Comparative effectiveness of post-discharge interventions for hospitalized smokers: study protocol for a randomized controlled trial

ABSTRACT: BACKGROUND: A hospital admission offers smokers an opportunity to quit. Smoking cessation counseling provided in the hospital is effective, but only if it continues for more than one month after discharge. Providing smoking cessation medication at discharge may add benefit to counseling. A major barrier to translating this research into clinical practice is sustaining treatment during the transition to outpatient care. An evidence-based, practical, cost-effective model that facilitates the continuation of tobacco treatment after discharge is needed. This paper describes the design of a comparative effectiveness trial testing a hospital-initiated intervention against standard care. Methods/design: A 2-arm randomized controlled trial compares the effectiveness of standard post-discharge care with a multi-component smoking cessation intervention provided for 3 months after discharge. Current smokers admitted to Massachusetts General Hospital who receive bedside smoking cessation counseling, intend to quit after discharge and are willing to consider smoking cessation medication are eligible. Study participants are recruited following the hospital counseling visit and randomly assigned to receive Standard Care or Extended Care after hospital discharge. Standard Care includes a recommendation for a smoking cessation medication and information about community resources. Extended Care includes up to 3 months of free FDA-approved smoking cessation medication and 5 proactive computerized telephone calls that use interactive voice response technology to provide tailored motivational messages, offer additional live telephone counseling calls from a smoking cessation counselor, and facilitate medication refills. Outcomes are assessed at 1, 3, and 6 months after hospital discharge. The primary outcomes are self-reported and validated 7-day point prevalence tobacco abstinence at 6 months. Other outcomes include short-term and sustained smoking cessation, post-discharge utilization of smoking cessation treatment, hospital readmissions and emergency room visits, and program cost per quit. DISCUSSION: This study tests a potentially disseminable smoking intervention model for hospitalized smokers. If effective and widely adopted, it could help to reduce population smoking rates and thereby reduce tobacco-related mortality, morbidity, and health care costs.     

The Cessation in Pregnancy Incentives Trial (CPIT): study protocol for a randomized controlled trial

ABSTRACT: BACKGROUND: Seventy percent of women in Scotland have at least one baby, making pregnancy an opportunity to help most young women quit smoking before their own health is irreparably compromised. By quitting during pregnancy their infants will be protected from miscarriage and still birth as well as low birth weight, asthma, attention deficit disorder and adult cardiovascular disease. In the UK, the NICE guidelines: 'How to stop smoking in pregnancy and following childbirth' (June 2010) highlighted that little evidence exists in the literature to confirm the efficacy of financial incentives to help pregnant smokers to quit. Its first research recommendation was to determine: Within a UK context, are incentives an acceptable, effective and cost-effective way to help pregnant women who smoke to quit? Design and Methods This study is a phase II exploratory individually randomised controlled trial comparing standard care for pregnant smokers with standard care plus the additional offer of financial voucher incentives to engage with specialist cessation services and/or to quit smoking during pregnancy. Participants (n=600) will be pregnant smokers identified at maternity booking who when contacted by specialist cessation services agree to having their details passed to the NHS Smokefree Pregnancy Study Helpline to discuss the trial. The NHS Smokefree Pregnancy Study Helpline will be responsible for telephone consent and follow-up in late pregnancy. The primary outcome will be self reported smoking in late pregnancy verified by cotinine measurement. An economic evaluation will refine cost data collection and assess potential cost-effectiveness while qualitative research interviews with clients and health professionals will assess the level of acceptance of this form of incentive payment. Research questions What is the likely therapeutic efficacy? Are incentives potentially cost-effective? Is individual randomisation an efficient trial design without introducing outcome bias? Can incentives be introduced in a way that is feasible and acceptable? DISCUSSION: This phase II trial will establish a workable design to reduce the risks associated with a future definitive phase III multicentre randomised controlled trial and establish a framework to assess the costs and benefits of financial incentives to help pregnant smokers to quit. Trial registration: Current Controlled Trials ISRCTN87508788 350 words.     

