Effect of dulaglutide in promoting abstinence during smoking cessation: 12-month follow-up of a single-centre, randomised, double-blind, placebo-controlled, parallel group trial

Background

Smoking cessation is challenging, despite making use of established smoking cessation therapies. Preclinical studies and one clinical pilot study suggest the antidiabetic drug glucagon-like peptide-1 (GLP-1) analogue to modulate addictive behaviours and nicotine craving. Previously, we reported the short-term results of a randomised, double-blind, placebo-controlled trial. Herein we report long-term abstinence rates and weight developments after 24 and 52 weeks.

Methods

This single-centre, randomised, double-blind, placebo-controlled, parallel group trial was done at the University Hospital Basel in Switzerland. We randomly assigned (1:1) individuals with at least a moderate nicotine dependence willing to quit smoking to either a 12-week treatment with dulaglutide 1.5 mg or placebo subcutaneously once weekly in addition to standard of care smoking cessation therapy (varenicline 2 mg/day and behavioural counselling). After 12 weeks, dulaglutide or placebo injections were discontinued and the participants were followed up at week 24 and 52. The primary outcome of self-reported and biochemically confirmed point prevalence abstinence rate, and secondary outcome of secondary outcome of weight change were assessed at weeks 24 and 52. All participants who received one dose of the study drug were included in the intention to treat set and participants who received at least 10/12 doses of the study drug formed the per protocol set. The trial was registered at ClinicalTrials.gov, NCT03204396.

Findings

Of the 255 participants who were randomly assigned between June 22, 2017 and December 3, 2020, 63% (80/127) (dulaglutide group) and 65% (83/128) (placebo group) were abstinent after 12 weeks. These abstinence rates declined to 43% (54/127) and 41% (52/128), respectively, after 24 weeks and to 32% (41/127) and 32% (41/128), respectively, after 52 weeks. Post-cessation weight gain was prevented in the dulaglutide group (-1.0 kg, standard deviation [SD] 2.7) as opposed to the placebo group (+1.9 kg, SD 2.4) after 12 weeks. However, at week 24, increases in weight from baseline were observed in both groups (median, interquartile range [IQR]: dulaglutide: +1.5 kg, [-0.4, 4.1], placebo: +3.0 kg, [0.6, 4.6], baseline-adjusted difference in weight change -1.0 kg (97.5% CI [-2.16, 0.16])), and at week 52 the groups showed similar weight gain (median, IQR: dulaglutide: +2.8 kg [-0.4, 4.7], placebo: +3.1 kg [-0.4, 6.0], baseline-adjusted difference in weight change: -0.35 kg (95% CI [-1.72, 1.01])). In the follow-up period (week 12 to week 52) 51 (51%) and 48 (48%) treatment-unrelated adverse events were recorded in the dulaglutide and the placebo group, respectively. No treatment-related serious adverse events or deaths occurred.

Interpretation

Dulaglutide does not improve long-term smoking abstinence, but has potential to counteract weight gain after quitting. However, 3 months of treatment did not have a sustained beneficial effect on weight at 1 year. As post-cessation weight gain is highest in the first year after quitting smoking, future studies should consider a longer treatment duration with a GLP-1 analogue in abstinent individuals.

Funding

Swiss National Science Foundation, the Gottfried and Julia Bangerter-Rhyner Foundation, the Goldschmidt-Jacobson Foundation, the Hemmi-Foundation, the University of Basel, the Swiss Academy of Medical Sciences.

Smoking cessation after diagnosis of COPD is associated with lower all-cause and cause-specific mortality: a nationwide population-based cohort study of South Korean men

BACKGROUND

The most effective way to halt the advancement of COPD is smoking cessation. However, limited data are available on the question of whether quitting smoking within two years after COPD diagnosis reduces the risk of mortality. The goal of our research was to analyze the relationship between quitting smoking after COPD diagnosis and the risks of all-cause and cause-specific mortality, using the Korean National Health Insurance Service (NHIS) database.

