Assessing smoking status in children, adolescents and adults: cotinine cut-points revisited

Reaching Youth Smokers Through a Multipronged Approach: Comparison of Three Recruitment Methods of a Youth Quitline in Hong Kong

PURPOSE

Using multipronged recruitment strategies is crucial for reaching diverse smokers, yet research specifically focusing on youths is lacking. This prospective study compared the characteristics and abstinence outcomes of youth smokers enrolled in a youth-centered cessation service by three different methods.

METHODS

From December 2016 to February 2022, the Youth Quitline enrolled 1,197 smokers aged 10-25 (mean = 19.4) years through traditional method (incoming calls or referrals, n = 276), proactive outreach (n = 735), and online method (website or social media platforms, n = 186). Logistic regression was used to calculate the odds ratio (OR) of biochemically validated tobacco abstinence at 6 months by recruitment methods.

RESULTS

Proportionally more participants recruited via online method than traditional method and outreach had moderate to heavy nicotine dependence (53.2% vs. 40.9% vs. 27.6%, p < .001), poor self-rated health (27.6% vs. 21.9% vs. 12.3%, p < .001), and risk of depression (51.4% vs. 42.5% vs. 37.4%, p = .003). More participants recruited by outreach (71.6%) had no intention to quit in 30 days than traditional (58.3%) and online (59.7%) methods (p < .001). Compared with traditional method, the 6-month validated abstinence rate was similar in smokers recruited by online method (crude OR 0.77, 95% confidence interval 0.44-1.34) but significantly lower in those recruited by outreach (crude OR 0.44, 95% confidence interval 0.28-0.67). Results were similar after adjusting for sociodemographic and baseline predictors of abstinence.

DISCUSSION

Online recruitment can attract youth smokers with greater nicotine dependence and poorer health, whereas outreach can engage those with less motivation to quit. The lower quit rate in outreach-recruited participants indicated the need for more effective interventions.

Comparing the Effectiveness of the Blended Delivery Mode With the Face-to-Face Delivery Mode of Smoking Cessation Treatment: Noninferiority Randomized Controlled Trial

BACKGROUND

Tobacco consumption is a leading cause of death and disease, killing >8 million people each year. Smoking cessation significantly reduces the risk of developing smoking-related diseases. Although combined treatment for addiction is promising, evidence of its effectiveness is still emerging. Currently, there is no published research comparing the effectiveness of blended smoking cessation treatments (BSCTs) with face-to-face (F2F) treatments, where web-based components replace 50% of the F2F components in blended treatment.

OBJECTIVE

The primary objective of this 2-arm noninferiority randomized controlled trial was to determine whether a BSCT is noninferior to an F2F treatment with identical ingredients in achieving abstinence rates.

METHODS

This study included 344 individuals who smoke (at least 1 cigarette per day) attending an outpatient smoking cessation clinic in the Netherlands. The participants received either a blended 50% F2F and 50% web-based BSCT or only F2F treatment with similar content and intensity. The primary outcome measure was cotinine-validated abstinence rates from all smoking products at 3 and 15 months after treatment initiation. Additional measures included carbon monoxide-validated point prevalence abstinence; self-reported point prevalence abstinence; and self-reported continuous abstinence rates at 3, 6, 9, and 15 months after treatment initiation.

RESULTS

None of the 13 outcomes showed statistically confirmed noninferiority of the BSCT, whereas 4 outcomes showed significantly (P<.001) inferior abstinence rates of the BSCT: cotinine-validated point prevalence abstinence rate at 3 months (difference 12.7, 95% CI 6.2-19.4), self-reported point prevalence abstinence rate at 6 months (difference 19.3, 95% CI 11.5-27.0) and at 15 months (difference 11.7, 95% CI 5.8-17.9), and self-reported continuous abstinence rate at 6 months (difference 13.8, 95% CI 6.8-20.8). The remaining 9 outcomes, including the cotinine-validated point prevalence abstinence rate at 15 months, were inconclusive.

CONCLUSIONS

In this high-intensity outpatient smoking cessation trial, the blended mode was predominantly less effective than the traditional F2F mode. The results contradict the widely assumed potential benefits of blended treatment and suggest that further research is needed to identify the critical factors in the design of blended interventions.

TRIAL REGISTRATION

Netherlands Trial Register 27150; https://onderzoekmetmensen.nl/nl/trial/27150.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-doi.org/10.1186/s12889-016-3851-x.

Inequality in uptake of bowel cancer screening by deprivation, ethnicity and smoking status: cross-sectional study in 86 850 citizens

BACKGROUND

Survival from colorectal cancer depends on stage at detection. In England, bowel cancer mortality has historically been highest in deprived areas. During the initial stages of the COVID-19 pandemic, it was necessary to temporarily halt many screening programmes, which may have led to inequalities in uptake since screening restarted.

METHODS

Cross-sectional data from the Bristol, North Somerset and South Gloucestershire Systemwide Dataset were analyzed. Associations of baseline characteristics with uptake of bowel screening were examined using logistic regression.

RESULTS

Amongst 86 850 eligible adults aged 60-74 years, 5261 had no screening record. There was little evidence of association between no screening and sex (adjusted odds ratio 0.95 (95% confidence interval 0.90, 1.02)). Absence of screening record was associated with deprivation (1.26 (1.14, 1.40) for the most compared with the least deprived groups), smoking (1.11 (1.04, 1.18)) compared with no smoking record and black (1.36 (1.09, 1.70)) and mixed (1.08 (1.01, 1.15)) ethnicity compared with white ethnicity.

CONCLUSIONS

In a data set covering a whole NHS Integrated Care Board, there was evidence of lower uptake of bowel cancer screening in adults living in more deprived areas, of minority ethnic groups and who smoked. These findings may help focus community engagement work and inform research aimed at reducing inequalities.

Efficacy of a Smoking Cessation Intervention for Survivors of Cervical Intraepithelial Neoplasia or Cervical Cancer: A Randomized Controlled Trial

PURPOSE

Women who smoke and have a history of cervical intraepithelial neoplasia (CIN) or cervical cancer represent a vulnerable subgroup at elevated risk for recurrence, poorer cancer treatment outcomes, and decreased quality of life. The purpose of this study was to evaluate the long-term efficacy of Motivation And Problem Solving (MAPS), a novel treatment well-suited to meeting the smoking cessation needs of this population.

METHODS

Women who were with a history of CIN or cervical cancer, age 18 years and older, spoke English or Spanish, and reported current smoking (≥100 lifetime cigarettes plus any smoking in the past 30 days) were eligible. Participants (N = 202) were recruited in clinic in Oklahoma City and online nationally and randomly assigned to (1) standard treatment (ST) or (2) MAPS. ST consisted of repeated referrals to a tobacco cessation quitline, self-help materials, and combination nicotine replacement therapy (patch plus lozenge). MAPS comprised all ST components plus up to six proactive telephone counseling sessions over 12 months. Logistic regression and generalized estimating equations evaluated the intervention. The primary outcome was self-reported 7-day point prevalence abstinence from tobacco at 18 months, with abstinence at 3, 6, and 12 months and biochemically confirmed abstinence as secondary outcomes.

RESULTS

There was no significant effect for MAPS over ST at 18 months (14.2% v 12.9%, P = .79). However, there was a significant condition × assessment interaction (P = .015). Follow-up analyses found that MAPS (v ST) abstinence rates were significantly greater at 12 months (26.4% v 11.9%, P = .017; estimated OR, 2.60; 95% CI, 1.19 to 5.89).

CONCLUSION

MAPS led to a greater than two-fold increase in smoking abstinence among survivors of CIN and cervical cancer at 12 months. At 18 months, abstinence in MAPS declined to match the control condition and the treatment effect was no longer significant.

Motivational support intervention to reduce smoking and increase physical activity in smokers not ready to quit: the TARS RCT

Background

Physical activity can support smoking cessation for smokers wanting to quit, but there have been no studies on supporting smokers wanting only to reduce. More broadly, the effect of motivational support for such smokers is unclear.

Objectives

The objectives were to determine if motivational support to increase physical activity and reduce smoking for smokers not wanting to immediately quit helps reduce smoking and increase abstinence and physical activity, and to determine if this intervention is cost-effective.

Design

This was a multicentred, two-arm, parallel-group, randomised (1 : 1) controlled superiority trial with accompanying trial-based and model-based economic evaluations, and a process evaluation.

Setting and participants

Participants from health and other community settings in four English cities received either the intervention (n = 457) or usual support (n = 458).

Intervention

The intervention consisted of up to eight face-to-face or telephone behavioural support sessions to reduce smoking and increase physical activity.

Main outcome measures

The main outcome measures were carbon monoxide-verified 6- and 12-month floating prolonged abstinence (primary outcome), self-reported number of cigarettes smoked per day, number of quit attempts and carbon monoxide-verified abstinence at 3 and 9 months. Furthermore, self-reported (3 and 9 months) and accelerometer-recorded (3 months) physical activity data were gathered. Process items, intervention costs and cost-effectiveness were also assessed.

Results

The average age of the sample was 49.8 years, and participants were predominantly from areas with socioeconomic deprivation and were moderately heavy smokers. The intervention was delivered with good fidelity. Few participants achieved carbon monoxide-verified 6-month prolonged abstinence [nine (2.0%) in the intervention group and four (0.9%) in the control group; adjusted odds ratio 2.30 (95% confidence interval 0.70 to 7.56)] or 12-month prolonged abstinence [six (1.3%) in the intervention group and one (0.2%) in the control group; adjusted odds ratio 6.33 (95% confidence interval 0.76 to 53.10)]. At 3 months, the intervention participants smoked fewer cigarettes than the control participants (21.1 vs. 26.8 per day). Intervention participants were more likely to reduce cigarettes by ≥ 50% by 3 months [18.9% vs. 10.5%; adjusted odds ratio 1.98 (95% confidence interval 1.35 to 2.90] and 9 months [14.4% vs. 10.0%; adjusted odds ratio 1.52 (95% confidence interval 1.01 to 2.29)], and reported more moderate-to-vigorous physical activity at 3 months [adjusted weekly mean difference of 81.61 minutes (95% confidence interval 28.75 to 134.47 minutes)], but not at 9 months. Increased physical activity did not mediate intervention effects on smoking. The intervention positively influenced most smoking and physical activity beliefs, with some intervention effects mediating changes in smoking and physical activity outcomes. The average intervention cost was estimated to be £239.18 per person, with an overall additional cost of £173.50 (95% confidence interval -£353.82 to £513.77) when considering intervention and health-care costs. The 1.1% absolute between-group difference in carbon monoxide-verified 6-month prolonged abstinence provided a small gain in lifetime quality-adjusted life-years (0.006), and a minimal saving in lifetime health-care costs (net saving £236).

