Validation of smoking cessation self-reported by patients with chronic obstructive pulmonary disease

"Boy, what are we all doing? We are crazy, really crazy": a qualitative study of psychosocial processes around an atypical one-time smoking cessation course

BACKGROUND

Smoking prevalence is still high, which requires effective interventions that help many people who smoke at once in addition to time-consuming individual interventions. 'I Quit' is a large-scale smoking cessation course in The Netherlands. This qualitative study explored I Quit participants' experiences during and after the course, and perceptions of whether and how the course may have altered their smoking behavior.

METHODS

We performed individual semi-structured interviews with course participants (N = 21) who had either quit successfully, attempted to quit but relapsed, or had continued to smoke after 'I Quit'. Shortly after qualitative data collection was completed, Foundation I Quit was accused in the media of a number of misbehaviors. Although unplanned, this provided a unique opportunity to explore participants' views on alleged fraud in a second round of interviews (N = 16). Data were collected from 2016 to 2018.

RESULTS

Qualitative findings showed two psychosocial processes that may explain smoking cessation after course attendance. First, the confrontation with a large group of people who smoke, of whom some had already developed smoking-related complaints, triggered identity processes both towards and away from quitting smoking. Unorthodox methods used in the course appeared to trigger identity processes. Second, social support after the course from participants' own social network facilitated maintenance of successful quitting. The study also found that interview participants' opinions on I Quit did not change much after allegations of fraud in the media.

CONCLUSIONS

Findings suggest that a one-time course might initiate psychosocial processes that could help certain smokers to gain motivation to quit, requiring a minimum of resources. Identity processes triggered by the course seem tricky as people have different ways of dealing with identity threat, some of which can be counterproductive and even result in more difficulty quitting. More research is needed to examine who can benefit from a one-time course, and who needs more support in order to quit successfully.

Assessing tobacco use in Swedish young adults from self-report and urinary cotinine: a validation study using the BAMSE birth cohort

OBJECTIVES

Studies on health effects of tobacco often rely on self-reported exposure data, which is subjective and can lead to misclassification. The aim of this study was to describe the prevalence of cigarette smoking, snus and e-cigarette use, as well as to validate self-reported tobacco use among young adults in Sweden.

METHOD

Participants of a population-based Swedish cohort (n=3052), aged 22-25 years, assessed their tobacco use in a web questionnaire. Urinary cotinine was analysed in a subsample of the study population (n=998). The agreement between self-reported tobacco use and urinary cotinine was assessed using Cohen's Kappa coefficient (κ) at a cut-off level of 50 ng/mL.

RESULTS

Patterns of tobacco use differed between men and women. Among men, 20.0% reported daily snus use, 5.8% daily cigarette smoking and 5.6% any e-cigarette use. In contrast, 3.2% of the women reported daily snus use, 9.0% daily cigarette smoking and 2.4% any e-cigarette use. Among the tobacco use categories, daily snus users had the highest levels of cotinine. Of reported non-tobacco users, 3.5% had cotinine levels above the cut-off, compared with 68.0% among both occasional cigarette smokers and snus users, 67.5% among all e-cigarette users and 94.7% and 97.8% among daily cigarette smokers and snus users, respectively. Agreement between self-reported tobacco use and urinary cotinine was classified as strong for daily use of cigarettes (κ=0.824) and snus (κ=0.861), while moderate to weak for occasional smoking (κ=0.618), occasional snus use (κ=0.573) and any e-cigarette use (κ=0.576).

CONCLUSIONS

We found high validity of self-reported tobacco use in our study population, particularly for daily tobacco use. Further, we found that daily snus users were exposed to high levels of cotinine. Together with previous findings, our results indicate good validity of self-reported tobacco use among young adults.

Monitoring expiratory carbon monoxide to study the effect of complete smoking cessation on definitive radiation therapy for early stage glottic carcinoma

BACKGROUND

Previous studies reported that cigarette smoking during radiation therapy was associated with unfavorable outcomes in various cancers using medical interviewing or monitoring of cotinine. Here, we evaluated the effect of smoking cessation on definitive radiation therapy for early stage glottic carcinoma by monitoring expiratory carbon monoxide (CO).