Web-based smoking cessation intervention that transitions from inpatient to outpatient: study protocol for a randomized controlled trial

ABSTRACT: BACKGROUND: E-health tools are a new mechanism to expand patient care, allowing supplemental resources to usual care, including enhanced patient-provider communication. These applications to smoking cessation have not yet been tested in a hospitalized patient sample. This project aims to evaluate the effectiveness and cost-effectiveness of a tailored web-based and e-message smoking cessation program for current smokers that, upon hospital discharge, transitions the patient to continue a quit attempt when home (Decide2Quit). DESIGN: A randomized two-arm follow-up design will test the effectiveness of an evidence- and theoretically-based smoking cessation program designed for post-hospitalization. METHODS: 1488 patients aged 19 or older, who smoked cigarettes in the previous 30 days, are being recruited from 27 patient care areas of a large urban university hospital. Study eligible hospitalized patients receiving tobacco cessation usual care are offered study referral. Trained hospital staff assist the 744 patients who are being randomized to the intervention arm with registration and orientation to the intervention website. This e-mail and web-based program offers tailored messages as well as education, self-assessment and planning aids, and social support to promote tobacco use cessation. Condition-blind study staff assess participants for tobacco use history and behaviors, tobacco use costs-related information, co-morbidities and psychosocial factors at 0, 3, 6, and 12 months. The primary outcome is self-reported 30-day tobacco abstinence at 6 months follow-up. Secondary outcomes include 7-day point prevalence quit rates at 3, 6, and 12 months follow-up, 30-day point prevalence quit rates at 3 and 12 months, biologically confirmed tobacco abstinence at 6-months follow-up, and multiple point-prevalence quit rates based on self-reported tobacco abstinence rates at each follow-up time period. Health care utilization and quality of life are assessed at baseline, and 6 and 12 months follow-up to measure program cost-effectiveness from the hospital, health care payer, patient, and societal perspectives. DISCUSSION: Given the impact of tobacco use on medical resources, establishing feasible, cost-effective methods for reducing tobacco use is imperative. Given the minimal hospital staff burden and the automated transition to a post-hospitalization tailored intervention, this program could be an easily disseminated approach. Trial Registration: Current Intervention Trial NCT01277250.     

Effectiveness of smoking-cessation interventions for urban hospital patients: study protocol for a randomized controlled trial

ABSTRACT: BACKGROUND: Hospitalization may be a particularly important time to promote smoking cessation, especially in the immediate post-discharge period. However, there are few studies to date that shed light on the most effective or cost-effective methods to provide post-discharge cessation treatment, especially among low-income populations and those with a heavy burden of mental illness and substance use disorders. METHODS: This randomized trial will compare the effectiveness and cost-effectiveness of two approaches to smoking cessation treatment among patients discharged from two urban public hospitals in New York City. During hospitalization, staff will be prompted to ask about smoking and to offer nicotine replacement therapy (NRT) on admission and at discharge. Subjects will be randomized on discharge to one of two arms: One arm will be proactive multi-session telephone counseling with motivational enhancement delivered by study staff, and the other will be a faxed or online referral to the New York State Quitline. The primary outcome is 30-day point-prevalence abstinence from smoking at 6-month follow-up post-discharge. We will also examine cost-effectiveness from a societal and a payer perspective, as well as explore subgroup analyses related to patients' location of hospitalization, race/ethnicity, immigrant status, and inpatient diagnosis. DISCUSSION: This study will explore issues of implementation feasibility in a post-hospitalization patient population, as well as add information about the effectiveness and cost-effectiveness of different strategies for designing smoking cessation programs for hospitalized patients.     

Does Effectiveness of Adolescent Smoking-Cessation Intervention Endure Into Young Adulthood? 7-Year Follow-Up Results from a Group-Randomized Trial

Background

The Hutchinson Study of High School Smoking was the first randomized trial to show effectiveness of a smoking cessation intervention on 6-months prolonged smoking abstinence at one year post-intervention in a large population-based sample of adolescent smokers. An important question remains: Do the positive effects from teen smoking cessation interventions seen at up to 12 months post-intervention endure into young adulthood? This study examines for the first time whether such positive early effects from teen smoking cessation intervention can endure into young adulthood in the absence of additional intervention.

