Hans Gilljam

Validity of self reports in a cohort of Swedish adolescent smokers and smokeless tobacco (snus) users

Objective: To validate self reports of cigarette and smokeless tobacco (snus) use in a prospective cohort of adolescents. Design: A cross sectional analysis of a cohort sub-sample. Setting: County of Stockholm, Sweden. Subjects: 520 adolescents in the final grade of junior high school (mean age 15.0 years). Main outcome measure: Concordance between self reported tobacco use and saliva cotinine concentration. Results: Using a cut point of 5 ng/ml saliva cotinine to discriminate active tobacco use, there was a 98% concordance between self reported non-use in the past month and cotinine concentration. The sensitivity of the questionnaire compared to the saliva cotinine test, used as the gold standard, was 90% and the specificity 93%. One hundred and fifteen out of 520 subjects (22%) reported monthly tobacco use. Among these, 67% (46/69) of the exclusive cigarette smokers, 82% (23/28) of exclusive snus users, and 94% (15/16) of mixed users (cigarettes + snus) had cotinine concentrations above 5 ng/ml. Among subjects reporting daily use 96% (64/67) had saliva cotinine concentrations above the cut point. Exclusive current cigarette users were more likely to be classified discordantly by questionnaire and cotinine test compared to snus users (odds ratio 3.2, 95% confidence interval 1.2 to 8.6). Conclusion: This study confirms the reliability of adolescents’ self reported tobacco use. In a context of low exposure to environmental tobacco smoke a cut off for saliva cotinine of 5 ng/ml reliably discriminated tobacco users from non-users. Irregular use of tobacco in this age group probably explains the discrepancy between self reported use and cotinine concentrations.

Increased bronchial chloride concentration in cystic fibrosis

Ten patients with cystic fibrosis (CF) and 10 patients with severe chronic bronchitis were analysed for bronchial electrolyte composition. Samples aspirated from the left main bronchus by a fibre-optic bronchoscope were dissolved in an iso-osmolar solution of N-acetylcysteine, and separated from cells and bacteria by gentle centrifugation. The concentrations of potassium and calcium were measured by flame emission and atomic absorption spectrometry, and found to be similar in both groups of patients. The mean concentration of chloride, measured by coulometric titration, was significantly higher in patients with CF than in patients with chronic bronchitis (170 vs. 85 mmol l-1, p less than 0.01). The findings are consistent with a functional abnormality of the chloride channels of the airway epithelium in patients with CF.

Quitting cigarettes completely or switching to smokeless tobacco: do US data replicate the Swedish results?

Background: Swedish male smokers are more likely than female smokers to switch to smokeless tobacco (snus) and males’ smoking cessation rate is higher than that of females. These results have fuelled international debate over promoting smokeless tobacco for harm reduction. This study examines whether similar results emerge in the United States, one of few other western countries where smokeless tobacco has long been widely available. Methods: US data source: national sample in Tobacco Use Supplement to Current Population Survey, 2002, with 1-year follow-up in 2003. Analyses included adult self-respondents in this longitudinal sample (n = 15 056). Population-weighted rates of quitting smoking and switching to smokeless tobacco were computed for the 1-year period. Results: Among US men, few current smokers switched to smokeless tobacco (0.3% in 12 months). Few former smokers turned to smokeless tobacco (1.7%). Switching between cigarettes and smokeless tobacco, infrequent among current tobacco users (<4%), was more often from smokeless to smoking. Men quit smokeless tobacco at three times the rate of quitting cigarettes (38.8% vs 11.6%, p<0.001). Overall, US men have no advantage over women in quitting smoking (11.7% vs 12.4%, p = 0.65), even though men are far likelier to use smokeless tobacco. Conclusion: The Swedish results are not replicated in the United States. Both male and female US smokers appear to have higher quit rates for smoking than have their Swedish counterparts, despite greater use of smokeless tobacco in Sweden. Promoting smokeless tobacco for harm reduction in countries with ongoing tobacco control programmes may not result in any positive population effect on smoking cessation.