MATERIAL AND METHODS

We enrolled 103 patients with early glottic carcinoma (T1N0/T2N0 = 79/24) who underwent conventional radiotherapy between 2005 and 2016. The median age was 70 years. Pathologically, all patients had squamous cell carcinoma. Since 2009, we confirmed smoking cessation before radiation therapy by medical interviews. Since 2014, we measured expiratory CO to strictly monitor smoking cessation. The patients were divided according to diagnosis years: 'no cessation' (2005-2008), 'incomplete cessation' (2009-2013), and 'complete cessation' (2014-2016). We retrospectively analyzed the local recurrence rate and disease-free survival (DFS).

RESULTS

The median follow-up period was 60.1 months (range, 1.9-110.0 months). The 2-year local recurrence rate in the 'complete cessation' group was 5.3% and tended to be lower than that in the 'incomplete cessation' group (13.7%) and 'no cessation' group (21.2%). Multivariate analysis revealed that 'no cessation' was a risk factor for DFS (hazard ratio [HR] = 4.25) and local recurrence rate (HR = 16.5, p < .05) compared to 'complete cessation.'

DISCUSSION

We confirmed that the 'complete cessation' group had better prognosis than the 'no cessation' group by monitoring expiratory CO during radiation therapy for early stage glottic carcinoma. Moreover, monitoring expiratory CO was easier and more suitable than conventional methods for evaluating smoking cessation because it provided real-time measurements.

The Influence of Smoking Status on Exhaled Breath Profiles in Asthma and COPD Patients

Breath analysis using eNose technology can be used to discriminate between asthma and COPD patients, but it remains unclear whether results are influenced by smoking status. We aim to study whether eNose can discriminate between ever- vs. never-smokers and smoking <24 vs. >24 h before the exhaled breath, and if smoking can be considered a confounder that influences eNose results. We performed a cross-sectional analysis in adults with asthma or chronic obstructive pulmonary disease (COPD), and healthy controls. Ever-smokers were defined as patients with current or past smoking habits. eNose measurements were performed by using the SpiroNose. The principal component (PC) described the eNose signals, and linear discriminant analysis determined if PCs classified ever-smokers vs. never-smokers and smoking <24 vs. >24 h. The area under the receiver–operator characteristic curve (AUC) assessed the accuracy of the models. We selected 593 ever-smokers (167 smoked <24 h before measurement) and 303 never-smokers and measured the exhaled breath profiles of discriminated ever- and never-smokers (AUC: 0.74; 95% CI: 0.66–0.81), and no cigarette consumption <24h (AUC 0.54, 95% CI: 0.43–0.65). In healthy controls, the eNose did not discriminate between ever or never-smokers (AUC 0.54; 95% CI: 0.49–0.60) and recent cigarette consumption (AUC 0.60; 95% CI: 0.50–0.69). The eNose could distinguish between ever and never-smokers in asthma and COPD patients, but not recent smokers. Recent smoking is not a confounding factor of eNose breath profiles.

Two-year efficacy of varenicline tartrate and counselling for inpatient smoking cessation (STOP study): A randomized controlled clinical trial

INTRODUCTION

Varenicline tartrate is superior for smoking cessation to other tobacco cessation therapies by 52 weeks, in the outpatient setting. We aimed to evaluate the long-term (104 week) efficacy following a standard course of inpatient-initiated varenicline tartrate plus Quitline-counselling compared to Quitline-counselling alone.

METHODS

Adult patients (n = 392, 20-75 years) admitted with a smoking-related illnesses to one of three hospitals, were randomised to receive either 12-weeks of varenicline tartrate (titrated from 0.5mg daily to 1mg twice-daily) plus Quitline-counselling, (n = 196) or Quitline-counselling alone, (n = 196), with continuous abstinence from smoking assessed at 104 weeks.

