La vingtième conférence SRNT 2014 (Society for Research on Nicotine and Tobacco) s’est tenue à Seattle (USA). Voici les résumés (en anglais) de six recherches que nous avons trouvées particulièrement remarquables, en attendant leur - éventuelle - confirmation dans les revues scientifiques.
IS CYTISINE AT LEAST AS EFFECTIVE AS NICOTINE REPLACEMENT THERAPY FOR SMOKING CESSATION? FINDINGS FROM A NON-INFERIORITY TRIAL
N. Walker & al.
Cytisine is an alkaloid, found in plants such as Golden Rain and New Zealand Kowhai that partially blocks the effects of nicotine on the brain. Cytisine has been used for smoking cessation in several European countries since the 1960s, is inexpensive, and has few known side effects.
Placebo controlled trials non-inferiority was proven, as was superiority at all time points (one month continuous abstinence 40% cytisine vs 31% NRT; Relative risk = 1.30, 95% CI 1.12-1.51, p=0.004; Absolute risk difference = 9.3, 95% CI 4.2-14.5). Self-reported adverse events were more common in the intervention group (Incidence rate ratio=1.67, 95% CI 1.38-2.01, p<0.001), but were generally non-serious and self-limiting.
Conclusion: Cytisine combined with behavioural support is an effective cessation product, which has been shown to be superior to NRT plus behavioural support for smoking cessation, although adverse events are more common.
WHEN PLACEBO PATCHES WORK BETTER THAN ACTIVE PATCHES:
AN RCT TESTING THE QUIT ATTEMPT THEORY FOR SMOKING CESSATION
Shu-Hong Zhu & al.
Efforts to help smokers quit smoking generally emphasize relapse prevention, because most smokers relapse soon after making a quit attempt. This study tests a theory that places the primary emphasis on motivating smokers to make a quit attempt. It was hypothesized that sending smokers placebo patches by express mail would lead more to quit smoking than asking smokers to obtain active patches from a pharmacy, because timely access to a placebo would induce a larger proportion of them to make a quit attempt. A total of 4200 smokers who called the California Smokers’ Helpline were randomly assigned to 3 groups:
- Group 1 were to obtain nicotine patches by themselves,
- Group 3 were sent active patches directly from the Helpline by express mail, and
- Group 2 were sent placebo patches from the Helpline by express mail.
We hypothesized that the quit rates would be ordered as follows: Group 3 > Group 2 > Group 1. Assignment to Groups 2 and 3 was double blind, while assignment to no patches sent (Group 1) vs. patches sent (Groups 2 and 3) was not blind. Participants were followed for 7 months. The primary outcome was 6-month prolonged abstinence at 7 months.
By 7 months, 73,0% in Group 3 and 71,3% in Group 2 had used the patches sent from the Helpline, while only 30,1% of Group 1 used patches which they obtained themselves. Quit attempt rates were not different between Groups 3 and 2, and both were higher than for Group 1. The survival rate of those quit attempts over the 6-month period was not different between Groups 2 and 1, and both were lower than Group 3. The total 6-month prolonged abstinence rates were ordered as hypothesized: 3 > 2 > 1; the rates were 10.6%, 8.4%, and 5.8% for Group 3, 2, and 1, respectively, in an intent-to-treat analysis. All a priori hypothesized paired comparisons (3 vs. 1, 2 vs. 1) were statistically significant.
This is the first study to show a large effect for placebo NRT. This effect was achieved mainly by stimulating quit attempts, and this effect was so powerful that it outperformed the usual-care practice of sending smokers to obtain active NRT from a pharmacy for themselves. These results can be applied to public health campaigns to increase population cessation.
FACTORS THAT PREVENT ELECTRONIC CIGARETTE INITIATION IN ADOLESCENT AND YOUNG ADULT SMOKERS AND NON-SMOKERS
Camenga & al.
There is growing concern that electronic (e-) cigarette use is increasing in adolescents and young adults. The objective of this study is to examine the factors that prevent e-cigarette initiation among adolescents and young adult smokers and non-smokers. Eighteen focus groups were conducted in 2012-2013 in 2 colleges (n=59 students,), 2 high schools (n=52) and 2 middle schools (n=16) in New Haven County, CT. College and high school groups were stratified by gender and cigarette smoking status and middle school groups by gender only. A standard focus group guide was used to ask participants about their knowledge of electronic cigarettes reasons for use and non-use. Group discussions were recorded, transcribed, and examined using thematic analysis.
College and high school smokers were deterred by the high cost of e-cigarettes. They preferred the known satisfaction of a traditional cigarette to the “unknown feeling” of an e-cigarette. College smokers were hesitant to try e- cigarettes due to unknown health risks, and lack of scientific evidence supporting the products’ safety. College and high school non-smokers equated e-cigarettes to traditional cigarettes, and anti-tobacco sentiments shape their desire not to use e-cigarettes. They described the potential of adverse health effects/addiction as factors that prevent initiation, and believed that e-cigarettes are for “smokers only.” Both high school and middle school students described parental disapproval as a factor that prevents initiation, and high school students also described friend disapproval. All groups described lack of “coolness” as a factor that prevents initiation. Cost and unknown health risks prevent the initiation of e-cigarettes among college and high school smokers. Negative perceptions about traditional cigarettes shape non-smokers beliefs about e-cigarettes. High school and middle school students additionally describe parental disapproval as a reason not to initiate electronic cigarettes. Thematic analysis is ongoing. These formative qualitative data suggest that smokers and non-smokers identify distinct factors that prevent initiation of electronic cigarettes.