Methods

High school smokers (n = 2,151) were proactively recruited into the trial from fifty randomly selected Washington State high schools randomized to the experimental (Motivational Interviewing + Cognitive Behavioral Skills Training telephone counseling intervention) or control (no intervention) condition. These smokers were followed to 7 years post high school to ascertain rates of six-year prolonged smoking abstinence in young adulthood. All statistical tests are two-sided.

Results

No evidence of intervention impact at seven years post high school was observed for the main endpoint of six-year prolonged abstinence, neither among all smokers (14.2% in the experimental condition vs. 13.1% in the control condition, difference = +1.1%, 95% confidence interval (CI) = -3.4 to 5.8, p = .61), nor among the subgroups of daily smokers and less-than-daily smokers, nor among other a priori subgroups. But, observed among males was some evidence of an intervention impact on two endpoints related to progress towards quitting: reduction in number of days smoked in the past month, and increase in the length of the longest quit attempt in the past year.

Conclusions

There was no evidence from this trial among adolescent smokers that positive effectiveness of the proactive telephone intervention for smoking abstinence, observed previously at one year post-intervention, was sustained for the long-term into young adulthood. In light of the positive short-term effectiveness consistently observed from this and other trials for teen smokers, together with the lack of evidence from this study that such short-term impact can endure into young adulthood, sustained interventions that continue into young adulthood should be developed and tested for long-term impact.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00115882","term_id":"NCT00115882"}}NCT00115882     

No evidence for a major role of polymorphisms during bupropion treatment

This study evaluated the ability of polymorphisms in five candidate genes to predict weight gain among patients taking bupropion or placebo in a smoking cessation trial. Five hundred fifty-three smokers were enrolled into a randomized double-blind, placebo-controlled trial and followed for 12 months. Five candidate genes [DRD2 Taq1 (rs1800497), DRD2-141 (rs1799732), C957T (rs6277), COMT (rs4818), and SLC6A3] were genotyped. Weights at baseline, at end of treatment, and after 6 and 12 months of follow-up were self-reported. Smoking abstinence at each endpoint was self-reported and confirmed biochemically. A self-reported average weight gain after 12 months of 1.1 +/- 6.0 kg (mean +/- standard deviation) in the bupropion group and 1.8 +/- 4.8 kg in the placebo group was noted. For subjects with biochemically confirmed abstinence from smoking, the HL genotype (alleles coding Val at codon 108 are denoted as H, and those coding Met are denoted as L) at the COMT locus and A1A1 genotype at the DRD2 Taq1 locus were associated with less weight gain at the end of treatment. The TC genotype at the C957T locus was associated with increased weight gain at 6 months of follow-up. However, no polymorphisms or their interactions with bupropion consistently and significantly predicted baseline BMI or weight change during treatment for all study subjects. Overall, our results do not support a major role for these five candidate genes in weight gain after smoking cessation.     

Randomised controlled trial of smoking cessation intervention after admission for coronary heart disease

Objective To determine whether a nurse led smoking cessation intervention affects smoking cessation rates in patients admitted for coronary heart disease.Design Randomised controlled trial.Setting Cardiac ward of a general hospital, Norway.Participants 240 smokers aged under 76 years admitted for myocardial infarction, unstable angina, or cardiac bypass surgery. 118 were randomly assigned to the intervention and 122 to usual care (control group).Intervention The intervention was based on a booklet and focused on fear arousal and prevention of relapses. The intervention was delivered by cardiac nurses without special training. The intervention was initiated in hospital, and the participants were contacted regularly for at least five months.Main outcome measure Smoking cessation rates at 12 months determined by self report and biochemical verification.Results 12 months after admission to hospital, 57% (n = 57/100) of patients in the intervention group and 37% (n = 44/118) in the control group had quit smoking (absolute risk reduction 20%, 95% confidence interval 6% to 33%). The number needed to treat to get one additional person who would quit was 5 (95% confidence interval, 3 to 16). Assuming all dropouts relapsed at 12 months, the smoking cessation rates were 50% in the intervention group and 37% in the control group (absolute risk reduction 13%, 0% to 26%).Conclusion A smoking cessation programme delivered by cardiac nurses without special training, significantly reduced smoking rates in patients 12 months after admission to hospital for coronary heart disease.     