RESULTS

A total of 1959 potential participants were screened for eligibility between August 2008 and December 2011. The proportion of participants who remained continuously abstinent (intention-to-treat) at 104 weeks were significantly greater in the varenicline tartrate plus counselling arm (29.2% n = 56) compared to counselling alone (18.8% n = 36; p = 0.02; odds ratio 1.78; 95%CI 1.10 to 2.86, p = 0.02). Twenty-two deaths occurred during the 104 week study (n = 10 for varenicline tartrate plus counselling and n = 12 for Quitline-counselling alone). All of these participants had known or developed underlying co-morbidities.

CONCLUSIONS

This is the first study to examine the efficacy and safety of varenicline tartrate over 104 weeks within any setting. Varenicline tartrate plus Quitline-counselling was found to be an effective opportunistic treatment when initiated for inpatient smokers who had been admitted with tobacco-related disease.

No association between smoking and sentinel lymph node metastasis and survival in cutaneous melanoma

BACKGROUND

There is little evidence that smoking is associated with metastasis in patients with cutaneous melanoma.

OBJECTIVE

Using a propensity score matching analysis, we assessed whether smoking was associated with a higher rate of sentinel lymph node (SLN) metastasis and worse survival in these patients.

METHODS

Retrospective cohort study at a referral hospital for melanoma. We studied 762 patients with known smoking status from the melanoma database of the Instituto Valenciano de Oncología who underwent SLN biopsy between 1 January 2000 and 31 December 2016. The patients were matched by smoking status. The matching procedure was implemented using three logistic regression models featuring never vs. former smokers, never vs. current smokers and former vs. current smokers. The study outcomes were disease-free survival (DFS), melanoma-specific survival (MSS), overall survival (OS) and SLN status.

RESULTS

The following groups were formed based on the propensity matching scores: 114 pairs of smokers vs. never smokers, 113 pairs of smokers vs. former smokers and 174 pairs of never smokers vs. former smokers. Smoking status was not associated with SLN metastasis or with DFS, MSS or OS in any of the three groups.

CONCLUSION

Smoking does not influence SLN metastasis or survival in patients with cutaneous melanoma.

Consistency and reliability of smoking-related variables: longitudinal study design in asthma and COPD

Introduction: Smoking has a significant impact on the development and progression of asthma and chronic obstructive pulmonary disease (COPD). Self-reported questionnaires and structured interviews are usually the only way to study patients' smoking history. In this study, we aim to examine the consistency of the responses of asthma and COPD patients to repeated standardised questions on their smoking habits over the period of 10 years. Methods: The study population consisted of 1329 asthma and 959 COPD patients, who enrolled in the study during years 2005-2007. A follow-up questionnaire was mailed to the participants 1, 2, 4, 6, 8, and 10 years after the recruitment. Results: Among the participants who returned three or more questionnaires (N = 1454), 78.5 % of the patients reported unchanged smoking status (never smoker, ex-smoker or current smoker) across the time. In 4.5% of the answers, the reported smoking statuses were considered unreliable/conflicting (first never smoker and, later, smoker or ex-smoker). The remainder of the patients changed their status from current smoker to ex-smoker and vice versa at least once, most likely due to struggling with quitting. COPD patients were more frequently heavy ex- or current smokers compared to the asthma group. The intraclass coefficient correlations between self-reported starting (0.85) and stopping (0.94) years as well as the consumption of cigarettes (0.74) over time showed good reliability among both asthma and COPD patients. Conclusion: Self-reported smoking data among elderly asthma and COPD patients over a 10-year follow-up is reliable. Pack years can be considered a rough estimate for their comprehensive consumption of tobacco products over time. We also observed that the questionnaire we used was not designed for dynamic changes in smoking which are rather common among heavy smokers especially when the follow-up time is several years, as in our study.

A Droplet Digital PCR Assay for Smoking Predicts All-Cause Mortality

OBJECTIVES

-Determine whether an epigenetic assay for smoking predicts all-cause mortality in adults participating in a longitudinal study of Iowa adoptees.

