The time-varying effect of alcohol use on cigarette smoking relapse risk

A dynamical model of drinking and smoking with optimal control analysis

The intake of alcohol is dangerous, and the smoking of tobacco is savage, but it is life-threatening to practice both smoking and drinking. According to the World Health Organisation, the world loses about 8.5 million people each year as a result of smoking tobacco and drinking alcohol. To study this, we present a mathematical model that investigates the co-dynamics of alcohol drinking and tobacco smoking, as well as some control strategies. In contrast, many studies focus solely on the dynamics of alcohol consumption or tobacco smoking. Also, these studies assume that an individual who may recover from both alcohol drinking and tobacco smoking may relapse. We determined the basic reproductive number by employing the next-generation matrix approach. We conducted local and global stability analyses for the drinking, smoking-free, and endemic states. We then conducted extensive research into secondary infections related to smoking and drinking. We then performed numerical simulations and analysis using the parameter values from the literature. The study further examined the influence of some key parameters on secondary co-dependence infections, which occur when one infected individual enters the population and recovers from both over time. For example, in this study, it was shown that the contact rates a1 and a2 have a direct relationship to the spread of drinking and smoking. In contrast, recovery rates δ1, δ2 showed an inverse relationship. In addition, we conducted an optimal control analysis by suggesting the following: drinking prevention efforts, smoking prevention efforts, recovery efforts on the co-dependence of drinking and smoking, recovery efforts on drinking, and recovery efforts on smoking. The simulations indicated that using these controls can help reduce the number of smokers and drinkers within eight weeks.

Smoking, vaping and drinking: A qualitative analysis of Aotearoa New Zealand young adults who tried e-cigarettes to stop smoking tobacco

BACKGROUND AND AIM

Social practices such as smoking-drinking co-use often go 'hand-in-hand', linked by the coordination of materials, skills and meanings. However, the experience of using e-cigarettes while drinking among people who smoke (and drink) remains underexplored. We used social practice theory to show how smoking, vaping and drinking intersect and to explain how vaping created two new social practices among people who tried e-cigarettes to stop smoking: 'vaping-drinking' co-use and 'smoking-vaping-drinking' poly-use.

METHODS

We conducted five in-depth interviews over 18-24 weeks during 2018-19, with each of nine Aotearoa New Zealand young adults aged 20-29 years. Participants smoked daily, did not regularly use e-cigarettes at entry and wished to try vaping to stop smoking. We analysed participants' reports of smoking or vaping while drinking using thematic analysis.

RESULTS

Individual participants reported both co-use and poly-use occasions throughout the study. Vaping-drinking co-use arose from practice 'replacement' processes, where vaping fully substituted smoking. Smoking-vaping-drinking poly-use arose from 'adjacency' processes where vaping complemented smoking. Participants used both processes flexibly over time, which required new skills in material, temporal, pleasure and social coordination to try to recreate valued meanings of comfort, security and communality associated with well-established smoking-drinking practices. Unsuccessful coordination attempts maintained smoking-drinking co-use.

CONCLUSION

Among Aotearoa New Zealand young adult smokers who want to use vaping to stop smoking, drinking occasions may help to maintain existing smoking-drinking practices and facilitate the development of vaping-drinking co-use and smoking-vaping-drinking poly-use practices, potentially prolonging individuals' exposure to smoking.

Time-Varying Determinants of Changes in E-Cigarette Relative Harm Perception Among US Young Adults

BACKGROUND

Current e-cigarette use has increased among young adults in the USA despite a consistent decrease in perceiving e-cigarettes as less harmful than cigarettes over time. This study examined time-varying predictors associated with the changes in e-cigarette relative harm perception over time among US young adults.

METHODS

Data were from the 2013-2018 Population Assessment of Tobacco and Health (PATH) Study for young adults (18-24 years). A time-varying effect model (TVEM) was applied to examine the association between the relative harm perception change and the associated time-varying predictors.

