Study of e-cigarettes in British teenagers gives mixed signals

by Kate Kelland LONDON (Reuters) – A British study into smoking and e-cigarette use among British teenagers has produced mixed results, prompting scientists to warn against changing policy decisions or health advice public until the evidence becomes clearer. The study, published online Thursday in the British Medical Journal's peer-reviewed journal Tobacco Control, suggests there may be evidence that e-cigarettes could encourage British teenagers to try smoking tobacco. But the findings don't match underlying trends in smoking and have drawn criticism from outside experts. The results showed that among adolescents who, at the start of the survey, said they had never smoked cigarettes but had tried e-cigarettes, more than a third, or 34.4%, said a year later having tried cigarettes. This compares to just 9 percent of the group who had not tried e-cigarettes at the start of the survey. Yet the study's researchers, led by Mark Conner of the University of Leeds, urged caution in interpreting their findings, noting that although e-cigarette use has increased in Britain , smoking rates continued to decline. “While recognizing that a causal relationship may be plausible, we cannot confirm this based on our findings and observed trends over the same period in the UK,” they wrote. “Given the lack of clarity regarding the mechanism linking e-cigarettes and cigarette use, we must be careful in formulating policy recommendations based on our findings.” LOW-RISK ALTERNATIVE The global scientific community is divided on the issue of e-cigarettes and whether or not they are a useful public health tool as a nicotine replacement therapy. Many experts, including those at Public Health England, believe e-cigarettes, which contain nicotine but not tobacco, are a less risky alternative to smoking. But the U.S. surgeon general last year urged lawmakers to impose pricing and tax policies that would discourage their use. Robert West, a professor of health psychology at University College London, said Conner's team was right to caution that this latest study did not show a causal link between e-cigarette use and the start of smoking. “It seems unlikely that e-cigarette use by young people will cause them to smoke more, as smoking rates in this age group are now falling at least as fast as they were before e-cigarettes become popular,” West said. Linda Bauld, professor of health policy at the University of Stirling, said the study provided no evidence that e-cigarette use is causing young people to become smokers. “It just shows that some teens who try e-cigarettes might then try tobacco, and in both cases it might just be one time,” she said. “If e-cigarettes caused smoking, then the steady decline in youth smoking that we have seen in national surveys in recent years would be reversed. But that is not the case: youth smoking in the UK Uni is at an unprecedented level.” (Reporting by Kate Kelland; editing by David Holmes)