BACKGROUND

-Improved biomarkers for smoking are needed given its large public health impact and significant limitations of both self-report and current biomarkers, such as cotinine in detecting smoking. In the past 5 years, multiple epigenome-wide association studies of smoking have identified loci suitable for translation as epigenetic biomarkers for smoking, in particular the CpG cg05575921. Digital polymerase chain reaction methods hold promise for the development of this and other epigenetic biomarkers.

METHODS

-Participants in the Iowa Adoption Studies were interviewed regarding their smoking habits. DNA was prepared from whole blood and bisulfite-converted for methylation analysis and digital droplet polymerase chain reaction assay of methylation at cg05575921 was performed. National Death Index records were requested for 584 study participants, resulting in 24 complete matches, 210 partial matches and 350 non-matching records. Complete matches were coded as deceased while the remainder were coded as alive (ie, censored). In total, methylation data and vital status information were available for a total of N = 193 subjects, including 15 deceased and 178 non-deceased. Cox regression was used to examine the ability of cg05575921 methylation as a continuous value to predict the timing of mortality with and without the inclusion of age, sex, race, BMI, marital status, educational status, socioeconomic status, cardiovascular risk factors, and a history of cancer as covariates.

RESULTS

-Methylation at cg05575921 predicted the hazard of mortality as the sole predictor and after accounting for major demographic and clinical risk factors. The fitted model showed the hazard ratio increased by 3.5% for every 1% decrease in methylation.

CONCLUSIONS

-Decreased methylation at cg05575921, an emerging epigenetic biomarker for smoking, was associated with early mortality in a longitudinal study of adults after accounting for the impact of major demographic and clinical risk factors for all-cause mortality. This approach may be useful in clinical research or actuarial assessments.

The genetics of smoking in individuals with chronic obstructive pulmonary disease

Background

Smoking is the principal modifiable environmental risk factor for chronic obstructive pulmonary disease (COPD) which affects 300 million people and is the 3rd leading cause of death worldwide. Most of the genetic studies of smoking have relied on self-reported smoking status which is vulnerable to reporting and recall bias. Using data from the Lung Health Study (LHS), we sought to identify genetic variants associated with quantitative smoking and cessation in individuals with mild to moderate COPD.

Methods

The LHS is a longitudinal multicenter study of mild-to-moderate COPD subjects who were all smokers at recruitment. We performed genome-wide association studies (GWASs) for salivary cotinine (n = 4024), exhaled carbon monoxide (eCO) (n = 2854), cigarettes per day (CPD) (n = 2706) and smoking cessation at year 5 follow-up (n = 717 quitters and 2175 smokers). The GWAS analyses were adjusted for age, gender, and genetic principal components.

Results

For cotinine levels, SNPs near UGT2B10 gene achieved genome-wide significance (i.e. P < 5 × 10^− 8) with top SNP rs10023464, P = 1.27 × 10^− 11. For eCO levels, one significant SNP was identified which mapped to the CHRNA3 gene (rs12914385, P = 2.38 × 10^− 8). A borderline region mapping to KCNMA1 gene was associated with smoking cessation (rs207675, P = 5.95 × 10^− 8). Of the identified loci, only the CHRNA3/5 locus showed significant associations with lung function but only in heavy smokers. No regions met genome-wide significance for CPD.

Conclusion

The study demonstrates that using objective measures of smoking such as eCO and/or salivary cotinine can more precisely capture the genetic contribution to multiple aspects of smoking behaviour. The KCNMA1 gene association with smoking cessation may represent a potential therapeutic target and warrants further studies.

Trial registration

The Lung Health Study ClinicalTrials.gov Identifier: NCT00000568. Date of registration: October 28, 1999.

Electronic supplementary material

The online version of this article (10.1186/s12931-018-0762-7) contains supplementary material, which is available to authorized users.