Using "warm handoffs" to link hospitalized smokers with tobacco treatment after discharge: Study protocol of a randomized controlled trial

ABSTRACT: BACKGROUND: Post-discharge support is a key component of effective treatment for hospitalized smokers, but few hospitals provide it. Many hospitals and care settings fax refer smokers to quitlines for follow up, however, less than half of fax-referred smokers are successfully contacted and enrolled in quitline services. "Warm handoff" is a novel approach to care transitions in which health care providers directly link patients with substance abuse problems with specialists, using face-to-face or phone transfer. Warm handoff achieves very high rates of treatment enrollment for these vulnerable groups. METHODS: The aim of this study--"EQUIP" (Enhancing Quitline Utilization among In-Patients)--is to determine the effectiveness, and cost-effectiveness, of warm handoff versus fax referral for linking hospitalized smokers with tobacco quitlines. This study employs a two-arm, individually randomized design. It is set in two large Kansas hospitals that have dedicated tobacco treatment interventionists on staff. At each site, smokers who wish to remain abstinent after discharge will be randomly assigned to groups. For patients in the fax group, staff will provide standard in-hospital intervention and will fax-refer patients to the state tobacco quitline for counseling post-discharge. For patients in the warm handoff group, staff will provide brief in-hospital intervention and immediate warm handoff: staff will call the state quitline, notify them that a warm handoff inpatient from Kansas is on the line, then transfer the call to the patients' mobile or bedside hospital phone for quitline enrollment and an initial counseling session. Following the quitline session, hospital staff provide a brief check-back visit. Costs are measured to support cost-effectiveness analyses. We hypothesize that warm handoff, compared to fax referral, will improve care transitions for tobacco treatment, enroll more participants in quitline services and lead to higher quit rates. We also hypothesize that warm handoff will be more cost-effective from a societal perspective. Outcome measures will be assessed at 1, 6, and 12-months post enrollment. DISCUSSION: If successful, this project offers a low-cost solution for more efficiently linking millions of hospitalized smokers with effective outpatient treatment--smokers that might otherwise be lost in the transition to outpatient care. Trial registration: Clinical Trials Registration NCT01305928 Key words: Tobacco use disorder, smoking cessation, hospital, randomized clinical trial.     

Electronic Cigarettes Efficacy and Safety at 12 Months: Cohort Study

Objective

To evaluate the safety and efficacy as a tool of smoking cessation of electronic cigarettes (e-cigarettes), directly comparing users of e-cigarettes only, smokers of tobacco cigarettes only, and smokers of both.

Design

Prospective cohort study. Final results are expected in 2019, but given the urgency of data to support policies on electronic smoking, we report the results of the 12-month follow-up.

Data Sources

Direct contact and structured questionnaires by phone or via internet.

Methods

Adults (30–75 years) were included if they were smokers of ≥1 tobacco cigarette/day (tobacco smokers), users of any type of e-cigarettes, inhaling ≥50 puffs weekly (e-smokers), or smokers of both tobacco and e-cigarettes (dual smokers). Carbon monoxide levels were tested in a sample of those declaring tobacco smoking abstinence.

Main Outcome Measures

Sustained smoking abstinence from tobacco smoking at 12 months, reduction in the number of tobacco cigarettes smoked daily.

Data Synthesis

We used linear and logistic regression, with region as cluster unit.

Results

Follow-up data were available for 236 e-smokers, 491 tobacco smokers, and 232 dual smokers (overall response rate 70.8%). All e-smokers were tobacco ex-smokers. At 12 months, 61.9% of the e-smokers were still abstinent from tobacco smoking; 20.6% of the tobacco smokers and 22.0% of the dual smokers achieved tobacco abstinence. Adjusting for potential confounders, tobacco smoking abstinence or cessation remained significantly more likely among e-smokers (adjusted OR 5.19; 95% CI: 3.35–8.02), whereas adding e-cigarettes to tobacco smoking did not enhance the likelihood of quitting tobacco and did not reduce tobacco cigarette consumption. E-smokers showed a minimal but significantly higher increase in self-rated health than other smokers. Non significant differences were found in self-reported serious adverse events (eleven overall).

Conclusions

Adding e-cigarettes to tobacco smoking did not facilitate smoking cessation or reduction. If e-cigarette safety will be confirmed, however, the use of e-cigarettes alone may facilitate quitters remaining so.