METHODS

This study included 1,740 male COPD patients aged 40 years or more who had been newly diagnosed within the 2003-2014 time period and had smoked prior to their COPD diagnosis. The patients were categorized into two groups according to their smoking status after COPD diagnosis: (i) persistent smokers (ii) quitters (smoking cessation within two years of COPD diagnosis). Multivariate Cox proportional hazard regression was performed to determine the adjusted hazard ratio (HR) and 95% confidence interval (CI) for both all-cause and cause-specific mortality.

RESULTS

Among 1,740 patients (mean age, 64.6 years; mean follow-up duration, 7.6 years), 30.5% stopped smoking after COPD diagnosis. Quitters gained a 17% risk reduction in all-cause mortality (aHR, 0.83; 95% CI, 0.69-1.00) and a 44% risk reduction in cardiovascular mortality (aHR, 0.56; 95% CI, 0.33-0.95) compared with persistent smokers.

CONCLUSION

Our study found that patients who quit smoking within two years after COPD diagnosis had lower risks of all-cause and cardiovascular mortality relative to persistent smokers. These results can be used to encourage newly diagnosed COPD patients to stop smoking.

Longer-term use of electronic cigarettes when provided as a stop smoking aid: Systematic review with meta-analyses

Moderate certainty evidence supports use of nicotine electronic cigarettes to quit smoking combustible cigarettes. However, there is less certainty regarding how long people continue to use e-cigarettes after smoking cessation attempts. We set out to synthesise data on the proportion of people still using e-cigarettes or other study products at 6 months or longer in studies of e-cigarettes for smoking cessation. We updated Cochrane searches (November 2021). For the first time, we meta-analysed prevalence of continued e-cigarette use among individuals allocated to e-cigarette conditions, and among those individuals who had successfully quit smoking. We updated meta-analyses comparing proportions continuing product use among individuals allocated to use nicotine e-cigarettes and other treatments. We included 19 studies (n = 7787). The pooled prevalence of continued e-cigarette use at 6 months or longer was 54% (95% CI: 46% to 61%, I2 86%, N = 1482) in participants assigned to e-cigarette conditions. Of participants who had quit combustible cigarettes overall 70% were still using e-cigarettes at six months or longer (95% CI: 53% to 82%, I2 73%, N = 215). Heterogeneity in direction of effect precluded meta-analysis comparing long-term use of nicotine e-cigarettes with NRT. More people were using nicotine e-cigarettes at longest follow-up compared to non-nicotine e-cigarettes, but CIs included no difference (risk ratio 1.15, 95% CI: 0.94 to 1.41, n = 601). The levels of continued e-cigarette use observed may reflect the success of e-cigarettes as a quitting tool. Further research is needed to establish drivers of variation in and implications of continued use of e-cigarettes.

Efficacy of smoking cessation intervention delivered through mobile tele-counseling among smokers with tuberculosis in a Revised National Tuberculosis Control Program

BACKGROUND

India has high burden of tuberculosis and smokers. Prevalence of tuberculosis is three times higher in smokers than non-smokers. Active smoking causes severe disease, delay in seeking treatment, lost to treatment follow up, delayed sputum conversion and drug resistance. WHO advocates mobile phone technology to improve health outcomes (mHealth). We used mobile tele-counseling as a smoking cessation intervention in smokers with tuberculosis (TB) receiving treatment under tuberculosis control program.

AIM

To determine smoking quit rate at six months of TB treatment among smokers receiving mobile tele-counseling versus brief advice and to estimate smoking quit rates and relapse rates during the tele-counseling period.

METHODS

Open label randomized controlled trial. Newly detected pulmonary tuberculosis or pleural effusion patients received brief advice on smoking cessation as per The UNION's guiding framework. Subjects were then randomly allocated to intervention or control group. Intervention group was contacted telephonically at 2,3,4,5 and 6 months to assess smoking quit rates and provide continued smoking cessation advice.