Conclusions

There was no evidence that behavioural support for smoking reduction and increased physical activity led to meaningful increases in prolonged abstinence among smokers with no immediate plans to quit smoking. The intervention is not cost-effective.

Limitations

Prolonged abstinence rates were much lower than expected, meaning that the trial was underpowered to provide confidence that the intervention doubled prolonged abstinence.

Future work

Further research should explore the effects of the present intervention to support smokers who want to reduce prior to quitting, and/or extend the support available for prolonged reduction and abstinence.

Trial registration

This trial is registered as ISRCTN47776579.

Funding

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 4. See the NIHR Journals Library website for further project information.

β-Cryptoxanthin Attenuates Cigarette-Smoke-Induced Lung Lesions in the Absence of Carotenoid Cleavage Enzymes (BCO1/BCO2) in Mice

High dietary intake of β-cryptoxanthin (BCX, an oxygenated provitamin A carotenoid) is associated with a lower risk of lung disease in smokers. BCX can be cleaved by β-carotene-15,15'-oxygenase (BCO1) and β-carotene-9',10'-oxygenase (BCO2) to produce retinol and apo-10'-carotenoids. We investigated whether BCX has protective effects against cigarette smoke (CS)-induced lung injury, dependent or independent of BCO1/BCO2 and their metabolites. Both BCO1^-/-/BCO2^-/- double knockout mice (DKO) and wild type (WT) littermates were supplemented with BCX 14 days and then exposed to CS for an additional 14 days. CS exposure significantly induced macrophage and neutrophil infiltration in the lung tissues of mice, regardless of genotypes, compared to the non-exposed littermates. BCX treatment significantly inhibited CS-induced inflammatory cell infiltration, hyperplasia in the bronchial epithelium, and enlarged alveolar airspaces in both WT and DKO mice, regardless of sex. The protective effects of BCX were associated with lower expression of IL-6, TNF-α, and matrix metalloproteinases-2 and -9. BCX treatment led to a significant increase in hepatic BCX levels in DKO mice, but not in WT mice, which had significant increase in hepatic retinol concentration. No apo-10'-carotenoids were detected in any of the groups. In vitro BCX, at comparable doses of 3-OH-β-apo-10'-carotenal, was effective at inhibiting the lipopolysaccharide-induced inflammatory response in a human bronchial epithelial cell line. These data indicate that BCX can serve as an effective protective agent against CS-induced lung lesions in the absence of carotenoid cleavage enzymes.

Prolonged, physiologically relevant nicotine concentrations in the airways of smokers

Nicotine from cigarette smoke is a biologically active molecule that has pleiotropic effects in the airway, which could play a role in smoking-induced lung disease. However, whether nicotine and its metabolites reach sustained, physiologically relevant concentrations on airway surfaces of smokers is not well defined. To address these issues, concentrations of nicotine, cotinine, and hydroxycotinine were measured by mass spectrometry (MS) in supernatants of induced sputum obtained from participants in the subpopulations and intermediate outcome measures in COPD study (SPIROMICS), an ongoing observational study that included never smokers, former smokers, and current smokers with and without chronic obstructive pulmonary disease (COPD). A total of 980 sputum supernatants were analyzed from 77 healthy never smokers, 494 former smokers (233 with COPD), and 396 active smokers (151 with COPD). Sputum nicotine, cotinine, and hydroxycotinine concentrations corresponded to self-reported smoking status and were strongly correlated to urine measures. A cutoff of ∼8-10 ng/mL of sputum cotinine distinguished never smokers from active smokers. Accounting for sample dilution during processing, active smokers had airway nicotine concentrations in the 70-850 ng/mL (∼0.5-5 µM) range, and concentrations remained elevated even in current smokers who had not smoked within 24 h. This study demonstrates that airway nicotine and its metabolites are readily measured in sputum supernatants and can serve as biological markers of smoke exposure. In current smokers, nicotine is present at physiologically relevant concentrations for prolonged periods, supporting a contribution to cigarette-induced airway disease.

Optimum Urine Cotinine and NNAL Levels to Distinguish Smokers from Non-Smokers by the Changes in Tobacco Control Policy in Korea from 2008 to 2018

INTRODUCTION

We examined the age- and sex-specific distributions of biomarkers of tobacco smoke exposure to determine the optimal cutoffs to distinguish smokers from non-smokers over the last 10 years in Korea, during which smoking prevalence and secondhand smoke (SHS) exposure declined due to changes in tobacco control policy.

METHODS

We analyzed data from the Korea National Health and Nutrition Examination Survey on creatinine-adjusted urinary cotinine (2008-2018; 33 429 adults: 15 653 males and 17 776 females) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL; 2016-2018; 6337 adults: 3091 males and 3246 females). We determined the optimal cutoffs and confidence intervals (CIs) to distinguish smokers from non-smokers using receiver operator characteristic curve analysis and bootstrapping (1000 resamples).

RESULTS

The optimal cutoff values of creatinine-adjusted urine cotinine and NNAL concentration were 20.9 ng/mg (95% CI: 20.8-21.0, sensitivity: 96.6%, specificity: 93.8%) and 8.9 pg/mg (95% CI: 8.8-8.9, sensitivity: 94.0%, specificity: 94.7%), respectively, in 2016-2018. The optimal cutoffs of both biomarkers increased with age and were higher in females than in males for NNAL concentration. In both sexes, the optimal cutoff of urine cotinine continuously declined over the study period.

CONCLUSIONS

The optimal cotinine cutoff declined along with smoking prevalence and levels of SHS exposure due to enforcement of tobacco control policies, including smoke-free ordinances and tax increases. Monitoring of biomarkers of tobacco exposure appears necessary for verification of smoking status and regulatory use.

IMPLICATIONS

Our results based on nationally representative data suggest that a large decrease in the optimal cutoff value of urine cotinine to distinguish smokers from non-smokers was caused by decreases in smoking prevalence and SHS exposure following enforcement of tobacco control policies over the last 10 years. We determined the optimal cutoff values of urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which were not previously reported in representative population in Asia, to enable more accurate estimation of exposure to tobacco smoke and proper assessment of disease risks. Gender- and age-specific differences in the optimal cutoffs require further study. Monitoring of biomarkers of tobacco smoke exposure seems necessary for verification of smoking status and regulatory use.

Changes in the salivary cotinine cut-offs to discriminate smokers and non-smokers before and after Spanish smoke-free legislation

INTRODUCTION

High levels of cotinine in non-smokers indicate passive exposure to tobacco smoke. This study aims to evaluate variations in salivary cotinine cut-offs to discriminate smokers and non-smokers before and after the implementation of smoke-free legislation (Law 28/2005 and Law 42/2010) in a sample of the adult population of Barcelona, Spain.

METHODS

This longitudinal study analyzes salivary cotinine samples and self-reported information from a representative sample (n = 676) of the adult population from Barcelona before and after the approval of smoke-free legislation. We calculated the receiver operating characteristic (ROC) curves, to obtain optimal cotinine cut-off points to discriminate between smokers and non-smokers overall, by sex and age, and their corresponding sensitivity, specificity, and area under the curve. We used linear mixed-effects models, with individuals as random effects, to model the percentage change of cotinine concentration before and after the implementation of both laws.

RESULTS

The mean salivary cotinine concentration was significantly lower post-2010 law (-85.8%, p < 0.001). The ROC curves determined that the optimal cotinine cut-off points for discriminating non-smokers and smokers were 10.8 ng/mL (pre-2005 law) and 5.6 ng/mL (post-2010 law), with a post-2010 law sensitivity of 92.6%, specificity of 98.4%, and an area under the curve of 97.0%. The post-2010 law cotinine cut-off points were 5.6 ng/mL for males and 1.9 ng/mL for females.

CONCLUSION

The implementation of Spanish smoke-free legislation was effective in reducing secondhand smoke exposure and, therefore, also in reducing the cut-off point for salivary cotinine concentration. This value should be used to better assess tobacco smoke exposure in this population.

Using the biomarker cotinine and survey self-report to validate smoking data from United States Veterans Health Administration electronic health records

Objective

Tobacco use/smoking for epidemiologic studies is often derived from electronic health record (EHR) data, which may be inaccurate. We previously compared smoking from the United States Veterans Health Administration (VHA) EHR clinical reminder data with survey data and found excellent agreement. However, the smoking clinical reminder items changed October 1, 2018. We sought to use the biomarker salivary cotinine (cotinine ≥30) to validate current smoking from multiple sources.

Materials and Methods

We included 323 Veterans Aging Cohort Study participants with cotinine, clinical reminder, and self-administered survey smoking data from October 1, 2018 to September 30, 2019. We included International Classification of Disease (ICD)-10 codes F17.21 and Z72.0. Operating characteristics and kappa statistics were calculated.

Results

Participants were mostly male (96%), African American (75%) and mean age was 63 years. Of those identified as currently smoking based on cotinine, 86%, 85%, and 51% were identified as currently smoking based on clinical reminder, survey, and ICD-10 codes, respectively. Of those identified as not currently smoking based on cotinine, 95%, 97%, and 97% were identified as not currently smoking based on clinical reminder, survey, and ICD-10 codes. Agreement with cotinine was substantial for clinical reminder (kappa = .81) and survey (kappa = .83), but only moderate for ICD-10 (kappa = .50).

Discussion

To determine current smoking, clinical reminder, and survey agreed well with cotinine, whereas ICD-10 codes did not. Clinical reminders could be used in other health systems to capture more accurate smoking information.

Conclusions

Clinical reminders are an excellent source for self-reported smoking status and are readily available in the VHA EHR.

Serum cotinine cut-points for secondhand smoke exposure assessment in children under 5 years: A systemic review

Background

Serum cotinine has become the most widely used biomarker of secondhand smoke exposure (SHS) over time in all ages. The aim of this study was to review the serum cotinine cut-points used to classify children under 5 years as exposed to SHS.

Methods

A systematic review performed in the Pubmed (MEDLINE) and EMBASE databases up to April 2021 was conducted using as key words "serum cotinine", “tobacco smoke pollution” (MeSH), "secondhand smoke", "environmental tobacco smoke" and “tobacco smoke exposure”. Papers which assessed SHS exposure among children younger than 5 years old were included. The PRISMA 2020 guidelines were followed. Analysis was pre-registered in PROSPERO (registration number: CRD42021251263).

