Smokers with chronic illnesses and diseases, particularly conditions linked to cigarette use, are more likely to start using e-cigs than healthy smokers, according to a recent survey.

The study, the first to investigate national prevalence and e-cig use among United States adults with medical conditions, found that smokers with chronic obstructive pulmonary disease, asthma or cardiovascular diseases had a higher chance of vaping than smokers and former smokers who haven’t suffered from these conditions.

Gina R. Kruse, MD of Massachusetts General Hospital, speculated that cigarette smokers that are suffering with diseases due to smoking are vaping to help them quit traditional tobacco.

A landmark study found that e-cigs substantially improve a smoker’s health, suggesting smokers who ditch cigarettes for e-cigs are making the right decision.

She added that it is impossible to know for sure why sick smokers are trying e-cigs.

“Smokers with comorbidities might be trying them and finding them not very helpful, or e-cigarettes may be helping people quit so they don’t need these products anymore,” she said. “That would be very hopeful, but we have no way of knowing if this is the case.”

Kruse failed to back e-cigs as a method of smoking cessation, but recommended “evidence-based therapies” should be used instead.

However, it seems Kruse is oblivious to the fact that e-cigs have helped thousands of UK smokers quit.

It has been reported that vaping doubles a smoker’s chances of quitting.