RESULTS

Intervention group had 80 and 82 in the control group, mean (SD) age was 40.6(12.6), 43.5(12.7) p = 0.53. Quit rate at six months was 54 (67.5%) in intervention group versus 34 (42%) in control group; RR 1.60 (95% CI 1.19, 2.16) p = 0.001. Trend in smoking quit rates in intervention group was 81.3%, 61.3%, 55%, 73.8% at 2,3,4 and 5 months respectively. Smoking relapse rate was 43.1%, 53.1%, 20.5%,15.3% at 3,4,5 and 6 months respectively. 27.5%, 43.8% were abstinent for last three, two months.

CONCLUSIONS

Mobile tele-counseling is an effective strategy for smoking cessation among TB patients.

No changes in dietary intake after quitting smoking; a prospective study in Switzerland

BACKGROUND

After quitting smoking, quitters frequently increase their weight and change their dietary intake. Still, most studies on the topic are over 20 years old and focused on few dietary markers. We analysed the changes in weight and dietary intake after quitting smoking using a large panel of dietary markers.

METHODS

Prospective study including 5064 participants, 169 of whom (3.3%) quitted during a median follow-up of 5 years. Dietary intake was assessed using a food frequency questionnaire. Participants were excluded if they lacked dietary data or reported extreme total energy intakes (TEI) < 850 or > 4000 kcal/day.

RESULTS

Data from 128 participants (43.8% women, aged 56.0 ± 10.0 years) were used. After quitting smoking, mean weight increased 2.1 ± 0.7 kg; the majority (58%) of the participants gained over 1 kg, and only 7.1% were on a diet to reduce their weight. Total protein intake increased from (median [interquartile range]) 14.4 [12.9-16.4] to 15.1 [13.4-17.9] % of total energy intake (TEI), p = 0.008, while animal protein intake increased from 9.7 [8.0-12.1] to 10.8 [8.5-13.5] %TEI, p = 0.011. Fish intake increased from 27 [17-45] to 37 [19-55] g/day, p = 0.016 and dairy intake decreased from 177 [94-288] to 150 [77-243] g/day, p = 0.009. No other changes were found. Among the 68 (53%) participants who reported time since quitting, quitting for <=1 year led to a decreased consumption of fruits, while the opposite was found for participants who quit for longer than one year. No associations were found between weight or dietary changes and time since quitting.

CONCLUSIONS

People who quit smoking tend to gain weight, do not significantly change their dietary intake, and seem to make little effort to prevent weight gain. Systematic dietary support should be provided to all smokers wishing to quit.

Association of smoking cessation after atrial fibrillation diagnosis on the risk of cardiovascular disease: a cohort study of South Korean men

BACKGROUND

While smoking elevates the risk for cardiovascular disease (CVD) among atrial fibrillation (AF) patients, whether smoking cessation after AF diagnosis actually leads to reduced CVD risk is unclear. We aimed to determine the association of smoking cessation after AF diagnosis with subsequent CVD Risk among South Korean men.

METHODS

This retrospective cohort study included 2372 newly diagnosed AF male patients during 2003-2012 from the Korean National Health Insurance Service database. Self-reported smoking status within 2 years before and after diagnosis date were determined, after which the participants were divided into continual smokers, quitters (smokers who quit after AF diagnosis), sustained-ex smokers (those who quit prior to AF diagnosis), and never smokers. Participants were followed up from 2 years after AF diagnosis until 31 December 2015 for CVD. Cox proportional hazards regression was used to determine the adjusted hazard ratios (aHRs) and 95% confidence interval (CIs) for CVD according to the change in smoking habits before and after AF diagnosis.