Registration Number

NCT01785537.     

The implication of cigarette smoking and cessation on macrophage cholesterol efflux in coronary artery disease patients

We investigated ATP-binding cassette transporters A1/G1 expression and function in mediating cholesterol efflux by examining the macrophages of cigarette-smoking patients with coronary artery disease (CAD) before and after smoking abstinence. Peripheral blood monocyte cells were collected from nonsmokers (n = 17), non-CAD (NCAD) smokers (n = 35), and CAD smokers (n = 32) before and after 3 months of smoking cessation. We found that the ABCA1 expression level was lower in macrophages from NCAD and CAD smokers than from nonsmokers at baseline. The ABCA1 function of mediating cholesterol efflux was reduced in NCAD and CAD smokers as compared with nonsmokers. After 3 months of smoking cessation, ABCA1 expression and function were improved in CAD smokers. However, ABCG1 expression and function did not change after smoking cessation. Furthermore, ABCA1 expression was inhibited by tar in human acute monocytic leukemia cell line THP-1-derived macrophages through the inhibition of liver X receptors. Nicotine and carbon monoxide did not inhibit ABCA1 expression. Our results indicate that chronic cigarette smoking impaired ABCA1-mediated cholesterol efflux in macrophages and that tobacco abstinence reversed the function and expression of ABCA1, especially in CAD patients. It was tobacco tar, rather than nicotine or carbon monoxide, that played a major role in the tobacco-induced disturbance of cellular cholesterol homeostasis.     

Self-help materials for the prevention of smoking relapse: study protocol for a randomised controlled trial

ABSTRACT: BACKGROUND: Most people who stop smoking successfully for a few weeks will return to smoking again in the medium term. There are few effective interventions to prevent this relapse and none used routinely in clinical practice. A previous exploratory meta-analysis suggested that self-help booklets may be effective but requires confirmation. This trial aims to evaluate the effectiveness and cost-effectiveness of a set of self-help educational materials to prevent smoking relapse in the NHS Stop Smoking Service. METHODS: This is an open, randomised controlled trial. The target population is carbon monoxide (CO) verified quitters at 4 weeks in the NHS stop smoking clinic (total sample size N=1,400). The experimental intervention tested is a set of 8 revised Forever Free booklets, including an introduction booklet and more extensive information on all important issues for relapse prevention. The control intervention is a leaflet that has no evidence to suggest it is effective but is currently given to some patients using NHS stop smoking services. Two follow-up telephone interviews will be conducted at 3 and 12 months after quit date. The primary outcome will be prolonged abstinence from months 4-12 with no more than 5 lapses, confirmed by carbon monoxide test at 12 month assessment. The secondary outcomes will be 7-day self-report point prevalence abstinence at 3 months and 7-day biochemically confirmed point prevalence abstinence at 12 months. To assess cost-effectiveness, costs will be estimated from a health service perspective and the EQ-5D will be used to estimate the QALY (Quality Adjusted Life Year) gain associated with each intervention. The comparison of smoking abstinence rates (and any other binary outcomes) between the two trial arms will be carried out using odds ratio as the outcome statistic and other related statistical tests. Exploratory subgroup analyses, including logistic regression analyses with interaction terms, will be conducted to investigate possible effect modifying variables. DISCUSSION: The possible effect of self-help educational materials for the prevention of smoking relapse has important public health implications. Trial Registration: Current Controlled Trials ISRCTN36980856.     

The Consequences of High Cigarette Excise Taxes for Low-Income Smokers

Background

To illustrate the burden of high cigarette excise taxes on low-income smokers.

Methodology/Principal Findings

Using data from the New York and national Adult Tobacco Surveys from 2010–2011, we estimated how smoking prevalence, daily cigarette consumption, and share of annual income spent on cigarettes vary by annual income (less than $30,000; $30,000–$59,999; and more than $60,000). The 2010–2011 sample includes 7,536 adults and 1,294 smokers from New York and 3,777 adults and 748 smokers nationally. Overall, smoking prevalence is lower in New York (16.1%) than nationally (22.2%) and is strongly associated with income in New York and nationally (P<.001). Smoking prevalence ranges from 12.2% to 33.7% nationally and from 10.1% to 24.3% from the highest to lowest income group. In 2010–2011, the lowest income group spent 23.6% of annual household income on cigarettes in New York (up from 11.6% in 2003–2004) and 14.2% nationally. Daily cigarette consumption is not related to income.

