Study author Professor Guodong Liu from Penn State College of Medicine, said: 'No doubt about it, e-cigarettes are addictive, but not at the same level as traditional cigarettes'. The new study, published in BMJ medical journal, stands in contrast to previous studies suggesting that using e-cigarettes actually make it harder to quit.
According to the Centers for Disease Control and Prevention, cigarette smoking is still the leading cause of preventable death in the U.S. The agency says tobacco kills more than 480,000 people every year.
It showed that 49.3% of recent quitters had tried e-cigarettes, and that out of all smokers past and present, between 11.5% and 19% were current e-cigarette users.
To examine the effects of e-cigs use on quitting smoking, Zhu and his colleagues collected data from the US Census CPS-TUS. USA health officials have continued to promote abstinence to the public rather than encourage smokers to switch to less harmful products: online fact sheets published by CDC, FDA, and the National Cancer Institute list multiple health risks associated with smokeless tobacco, but give no indication it is less harmful than cigarettes.
They found that smokers who had used e-cigarettes within the past year were more likely to have attempted to quit than those who had not, with a 65% attempt rate compared with 38% in those who had never used them.
The report, which surveyed 161,054 people in the USA across nearly 15 years, also found that substantially more people in the States are using e-cigarettes, and that this was linked to a "statistically significant increase in the smoking cessation rate at the population level".
Zhu added that a national tobacco control campaign that began airing in 2012 probably also helped boost quit rates. Most devices heat a liquid nicotine solution into vapour and were promoted to smokers as a less risky alternative since they don't contain all the chemicals, tar or odour of regular cigarettes.
"They may do better with e-cigarettes because they may already be motivated to quit", he said.
The AHA said it is reasonable for physicians to support a patient's use of an e-cigarette to stop smoking if they have failed approved therapies and would like to try this approach.
Dr Bhatnagar said: 'We just don't know if moving to e-cigarettes is good enough to reduce the harm'.
Other study limitations included not addressing the long-term effects of e-cigs or investigating if the use of e-cigs leads people to start smoking. Food and Drug Administration finalized rules to regulate e-cigarettes. It's based on the largest representative sample of smokers and e-cigarette users available.