RESULTS

The mean (standard deviation, minimum-maximum) age of the study subjects was 62.5 (8.6, 41-89) years. Among AF patients, quitters had 35% reduced risk (aHR 0.65, 95% CI 0.44-0.97) and never smokers had 32% reduced risk (aHR 0.68, 95% CI 0.52-0.90) for CVD compared to continual smokers (p for trend 0.020). Similarly, compared to continual smokers, quitters had 41% risk-reduction (aHR 0.59, 95% CI 0.35-0.99) and never smokers 34% risk-reduction (aHR 0.66, 95% CI 0.46-0.93) for total stroke (p for trend 0.047). Quitters had 50% reduction (aHR 0.50, 95% CI 0.27-0.94), sustained ex-smokers had 36% reduction (aHR 0.64, 95% CI 0.42-0.99), and never smokers had 39% reduction (aHR 0.61, 95% CI 0.41-0.91) in ischemic stroke risk (p for trend 0.047). The risk-reducing effect of quitting on CVD risk tended to be preserved regardless of aspirin or warfarin use.

CONCLUSIONS

Smoking cessation after AF diagnosis was associated with reduced CVD, total stroke, and ischemic stroke risk.

Similar softening across different racial and ethnic groups of smokers in California as smoking prevalence declined

Smoking prevalence differs among different racial/ethnic groups. Previous research found that as smoking prevalence declined in the U.S., remaining smokers made more quit attempts and smoked fewer cigarettes per day (CPD), indicating so-called softening. We examined California, a state with a highly diverse population, to assess whether there is differential softening among remaining smokers in different racial/ethnic groups. We used the California Tobacco Survey (1990-2008, N: 145,128). We ran logistic and linear regressions for smoking prevalence, CPD, quit attempts and time to first cigarette (30 min) as a function of race/ethnicity (non-Hispanic White, Hispanic, African American, Japanese, Chinese, Filipino, Korean, other Asian/Pacific Islander, American Indian/Alaska Native) controlling for other demographics. Overall prevalence fell from 21.1% in 1990 to 12.3% in 2008 (p < 0.01), showing similar declining trends across all racial/ethnic groups (p = 0.44), albeit from different baseline prevalence levels. In terms of softening indicators the proportion with at least one quit attempt in the past 12 months increased from 46.2% to 59.3%, a factor of 1.25 per decade (95%CI = 1.17, 1.34) in the adjusted model. CPD declined from 16.9 to 10.9, by -2.95 CPD per decade (95%CI = -3.24, -2.67) in the adjusted model. There were no significant changes in the time to first cigarette. Interactions of race/ethnicity and time show similar trends among all subgroups expect Hispanics, whose CPD remained stable rather than declining. Although from different baseline levels, tobacco control policies have benefitted all subgroups of California smokers, exhibiting similar softening as prevalence fell. Interventions are still needed to reduce the baseline differences.

[How does vaping products work]

To maximize the chances of replacing smoking with vaping, it is necessary to know the different types of existing devices, their characteristics and their most important settings as well as their influence on sensations. To support a user it is also important to understand the nature of the inhaled and exhaled vapor, as well as the possible mistakes that can lead to a less enjoyable experience. Highlighting e-liquids formulations and emissions can help understanding how a minimum of 95 % risk reduction compared to tobacco smoking is achieved and the influence of compounds on the user's experience. At last, a proper care, especially to refill the device and to change the resistance is the key to an effective use over time.

ADHD symptoms impact smoking outcomes and withdrawal in response to Varenicline treatment for smoking cessation

INTRODUCTION

Attention-Deficit/Hyperactivity Disorder (ADHD) is associated with nicotine dependence and difficulty quitting smoking. Few cessation trials specifically consider the impact of ADHD on treatment outcomes, including those testing established pharmacological therapies, such as varenicline.

METHODS

The current study focused on the impact of pretreatment ADHD inattention (IN) and hyperactivity-impulsivity (HI) symptoms on treatment outcome in a randomized controlled trial of varenicline [N=205, average age=34.13(10.07), average baseline cigarettes per day=14.71(7.06)]. Given that varenicline's putative therapeutic mechanism is attenuation of withdrawal severity during abstinence, we also tested changes in withdrawal as a mediator of treatment effects in high and low ADHD groups.