RESULTS

Of the 8427 young adults, the prevalence of those who perceived e-cigarettes as less harmful than cigarettes decreased from 50.3% in Wave 1 (2013-2014) to 27.7% in Wave 4 (2016-2018). Young adults who were male were more likely to perceive e-cigarettes as less harmful than cigarettes over time (OR = 1.58; 95%CI, 1.53-1.64). In addition, the changes in e-cigarette relative harm perception were less noticeable among those with advanced degrees, who had non-combustible smoke-free home rules, who held negative tobacco-related attitudes, and those who were current e-cigarette users or ever used alcohol (all p values < 0.05).

CONCLUSIONS

A decline was observed in US young adults who perceived e-cigarettes as less harmful than cigarettes from the PATH Study across four waves (2013-2018). The study findings underscore the importance of risk communication that focuses on harm perception profiles and the need for appropriate interventions to balance the considerations of e-cigarette use among young adults.

Does alcohol consumption elevate smoking relapse risk of people who used to smoke? Differences by duration of smoking abstinence

BACKGROUND

Past research indicates dual users of tobacco and alcohol find it harder to quit smoking and may be more likely to relapse. This study investigated whether post-quit alcohol use predicted smoking relapse among ex-smokers, and whether this relationship varied by length of smoking abstinence.

METHOD

The study included 1064 ex-smokers (18+ years) from Canada (n = 340), US (n = 314), England (n = 261), and Australia (n = 149) who participated in the 2018 and 2020 International Tobacco Control Four Country Smoking and Vaping Survey, and we conducted analyses using multivariable logistic regression. We assessed alcohol consumption in 2018 using AUDIT-C and coded as never/low, moderate or heavy level and used alcohol consumption to predict smoking status in 2020.

RESULTS

Overall 26 % and 21 % of ex-smokers consumed alcohol at a moderate and heavy level, respectively. Compared to never/low alcohol consumption, risk of smoking relapse among those who consumed alcohol at a moderate level was significantly lower within the first year of abstinence (OR = 0.34, 95 % CI = 0.14-0.81, p = 0.015) but higher thereafter (OR = 2.44, 95 % CI = 1.13-5.23, p = 0.023). The pattern of results was similar for those who consumed alcohol at a heavy level.

CONCLUSIONS

Overall, baseline alcohol consumption of ex-smokers did not predict their smoking relapse risk. As expected, risk differed by smoking abstinence duration. However, the pattern was unexpected among the short-term quitters as the subgroup who drank moderately/heavily had lower relapse risk than their counterparts who never drink or at low level, underscoring the need to replicate this unexpected finding.

Time-Varying Effect Models for Examining Age-Dynamic Associations in Gerontological Research

OBJECTIVES

Dynamic processes unfolding over later adulthood are of prime interest to gerontological researchers. Time-varying effect modeling (TVEM) accommodates dynamic change trajectories, but its use in gerontological research is limited. We introduce and demonstrate TVEM with an empirical example based on the National Health and Aging Trends Study (NHATS).

METHODS

We examined (a) age-varying prevalence of past month elevated symptoms of depression and anxiety and (b) age-varying associations between older adults' elevated symptoms of depression and anxiety and needing help with basic activities of daily living and educational attainment.

RESULTS

The proportion of participants reporting elevated symptoms of depression and anxiety in the past month increased gradually from 23-29% across the ages 70-92. Individuals needing help with ADLs had higher odds of reporting elevated symptoms of depression and anxiety, however the association was strongest for those in their 60s versus 80s. Across all ages, adults with lower education levels had higher odds of reporting elevated symptoms of depression and anxiety, an association that also varied by age.

CONCLUSION

We demonstrated TVEM's value for studying dynamic associations that vary across chronological age. With the recent availability of free, user-friendly software for implementing TVEM, gerontological researchers have a new tool for exploring complex change processes that characterize older adults' development.