PHYSICIAN USE OF E-CIGARETTES AS CESSATION DEVICES
The University of North Carolina Tobacco Prevention and Evaluation Program (TPEP) conducted a survey of North Carolina (NC) physicians to assess physician awareness, knowledge, and behavior related to tobacco use cessation treatment, including the North Carolina Quitline. As part of the survey, physicians involved in direct patient care were asked about their knowledge regarding Food and Drug Administration (FDA) approval of electronic cigarettes (e-cigarettes), how often their patients who use tobacco inquire about e-cigarettes, their perception of e-cigarettes as a cessation product or harm reduction, and whether they recommended e-cigarettes to their patients. A direct marking company with access to the American Medical Association (AMA) mailing list distributed the survey through e-mail to a random sample of 787 NC Family Medicine, Internal Medicine, General Surgery, OB Gyn, and Psychiatry physicians. From this e-mail, 14 addresses were invalid or returned, 413 were opened, and 128 responded.
Respondents reported being asked (48.4% responded frequently or sometimes being asked) about e-cigarettes by patients that use tobacco, and 67.2% believed e-cigarettes were helpful in treating tobacco dependence. Almost two-thirds (64.8%) reported they believed that e-cigarettes lowered the risk of cancer compared to regular cigarettes. Over one third (35.2%) of respondents reported recommending the use of e-cigarettes to patients trying to quit. Thirteen percent of participants believed (incorrectly) that e-cigarettes were approved by the FDA as a tobacco cessation treatment. Analyses differentiated physicians and specialties who believed e-cigarettes were helpful compared to those that did not, as well as those that recommended them to patients for cessation. E-cigarettes appear to play a substantial role in clinical tobacco dependence treatment even though they are not approved or recommended by the FDA. This increasing utilization of e-cigarettes by the patient community has profound implications for tobacco use treatment and potential FDA regulation. We will discuss recommendations and potential guidelines for physician-patient counseling about e-cigarettes.
REAL-WORLD EFFECTIVENESS OF E-CIGARETTES:
A POPULATION STUDY
Objective: This study aimed to assess, using an established methodology, the effectiveness of e-cigarettes compared with nicotine replacement therapy (NRT) bought over-the-counter and with unaided quitting in the general population.
Methods: A large survey of a representative sample of the English population. The study included 5726 adults who had smoked within the previous 12 months and made at least one quit attempt during that period with either an e-cigarette only (n=391), NRT bought over-the-counter only (n=2031) or no aid in their most recent quit attempt (n=3304). The primary outcome measure was self-reported abstinence up to the time of the survey, adjusted for key potential confounders including nicotine dependence.
Results: E-cigarette users were more likely still to be abstinent than either those who used NRT bought over-the-counter (OR=2,23, 95% CI=1,67- 2,97, 19,9% vs. 10,0%) or no aid (OR=1,40, 95% CI=1,07-1,82, 19,9% vs. 15,1%). The adjusted odds of non-smoking in users of e-cigarettes were 1,66 (95% CI=1,17-2,36) times higher compared with users of NRT bought over-the-counter and 1,60 (95% CI=1,15-2,23) times higher compared with those using no aid.
Conclusion: Among smokers stopping without professional support, those who use e-cigarettes appear more likely to be able to remain abstinent than those who use a licensed NRT product bought over-the-counter or no aid to cessation. This difference persists after adjusting for a wide range of smoker characteristics such as nicotine dependence.
IS SMOKING CESSATION ASSOCIATED
WITH THE SAME METABOLIC RISK IN MEN AND WOMEN?
Le Boudec & al.
BACKGROUND: Smoking cessation has been shown to increase the short-term risk of type 2 diabetes (DM), with differences between men and women. The aim of the study was to assess the association between smoking cessation and the incidence of DM and impaired fasting glucose (IFG) in a European population and to test if there was an interaction for sex in this association.
METHOD: Data from 4,974 participants from the CoLaus study in Lausanne, Switzerland, aged 35-75 at baseline and followed for 5 years were used. Participants were classified as smokers, recent quitters (quit for =5 years), long-term quitters (quit for >5 years), and non smokers at baseline, based on self-report. Altered glycemia at follow up was defined as either IFG (fasting serum glucose (FSG) 5,6-6,99 mmol/l and no treatment for DM) or DM (FSG =7,0 mmol/l and/or treatment).
We assessed the association between smoking status and incidence of altered glycemia using logistic regression with adjustment for age, education, physical activity, alcohol intake, hypercholesterolemia, hypertension, body-mass index, and waist circumference at baseline.
RESULTS: There were 3,166 participants (63% women) with normal baseline FSG with 846 (26.7%) smokers, 207 (6.5%) recent quitters, 743 (23.5%) long-term quitters, and 1,370 (43.3%) non smokers. During follow-up 1,358 participants (42.6%) developed an altered glycemia: 1311 (41.1%) IFG and 47 (1.5%) DM. In women, former and non-smokers tended to have increased odds of altered glycemia compared with smokers with ORs of 1.30 [95% confidence interval 0.83-2.04] for recent quitters, 1.03 [0.77-1.37] for long-term quitters, 1.10 [0.86-1.42] for never smokers. In men we observed an inverse relationship with ORs of respectively 0.91 [0.57-1.45], 0.78 [0.56-1.10] and 0.92 [0.68-1.24]. There was a significant interaction for sex (p=0.003).
CONCLUSION: We found no significant association between smoking cessation and the incidence of IFG or DM in our population. However, there was an interaction for sex; the risk of developing altered glycemia after smoking cessation tended to increase in women and to decrease in men.