Results

247 articles were identified and 51 fulfilled inclusion criteria. The selected studies were published between 1985–2020. Most of them included adolescents and adults. Only three assessed postnatal exposure exclusively among children under 5 years. None of the selected studies proposed age-specific cut-points for children < 5 years old. Cut-point values to assess SHS exposure ranged from 0.015 to 100 ng/ml. The most commonly used cut-point was 0.05 ng/ml, derived from the assay limit of detection used by the National Health and Nutrition Examination Survey (NHANES).

Conclusions

No studies have calculated serum cotinine age-specific cut-points to ascertained SHS exposure among children under 5 years old. Children’s age-specific cut-points are warranted for health research and public health purposes aimed at accurately estimating the prevalence of SHS exposure and attributable burden of disease to such exposure, and at reinforcing 100% smoke-free policies worldwide, both in homes, private vehicles and public places.

Association between Diet Quality and Adolescent Wheezing: Effect Modification by Environmental Tobacco Smoke Exposure

RATIONALE

Protective effects of a high quality diet on respiratory health, particularly among youths exposed to environmental tobacco smoke (ETS), are unknown.

OBJECTIVES

To assess if a higher quality diet is associated with improved respiratory symptoms and lung function among adolescents, and if these associations are modified by ETS exposure.

METHODS

This was a cross-sectional study on 7,026 nonsmoking adolescents of the 2003-2012 National Health and Nutrition Examination Survey. Diet quality was assessed using the Healthy Eating Index-2010 score (HEI-2010), categorized into quintiles. ETS exposure was measured using serum cotinine, dichotomized as high (>2.99 ng/ml) or low (≤2.99 ng/ml). Outcomes included the presence of wheezing and cough symptoms in the past 12 months, and in a sub-group, spirometric lung function. Survey-design adjusted logistic and linear models evaluated associations between diet and 1) respiratory symptoms and 2) lung function, respectively, and assessed the interaction between HEI-2010 and serum cotinine.

RESULTS

While there were no significant associations between diet quality and respiratory symptoms, there was a significant interaction between HEI-2010 and serum cotinine on wheezing (pint = 0.011). In models stratified by serum cotinine, adolescents with high serum cotinine and the healthiest diet (5th quintile HEI-2010) experienced lower wheezing odds (OR, 0.10; 95% CI, 0.02-0.61), compared to those with the poorest diet (1st quintile HEI-2010). In contrast, among adolescents with low serum cotinine, there were no significant differences in any respiratory symptoms between those with the highest, compared to the lowest diet quality. Of the sub-group with spirometry data (n = 3,166), there was a trend towards better lung function with improving diet quality, although this did not achieve statistical significance. There was no effect modification by ETS exposure on the relationship between diet quality and lung function.

CONCLUSIONS

Consuming a higher quality diet was associated with lower wheezing odds in adolescents with substantial ETS exposure. While longitudinal studies are needed, public health interventions to improve diet quality in vulnerable, environmentally-exposed populations merit consideration.

Estimating the equity impacts of the smoking ban in England on cotinine levels: a regression discontinuity design

OBJECTIVE

To estimate the equity impacts of the 2007 smoking ban in England, for both smokers and non-smokers.

DESIGN

Doubly robust regression discontinuity analysis of salivary cotinine levels. Conditional average treatment effects were used to estimate differential impacts of the ban by socioeconomic deprivation (based on the Index of Multiple Deprivation). Distributional impacts were further assessed using conditional quantile treatment effects and inequality treatment effects.

SETTING

In 2007, England introduced a ban on smoking in public places. This had little impact on tobacco consumption by smokers but was associated with decreases in environmental tobacco smoke exposure for non-smokers. However, the impact of the ban on socioeconomic inequalities in exposure is unclear.

PARTICIPANTS

766 smokers and 2952 non-smokers responding to the Health Survey for England in 2007.

OUTCOME MEASURE

Levels of salivary cotinine.

RESULTS

Before the ban, socioeconomic deprivation was associated with higher cotinine levels for non-smokers but not for smokers. The ban caused a significant reduction in average cotinine levels for non-smokers (p=0.043) but had no effect for smokers (p=0.817). Reductions for non-smokers were greater for more deprived groups with higher levels of exposure, and there was a significant reduction in socioeconomic-related inequality in cotinine. Across the whole population (both smokers and non-smokers), there was no significant increase in the concentration of cotinine levels among the socioeconomically deprived.

CONCLUSION

The 2007 ban on smoking in public places had little impact on smokers, but was, as intended, associated with reductions in both (1) average levels of environmental tobacco smoke exposure and (2) deprivation-related inequality in exposure among non-smokers.

Implementation of Ask-Advise-Connect in a safety net healthcare system: quitline treatment engagement and smoking cessation outcomes

Ask-Advise-Connect (AAC) was designed to link smokers in primary care settings with evidence-based tobacco treatment delivered via state quitlines. AAC involves training medical staff to Ask about smoking status, Advise smokers to quit, and offer to immediately Connect smokers with quitlines through an automated link within the electronic health record. We evaluated the efficacy of AAC in facilitating treatment engagement and smoking abstinence in a 34 month implementation trial conducted in a large, safety-net health care system. AAC was implemented from April 2013 through February 2016 in 13 community clinics that provided care to low-income, predominantly racial/ethnic minority smokers. Licensed vocational nurses were trained to implement AAC as part of standard care. Outcomes included (a) treatment engagement (i.e., proportion of identified smokers that enrolled in treatment) and (b) self-reported and biochemically confirmed abstinence at 6 months. Smoking status was recorded for 218,915 unique patients, and 40,888 reported current smoking. The proportion of all identified smokers who enrolled in treatment was 11.8%. Self-reported abstinence at 6 months was 16.6%, and biochemically confirmed abstinence was 4.5%. AAC was successfully implemented as part of standard care. Treatment engagement was high compared with rates of engagement for more traditional referral-based approaches reported in the literature. Although self-reported abstinence was in line with other quitline-delivered treatment studies, biochemically confirmed abstinence, which is not routinely captured in quitline studies, was dramatically lower. This discrepancy challenges the adequacy of self-report for large, population-based studies. A more detailed and comprehensive investigation is warranted.

Prevalence and trends in tobacco use among adolescents aged 13-15 years in 143 countries, 1999-2018: findings from the Global Youth Tobacco Surveys

BACKGROUND

Tobacco use is a leading preventable cause of morbidity and mortality worldwide. Little is known about recent prevalence and trends in tobacco use among adolescents globally. We aimed to assess the recent global prevalence of tobacco use in young adolescents and the secular trends in prevalence between 1999 and 2018.

METHODS

We used the most recent Global Youth Tobacco Surveys data on adolescents aged 13-15 years from 143 countries or territories that had done at least one survey between Jan 1, 2010, and Dec 31, 2018, to assess the recent prevalence of tobacco use; and data from 140 countries that had done two or more surveys between Jan 1, 1999, and Dec 31, 2018, to assess the trends in the prevalence of tobacco use.

FINDINGS

530 234 adolescents were included from the 143 countries that had done at least one survey between 2010 and 2018. 1 192 312 adolescents were included from the 140 countries that had done two or more surveys between 1999 and 2018. The most recent global prevalence of cigarette smoking was 11·3% (95% CI 10·3-12·3) in boys and 6·1% (5·6-6·6) in girls, based on cigarette smoking on at least 1 day during the past 30 days, 6·0% (5·5-6·6) and 2·6% (2·4-2·9) based on smoking on at least 3 days, and 4·2% (3·8-4·6) and 1·6% (1·4-1·8) based on smoking on at least 6 days. The most recent prevalence of the use of tobacco products other than cigarettes (eg, chewing tobacco, snuff, dip, cigars, cigarillos, pipe, electronic cigarettes) on at least 1 day during the past 30 days was 11·2% (9·9-12·6) in boys and 7·0% (6·4-7·7) in girls. The most recent prevalence of any tobacco use on at least 1 day during the past 30 days was 17·9% (16·1-19·6) in boys and 11·5% (10·5-12·4) in girls. The prevalence of cigarette smoking on at least 1 day during the past 30 days decreased between the first and last surveys in 80 (57·1%) of 140 countries, was unchanged in 39 countries (27·9%), and increased in 21 countries (15·0%). However, the prevalence of the use of tobacco products other than cigarettes was unchanged or increased in 81 (59·1%) of 137 countries.

INTERPRETATION

The global prevalence of tobacco use among adolescents aged 13-15 years was substantial. Although the prevalence of cigarette smoking decreased over time in the majority of countries, the prevalence of the use of other tobacco products increased or did not change in the majority of countries during the past two decades. These findings re-emphasise the need to strengthen tobacco control efforts among young adolescents globally.

FUNDING

Shandong University.

Independent Associations Between Different Measures of Socioeconomic Position and Smoking Status: A Cross-Sectional Study of Adults in England

INTRODUCTION

To gain a better understanding of the complex and independent associations between different measures of socioeconomic position (SEP) and smoking in England.

AIMS AND METHODS

Between March 2013 and January 2019 data were collected from 120 496 adults aged 16+ in England taking part in the Smoking Toolkit Study. Of these, 18.04% (n = 21 720) were current smokers. Six indicators of SEP were measured: social grade, employment status, educational qualifications, home and car ownership and income. Models were constructed using ridge regression to assess the contribution of each measure of SEP, taking account of high collinearity.

RESULTS

The strongest predictor of smoking status was housing tenure. Those who did not own their own home had twice the odds of smoking compared with homeowners (odds ratio [OR] = 2.01). Social grade, educational qualification, and income were also good predictors. Those in social grades C1 (OR = 1.04), C2 (OR = 1.29), D (OR = 1.39), and E (OR = 1.78) had higher odds of smoking than those in social grade AB. Similarly, those with A-level/equivalent (OR = 1.15), GCSE/vocational (OR = 1.48), other/still studying (OR = 1.12), and no post-16 qualifications (OR = 1.48) had higher odds of smoking than those with university qualifications, as did those who earned in the lowest (OR = 1.23), third (OR = 1.18), and second quartiles (OR = 1.06) compared with those earning in the highest. Associations between smoking and employment (OR = 1.03) and car ownership (OR = 1.05) were much smaller.

CONCLUSIONS

Of a variety of socioeconomic measures, housing tenure appears to be the strongest independent predictor of smoking in England, followed by social grade, educational qualifications, and income. Employment status and car ownership have the lowest predictive power.

IMPLICATIONS

This study used ridge regression, a technique which takes into account high collinearity between variables, to gain a better understanding of the independent associations between different measures of SEP and smoking in England. The findings provide guidance as to which SEP measures one could use when trying to identifying individuals most at risk from smoking, with housing tenure identified as the strongest independent predictor.