Conclusions/Significance

Although high cigarette taxes are an effective method for reducing cigarette smoking, they can impose a significant financial burden on low-income smokers.     

Factors Associated with Tobacco Smoking and Cessation among HIV-Infected Individuals under Care in Rio de Janeiro,Brazil

Worldwide the prevalence of smoking among people living with HIV/AIDS is elevated compared to the general population. This probably reflects the cluster of individual characteristics that have shared risk factors for HIV infection and smoking. A cross-sectional study, enrolling a convenience sample from a Brazilian HIV clinical cohort was conducted to evaluate the prevalence of tobacco smoking and the factors associated with current smoking and abstinence. A total of 2,775 HIV-infected individuals were interviewed: 46.2% have never smoked, 29.9% were current smokers and 23.9% were former smokers. Current smokers had a higher prevalence of alcohol and illicit drug use when compared to the other two groups. A higher proportion of heterosexual individuals were former smokers or never smokers while among men who have sex with men (MSM) a higher proportion were current smokers. Former smokers had been more frequently diagnosed with high blood pressure, diabetes mellitus, cardiovascular diseases and depression, while for current smokers lung diseases were more frequent. Former smokers and current smokers were more likely to have had any hospital admission (42.0% and 41.2%, respectively) than participants who never smoked (33.5%) (p<0.001). Multivariate model results showed that current smokers (versus never smokers) were more likely to be less educated, to report the use of alcohol, crack and cocaine and to present clinical comorbidities. Former smokers (versus current smokers) were more likely to be older, to have smoked for a shorter amount of time and to have smoked >31 cigarettes/day. MSM (compared to heterosexuals) and cocaine users (versus non-users) had lower odds of being former smokers. Considering our results, smoking cessation interventions should be tailored to younger individuals, MSM and substance users.     

Nortriptyline plus nicotine replacement versus placebo plus nicotine replacement for smoking cessation: pragmatic randomised controlled trial

Objective To test the efficacy of nortriptyline plus nicotine replacement therapy compared with placebo plus nicotine replacement therapy for smoking cessation.Design Pragmatic randomised controlled trial.Setting National Health Service stop smoking service clinics.Participants 901 people trying to stop smoking.Interventions Participants chose their nicotine replacement product, including combinations of nicotine replacement therapy, and received behavioural support. Nortriptyline was started one to two weeks before quit day, with the dose increased from 25 mg to 75 mg daily for eight weeks and reduced if not tolerated.Main outcome measures Primary outcome was prolonged confirmed abstinence at six months. Secondary outcomes were prolonged abstinence at 12 months, drug use, severity of side effects, nicotine withdrawal symptoms, and urges to smoke.Results 72 of 445 (16%) people using nortriptyline and 55 of 456 (12%) using placebo achieved prolonged abstinence at six months (relative risk 1.34, 95% confidence interval 0.97 to 1.86). At 12 months the corresponding values were 49 (11%) for nortriptyline and 40 (9%) for placebo (1.26, 0.84 to 1.87). 337 (79%) people in the nortriptyline arm and 325 (75%) in the placebo arm were taking combination treatment on quit day, median 75 mg per day in both groups. More people in the nortriptyline arm than in the placebo arm took lower doses. The nortriptyline arm had noticeably higher severity ratings for dry mouth and constipation than the placebo arm, with slightly higher ratings for sweating and feeling shaky. Both groups had similar urges to smoke, but nortriptyline reduced depression and anxiety. Overall, withdrawal symptom scores did not differ.Conclusions Nortriptyline and nicotine replacement therapy are both effective for smoking cessation but the effect of the combination is less than either alone and evidence is lacking that combination treatment is more effective than either alone.Trial registration Current Controlled Trials ISRCTN57852484.     