Outcomes for a Public Hospital Tobacco Cessation Program: The Cook County Health and Hospitals System Experience

The objective of this study is to determine the rate and predictors of sustained smoking cessation for a cohort of smokers exposed to a guideline-based health education program delivered during routine clinical care at an urban public hospital. This is a retrospective analysis of 755 public hospital system patients who had at least two health educator contacts embedded in routine clinical care, with the latter contact 12-18 months after the baseline. The education occurred during visits to primary care, specialty clinics, urgent/episodic care, or during hospitalization. The assessment of smoking status is determined by the health educators as part of their routine assessment and recorded in the program's database. The primary outcomes are self-reported 12-month sustained smoking cessation at the 12-18 month contact and predictors of cessation. The cohort is predominantly minority smokers (African American 69 % and Latino 15 %) and uninsured (70 %) or on Medicaid (13 %). The sustained cessation rate was 9.3 %. Latino ethnicity, smoking 1-9 cigarettes/day at baseline, reporting smoke-free home, and additional educator contact in the year after the baseline were independent predictors of sustained cessation in the multivariate analysis. Smokers with multiple risks for poor cessation outcomes exposed to a guideline-based program of health education during routine healthcare encounters had sustained smoking cessation rates that compare favorably with published National Health Interview Study population cessation rates. An additional educator contact after the baseline was a predictor of cessation. The findings support development of cessation programs in which health educators are integrated into clinical care settings.

Validation of Self-reported Smoking with Urinary Cotinine Levels and Influence of Second-hand Smoke among Conscripts

Accurate identification of smoking behaviour is crucial to monitor the smoking rate. This study used urinary cotinine (UC) as a biomarker to verify the effectiveness of self-reported smoking behaviour among conscripts during recruit training. The influence of second-hand smoke (SHS) on the UC concentration was also analysed. A cross-sectional study was conducted from July 2014 to December 2014. The participants comprised a total of 621 military service and basic military training conscripts. A self-administered questionnaire survey and a urine test were performed to verify the participants’ smoking behaviour. The UC concentration of 100 ng/mL was adopted as the baseline to identify smokers. A high level of consistency was observed between the conscripts’ self-reported results and the results validated by the UC concentrations (the overall kappa coefficient was 0.918). Moreover, the overall sensitivity and specificity were 92.9% and 98.1%, respectively. The sensitivity for the military service conscripts was significantly lower than that for the basic military training conscripts (86.1% vs. 97.5%, P-value = 0.002). For the self-reported nonsmokers among the military service conscripts, SHS exposure was related to their UC concentrations. The method of self-reporting through a questionnaire survey can serve as a tool to assess conscripts’ smoking behaviour.

Feasibility of biochemical verification in a web-based smoking cessation study

BACKGROUND AND AIMS

Cogent arguments have been made against the need for biochemical verification in population-based studies with low-demand characteristics. Despite this fact, studies involving digital interventions (low-demand) are often required in peer review to report biochemically verified abstinence. To address this discrepancy, we examined the feasibility and costs of biochemical verification in a web-based study conducted with a national sample.

METHODS

Participants were 600U.S. adult current smokers who registered on a web-based smoking cessation program and completed surveys at baseline and 3months. Saliva sampling kits were sent to participants who reported 7-day abstinence at 3months, and analyzed for cotinine.

RESULTS

The response rate at 3-months was 41.2% (n=247): 93 participants reported 7-day abstinence (38%) and were mailed a saliva kit (71% returned). The discordance rate was 36.4%. Participants with discordant responses were more likely to report 3-month use of nicotine replacement therapy or e-cigarettes than those with concordant responses (79.2% vs. 45.2%, p=0.007). The total cost of saliva sampling was $8280 ($125/sample).

CONCLUSIONS

Biochemical verification was both time- and cost-intensive, and yielded a relatively small number of samples due to low response rates and use of other nicotine products during the follow-up period. There was a high rate of discordance of self-reported abstinence and saliva testing. Costs for data collection may be prohibitive for studies with large sample sizes or limited budgets. Our findings echo previous statements that biochemical verification is not necessary in population-based studies, and add evidence specific to technology-based studies.

