Vaping added to counseling leads to higher smoking quit rates versus counseling alone
Adding electronic cigarette (e-cigarette) use to smoking cessation counseling more than doubles the percentage of those who successfully quit smoking at 12 weeks when compared with counseling alone.
In a clinical trial of 376 smokers enrolled at 17 sites in Canada, 21.9% who were given nicotine-containing e-cigarettes in addition to counseling had quit smoking compared with 17.3% given nonnicotine e-cigarettes plus counseling and 9.1% who received counseling alone, reported Mark J. Eisenberg, MD, MPH, from Jewish General Hospital and McGill University, Montreal.
According to Dr. Eisenberg, even with the use of pharmacologic or behavioral therapy, more than two thirds of those attempting to quit return to smoking within 1 year. “For this reason, many smokers have adopted the use of e-cigarettes to quit smoking,” he said. “Nevertheless, the efficacy and safety of e-cigarettes for smoking cessation remain poorly delineated.”
The trial included active smokers who smoked at least 10 cigarettes/day and were motivated to quit. They were randomized to nicotine e-cigarettes, nonnicotine e-cigarettes, or no e-cigarettes. All three groups received smoking cessation counseling.
The primary endpoint was self-reported smoking abstinence in the past week and biochemical validation using expired-air carbon monoxide levels of 10 parts/million or less at 12 weeks, reduced from 52 weeks because of e-cigarette manufacturing delays.
Participants’ mean age was 52 years and 53% were male. Mean duration of smoking was 35 years, and the mean number of cigarettes smoked per day was 21. About 91% had failed at previous attempts to quit smoking, and 80% had used pharmacologic or behavioral therapy.
At each follow-up time point (1, 2, 4, 8, and 12 weeks), smoking abstinence was greater among the participants randomized to e-cigarettes. Compared with counseling alone, the 12-week results showed that nicotine e-cigarette users were 2.4 times more likely to quit smoking (95% confidence interval [CI], 1.3-4.6) and nonnicotine e-cigarette users were 1.9 times more likely to quit (95% CI, 1.0-3.8).
Among those who continued to smoke at 12 weeks, those in the nicotine e-cigarette arm smoked a mean of 5.7 fewer cigarettes/day than those who received counseling alone (95% CI, -8.0 to -3.3). Those who were randomized to nonnicotine e-cigarettes smoked a mean of 3.6 fewer cigarettes/day (95% CI, -6.3 to -1.0).
Smoking abstinence was more likely at each follow-up in those who received e-cigarettes compared with counseling alone, and it was most likely in those who received nicotine e-cigarettes. At 12 weeks, the rates of smoking abstinence were 5% in the nicotine e-cigarette arm, 3% in the nonnicotine e-cigarette arm, and 1% in the counseling-alone arm.
Few serious adverse events occurred: 1 in the nicotine e-cigarette arm (exacerbation of chronic obstructive pulmonary disease), 5 in the nonnicotine e-cigarette arm (appendicitis, neoplastic cecal lesion, myocardial infection, chest pain, and epistaxis), and 2 in the counseling-alone arm (critical limb ischemia and urinary tract infection). None were related to the treatment received.
Longer term follow-up will determine if the benefit of e-cigarettes persists over time, said Dr. Eisenberg, who indicated that the research team will continue to collect data for 1 year, with the last follow-up to be completed in September 2020.
Nancy Rigotti, MD, Massachusetts General Hospital, Boston, commented that the study provides important evidence regarding e-cigarettes, which is their efficacy for smoking cessation. “There’s a contentious debate going on about the relative benefits and harms of e-cigarettes for public health,” she said. “And the case for public health benefits rests on their ability to help smokers quit. Unfortunately at this point, there’s only a small body of high-quality evidence to answer this question, and an answer is urgently needed, so this new randomized controlled trial is an important contribution. Because it’s a relatively unselected group of smokers, that adds to its potential generalizability.”
Mark J. Eisenberg, MD, MPH, reported nothing to disclose; Nancy Rigotti, MD disclosed Consultant Fees/Honoraria Achieve Life Sciences, Pfizer.