Randomised controlled trial of tailored support to increase physical activity and reduce smoking in smokers not immediately ready to quit: protocol for the Trial of physical Activity-assisted Reduction of Smoking (TARS) Study

INTRODUCTION

Smoking reduction can lead to increased success in quitting. This study aims to determine if a client-focused motivational support package for smoking reduction (and quitting) and increasing (or otherwise using) physical activity (PA) can help smokers who do not wish to quit immediately to reduce the amount they smoke, and ultimately quit. This paper reports the study design and methods.

METHODS AND ANALYSIS

A pragmatic, multicentred, parallel, two group, randomised controlled superiority clinical trial, with embedded process evaluation and economics evaluation. Participants who wished to reduce smoking with no immediate plans to quit were randomised 1:1 to receive either (1) tailored individual health trainer face-to-face and/or telephone support to reduce smoking and increase PA as an aid to smoking reduction (intervention) or (2) brief written/electronic advice to reduce or quit smoking (control). Participants in both arms of the trial were also signposted to usual local support for smoking reduction and quitting. The primary outcome measure is 6-month carbon monoxide-confirmed floating prolonged abstinence following participant self-reported quitting on a mailed questionnaire at 3 and 9 months post-baseline. Participants confirmed as abstinent at 9 months will be followed up at 15 months.

ETHICS AND DISSEMINATION

Approved by SW Bristol National Health Service Research Committee (17/SW/0223). Dissemination will include publication of findings for the stated outcomes, parallel process evaluation and economic evaluation in peer-reviewed journals. Results will be disseminated to trial participants and healthcare providers.

TRIAL REGISTRATION NUMBER

ISRCTN47776579; Pre-results.

Whole body electronic cigarette exposure system for efficient evaluation of diverse inhalation conditions and products

Objectives: To develop and test a new system for whole body exposure of small animals to support investigation of the biological effects of aerosol generated by electronic cigarette (e-cig) products under diverse inhalation conditions with improved control and monitoring of the e-cig vape exposure and nicotine delivered to the animal's systemic circulation. Methods: A computer-controlled design, with built-in sensors for real time monitoring of O₂, CO₂, relative humidity, and temperature within the exposure chambers and port for measuring total particulate matter (TPM) was developed, constructed and tested. This design accommodates a variety of commercial vaping devices, offers software flexibility to adjust exposure protocols to mimic different users' puffing patterns, enables variable nicotine delivery to the animal's systemic circulation; minimizes travel time and alterations of aerosol quality or quantity by delivering aerosol directly to the exposure chamber, offers local or remote operation of up to six distinct exposure chambers from a single control unit, and can simultaneously test different exposure conditions or products in diverse animal groups, which reduces inter-run variability, saves time, and increases productivity. Results: The time course pattern of TPM concentration during different phases of the exposure cycle was measured. With increased puffing duration or number of exposure cycles, higher TPM exposure and plasma cotinine levels were observed with plasma cotinine levels in the range reported in light or heavy smokers. Conclusion: Overall, this novel, versatile, and durable exposure system facilitates high-throughput evaluation of the relative safety and potential toxicity of a variety of e-cig devices and liquids.

Biochemical Verification of Tobacco Use and Abstinence: 2019 Update

BACKGROUND

The changing prevalence and patterns of tobacco use, the advent of novel nicotine delivery devices, and the development of new biomarkers prompted an update of the 2002 Society for Research on Nicotine and Tobacco (SRNT) report on whether and how to apply biomarker verification for tobacco use and abstinence.

METHODS

The SRNT Treatment Research Network convened a group of investigators with expertise in tobacco biomarkers to update the recommendations of the 2002 SNRT Biochemical Verification Report.

RESULTS

Biochemical verification of tobacco use and abstinence increases scientific rigor and is recommended in clinical trials of smoking cessation, when feasible. Sources, appropriate biospecimens, cutpoints, time of detection windows and analytic methods for carbon monoxide, cotinine (including over the counter tests), total nicotine equivalents, minor tobacco alkaloids, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol are reviewed, as well as biochemical approaches to distinguishing cigarette smoking from use of electronic nicotine delivery devices (ENDS).

CONCLUSIONS

Recommendations are provided for whether and how to use biochemical verification of tobacco use and abstinence. Guidelines are provided on which biomarkers to use, which biospecimens to use, optimal cutpoints, time windows to detection, and methodology for biochemical verifications. Use of combinations of biomarkers is recommended for assessment of ENDS use.

IMPLICATIONS

Biochemical verification increases scientific rigor, but there are drawbacks that need to be assessed to determine whether the benefits of biochemical verification outweigh the costs, including the cost of the assays, the feasibility of sample collection, the ability to draw clear conclusions based on the duration of abstinence, and the variability of the assay within the study population. This paper provides updated recommendations from the 2002 SRNT report on whether and how to use biochemical markers in determining tobacco use and abstinence.

Investigating the added value of biomarkers compared with self-reported smoking in predicting future e-cigarette use: Evidence from a longitudinal UK cohort study

Biomarkers can be used to assess smoking behaviour more accurately and objectively than self-report. This study assessed the association between cotinine (a biomarker of smoke exposure) and later e-cigarette use among a population who were unexposed to e-cigarettes in youth. Young people in the Avon Longitudinal Study of Parents and Children took part in the study. We observed associations between cotinine at 15 years (measured between 2006 and 2008 before the wide availability of e-cigarettes) and self-reported ever use of e-cigarettes at 22 (measured between 2014 and 2015 when e-cigarettes were widely available) using logistic regression. A range of potential confounders were adjusted for (age, sex, body mass index, alcohol use and passive smoke exposure). Additionally, we adjusted for the young people's self-reported smoking status/history to explore potential misreporting and measurement error. In a sample of N = 1,194 young people, cotinine levels consistent with active smoking at 15 years were associated with increased odds of e-cigarette ever use at 22 years (Odds Ratio [OR] = 7.24, 95% CI 3.29 to 15.93) even when self-reported active smoking status at age 16 (OR = 3.14, 95% CI 1.32 to 7.48) and latent classes of smoking behaviour from 14 to 16 (OR = 2.70, 95% CI 0.98 to 7.44) were included in the model. Cotinine levels consistent with smoking in adolescence were strongly associated with increased odds of later e-cigarette use, even after adjusting for reported smoking behaviour at age 16 and smoking transitions from 14 to 16.

Self-reported smoking among adolescents: How accurate is it with the urine cotinine strip test?

BACKGROUND & OBJECTIVE

In the local setting, the prevalence of smoking among adolescents varies, as it is based only on self-reporting without biomarker validation. The objective of the present study was to determine the accuracy of self-reported smoking among adolescents as compared to that of the urine cotinine strip test.

METHODS

We performed a cross-sectional study of 314 adolescents aged 16 years from February 2015 to April 2015 in Putrajaya, Malaysia. The accuracy of self-reporting was assessed using a data collection sheet and was validated by the urine cotinine strip test. Three schools were chosen by the simple random method, where all Form 4 students constituted the sample unit. The kappa statistic was used for determining agreement between self-reporting and urine cotinine strip testing.

RESULTS

There was a substantial agreement between self-reporting and the urine cotinine strip test (kappa = 0.757, 95% confidence interval [CI]: 0.63, 0.88); there was 95.86% overall agreement. The prevalence of self-reported smoking was 8% (95% CI: 7.47, 8.53) and that of urine cotinine strip testing was 10.8% (95% CI: 10.20, 11.41). There was a discrepancy with the results of the urine cotinine strip test in 8% of self-reported smokers and 3.8% of self-reported nonsmokers. Self-reporting had 67.6% sensitivity and 99.3% specificity as compared to those of urine cotinine strip testing and had 92% positive predictive value and 96.2% negative predictive value.

CONCLUSION

Self-reporting can be used to assess smoking status but should be used with care among adolescents. Urine cotinine strip test validation of self-reporting enables the measurement of the true prevalence of smoking among adolescents.

Magnitude and Chronicity of Environmental Smoke Exposure Across Infancy and Early Childhood in a Sample of Low-Income Children

INTRODUCTION

Infants and young children may be at an increased risk for second- and thirdhand exposure to tobacco smoke because of increased respiration rate and exposure to surface residue. However, relatively fewer studies have examined biomarkers of exposure (cotinine) in children under age 4 years. This study examines the magnitude and chronicity of exposure across early childhood among children from low-income families in order to better characterize contextual risk factors associated with exposure.

METHODS

A total of 1292 families were recruited in six nonurban counties of Pennsylvania and North Carolina. Cotinine was assayed from infant saliva at 6, 15, 24, and 48 months of age (N = 1218), and categorized as low (≤0.45 ng/mL), moderate (0.46-12 ng/mL), or high (≥12 ng/mL) at each time point. Categories were highly correlated across time. Latent class analysis was used to summarize patterns of exposure categories across time.

RESULTS

Magnitude of exposure in this sample was high, with approximately 12% of infants registering cotinine values at least 12 ng/mL, consistent with active smoking in adults. Greater exposure was associated with lower income, less education, more residential instability, and more instability in adult occupants in the home, whereas time spent in center-based day care was associated with lower exposure.

CONCLUSIONS

Young children from low-income, nonurban communities appear to bear a higher burden of secondhand smoke exposure than previous studies have reported. Results contribute to understanding populations at greater risk, as well as specific, potentially malleable, environmental factors that may be examined as direct contributors to exposure.

IMPLICATIONS

Results suggest that infants from low-income, nonurban families have higher risk for environmental smoke exposure than data from nationally representative samples. Predictors of exposure offer insights into specific factors that may be targeted for risk reduction efforts, specifically conditions of children's physical space. In addition to considering the increases in risk when an adult smoker lives in a child's home, families should also attend to the possible risk embedded within the home itself, such as residual smoke from previous occupants. For high-risk children, day care appears to mitigate the magnitude of exposure by providing extended time in a smoke-free environment.

Secondhand Smoke Exposure in Primary School Children: A Survey in Dhaka, Bangladesh

Introduction

We report on second-hand smoke (SHS) exposure based on saliva cotinine levels among children in Bangladesh—a country with laws against smoking in public places.

Methods

A survey of primary school children from two areas of the Dhaka district was conducted in 2015. Participants completed a questionnaire and provided saliva samples for cotinine measurement to assess SHS exposure with a cut-off range of ≥0.1ng/mL.