Smoking cessation and subsequent risk of cancer: A pooled analysis of eight population-based cohort studies in Japan

BackgroundAlthough East Asia is one of the largest tobacco-epidemic regions in the world, only a few prospective studies from Asia have investigated the impact of smoking and cessation of smoking on cancer. We aimed to assess the effect of cessation of smoking on the risk of cancer using eight population-based cohort studies in Japan.MethodsWe analyzed pooled data from eight population-based prospective cohort studies in Japan with more than 320,000 participants to assess the effect of smoking cessation on the risk of total cancers and smoking-related cancers.ResultsAfter adjustment for potential confounders, cancer risks in men with >21 years of smoking cessation before baseline were found to decrease to the same level as never smokers for total cancer (never smokers: reference; former smokers with ≥21 years since smoking cessation: HR, 1.01; 95%CI: 0.91, 1.11). Even men who are heavy smokers (more than 20 pack-years) reported a reduced risk of total cancer (never smokers: reference; former smokers with ≥21 years since smoking cessation: HR, 1.06; 95%CI: 0.92, 1.23). In women, the risk of total cancer did not differ from that of never smokers after 11 years of smoking cessation before baseline (never smokers: reference; former smokers with ≥11 years since smoking cessation: HR, 0.96; 95%CI: 0.74, 1.23).ConclusionsOur study suggests that longer duration of smoking cessation may attenuate the risk of cancer in both men and women, and that even heavy smokers (more than 20 pack-years) were found to benefit from quitting smoking.     

Effects of smoking and cessation on subclinical arterial disease: a substudy of a randomized controlled trial

Background

The mechanisms by which smoking cessation reduces cardiovascular disease risk are unclear. We evaluated longitudinal changes in carotid intima-media thickness among current smokers enrolled in a prospective, randomized smoking cessation clinical trial.

Methodology/Principal Findings

Subjects were enrolled in a randomized, double-blind, placebo-controlled trial of 5 smoking cessation pharmacotherapies and underwent carotid ultrasonography with carotid intima-media thickness measurement. Subjects were classified as continuously abstinent (biochemically confirmed abstinence at 6 months, 1 year, and 3 years post-quit attempt), intermittently abstinent (reported smoking at one of the three time points), or smoked continuously (reported smoking at all three time points). The primary endpoint was the absolute change (mm) in carotid intima-media thickness (ΔCIMT_max) before randomization and 3 years after the target quit date. Pearson correlations were calculated and multivariable regression models (controlling for baseline CIMT_max and research site) were analyzed. Among 795 subjects (45.2±10.6 years old, 58.5% female), 189 (23.8%) were continuously abstinent, 373 (46.9%) smoked continuously, and 233 (29.3%) were abstinent intermittently. There was a greater increase in carotid intima-media thickness among subjects who were continuously abstinent than among those who smoked continuously (p = 0.020), but not intermittently (p = 0.310). Antihypertensive medication use (p = 0.001) and research site (p<0.001) independently predicted ΔCIMTmax – not smoking status. The greatest increase in carotid intima-media thickness among continuous abstainers was related to increases in body-mass index (p = 0.043).

Conclusions/Significance

Smoking status did not independently predict ΔCIMT_max; increasing body-mass index and antihypertensive medication use were the most important independent predictors. The rapid reduction in cardiovascular disease events observed with smoking cessation is unlikely to be mediated by changes in subclinical atherosclerosis burden.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00332644","term_id":"NCT00332644"}}NCT00332644     

Effects of the multiple risk factor intervention trial smoking cessation program on pulmonary function. A randomized controlled trial.

To determine whether the decline in pulmonary function in smokers is modified by stop-smoking intervention, a randomized controlled study (the Multiple Risk Factor Intervention Trial) was done comparing participants in a special intervention group that included an intensive smoking cessation program with those assigned to usual care. The subjects were 6,347 middle-aged male smokers who had serial measurements of pulmonary function--principally the forced expiratory volume in 1 second (FEV1)--during 6 to 7 years of follow-up. No overall differences were detected in the rate of loss of FEV1 in the two groups. The use of beta-blockers, which had detrimental effects on FEV1, was significantly more common in the intervention group. Among nonusers of beta-blockers, heavy smokers lost FEV1 at a rate about 11 ml per year slower in the intervention group than in the control group (2P = .09) and ended the trial with an FEV1 about 90 ml higher (2P = .05). These results support the inference from observational studies that smoking cessation has a beneficial effect on pulmonary function in heavy smokers.     