Symptoms of nicotine dependence in a cohort of Swedish youths: a comparison between smokers, smokeless tobacco users and dual tobacco users

AIMS To determine whether symptoms of nicotine dependence, addiction and withdrawal symptoms differ between exclusive smokers, exclusive snus (moist snuff) users and dual users. DESIGN A cross-sectional survey of a cohort subsample. Setting County of Stockholm, Sweden. PARTICIPANTS Current exclusive smokers (n = 466), exclusive snus users (n = 209) and dual users (n = 144), mean age 17.6 years. MEASUREMENTS Self-reported life-time experience of nicotine dependence and withdrawal symptoms in periods of discontinued tobacco use. Selected items from the modified Fagerstöm Tolerance Questionnaire (mFTQ), the Hooked on Nicotine Checklist (HONC) and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). FINDINGS The odds ratio of endorsing each of four mFTQ items as well as the HONC item investigating the risk of feeling addicted to tobacco was two to five-fold higher for exclusive snus users and for dual users compared to exclusive smokers. One DSM-IV item (difficult to refrain from use) was elevated among dual users compared to smokers. Dual users reported the highest prevalence of any withdrawal symptom in contrast to exclusive snus users, who reported a lower risk of withdrawal symptoms compared to exclusive smokers. CONCLUSIONS Smokeless tobacco users show symptoms of nicotine dependence at least as frequently as cigarette smokers. Symptoms of nicotine dependence and of withdrawal during quit attempts are particularly frequent in the subgroup of users who combine smokeless tobacco with smoking.

Stopping smokeless tobacco with varenicline: randomised double blind placebo controlled trial

Objective To assess the efficacy and safety of varenicline (a licensed cigarette smoking cessation aid) in helping users of smokeless tobacco to quit. Design Double blind, placebo controlled, parallel group, multicentre, randomised controlled trial. Setting Medical clinics (mostly primary care) in Norway and Sweden. Participants Men and women aged ≥18 who used smokeless tobacco at least eight times a day, with no abstinence period over three months within one year before screening, who wanted to quit all tobacco use. Participants were excluded if they used any other form of tobacco (except smokeless tobacco) or medication to stop smoking within three months of screening or had any pre-existing medical or psychiatric condition. Interventions Varenicline 1 mg twice daily (titrated during the first week) or placebo for 12 weeks, with 14 weeks’ follow-up after treatment. Main outcome measures The primary end point was the four week continuous abstinence rate at the end of treatment (weeks 9-12) confirmed with cotinine concentration. A secondary end point was continuous abstinence rate for weeks 9-26. Safety and tolerability were also evaluated. Results 431 participants (213 varenicline; 218 placebo) were randomised and received at least one dose of study drug. Participants’ demographics and baseline use of smokeless tobacco were similar (89% (189) and 90% (196), respectively, were men; mean age in both groups was 43.9; participants used smokeless tobacco products about 15 times a day, and about 80% first used smokeless tobacco within 30 minutes after awakening). Continuous abstinence rate at week 9-12 was higher in the varenicline group than the placebo group (59% (125) v 39% (85); relative risk 1.60, 95% confidence interval 1.32 to 1.87, P<0.001; risk difference 20%; number needed to treat 5). The advantage of varenicline over placebo persisted through 14 weeks of follow-up (continuous abstinence rate at week 9-26 was 45% (95) v 34% (73); relative risk 1.42, 1.08 to 1.79, P=0.012; risk difference 11%; number needed to treat 9). The most common adverse events in the varenicline group compared with the placebo group were nausea (35% (74) v 6% (14)), fatigue (10% (22) v 7% (15)), headache (10% (22) v 9% (20)), and sleep disorder (10% (22) v 7% (15)). Few adverse events led to discontinuation of treatment (9% (19) and 4% (9), respectively), and serious adverse events occurred in two (1%) and three (1%) participants, respectively. Conclusion Varenicline can help people to give up smokeless tobacco and has an acceptable safety profile. The response rate in the placebo group in this study was high, suggesting a population less resistant to treatment than smokers. Trial Registration NCT00717093.

