People who vape and smoke cigarettes are no more likely to drop the nicotine habit than those who just smoke, a new study suggests.

Researchers at The Ohio State University studied 705 tobacco users and found no differences in quit rates for “dual users” of both traditional and electronic cigarettes.

This research adds important information to the conversation as public health and medical professionals grapple with the role vaping might play in reducing cigarette smoking, said study senior author Mary Ellen Wewers, a professor emeritus of health behavior and health promotion, and a member of Ohio State’s Center of Excellence in Tobacco Regulatory Science.

Participants in the study were part of a larger group of about 1,200 rural and urban Ohioans whose habits are being followed by researchers. All of them are considered heavy tobacco users – those who smoke every day or at least some days every week.

The study appears in the journal Nicotine & Tobacco Research.

The researchers sat down with participants every six months for 18 months to ask them about tobacco use, interest in quitting and quit attempts they’d made. They also documented what type of tobacco products the participants used.

At the first check-in, six months into the study, the dual users were more likely to have stopped using tobacco, but that difference disappeared by the 1-year and 18-month interviews. By the end of the study, most dual users were back to smoking cigarettes exclusively.

“The initial difference we saw might be due to a higher interest in quitting among the dual users, but that higher quit rate vanished with time,” said lead author Laura Sweet, a graduate student in Ohio State’s College of Public Health.

“Tobacco is such a huge killer, and if these products help people quit, that could be really significant for public health. But in this study it looks like they don’t, and we need to know that as well,” Sweet said.

Though electronic products still deliver nicotine and much remains unknown about their long-term health effects,there’s general agreement that they are less harmful than cigarettes in adults.

“The hope would be that adult cigarette smokers are trying e-cigarettes because they want to stop cigarettes and are looking for alternatives to help them,” Wewers said, adding that she and others who work on tobacco prevention are concerned that younger people who vape will start there and transition to cigarettes down the road.

The researchers can’t be sure what factors contributed to their findings, but the results prompted Sweet to wonder if many adults who smoke and vape are doing so because vaping is more accepted in certain environments, rather than because vaping might help them drop nicotine altogether, she said.

Wewers, a member of the Cancer Control Research Program at Ohio State’s Comprehensive Cancer Center, said she wasn’t surprised to see a higher likelihood of quitting cigarettes at six months in the dual users, because that group expressed greater interest in quitting overall.

“It makes sense that during the first few months they may do better at quitting, but given that cigarette smoking is such a cyclical thing – people quit and resume all the time – it’s not surprising that they went back to smoking after a year,” she said.

Because this study didn’t assess light smokers or those who consider themselves “social” smokers, it’s hard to say what role vaping might play in quitting, Wewers said.