Results

Four hundred and eighty-one children studying in year-5 were recruited from 12 primary schools. Of these, 479 saliva samples were found sufficient for cotinine testing, of which 95% (453/479) were positive for recent SHS exposure. Geometric mean cotinine was 0.36 (95% CI = 0.32 to 0.40); 43% (208/479) of children lived with at least one smoker in the household. Only 21% (100/479) reported complete smoking restrictions for residents and visitors; 87% (419/479) also reported being recently exposed to SHS in public spaces. Living with a smoker and number of tobacco selling shops in the neighborhood had positive associations with recent SHS exposure.

Conclusions

Despite having a ban on smoking in public places, recent SHS exposure among children in Bangladesh remains very high. There is an urgent need to reduce exposure to SHS in Bangladeshi children.

Implications

Children bear the biggest burden of disease due to SHS exposure than any other age group. However, children living in many high-income countries have had a sharp decline in their exposure to SHS in recent years. What remains unknown is if children living in low-income countries are still exposed to SHS. Our study suggests that despite having a ban on smoking in public places, most primary school children in Dhaka, Bangladesh are still likely to be exposed to SHS.

JUUL electronic cigarettes: Nicotine exposure and the user experience

BACKGROUND

As of March 2019, JUUL electronic cigarettes are the most popular e-cigarette on the U.S. market, but little is known of nicotine exposure and dependence on JUUL and user experience.

METHODS

JUUL users participated in a community-based study involving questionnaires, saliva collection and a qualitative interview.

RESULTS

Fifteen participants were enrolled (80% male, 53% White) and had an average age of 29.8 (standard deviation = 10) years. Daily exposure to nicotine assessed via salivary cotinine was similar to those reported for other e-cigarette and tobacco cigarette users in general. The majority reported low to moderate nicotine dependence. Qualitative interview themes included: the importance of social networks in adoption and use of the product; device features such as small size and vapor cloud reinforced product use; the product provided satisfaction compared to a tobacco cigarette; and a perceived sense of addiction to the product.

CONCLUSIONS

JUUL e-cigarettes expose users to levels of nicotine similar to other e-cigarettes but may be more satisfying due to unique device features. JUUL may be quite acceptable to tobacco cigarette smokers who are seeking to quit. However, it holds addictive potential and can reinforce long-term nicotine use.

Saliva DNA Methylation Detects Nascent Smoking in Adolescents

Objectives: Early identification of smoking, essential for the successful implementation of interventions, arrests the escalation of smoking and smoking-associated risk behaviors in adolescents. However, because nascent smoking is typically episodic and infrequent, enzyme-linked immunoassay reagent-based approaches that detect cotinine, a key nicotine metabolite, are not effective in identifying adolescents in the earliest stages of smoking. Epigenetic methods may offer an alternative approach for detecting early-stage smokers. In prior work, we and others have shown that the methylation status of cg05575921 of whole-blood DNA accurately predicts smoking status in regularly smoking adults and is sensitive to nascent smoking. Yet, the blood draws necessary to obtain DNA for this method may be poorly accepted by adolescents. Saliva could be an alternative source of DNA. However, the ability of saliva DNA methylation status to predict smoking status among adolescents is unknown. Methods: To explore the possibility of using salivary DNA for screening purposes, we examined the DNA methylation status at cg05575921 in saliva DNA samples from 162 high school aged subjects for whom we also had paired serum cotinine values. Results: Overall, the reliability of self-report of nicotine/tobacco use in these adolescents was poor with 67% of all subjects whose serum levels of cotinine was ≥2 ng/mL (n = 75) denying any use of nicotine-containing products in the past 6 months. However, the correspondence of the two biological measures of smoking was high, with serum cotinine positivity being strongly correlated with cg05575921 methylation (p < 0.0001). Receiver operating characteristic (ROC) analyses showed that cg05575921 methylation status could be used to classify those with positive serum cotinine values (≥2 ng/mL) from those denying smoking and have undetectable levels of cotinine. Conclusions: We conclude that saliva DNA methylation assessments hold promise as a means of detecting nascent smoking.

Misclassification of smoking habits: An updated review of the literature

BACKGROUND

Misclassification of smoking habits leads to underestimation of true relationships between diseases and active smoking, and overestimation of true relationships with passive smoking. Information on misclassification rates can be obtained from studies using cotinine as a marker.

AIM

To estimate overall misclassification rates based on a review and meta-analysis of the available evidence, and to investigate how misclassification rates depend on other factors.

METHODS

We searched for studies using cotinine as a marker which involved at least 200 participants and which provided information on high cotinine levels in self-reported non-, never, or ex-smokers or on low levels in self-reported smokers. We estimated overall misclassification rates weighted on sample size and investigated heterogeneity by various study characteristics. Misclassification rates were calculated for two cotinine cut points to distinguish smokers and non-smokers, the higher cut point intended to distinguish regular smoking.

RESULTS

After avoiding double counting, 226 reports provided 294 results from 205 studies. A total of 115 results were from North America, 128 from Europe, 25 from Asia and 26 from other countries. A study on 6.2 million life insurance applicants was considered separately. Based on the lower cut point, true current smokers represented 4.96% (95% CI 4.32-5.60%) of reported non-smokers, 3.00% (2.45-3.54%) of reported never smokers, and 10.92% (9.23-12.61%) of reported ex-smokers. As percentages of true current smokers, non-, never and ex-smokers formed, respectively, 14.50% (12.36-16.65%), 5.70% (3.20-8.20%), and 8.93% (6.57-11.29%). Reported current smokers represented 3.65% (2.84-4.45%) of true non-smokers. There was considerable heterogeneity between misclassification rates. Rates of claiming never smoking were very high in Asian women smokers, the individual studies reporting rates of 12.5%, 22.4%, 33.3%, 54.2% and 66.3%. False claims of quitting were relatively high in pregnant women, in diseased individuals who may recently have been advised to quit, and in studies considering cigarette smoking rather than any smoking. False claims of smoking were higher in younger populations. Misclassification rates were higher in more recently published studies. There was no clear evidence that rates varied by the body fluid used for the cotinine analysis, the assay method used, or whether the respondent was aware their statements would be validated by cotinine - though here many studies did not provide relevant information. There was only limited evidence that rates were lower in studies classified as being of good quality, based on the extent to which other sources of nicotine were accounted for.

CONCLUSION

It is important for epidemiologists to consider the possibility of bias due to misclassification of smoking habits, especially in circumstances where rates are likely to be high. The evidence of higher rates in more recent studies suggests that the extent of misclassification bias in studies relating passive smoking to smoking-related disease may have been underestimated.

Efficacy of Mobile Phone-Delivered Smoking Cessation Interventions for Socioeconomically Disadvantaged Individuals: A Randomized Clinical Trial

IMPORTANCE

Limited evidence supports mobile phone-delivered cessation interventions for socioeconomically disadvantaged individuals.

OBJECTIVE

To assess the efficacy of mobile phone-delivered cessation interventions targeted to smokers at neighborhood sites serving racial/ethnic minority and socioeconomically disadvantaged individuals.

DESIGN, SETTING, AND PARTICIPANTS

This group-randomized clinical trial with neighborhood site serving as the sampling unit compared smoking cessation interventions that included (1) nicotine replacement therapy (NRT), (2) NRT plus text messaging, and (3) NRT plus text messaging plus proactive counseling via mobile phone. Recruitment took place at churches, public housing complexes, and community centers located throughout the Houston, Texas, area. A total of 624 current cigarette smokers 18 years or older were enrolled at neighborhood sites from August 13, 2011, through December 12, 2014. Final follow-up was completed on June 12, 2015, and data were analyzed from August 17, 2017, through May 10, 2018, based on intention to treat.

INTERVENTIONS

Nicotine replacement therapy consisted of transdermal nicotine patches; NRT plus text messages, transdermal nicotine patches and individually tailored mobile phone text messages; and NRT plus text plus call, transdermal patches, individually tailored mobile phone text messages, and proactive counseling via mobile phone.

MAIN OUTCOMES AND MEASURES

The primary outcome was smoking abstinence at 6 months, defined as (1) biochemically verified smoking abstinence (calculated among a subgroup of 377 participants) as determined by saliva cotinine level; and (2) self-reported 30-day abstinence (calculated among all 624 participants).

RESULTS

The study sample included 624 current cigarette smokers (50.6% female; mean [SD] age, 45.8 [12.8] years). Among the 377 participants eligible for biochemical verification, 127 self-reported 30-day abstinence and were asked to provide saliva samples. Of these, 98 samples were returned (participants who did not return samples were coded as smoking). Biochemically verified abstinence rates were 12.0% for NRT, 12.0% for NRT plus text, and 25.5% for NRT plus text plus call. Participants in the NRT plus text plus call group were 2.11 (95% CI, 1.00-4.48) times more likely to be biochemically verified as abstinent compared with the NRT group. No differences in biochemically verified abstinence between the NRT plus text group and the NRT group were observed. Similar associations were observed with the self-report cessation outcomes.

CONCLUSIONS AND RELEVANCE

Findings indicate that assignment to an intervention consisting of text messaging alone may not increase cessation rates for socioeconomically disadvantaged smokers. However, text messaging plus proactive counseling may be an efficacious option.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00948129.

Quitline treatment dose predicts cessation outcomes among safety net patients linked with treatment via Ask-Advise-Connect

The efficacy of tobacco treatment delivered by state quitlines in diverse populations is well-supported, yet little is known about associations between treatment dose and cessation outcomes following the implementation of Ask-Advise-Connect (AAC), an electronic health record-based systematic referral process that generates a high volume of proactive calls from the state quitline to smokers. The current study is a secondary analysis of a 34-month implementation trial evaluating ACC in 13 safety-net clinics in Houston, TX. Treatment was delivered by a quitline and comprised up to five proactive, telephone-delivered multi-component cognitive-behavioral treatment sessions. Associations between treatment dose and abstinence were examined. Abstinence was assessed by phone six months after treatment enrollment, and biochemically confirmed via mailed saliva cotinine. Among smokers who enrolled in treatment and agreed to follow-up (n = 3704), 29.2% completed no treatment sessions, 35.5% completed one session, 16.4% completed two sessions, and 19.0% completed ≥three sessions. Those who completed one (vs. no) sessions were no more likely to report abstinence (OR: 0.98). Those who completed two (vs. no) sessions were nearly twice as likely to report abstinence (OR: 1.83). Those who completed ≥three (vs. no) sessions were nearly four times as likely to report abstinence (OR: 3.70). Biochemically-confirmed cessation outcomes were similar. Most smokers received minimal or no treatment, and treatment dose had a large impact on abstinence. Results highlight the importance of improving engagement in evidence-based treatment protocols following enrollment. Given that motivation to quit fluctuates, systematically offering enrollment to all smokers at all visits is important.