Quitline in smoking cessation: A cost-effectiveness analysis

OBJECTIVES The cost-effectiveness of the Swedish quitline, a nation-wide, free of charge service, is assessed. METHODS The study was based on data of a sample of 1131 callers enrolled from February 1, 2000 to November 30, 2001. Outcome was measured as cost per quitter and cost per year of life saved. Cost per quitter was based on a calculation of the total cost of the quitline divided by the number of individuals who reported abstinence after 12 months. The cost per life year saved (LYS) was calculated by the use of data from the literature on average life expectancy for smokers versus quitters, the total cost of the quitline, and the cost of pharmacological treatment. RESULTS The number of smokers who used the quitline and reported abstinence after 1 year was 354 (31 percent). The accumulated number of life years saved in the study population was 2400. The cost per quitter was 1052-1360 USD, and the cost per life year saved was 311-401 USD. A sensitivity analysis showed that, for outcomes down to an abstinence rate of 20 percent, the cost per LYS rose modestly, from 311 to 482 USD. Discounting the cost per LYS showed the cost to be 135 USD for 3 percent and 283 USD for 5 percent. CONCLUSIONS The Swedish quitline is a cost-effective public health intervention compared with other smoking cessation interventions.

Changing patterns of tobacco use in a middle-aged population: the role of snus, gender, age, and education.

Background : In Sweden, the smoking prevalence has declined. In 2007, it was among the lowest in the industrialized world. A steady increase in the use of Swedish oral moist snuff, snus, has occurred in parallel. This development is neither solicited by authorities nor the medical establishment, but rather has occurred along with increased awareness of the dangers of smoking, and has been promoted by product development and marketing of snus. Objective : To evaluate time trends in patterns of tobacco use in northern Sweden during 1990–2007. Design : Cross-sectional (99,381 subjects) and longitudinal (26,867 subjects) data from the Västerbotten Intervention Programme (VIP) 1990–2007 were analyzed. All adults in Västerbotten County are invited to a VIP health examination at ages 40, 50, and 60 years, and until 1995 also 30 years. Smoking and use of snus were evaluated by gender, age and educational groups. Intermittent smoking was categorized as smoking. Results : From the period 1990–1995 to the period 2002–2007, smoking prevalence decreased from 26 to 16% among men and from 27 to 18% among women. The differences in prevalence increased between educational groups. The decline in smoking was less and the increase of snus use was greater among those with basic education. The use of snus among basic-educated 40-year-olds reached 35% among men and 14% among women during 2002–2007. Dual smoking and snus use increased among men and women with basic education. Smoking without snus use was more prevalent among women. Gender differences in total smoking prevalence (smoking only plus dual use) were small in all age groups, but increased among those with basic education reaching 7.3% during 2002–2007, with women being more frequent smokers. Smoking prevalences were similar among never, former and current snus users. Among the 30,000 former smokers, 38% of men and 64% of women had never used snus. Longitudinal data showed a decline in total tobacco use from baseline until follow-up and this was mainly due to a smoking cessation rate of < 1% a year. Snus use was started by 6.2% of the 30-year-old women (age at baseline), and this contributed to a stable prevalence of total tobacco use in this group. Seventy percent of baseline snus users still used snus at follow-up. Among smokers, 55% continued smoking, 12% of men and 7% of women switched to snus. Among those with dual tobacco use at baseline, a third of men and a fourth of women remained dual users 10 years later. Conclusion : There are increasing differences in tobacco use between educational groups. Higher smoking and snus use prevalence are found among those with basic education, and this is most pronounced in the younger group of this middle-aged population. In spite of a higher prevalence of smoking without snus use among women, total smoking prevalence is similar in men and women due to a higher prevalence of dual tobacco use, i.e. snus and cigarettes, among men. The increase in snus use is being paralleled by a slight increase in dual use and the smoking prevalence does not seem to be influenced by snus. This should be the subject of further studies and also have implications for tobacco control policies.