Smoking enhances the expression of angiotensin-converting enzyme 2 involved in the efficiency of severe acute respiratory syndrome coronavirus 2 infection

Smoking is one of the risk factors most closely related to the severity of coronavirus disease 2019 (COVID-19). However, the relationship between smoking history and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity is unknown. In this study, we evaluated the ACE2 expression level in the lungs of current smokers, ex-smokers, and nonsmokers. The ACE2 expression level of ex-smokers who smoked cigarettes until recently (cessation period shorter than 6 months) was higher than that of nonsmokers and ex-smokers with a long history of nonsmoking (cessation period longer than 6 months). We also showed that the efficiency of SARS-CoV-2 infection was enhanced in a manner dependent on the angiotensin-converting enzyme 2 (ACE2) expression level. Using RNA-seq analysis on the lungs of smokers, we identified that the expression of inflammatory signaling genes was correlated with ACE2 expression. Notably, with increasing duration of smoking cessation among ex-smokers, not only ACE2 expression level but also the expression levels of inflammatory signaling genes decreased. These results indicated that smoking enhances the expression levels of ACE2 and inflammatory signaling genes. Our data suggest that the efficiency of SARS-CoV-2 infection is enhanced by smoking-mediated upregulation of ACE2 expression level.     

Efficacy of genotype notification to Japanese smokers on smoking cessation—An intervention study at workplace

Objectives: It is well-known that smoking causes many diseases including cancers. Informing smokers of their genotypes associated with the vulnerability to the harms of smoking may be effective measures for smoking cessation. The present study examined the effects of genotype notification of an oncogene (L-myc) genotype to smokers on their behavior to quit smoking. Methods: Subjects were 562 employees of a bank who answered to be a smoker for a questionnaire used at annual health checkup at workplace from July to December 2002. Those enrolled on August, October, and December were allocated into the genotype notification group (intervention group), and the rest into the controls. Among 286 smokers allocated into the intervention group, 257 participants (89.9%) agreed to genotype testing. One year after the enrollment, a follow-up questionnaire survey was conducted for all smokers including controls. Results: Those who stated to have quitted smoking were 22 (8.0%) among the 276 controls and 15 (5.8%) among the 257 genotype notified participants, providing that the odds ratio (OR) of cessation for the intervention was 0.64 (95% confidence interval, 0.32–1.28). No psychological problems associated with genotype notification were observed. Conclusion: The present study did not show positive effects of genotype notification on smoking cessation rate. To elevate the cessation rate, methods to explain and notify genotypes should be improved.     

Associations of smoking cessation with visceral fat area and prevalence of metabolic syndrome in men: the Hitachi health study

Weight gain after smoking cessation may deteriorate metabolic risk profiles, including that for metabolic syndrome. How risk profiles change according to the duration of smoking cessation and whether the visceral fat area (VFA) or the subcutaneous fat area (SFA) contributes to these changes remains uncertain. The subjects comprised 5,697 Japanese men who underwent an abdominal computed-tomography examination during a health check-up. Using never smokers as a reference group, the odds ratios of having metabolic syndrome and its components, defined using the National Cholesterol Education Program Adult Treatment Panel IIIcriteria, were calculated for each smoking category with adjustments for age, alcohol drinking, and physical activity (model 1) using a logistic regression analysis. Additional adjustments were also made for either VFA (model 2) or SFA (model 3). Current smokers had the lowest VFA (120.4 cm2) whereas ex-smokers (124.0-132.0 cm2) had a higher VFA than nonsmokers (123.1 cm2). Among the ex-smokers, VFA tended to decrease with increasing years of smoking cessation. In model 1, the odds ratios of having metabolic syndrome for current smokers and ex-smokers with smoking cessation for ≤ 4, 5-9, 10-14, and ≥ 15 years were 1.02, 1.33, 1.36, 1.40, and 1.09, respectively. The elevated odds ratios among ex-smokers (≤ 14 years) were reduced by 35-55.6% after further adjustment for VFA but not for SFA. Smoking cessation is associated with a deterioration of the metabolic risk profile, which can be ascribed, at least in part, to an increase in VFA not SFA.