RESULTS

ADHD symptom severity in this sample was in the subclinical range. Cessation was associated with HI, but not IN, such that high HI individuals on varenicline reported the lowest smoking levels at the end of treatment across all groups (3.06cig/day for high HI vs 4.02cig/day for low HI). Individuals with high HI who received placebo had the highest smoking at the end of treatment (7.69cigs/day for high HI vs 5.56cig/day for low HI). Patterns continued at follow-up. Varenicline significantly reduced withdrawal for those with high HI, but not low HI. However, path models did not support an indirect effect of medication on reducing smoking via withdrawal in either group, suggesting that unmeasured variables are involved in varenicline's effect on reducing smoking.

CONCLUSIONS

These data add to a gap in the smoking cessation literature regarding the impact of ADHD symptoms on the efficacy and mechanisms of frontline pharmacological treatments.

Barriers to Quitting Smoking Among Substance Dependent Patients Predict Smoking Cessation Treatment Outcome

For smokers with substance use disorders (SUD), perceived barriers to quitting smoking include concerns unique to effects on sobriety as well as usual concerns. We expanded our Barriers to Quitting Smoking in Substance Abuse Treatment (BQS-SAT) scale, added importance ratings, validated it, and then used the importance scores to predict smoking treatment response in smokers with substance use disorders (SUD) undergoing smoking treatment in residential treatment programs in two studies (n=184 and 340). Both components (general barriers, weight concerns) were replicated with excellent internal consistency reliability. Construct validity was supported by significant correlations with pretreatment nicotine dependence, smoking variables, smoking self-efficacy, and expected effects of smoking. General barriers significantly predicted 1-month smoking abstinence, frequency and heaviness, and 3-month smoking frequency; weight concerns predicted 1-month smoking frequency. Implications involve addressing barriers with corrective information in smoking treatment for smokers with SUD.

Evaluating the association between menthol cigarette use and the likelihood of being a former versus current smoker

Menthol in cigarettes has been examined for its potential to affect smoking dependence, measured primarily as number of cigarettes smoked per day and time to first cigarette after waking; the ability to quit smoking constitutes an additional measure of dependence. Successful quitting among menthol compared to non-menthol cigarette smokers is difficult to determine from the literature, due in part to the various definitions of quitting used by researchers. Nevertheless, intervention and follow-up studies of smoking cessation treatments generally indicate no differences in quitting success among menthol compared to non-menthol smokers, while cross-sectional studies suggest some differences within race/ethnicity groups. The association between menthol cigarette use and likelihood of being a former versus current smoker was examined based on data from the National Health Interview Survey and Tobacco Use Supplement to the Current Population Survey. Analyses stratified by race/ethnicity and limited to smokers who had quit at least one year prior to survey participation provided inconsistent results with regard to menthol cigarette use and quitting, both within surveys (i.e., comparing race/ethnicity groups) and between surveys (i.e., same race/ethnicity group across surveys). Evidence suggesting the existence or direction of an association between menthol in cigarettes and quitting depended on the data source.

Gender differences in characteristics and outcomes of smokers diagnosed with psychosis participating in a smoking cessation intervention

While research has identified gender differences in characteristics and outcomes of smokers in the general population, no studies have examined this among smokers with psychosis. This study aimed to explore gender differences among 298 smokers with psychosis (schizophrenia, schizoaffective and bipolar affective disorder) participating in a smoking intervention study. Results revealed a general lack of gender differences on a range of variables for smokers with psychosis including reasons for smoking/quitting, readiness and motivation to quit, use of nicotine replacement therapy, and smoking outcomes including point prevalence or continuous abstinence, and there were no significant predictors of smoking reduction status according to gender at any of the follow-up time-points. The current study did find that female smokers with psychosis were significantly more likely than males to report that they smoked to prevent weight gain. Furthermore, the females reported significantly more reasons for quitting smoking and were more likely to be driven by extrinsic motivators to quit such as immediate reinforcement and social influence, compared to the male smokers with psychosis. Clinical implications include specifically focussing on weight issues and enhancing intrinsic motivation to quit smoking for female smokers with psychosis; and strengthening reasons for quitting among males with psychosis.