Increased mole fraction of arachidonic acid in bronchial phospholipids in patients with cystic fibrosis

The fatty acid pattern of the phospholipids in the bronchial secretion of patients with cystic fibrosis (CF) showed an increase of the mole fraction of arachidonic acid (AA) in most phospholipid classes compared to normals. Increase of AA in some classes was also found in patients with chronic bronchitis and in patients chronically colonized with Pseudomonas aeruginosa but in the diphosphatidylglycerol, lysophosphatidylethanolamine and sphingomyelin phospholipids, high fractions of AA was found exclusively in CF patients. Arachidonic acid was found to attain the highest ratios in CF in seven of the nine major bronchial phospholipids compared to the controls. There was no difference in the ratio saturated/unsaturated fatty acids between the CF patients and the control groups. A tendency towards unsaturation of the fatty acids in the bronchial secretion seems to be characteristic of infection and inflammation but AA appears to be more markedly increased in CF. Thus, the recorded changes may be characteristic for CF and not secondary to infection and/or inflammation in general, nor to P. aeruginosa colonization.

Are non-responders in a quitline evaluation more likely to be smokers?

BackgroundIn evaluation of smoking cessation programs including surveys and clinical trials the tradition has been to treat non-responders as smokers. The aim of this paper is to assess smoking behaviour of non-responders in an evaluation of the Swedish national tobacco cessation quitline a nation-wide, free of charge service.MethodsA telephone interview survey with a sample of people not participating in the original follow-up. The study population comprised callers to the Swedish quitline who had consented to participate in a 12 month follow-up but had failed to respond. A sample of 84 (18% of all non-responders) was included. The main outcome measures were self-reported smoking behaviour at the time of the interview and at the time of the routine follow-up. Also, reasons for not responding to the original follow-up questionnaire were assessed. For statistical comparison between groups we used Fischers exact test, odds ratios (OR) and 95% confidence intervals (CI) on proportions and OR.ResultsThirty-nine percent reported to have been smoke-free at the time they received the original questionnaire compared with 31% of responders in the original study population. The two most common reasons stated for not having returned the original questionnaire was claiming that they had returned it (35%) and that they had not received the questionnaire (20%). Non-responders were somewhat younger and were to a higher degree smoke-free when they first called the quitline.ConclusionTreating non-responders as smokers in smoking cessation research may underestimate the true effect of cessation treatment.

Smoking mothers and snuffing fathers: behavioural influences on youth tobacco use in a Swedish cohort

Objective: To analyse the influences of parental use of cigarettes and snus (the Swedish variety of smokeless tobacco) on offspring’s behaviour. Design: Prospective cohort study. Setting: The Stockholm County of Sweden. Subjects: 2232 adolescents recruited in the fifth grade (mean age 11.6 years) with follow up in the eighth grade. Main outcome measures: Self reported tobacco use (ever and current use of cigarettes and/or snus) in the eighth grade. Results: Parents’ tobacco use was associated with adolescents’ current use of cigarettes and snus (odds ratio (OR) 2.7, 95% confidence interval (CI) 1.8 to 3.9 if both parents used tobacco v neither parent). Mother’s cigarette smoking was associated with adolescents’ current exclusive smoking (OR 2.4, 95% CI 1.6 to 3.6). Father’s use of snus was associated with current exclusive use of snus among boys (OR 3.0, 95% CI 1.4 to 6.4), but not with current cigarette use. The overall prevalence of current smoking was lower among children whose fathers used snus than among those whose fathers smoked. Conclusions: Parental smoking, especially maternal smoking, enhances the risk of tobacco experimentation in youths, as does paternal use of smokeless tobacco. However, the transition to regular cigarette smoking is not likely to be affected by paternal use of smokeless tobacco. Contextual factors, in particular declining smoking trends and negative social acceptance of smoking, can explain most of these findings.