Changes in harm perception of ENDS and their predictors among US adolescents: findings from the population assessment of tobacco and health (PATH) study, 2013-2018

Electronic nicotine delivery systems (ENDS) use has dramatically increased in the US. This study aimed to characterize changes in ENDS harm perception over time and associated predictors among US adolescents. Data from the 2013-2018 Population Assessment of Tobacco and Health Study (PATH) for adolescents (12-17 years) were utilized. Trend analyses were employed to delineate changes in comparative and absolute ENDS harm perception over a four-year interval. We applied a time-varying effect model (TVEM) to examine the associations between the changes in harm perception and associated predictors. The results suggest that perception of ENDS as less harmful than cigarettes significantly decreased from 54.3% at Wave 1 (2013) to 30.4% at Wave 4 (2018) (P < 0.001). Perception of ENDS as no or little harm decreased from 35.9% at Wave 1 to 16.9% at Wave 4 (P < 0.001). These changes in harm perception were less robust among males, adolescents who did not have positive tobacco-related attitudes, and those with smoke-free home rules (P's < 0.05). Additionally, having ever used ENDS or alcohol were more likely to be associated with reduced ENDS-related harm perception over time (P's < 0.05). Our results show that while ENDS-related harm perception have generally increased, this does not appear to be equally experienced across all adolescents, potentially highlighting the importance of at-risk groups and targets for intervention. This study can help identify individuals at risk of ENDS initiation because of their favorable ENDS harm perception profile, as well as guide the development of ENDS risk communication interventions for adolescents.

Combined varenicline and naltrexone attenuates alcohol cue-elicited activation in heavy drinking smokers

BACKGROUND

There is a strong bidirectional relationship between the use of alcohol and cigarettes which results in various challenges for treating those who co-use both substances. While varenicline and naltrexone each have FDA-approval for nicotine and alcohol use disorder, respectively, there is evidence that their clinical benefit may extend across the two disorders. Critically, the effect of combined varenicline and naltrexone on neural reactivity to alcohol cues among heavy drinking smokers has not yet been studied. Probing the effect of the combination therapy on alcohol cue-reactivity may give insight to the mechanisms underlying its efficacy.

METHODS

Forty-seven heavy drinking smokers enrolled in two medication studies were randomized to receive varenicline alone (n = 11), varenicline plus naltrexone (n = 11), or placebo (n = 25). Participants completed an fMRI alcohol cue-reactivity task and rated their in-scanner alcohol craving. Whole-brain analyses examined the effect of medication on alcohol cue-elicited neural response.

RESULTS

Varenicline plus naltrexone attenuated alcohol cue-elicited activation in mesolimbic regions relative to varenicline alone and to placebo (Z > 2.3, p < 0.05). The combination varenicline and naltrexone group also endorsed lower in-scanner alcohol craving relative to varenicline alone group (p = 0.04).

CONCLUSIONS

These findings provide evidence for the benefit of combined therapy of varenicline and naltrexone over varenicline alone for the attenuation of alcohol cue-elicited neural activation. This study provides a preliminary proof-of-mechanism for this combination pharmacotherapy and suggests that naltrexone may be driving the reductions in cue-elicited alcohol craving in the brain. Further clinical studies using the combined therapy to treat heavy drinking smokers are warranted.

Experiences With Smoking Cessation Attempts and Prior Use of Cessation Aids in Smokers With HIV: Findings From a Focus Group Study Conducted in Durham, North Carolina

Cigarette smoking remains disproportionately prevalent and is increasingly a cause of death and disability among people with HIV (PWH). Many PWH are interested in quitting, but interest in and uptake of first-line smoking cessation pharmacotherapies are varied in this population. To provide current data regarding experiences with and perceptions of smoking cessation and cessation aids among PWH living in Durham, North Carolina, the authors conducted five focus group interviews (total n = 24; 96% African American) using semistructured interviews. Interviews were recorded, transcribed, coded, and thematically analyzed. Major themes included ambivalence and/or lack of interest in cessation; presence of cessation barriers; perceived perceptions of ineffectiveness of cessation aids; perceived medication side effects; and conflation of the harms resulting from use of tobacco products and nicotine replacement therapy. Innovative and effective interventions must account for the aforementioned multiple barriers to cessation as well as prior experiences with and misperceptions regarding cessation aids.