Estimating the decline in excess risk of chronic obstructive pulmonary disease following quitting smoking - a systematic review based on the negative exponential model

We quantified the decline in COPD risk following quitting using the negative exponential model, as previously carried out for other smoking-related diseases. We identified 14 blocks of RRs (from 11 studies) comparing current smokers, former smokers (by time quit) and never smokers, some studies providing sex-specific blocks. Corresponding pseudo-numbers of cases and controls/at risk formed the data for model-fitting. We estimated the half-life (H, time since quit when the excess risk becomes half that for a continuing smoker) for each block, except for one where no decline with quitting was evident, and H was not estimable. For the remaining 13 blocks, goodness-of-fit to the model was generally adequate, the combined estimate of H being 13.32 (95% CI 11.86-14.96) years. There was no heterogeneity in H, overall or by various studied sources. Sensitivity analyses allowing for reverse causation or different assumed times for the final quitting period little affected the results. The model summarizes quitting data well. The estimate of 13.32years is substantially larger than recent estimates of 4.40years for ischaemic heart disease and 4.78years for stroke, and also larger than the 9.93years for lung cancer. Heterogeneity was unimportant for COPD, unlike for the other three diseases.

Constructing a trial as a personal lifestyle change project: participants' experiences in a clinical study for nicotine vaccination

The purpose of this study was to gain insight into the experiences and dynamics of the involvement of research participants in a randomized clinical trial for nicotine vaccination. Participants received an experimental nicotine vaccine or a placebo, in addition to quit smoking medication and counseling. The longitudinal design of this qualitative study allowed us to follow people from their first visit to the trial location until the unblinding of their treatment with either verum or placebo vaccine. The empirical data consisted of 49 semi-structured, in-depth interviews, field notes and memos, and trial documents collected in the Netherlands between 2010 and 2012. Participants' expectations and experiences of the innovative nicotine vaccine were characterized by ambivalence: Although they complied with the research design, throughout the study they tinkered with discourses, objects, and activities to make them serve their individual goals. They made the concepts of nicotine vaccination and placebo treatment meaningful for quitting, reshaped the meaning of research tests and obligatory visits to serve their own personal goals, and introduced a new element into the trial by creating space to discuss problems that might endanger the quit attempt. In short, the participants constructed the clinical study for nicotine vaccination as their own personal lifestyle change project.

Estimating the decline in excess risk of cerebrovascular disease following quitting smoking--a systematic review based on the negative exponential model

We attempted to quantify the decline in stroke risk following quitting using the negative exponential model, with methodology previously employed for IHD. We identified 22 blocks of RRs (from 13 studies) comparing current smokers, former smokers (by time quit) and never smokers. Corresponding pseudo-numbers of cases and controls/at risk formed the data for model-fitting. We tried to estimate the half-life (H, time since quit when the excess risk becomes half that for a continuing smoker) for each block. The method failed to converge or produced very variable estimates of H in nine blocks with a current smoker RR <1.40. Rejecting these, and combining blocks by amount smoked in one study where problems arose in model-fitting, the final analyses used 11 blocks. Goodness-of-fit was adequate for each block, the combined estimate of H being 4.78(95%CI 2.17-10.50) years. However, considerable heterogeneity existed, unexplained by any factor studied, with the random-effects estimate 3.08(1.32-7.16). Sensitivity analyses allowing for reverse causation or differing assumed times for the final quitting period gave similar results. The estimates of H are similar for stroke and IHD, and the individual estimates similarly heterogeneous. Fitting the model is harder for stroke, due to its weaker association with smoking.