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The majority of smokers received minimal or no evidence-based tobacco treatment.

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Smokers who completed 0 or 1 treatment sessions were unlikely to achieve abstinence.

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Completion of 2 calls doubled the likelihood of abstinence at 6 months.

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Completion of ≥3 calls was associated with a near quadrupling of abstinence rates.

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Improving engagement in evidence-based treatment protocols is a research priority.

Estimation of compliance with exclusive smoking of very low nicotine content cigarettes using plasma cotinine

Regulations requiring a reduction of the nicotine content in cigarettes to minimally addictive levels could significantly reduce the public health impact of cigarette smoking. Clinical trials evaluating this strategy are ongoing and methods have been developed to use nicotine biomarkers to estimate compliance with use of very low nicotine content cigarettes (VLNCs). To date, these methods have not considered the potential contribution of nicotine absorption from environmental tobacco smoke (ETS) among research participants. This study used data from 100 randomly selected study completers in ongoing clinical trials of VLNCs (50 randomized to Usual Nicotine Content Cigarettes (UNCs) and 50 to VLNCs) to assess the use of plasma cotinine to estimate compliance. Plasma cotinine and smoking behavior were recorded at baseline after 2 weeks smoking UNC cigarettes, and then after 18 weeks of either continuing smoking UNCs or reducing the nicotine content such that the last 6 weeks comprised smoking VLNCs. Plasma cotinine remained stable (267 ng/ml) in the UNC group but reduced to 93 ng/ml in the VLNC group (p < 0.01). Compliance with smoking VLNCs was first estimated by comparing the cotinine per cigarette on VLNCs with UNCs after allowing for potential compensatory smoking. We found that 29 (58%) of the VLNC group were compliant. Adjusting for potential ETS exposure estimated 32 (64%) to be compliant. This latter group (n = 32) had a mean plasma cotinine on VLNCs of 7 ng/ml (range = 3-16.4 ng/ml). Adjusting for potential ETS exposure may improve identification of participants who plausibly complied with exclusive VLNC use.

Early childhood exposure to secondhand smoke and behavioural problems in preschoolers

Evidence on behavioural abnormalities in children exposed to secondhand smoke is limited. This study examined the relation between infant/ toddler cotinine concentration, a biomarker of secondhand smoke exposure, and behavioural problems in preschoolers who were unexposed to maternal smoking during gestation. A prospective cohort of 301 non-smoking mothers with their young children aged ≤18 months visiting postnatal primary care clinics in Hong Kong was enrolled in 2012 and followed by telephone survey 3 years afterwards. Saliva was collected at baseline for cotinine assay. Child behavioural health at 3-year follow-up was assessed by the parent-reported Strengths and Difficulties Questionnaire (SDQ). We conducted multivariable linear regressions to compute regression coefficients (b) of SDQ scores in relation to salivary cotinine level. Mean ± SD age of children at follow-up was 3.7 ± 0.5 years and 50.8% were boys. After adjusting for age, sex, birthweight, household income, housing type, maternal education and depressive symptoms, greater cotinine concentrations during early childhood were associated with greater conduct problems (b = 0.90, 95% CI 0.03-1.76) and hyperactivity/ inattention (b = 1.12, 95% CI 0.07-2.17) at preschool age. This study corroborates previous findings on the potential role of secondhand smoke in development of child behavioural problems.

Intergenerational transmission of nicotine within families: Have e-cigarettes influenced passive smoking?

Using an objective biomarker of active and passive smoking, we estimate Galtonian regressions of nicotine transmission and test whether the use of new nicotine delivery products (NDP) by parents had an influence on the transmission to children through passive smoking. We find evidence of a strong intergenerational transmission through passive smoking and that this is around four times larger for mothers compared to fathers. Moreover, we estimate an intention to treat difference-in-differences (DiD) model using parental cotinine as a continuous measure of exposure to the treatment and we find that the level of transmission of cotinine from parents was reduced to 51 per cent of the previous level just after the spread in the use of e-cigarettes in England and to 77 per cent when considering transmission from mothers. This is confirmed also by a DiD model which considers interaction between cotinine levels and self-reported use of NDP by parents and suggests that lower taxation of these devices may be justified on externality grounds.

Characterising the Exposure of Prison Staff to Second-Hand Tobacco Smoke

Second-hand tobacco smoke (SHS) is an avoidable and harmful exposure in the workplace but >25000 prison staff continue to be exposed on a daily basis in the UK and many more worldwide. SHS exposures in prisons are incompletely understood but may be considerable given the large proportion of smoking prisoners and limited ventilation. This study characterized the exposure of prison staff to SHS in all 15 prisons in Scotland using multiple methods. Exposure assessment strategies included 6-day area measurement of fine Particulate Matter (PM_2.5) and airborne nicotine in each prison together with short (30-minute) measurements of PM_2.5 covering a range of locations/activities. Pre- and post-shift saliva samples were also gathered from non-smoking staff and analysed for cotinine to estimate exposure. There was evidence of exposure to SHS in all prisons from the results of PM_2.5 and nicotine measurements. The salivary cotinine results from a sub-sample of non-smoking workers indicated SHS exposures of similar magnitude to those provided by the 6-day area measurements of PM_2.5. There was a high degree of exposure variability with some locations/activities involving exposure to SHS concentrations that were comparable to those measured in bars in Scotland prior to smoke-free legislation in 2006. The median shift exposure to SHS-PM_2.5 was ~20 to 30 µg m⁻³ and is broadly similar to that experienced by someone living in a typical smoking home in Scotland. This is the most comprehensive assessment of prison workers’ exposure to SHS in the world. The results are highly relevant to the development of smoke-free policies in prisons and should be considered when deciding on the best approach to provide prison staff with a safe and healthy working environment.

Unique Lipid Signatures of Extracellular Vesicles from the Airways of Asthmatics

Asthma is a chronic inflammatory disease process involving the conductive airways of the human lung. The dysregulated inflammatory response in this disease process may involve multiple cell-cell interactions mediated by signaling molecules, including lipid mediators. Extracellular vesicles (EVs) are lipid membrane particles that are now recognized as critical mediators of cell-cell communication. Here, we compared the lipid composition and presence of specific lipid mediators in airway EVs purified from the bronchoalveolar lavage (BAL) fluid of healthy controls and asthmatic subjects with and without second-hand smoke (SHS) exposure. Airway exosome concentrations were increased in asthmatics, and correlated with blood eosinophilia and serum IgE levels. Frequencies of HLA-DR⁺ and CD54⁺ exosomes were also significantly higher in asthmatics. Lipidomics analysis revealed that phosphatidylglycerol, ceramide-phosphates, and ceramides were significantly reduced in exosomes from asthmatics compared to the non-exposed control groups. Sphingomyelin 34:1 was more abundant in exosomes of SHS-exposed asthmatics compared to healthy controls. Our results suggest that chronic airway inflammation may be driven by alterations in the composition of lipid mediators within airway EVs of human subjects with asthma.

[Biomarkers of Smoking - Which Cut-Off Values Should be Used?]

Biomarkers of Smoking - Which Cut-Off Values Should be Used? Abstract. Verification of smoking status by means of biomarkers is important for treatment decisions of patients with smoking-related diseases. Cotinine is currently the best biomarker to document nicotine consumption. A low cost alternative method to determine smoking status is by measurement of carboxyhemoglobin (CO-Hb) in the exhaled breath. The main disadvantage of CO-Hb is the short half-life. The appropriate cut-off value for active nicotine consumption in Switzerland is 50 ng/ml or higher cotinine in the urine or 10 ng/ml and 12 ng/ml in serum and saliva, respectively. CO-Hb levels greater than 2 % indicate smoking with high probability, levels above 3 % with very high probability.

Tobacco smoke exposure in early life and adolescence in relation to lung function

Maternal smoking during pregnancy is associated with impaired lung function among young children, but less is known about long-term effects and the impact of adolescents' own smoking. We investigated the influence of maternal smoking during pregnancy, secondhand smoke exposure and adolescent smoking on lung function at age 16 years.

The BAMSE (Barn/Child, Allergy, Milieu, Stockholm, Epidemiology) birth cohort collected information on participants' tobacco smoke exposure through repeated questionnaires, and measured saliva cotinine concentrations at age 16 years. Participants performed spirometry and impulse oscillometry (IOS) at age 16 years (n=2295).

Exposure to maternal smoking during pregnancy was associated with reduced forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ratio of −1.1% (95% CI −2.0 to −0.2%). IOS demonstrated greater resistance at 5–20 Hz (R_5–20) in participants exposed to maternal smoking during pregnancy. Adolescents who smoked had reduced FEV₁/FVC ratios of −0.9% (95% CI −1.8 to −0.1%) and increased resistance of 6.5 Pa·L^–1·s (95% CI 0.7 to 12.2 Pa·L^–1·s) in R_5–20. Comparable associations for FEV₁/FVC ratio were observed for cotinine concentrations, using ≥12 ng·mL⁻¹ as a cut-off for adolescent smoking.

Maternal smoking during pregnancy was associated with lower FEV₁/FVC ratios and increased airway resistance. In addition, adolescent smoking appears to be associated with reduced FEV₁/FVC ratios and increased peripheral airway resistance.

Maternal smoking in utero and teenage smoking are associated with indices of airway obstruction at age 16 yearshttp://ow.ly/NwF030jFS2W

Paternal smoking and maternal protective behaviors at home on infant's saliva cotinine levels

BackgroundWe investigated the association between paternal smoking, avoidance behaviors and maternal protective actions and smoke-free home rules with infant's saliva cotinine in Hong Kong.MethodsSix hundred and seventy-five non-smoking mothers (mean age 32.6 years) who attended the maternal-child health clinics with their newborns aged ≤18 months completed a questionnaire about paternal smoking and avoidance behaviors, maternal protective actions, smoke-free rules at home, and infant's second-hand smoke (SHS) exposure. Three hundred and eighty-nine infants provided saliva sample and its cotinine was tested.ResultsThe geometric mean of infant's saliva cotinine was 1.07 ng/ml (95% confidence interval (CI): 0.98, 1.16). Infants living in smoking families with SHS exposure had significantly higher cotinine level than in non-smoking families (adjusted β=0.25, 95% CI: 0.16, 0.33). Paternal smoking near infants (within 1.5 m) was associated with higher cotinine level (adjusted β=0.60, 95% CI: 0.22, 0.98), which was not reduced by avoidance behaviors (e.g., smoking in kitchen or balcony). Even fathers smoking ≥3 m away from infants was associated with higher cotinine level than non-smoking families (adjusted β=0. 09, 95% CI: 0.01, 0.16). Maternal protective actions and smoke-free home rules were not significantly associated with reduced cotinine level.ConclusionPaternal smoking avoidance, maternal protective actions, and smoke-free policy at home did not reduce infant's saliva cotinine.

