is good for you. He observed at a Science Media Centre Briefing called to contextualise the study results.

“They should not be seen as harmless devices for non-smokers or young people to try. However, for chronic tobacco smokers there were significant improvements in vascular function within a month of switching from a tobacco cigarette to an e-cigarette.”

Study details

"Cardiovascular effects of switching from tobacco cigarettes to electronic cigarettes."
Award reference:  PG/15/64/31681
Principal Investigator: Professor Jacob George, University of Dundee

Publication details

George J, Hussain M, Vadiveloo T, et al. Cardiovascular Effects of Switching From Tobacco Cigarettes to Electronic Cigarettes. J Am Coll Cardiol. 2019;74(25):3112-3120.