Long-term smokers who switched to vaping were halfway towards achieving the vascular health of a non-smoker within a month, a study has found. Researchers from the University of Dundee, UK, said they discovered a “clear early benefit” in switching from smoking to vaping, in the largest clinical trial to date.
Those who ditched cigarettes and vaped instead saw their blood vessel function increase by around 1.5 percentage points within four weeks compared with those who continued smoking.
The researchers said they didn’t know whether this benefit would be sustained, with more research needed into the long-term implications of vaping. They also warned that vaping isn’t safe, merely “less harmful” than smoking.
But they said that if this improvement were sustained into the long-term, those who switched would have at least a 13 per cent reduced risk of cardiovascular events, such as heart attacks.
The study recruited 114 adults in the UK who had smoked at least 15 cigarettes a day for at least two years and were free from established cardiovascular disease.
Forty continued smoking tobacco cigarettes, 37 switched to e-cigarettes with nicotine and 37 switched to e-cigarettes without.
The researchers measured shifts in blood vessel function – the earliest detectable change to cardiovascular health – through a test known as flow mediated dilation (FMD) that assesses how far a blood vessel opens. They used another test to measure the vessels’ stiffness.
Overall, the groups who switched to e-cigarettes experienced a 1.49 percentage point improvement in their vascular function compared with those who continued smoking.
Separate research has shown that for every 1 percentage point improvement in vascular health, 13 per cent fewer cardiovascular events occur over the long-term.
A healthy non-smoker can expect an average FMD score of 7.7 per cent, the authors said. Chronic smokers who switched to vaping with nicotine saw their FMD increase by about a fifth from 5.5 per cent to 6.7 per cent at the end of the month. This means that, within a month, the new vapers were around halfway towards achieving the FMD of a healthy non-smoker.
Journal reference: Journal of the American College of Cardiology, DOI: 10.1016/j.jacc.2019.09.067