Examining the Validity of Self-reported Primary and Secondary Exposure to Cigarette Smoke in Adolescent Girls: The Utility of Salivary Cotinine as a Biomarker

BACKGROUND

Studies of cigarette use and exposure often rely on either self-report or cotinine assay. In adolescence it is not clear how well assays and self-report correspond, or what effect estrogen exposure has on cotinine.

OBJECTIVES

This study sought to identify optimal cut-points for salivary cotinine thresholds for girls with primary, secondary, and no smoke exposure, and whether menarche and hormone contraceptive use are important for interpreting salivary cotinine.

METHODS

This longitudinal prospective study recruited 262 healthy adolescent girls who participated in three annual interviews across 24 months. Salivary cotinine assays and self-report of primary and secondary smoke exposure, menarcheal status, and hormone contraceptive use were collected.

RESULTS

No adolescents reported primary smoke exposure without secondary exposure. Optimal cut-points for distinguishing primary smoke exposure from secondary-only and no smoke exposure were 1.05 and 3.01 ng/ml, respectively based on receiver operator curves (ROC); no reliable cut-point for secondary-only versus no smoke exposure was identified. The ideal salivary cotinine cut-point to distinguish primary smoke exposure varied by hormone contraceptive use and was 2.14 ng/ml for those using progesterone contraceptives, higher than that of girls using estrogen contraceptives and those not using hormone contraceptives.

CONCLUSIONS

This study is the first to examine variance in salivary cotinine cut-points based on hormone exposure for adolescent girls, with findings indicating that hormone contraceptive use in particular may be a key consideration when identifying adolescent smoking. The use of previously recommended salivary cotinine cut-points of 3.85 ng/ml or higher may overestimate nonsmokers.

Accuracy of self-reported smoking abstinence in clinical trials of hospital-initiated smoking interventions

AIMS

To estimate the prevalence and predictors of failed biochemical verification of self-reported abstinence among participants enrolled in trials of hospital-initiated smoking cessation interventions.

DESIGN

Comparison of characteristics between participants who verified and those who failed to verify self-reported abstinence.

SETTINGS

Multi-site randomized clinical trials conducted between 2010 and 2014 in hospitals throughout the United States.

PARTICIPANTS

Recently hospitalized smokers who reported tobacco abstinence 6 months post-randomization and provided a saliva sample for verification purposes (n = 822).

MEASUREMENTS

Outcomes were salivary cotinine-verified smoking abstinence at 10 and 15 ng/ml cut-points. Predictors and correlates included participant demographics and tobacco use; hospital diagnoses and treatment; and study characteristics collected via surveys and electronic medical records.

FINDINGS

Usable samples were returned by 69.8% of the 1178 eligible trial participants who reported 7-day point prevalence abstinence. The proportion of participants verified as quit was 57.8% [95% confidence interval (CI) = 54.4, 61.2; 10 ng/ml cut-off] or 60.6% (95% CI = 57.2, 63.9; 15 ng/ml). Factors associated independently with verification at 10 ng/ml were education beyond high school education [odds ratio (OR) = 1.51; 95% CI = 1.07, 2.11], continuous abstinence since hospitalization (OR = 2.82; 95% CI = 2.02, 3.94), mailed versus in-person sample (OR = 3.20; 95% CI = 1.96, 5.21) and race. African American participants were less likely to verify abstinence than white participants (OR = 0.64; 95% CI = 0.44, 0.93). Findings were similar for verification at 15 ng/ml. Verification rates did not differ by treatment group.

CONCLUSIONS

In the United States, high rates (40%) of recently hospitalized smokers enrolled in smoking cessation trials fail biochemical verification of their self-reported abstinence.

Tobacco cessation interventions for young people

BACKGROUND

Most tobacco control programmes for adolescents are based around prevention of uptake, but teenage smoking is still common. It is unclear if interventions that are effective for adults can also help adolescents to quit. This is the update of a Cochrane Review first published in 2006.

OBJECTIVES

To evaluate the effectiveness of strategies that help young people to stop smoking tobacco.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group's Specialized Register in June 2017. This includes reports for trials identified in CENTRAL, MEDLINE, Embase and PsyclNFO.

SELECTION CRITERIA

We included individually and cluster-randomized controlled trials recruiting young people, aged under 20 years, who were regular tobacco smokers. We included any interventions for smoking cessation; these could include pharmacotherapy, psycho-social interventions and complex programmes targeting families, schools or communities. We excluded programmes primarily aimed at prevention of uptake. The primary outcome was smoking status after at least six months' follow-up among those who smoked at baseline.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility of candidate trials and extracted data. We evaluated included studies for risk of bias using standard Cochrane methodology and grouped them by intervention type and by the theoretical basis of the intervention. Where meta-analysis was appropriate, we estimated pooled risk ratios using a Mantel-Haenszel fixed-effect method, based on the quit rates at six months' follow-up.

MAIN RESULTS

Forty-one trials involving more than 13,000 young people met our inclusion criteria (26 individually randomized controlled trials and 15 cluster-randomized trials). We judged the majority of studies to be at high or unclear risk of bias in at least one domain. Interventions were varied, with the majority adopting forms of individual or group counselling, with or without additional self-help materials to form complex interventions. Eight studies used primarily computer or messaging interventions, and four small studies used pharmacological interventions (nicotine patch or gum, or bupropion). There was evidence of an intervention effect for group counselling (9 studies, risk ratio (RR) 1.35, 95% confidence interval (CI) 1.03 to 1.77), but not for individual counselling (7 studies, RR 1.07, 95% CI 0.83 to 1.39), mixed delivery methods (8 studies, RR 1.26, 95% CI 0.95 to 1.66) or the computer or messaging interventions (pooled RRs between 0.79 and 1.18, 9 studies in total). There was no clear evidence for the effectiveness of pharmacological interventions, although confidence intervals were wide (nicotine replacement therapy 3 studies, RR 1.11, 95% CI 0.48 to 2.58; bupropion 1 study RR 1.49, 95% CI 0.55 to 4.02). No subgroup precluded the possibility of a clinically important effect. Studies of pharmacotherapies reported some adverse events considered related to study treatment, though most were mild, whereas no adverse events were reported in studies of behavioural interventions. Our certainty in the findings for all comparisons is low or very low, mainly because of the clinical heterogeneity of the interventions, imprecision in the effect size estimates, and issues with risk of bias.

AUTHORS' CONCLUSIONS

There is limited evidence that either behavioural support or smoking cessation medication increases the proportion of young people that stop smoking in the long-term. Findings are most promising for group-based behavioural interventions, but evidence remains limited for all intervention types. There continues to be a need for well-designed, adequately powered, randomized controlled trials of interventions for this population of smokers.

Biomarkers of exposure to new and emerging tobacco delivery products

Accurate and reliable measurements of exposure to tobacco products are essential for identifying and confirming patterns of tobacco product use and for assessing their potential biological effects in both human populations and experimental systems. Due to the introduction of new tobacco-derived products and the development of novel ways to modify and use conventional tobacco products, precise and specific assessments of exposure to tobacco are now more important than ever. Biomarkers that were developed and validated to measure exposure to cigarettes are being evaluated to assess their use for measuring exposure to these new products. Here, we review current methods for measuring exposure to new and emerging tobacco products, such as electronic cigarettes, little cigars, water pipes, and cigarillos. Rigorously validated biomarkers specific to these new products have not yet been identified. Here, we discuss the strengths and limitations of current approaches, including whether they provide reliable exposure estimates for new and emerging products. We provide specific guidance for choosing practical and economical biomarkers for different study designs and experimental conditions. Our goal is to help both new and experienced investigators measure exposure to tobacco products accurately and avoid common experimental errors. With the identification of the capacity gaps in biomarker research on new and emerging tobacco products, we hope to provide researchers, policymakers, and funding agencies with a clear action plan for conducting and promoting research on the patterns of use and health effects of these products.

Tobacco Exposure and Conditional Weight-for-Length Gain by 2 Years of Age

Objective

To prospectively examine dose-response and timing effects of prenatal (PTE) and postnatal tobacco exposure on obesity risk assessed by conditional weight-for-length gain (CWFLG), by 2 years of age. CWFLG over the first 2 years of life was examined for 117 PTE and 57 nonexposed children. Repeated assessments of PTE were conducted beginning in the first trimester of pregnancy, using multiple methods. PTE or postnatal exposure status was not predictive of CWFLG. However, there was a dose-response association and an association with fetal exposure ascertained by infant meconium positive for nicotine and metabolites. PTE is related to restricted growth at birth, yet associated with accelerated CWFLG by 2 years of age, a measure that controls for birthweight differences. Results highlight the importance of examining dose-response and timing of exposure associations, along with the importance of obesity risk-reduction interventions within the first 2 years of life among PTE children.

In-utero exposure to nicotine alters the development of the rabbit cardiac conduction system and provides a potential mechanism for sudden infant death syndrome

In-utero exposure to tobacco smoke remains the highest risk factor for sudden infant death syndrome (SIDS). To alleviate the risks, nicotine replacement therapies are often prescribed to women who wish to quit smoking during their pregnancy. Cardiac arrhythmias is considered the final outcome leading to sudden death. Our goal in this study was to determine if exposing rabbit fetus to nicotine altered the cardiac conduction system of newborn kittens in a manner susceptible to cause SIDS. Using neuronal markers and a series of immunohistological and electrophysiological techniques we found that nicotine delayed the development of the cardiac pacemaker center (sinoatrial node) and decreased its innervation. At the molecular level, nicotine favored the expression of cardiac sodium channels with biophysical properties that will tend to slow heart rate and diminish electrical conduction. Our results show that alterations of the cardiac sodium current may contribute to the bradycardia, conduction disturbances and other cardiac arrhythmias often associated to SIDS and raise awareness on the use of replacement therapy during pregnancy.

Healthy families: study protocol for a randomized controlled trial of a screening, brief intervention, and referral to treatment intervention for caregivers to reduce secondhand smoke exposure among pediatric emergency patients

Background

Involuntary exposure to secondhand smoke (SHSe) is an important cause of morbidity in children who present to the pediatric emergency department (PED) and urgent care (UC). SHSe interventions delivered in the PED and UC would benefit both the smoker and child, but there have been no large trials testing the efficacy of such interventions. The Healthy Families program is the first randomized controlled trial to test whether a screening, brief intervention, and referral to treatment (SBIRT) intervention delivered in the PED and UC will be effective in decreasing SHSe in children and increasing cessation in smokers.