Accuracy and utility of an epigenetic biomarker for smoking in populations with varying rates of false self-report

Better biomarkers to detect smoking are needed given the tremendous public health burden caused by smoking. Current biomarkers to detect smoking have significant limitations, notably a short half-life for detection and lack of sensitivity for light smokers. These limitations may be particularly problematic in populations with less accurate self-reporting. Prior epigenome-wide association studies indicate that methylation status at cg05575921, a CpG residue located in the aryl hydrocarbon receptor repressor (AHRR) gene, may be a robust indicator of smoking status in individuals with as little as half of a pack-year of smoking. In this study, we show that a novel droplet digital PCR assay for measuring methylation at cg05575921 can reliably detect smoking status, as confirmed by serum cotinine, in populations with different demographic characteristics, smoking histories, and rates of false-negative self-report of smoking behavior. Using logistic regression models, we show that obtaining maximum accuracy in predicting smoking status depends on appropriately weighting self-report and cg05575921 methylation according to the characteristics of the sample being tested. Furthermore, models using only cg05575921 methylation to predict smoking perform nearly as well as those also including self-report across populations. In conclusion, cg05575921 has significant potential as a clinical biomarker to detect smoking in populations with varying rates of accuracy in self-report of smoking behavior.

The Impact of Smoking on Sentinel Node Metastasis of Primary Cutaneous Melanoma

BACKGROUND

Although a well-established causative relationship exists between smoking and several epithelial cancers, the association of smoking with metastatic progression in melanoma is not well studied. We hypothesized that smokers would be at increased risk for melanoma metastasis as assessed by sentinel lymph node (SLN) biopsy.

METHODS

Data from the first international Multicenter Selective Lymphadenectomy Trial (MSLT-I) and the screening-phase of the second trial (MSLT-II) were analyzed to determine the association of smoking with clinicopathologic variables and SLN metastasis.

RESULTS

Current smoking was strongly associated with SLN metastasis (p = 0.004), even after adjusting for other predictors of metastasis. Among 4231 patients (1025 in MSLT-I and 3206 in MSLT-II), current or former smoking was also independently associated with ulceration (p < 0.001 and p < 0.001, respectively). Compared with current smoking, never smoking was independently associated with decreased Breslow thickness in multivariate analysis (p = 0.002) and with a 0.25 mm predicted decrease in thickness.

CONCLUSION

The direct correlation between current smoking and SLN metastasis of primary cutaneous melanoma was independent of its correlation with tumor thickness and ulceration. Smoking cessation should be strongly encouraged among patients with or at risk for melanoma.

Self-Reporting of Smoking Cessation in Cardiac Patients: How Reliable Is It and Is Reliability Associated With Patient Characteristics?

OBJECTIVES

The objectives of this study were to determine the accuracy of smoking cessation self-reports by cardiac patients who participated in a smoking cessation program, and to determine which patient characteristics are associated with an inaccurate self-report during a follow-up interview 12 months after the start of the program.

METHODS

Smoking cessation self-reports (point prevalence abstinence) were validated against salivary cotinine levels. Using χ analyses, patients who reported accurately being a nonsmoker were compared with those who reported inaccurately being a nonsmoker (biochemically verified as smokers) on factors the literature has indicated to be associated with inaccurate self-report in smoking. Potential predictors of inaccurate self-report of smoking (P ≤ 0.20 in univariate analyses) were subsequently tested in a multivariate logistic regression analysis.

RESULTS

Of the 95 patients tested, almost 25% inaccurately reported having quit smoking at a cutoff of 10-ng/mL cotinine in saliva. The data show more underreporting of smoking among patients who received a face-to-face counseling intervention and among patients with an intermediate education level. There was significantly less underreporting among patients characterized as having a Type D personality.

CONCLUSIONS

These findings suggest that underreporting of smoking status in cardiac patients who participate in a smoking cessation program is high, especially in those who receive intensive face-to-face counseling. Having a Type D personality seems to be a protective factor, whereas having an intermediate level of education is a risk factor for inaccurate reporting. Biochemical validation in high-risk populations is highly needed, ideally accompanied by alternative forms of verification. Optimal validation testing in smoking cessation studies of cardiac patients is difficult because of high refusal rates, no-show, and organizational difficulties.