Methods/design

This trial uses a randomized, two-group design in which caregiver-smokers of children 0–17 years old are recruited from the PED and UC. Eligible caregiver-smokers are randomized to either the: 1) SBIRT Condition with face-to-face, tailored counseling that focuses on the child’s illness, the importance of reducing child SHSe, caregiver smoking cessation, and the option to receive nicotine replacement therapy; or 2) Healthy Habits Control Condition which includes face-to-face, tailored attention control “5–2–1-0” counseling that focuses on improving the child’s health. Dyadic assessments are conducted in-person at baseline, and via email, phone, or in-person at 6-weeks and 6-months. The primary outcomes are biochemically-verified, 7-day point prevalence and prolonged smoking abstinence. Secondary outcomes are cigarettes smoked per week, 24 h quit attempts, and biochemically validated child SHSe at each time point. The costs of this intervention will also be analyzed.

Discussion

This study will test an innovative, multilevel intervention designed to reduce child SHSe and increase smoking cessation in caregivers. If effective and routinely used, this SBIRT model could reach at least one million smokers a year in the U.S., resulting in significant reductions in caregivers’ tobacco use, SHSe-related pediatric illness, and healthcare costs in this population of children.

Trial registration

ClinicalTrials.gov Identifier: NCT02531594. Date of registration: August 4, 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4278-8) contains supplementary material, which is available to authorized users.

Implications of Misclassification Errors in Empirical Studies of Adolescent Smoking Behaviours

Misclassification errors in a dependent variable can introduce attenuation bias to covariate effects in a binary choice model. Misreporting of smoking behaviours by adolescents has been widely documented. However, the consequence in empirical studies of adolescent smoking participation has received little attention. This study uses the Health Survey for England (HSE) to investigate the extent and implication of misclassification errors in self-reported smoking among adolescents aged 11-15 years. The HSE contains both a self-reported smoking component and an objective measure of smoking obtained from saliva cotinine assays. Saliva cotinine concentration ≥12 ng/ml is considered the 'true' indicator of adolescent smoking participation against which self-reported smoking is compared. The findings show that smoking is misreported in this age group, resulting in a downwards bias of marginal effect estimates. Given the widespread use of self-reported smoking data, this study explores the performance of the Hausman, Abrevaya and Scott-Morton-modified maximum likelihood estimation (HAS approach) in recovering true estimates of covariate effects. In this context, the HAS approach performs better when the misclassification probabilities are treated as constants compared with when they are treated as conditionally dependent parameters. Copyright © 2016 John Wiley & Sons, Ltd.

Effectiveness of personalised risk information and taster sessions to increase the uptake of smoking cessation services (Start2quit): a randomised controlled trial

BACKGROUND

National Health Service Stop Smoking Services (SSSs) offer help to smokers motivated to quit; however, attendance rates are low and recent figures show a downward trend. We aimed to assess the effectiveness of a two-component personalised intervention on attendance at SSSs.

METHODS

We did this randomised controlled trial in 18 SSSs in England. Current smokers (aged ≥16 years) were identified from medical records in 99 general practices and invited to participate by their general practitioner. Individuals who gave consent, were motivated to quit, and had not attended the SSS within the past 12 months, were randomly assigned (3:2), via computer-generated randomisation with permuted blocks (block size of five), to receive either an individually tailored risk letter and invitation to attend a no-commitment introductory session run by the local SSS (intervention group) or a standard generic letter advertising the local SSS (control group). Randomisation was stratified by sex. Masking of participants to receipt of a personal letter and invitation to a taster session was not possible. The personal letter was generated by a research assistant, but the remainder of the research team were masked to group allocation. General practitioners, practice staff, and SSS advisers were unaware of their patients' allocation. The primary outcome was attendance at the first session of an SSS course within 6 months from randomisation. We did analysis by intention to treat. This trial is registered with Current Controlled Trials, number ISRCTN 76561916.

FINDINGS

Recruitment, collection of baseline data, delivery of the intervention, and follow up of participants took place between Jan 31, 2011, and July 12, 2014. We randomly assigned 4384 smokers to the intervention group (n=2636) or the control group (n=1748); 4383 participants comprised the intention-to-treat population. Attendance at the first session of an SSS course was significantly higher in the intervention group than in the control group (458 [17·4%] vs 158 [9·0%] participants; unadjusted odds ratio 2·12 [95% CI 1·75-2·57]; p<0·0001).

INTERPRETATION

Delivery of personalised risk information alongside an invitation to an introductory session more than doubled the odds of attending the SSS compared with a standard generic invitation to contact the service. This result suggests that a more proactive approach, combined with an opportunity to experience local services, can reduce patient barriers to receiving treatment and has high potential to increase uptake.

FUNDING

National Institutes of Health Research Health Technology Assessment.

Overview of Cotinine Cutoff Values for Smoking Status Classification

While cotinine is commonly used as a biomarker to validate self-reported smoking status, the selection of an optimal cotinine cutoff value for distinguishing true smokers from true nonsmokers shows a lack of standardization among studies. This review describes how the cutoff values have been derived, and explains the issues involved in the generalization of a cutoff value. In this study, we conducted an English-language literature search in PubMed using the keywords “cotinine” and “cutoff” or “self-reported” and “smoking status” and “validation” for the years 1985–2014. We obtained 104 articles, 32 of which provided (1) sensitivity and specificity of a cutoff value and (2) determination methods for the given cutoff value. We found that the saliva cotinine cutoff value range of 10–25 ng/mL, serum and urine cotinine cutoff of 10–20 ng/mL and 50–200 ng/mL, respectively, have been commonly used to validate self-reported smoking status using a 2 × 2 table or a receiver operating characteristics (ROC) curve. We also found that recent large population-based studies in the U.S. and UK reported lower cutoff values for cotinine in serum (3 ng/mL) and saliva (12 ng/mL), compared to the traditionally accepted ones (15 and 14 ng/mg, respectively).

Study protocol for a non-inferiority trial of a blended smoking cessation treatment versus face-to-face treatment (LiveSmokefree-Study)

BACKGROUND

Smoking cessation can significantly reduce the risk of developing smoking-related diseases. Several face-to-face and web-based treatments have shown to be effective. Blending of web-based and face-to-face treatment is expected to improve smoking cessation treatment. The primary objective of this study is to compare the prolonged abstinence rate of the blended smoking cessation treatment with the face-to-face treatment. Secondary objectives are to assess the benefits of blended treatment in terms of cost effectiveness and patient satisfaction, and to identify mechanisms underlying successful smoking cessation.

METHODS/DESIGN

This study will be a single-center randomized controlled non-inferiority-trial with parallel group design. Patients (n = 344) will be randomly assigned to either the blended or the face-to-face group. Both treatments will consist of ten sessions with equal content held within 6 months. In the blended treatment five out of ten sessions will be delivered online. The treatments will cover the majority of behavior change techniques that are evidence-based within smoking cessation counseling. All face-to-face sessions in both treatments will take place at the outpatient smoking cessation clinic of a hospital. The primary outcome parameter will be biochemically validated prolonged abstinence at 15 months from the start of the smoking cessation treatment.

DISCUSSION

This RCT will be the first study to examine the effectiveness of a blended smoking cessation treatment. It will also be the first study to explore patient satisfaction, adherence, cost-effectiveness, and the clinically relevant influencing factors of a blended smoking cessation treatment. The findings of this RCT are expected to substantially strengthen the base of evidence available to inform the development and delivery of smoking cessation treatment.

TRIAL REGISTRATION

Nederlands Trialregister NTR5113 . Registered 24 March 2015.

Lung cancer in never smokers in the UK Million Women Study

To assess directly the effects of various risk factors on lung cancer incidence among never smokers, large prospective studies are needed. In a cohort of 1.2 million UK women without prior cancer, half (634,039) reported that they had never smoked. Mean age at recruitment was 55 (SD5) years, and during 14 (SD3) years of follow-up, 0.2% (1,469) of these never smokers developed lung cancer. Cox regression was used to estimate relative risks (RRs) of lung cancer for 34 potential risk factors, of which 31 were nonsignificant (p > 0.05). The remaining three risk factors were associated with a significantly increased incidence of lung cancer in never smokers: non-white vs. white ethnicity (RR = 2.34, 95% CI 1.55-3.52, p < 0.001), asthma requiring treatment vs. not (RR = 1.32, 1.10-1.58, p = 0.003) and taller stature (height ≥ 165 cm vs. <160 cm: RR = 1.16, 1.03-1.32, p = 0.02). There was little association with other sociodemographic, anthropometric or hormonal factors, or with dietary intakes of meat, fish, fruit, vegetables and fiber. The findings were not materially affected by restricting the analyses to adenocarcinomas, the most common histological type among never smokers.

Comparative Effectiveness of an Internet-Based Smoking Cessation Intervention Versus Clinic-Based Specialty Care for Veterans

INTRODUCTION

The primary objective of this project was to examine the effectiveness of an Internet-based smoking cessation intervention combined with a tele-health medication clinic for nicotine replacement therapy (NRT) compared to referral to clinic-based smoking cessation care.

METHODS

A total of 413 patients were proactively recruited from the Durham VA Medical Center and followed for 12 months. Patients were randomized to receive either a referral to VA specialty smoking cessation care (control) or to the Internet intervention and tele-health medication clinic. Primary outcomes included (1) intervention reach, (2) self-reported 7-day point prevalence abstinence rates at 3 months and 12 months, and 3) relative cost-effectiveness.

RESULTS

Reach of the Internet intervention and use of smoking cessation aids were significantly greater compared to the control. At 3 months-post randomization, however, there were no significant differences in quit rates: 17% (95% CI: 12%–23%) in the Internet-based intervention compared to 12% (95% CI: 8%–17%) in the control arm. Similarly, there were no differences in quit rates at 12 months (13% vs. 16%). While costs associated with the Internet arm were higher due to increased penetration and intensity of NRT use, there were no statistically significant differences in the relative cost effectiveness (e.g., life years gained, quality adjusted life years) between the two arms.

CONCLUSIONS

Current results suggest that using an electronic medical record to identify smokers and proactively offering smoking cessation services that are consistent with US Public Health Guidelines can significantly reduce smoking in veterans. Novel interventions that increase the reach of intensive treatment are needed to maximize quit rates in this population.