Reversion of AHRR Demethylation Is a Quantitative Biomarker of Smoking Cessation

Smoking is the largest preventable cause of morbidity and mortality in the world. Although there are effective pharmacologic and behavioral treatments for smoking cessation, our inability to objectively quantify smokers' progress in decreasing smoking has been a barrier to both clinical and research efforts. In prior work, we and others have shown that DNA methylation at cg05575921, a CpG residue in the aryl hydrocarbon receptor repressor (AHRR), can be used to determine smoking status and infer cigarette consumption history. In this study, we serially assessed self-report and existing objective markers of cigarette consumption in 35 subjects undergoing smoking cessation therapy, then quantified DNA methylation at cg05575921 at study entry and three subsequent time points. Five subjects who reported serum cotinine and exhaled carbon monoxide verified smoking abstinence for the 3 months prior to study exit averaged a 5.9% increase in DNA methylation at cg05575921 (p < 0.004) over the 6-month study. Although the other 30 subjects did not achieve smoking cessation at the 6-month time point, their self-reported reduction of cigarette consumption (mean = 6 cigarettes/day) was associated with a 2.8% increase DNA methylation at cg05575921 (p < 0.05). Finally, a survey of subjects as they exited the study demonstrated strong support for the clinical use of epigenetic biomarkers. We conclude that AHRR methylation status is a quantifiable biomarker for progress in smoking cessation that could have substantial impact on both smoking cessation treatment and research.

Validation of Non-Smoking Status by Spouse Following a Cessation Intervention

BACKGROUND

Following cessation interventions, self-reported smoking abstinence with biochemical verification is the "gold standard" for defining outcomes. Because obtaining biochemical verification is challenging in community studies, we compared self-reported cessation among smokers completing treatment to the smoking status reported by each participant's spouse or proxy.

METHOD

Participants were smokers who had reported quitting 12 months after a cessation intervention. Participants had either attended a smoking cessation clinic or they were patients seen by physicians who had recently participated in a cessation-training program. Proxies living with these participants were interviewed by telephone to ask about their partner's smoking status. We compared the participants' responses to those from their spouses.

RESULTS

At 12 months, 346 of 1423 baseline smokers had quit; 161/346 reported non-smokers were called and 140 proxies were interviewed. The participants averaged 51 years of age, 69% were women. At baseline, the mean number of cigarettes smoked per day was 20.1 (SD = 9.9) and the average number of quit attempts was 2.4 (SD = 1.2). Cessation methods used were medical advice (21%) and/or pharmacotherapy (79%). Of the 140 spouses interviewed, only 10 (7.1%) reported that their partners were currently smoking.

CONCLUSIONS

Proxy-reported data on smoking status could be used to validate self-report.

A pilot randomized controlled trial of smoking cessation in an outpatient respirology clinic

OBJECTIVE

To assess the feasibility and potential effectiveness of a modified version of the Ottawa Model for Smoking Cessation in an outpatient respirology clinic.

METHODS

Adult tobacco smokers attending the respirology clinic and willing to choose a quit date within one month of enrollment were randomly assigned to receive standard care or the intervention. Standard care participants received smoking cessation advice, a brochure and a prescription for smoking cessation medication if requested. Intervention participants received a $110 voucher to purchase smoking cessation pharmacotherapy and were registered to an automated calling system. Answers to automated calls determined which participants required nurse telephone counselling. Feasibility indicators included recruitment and retention rates, and intervention adherence. The effectiveness indicator was self-reported smoking status at 26 to 52 weeks.

RESULTS

Forty-nine (54.4%) of 90 eligible smokers were randomly assigned to the intervention (n=23) or control (n=26) group. Self-reported smoking status at 26 to 52 weeks was available for 32 (65.3%) participants. The quit rate for intervention participants was 18.2% compared with 7.7% for controls (OR2.36 [95% CI 0.39 to 14.15]).

CONCLUSION

It would be feasible to evaluate this intervention in a larger trial. Alternatives to face-to-face follow-up at the clinic are recommended.