The influence of cigarette smoking on adult asthma outcomes.

Despite having a chronic respiratory disease, adults with asthma do not appear to selectively avoid smoking. We used data from a prospective cohort study of 865 adults, with asthma recruited from a large managed care organization after hospitalization for asthma. In this study, we analysed the association between cigarette smoking and asthma health outcomes, controlling for age, sex, race, educational attainment, household income, atopic history, and history of childhood asthma onset. Current smoking was associated with increased severity of asthma (mean increment, 1.36 points; 95% CI = 0.36, 2.36), worse asthma-specific quality of life (mean score increment, 5.49 points; 95% CI = 2.19, 8.78), and worse generic mental health status (mean score decrement, -4.57 points; 95% CI = -7.01, -2.12); p<.05 in all cases. Current smoking also was associated with a greater longitudinal risk of hospitalization for asthma (OR = 1.86, 95% CI = 1.03, 3.36). Our results suggest that the pubic health consequences of smoking, in terms of additional asthma morbidity, are considerable. Smoking is a modifiable risk factor for adverse asthma health outcomes. Public health interventions should focus on smoking reduction among adults with asthma.     

Belief about drug assignment and abstinence in treatment of cigarette smoking using nortriptyline.

This study assessed the relationship between beliefs about drug assignment and abstinence status in two treatment studies using nortriptyline hydrochloride as an adjunct to smoking cessation. Smokers (N = 345) drawn from two clinical trials were asked at the final follow-up (FFU) at 52 or 64 weeks whether they believed they had received active or placebo drug. Responses were obtained from 262 participants, or 76% of the sample. Biochemically verified abstinence was collected at end of treatment (EOT) and FFU. In both studies, participants were correct in guessing drug assignment. At FFU, belief about drug assignment was not related to abstinence for either active or placebo participants. Participants who received active drug and who were smoking at EOT were more likely to believe they had received placebo than active drug participants who were abstinent at EOT. We found no significant relationship between belief about drug and abstinence status for placebo participants at EOT. Baseline variables did not significantly predict correctness of drug identification. Participants who experienced drug side-effects not easily attributable to nicotine withdrawal were more likely to identify their drug assignment as nortriptyline. We conclude that experience during the active treatment period, including side-effects and treatment success, may be related to belief about drug assignment, that the field would be well served by at least two assessments of blindness in clinical trials, and that discrepancy between these findings and those regarding nicotine replacement therapy may be related to differences in dependent variables.     

A pilot study on voucher-based incentives to promote abstinence from cigarette smoking during pregnancy and postpartum.

We report results from a pilot study examining the use of vouchers redeemable for retail items as incentives for smoking cessation during pregnancy and postpartum. Of 100 study-eligible women who were still smoking upon entering prenatal care, 58 were recruited from university-based and community obstetric practices to participate in a smoking cessation study. Participants were assigned to either contingent or noncontingent voucher conditions. Vouchers were available during pregnancy and for 12 weeks postpartum. In the contingent condition, vouchers were earned for biochemically verified smoking abstinence. In the noncontingent condition, vouchers were earned independent of smoking status. Abstinence monitoring and associated voucher delivery was conducted daily during the initial 5 days of the cessation effort, gradually decreased to every other week antepartum, increased to once weekly during the initial 4 weeks postpartum, and then decreased again to every other week for the remaining 8 weeks of the postpartum intervention period. Contingent vouchers increased 7-day point-prevalence abstinence at the end-of-pregnancy (37% vs. 9%) and 12-week postpartum (33% vs. 0%) assessments. That effect was sustained through the 24-week postpartum assessment (27% vs. 0%), which was 12 weeks after discontinuation of the voucher program. Total mean voucher earnings across antepartum and postpartum were 397 US dollars (SD=414 US dollars) and 313 US dollars (SD=142 dollars) in the contingent and noncontingent conditions, respectively. The magnitude of these treatment effects exceed levels typically observed with pregnant and recently postpartum smokers, and the maintenance of effects through 24 weeks postpartum extends the duration beyond those reported previously.     

Cough following initiation of smoking abstinence.

Some clinicians and patients believe that cough and sputum production may transiently increase over the first weeks after smoking cessation and may in fact represent a barrier to successful quitting. The present study described changes in cough after an attempt to quit smoking cigarettes and determined patients' perceptions of how changes in cough affected their ability to maintain abstinence from smoking. Daily smokers already recruited for ongoing outpatient clinical trials of pharmacological aids to quit cigarette smoking were invited to complete self-report questionnaires about their cough for up to 6 weeks after their target quit date (TQD). Of the 176 subjects invited to participate, 112 completed the first assessment after the TQD. Of these, a total of 45 subjects maintained at least 1week of smoking abstinence at some point in the 6-week period (confirmed by carbon monoxide measurements). Two self-report measures found that cough declined steadily in abstinent smokers but was constant in a comparator group of continuing smokers (n = 36). For the 94 subjects who reported smoking at least one cigarette following the TQD, few reported that changes in cough affected their abstinence attempt. For three items asking about this area, the upper 95% confidence interval was no more than 10% for agreement that changes in cough posed any barrier to abstinence. We conclude that an initial increase in cough is unlikely to occur among relatively healthy smokers who stop smoking and that changes in cough do not represent a barrier to maintaining abstinence for most smokers.     

Public understanding of the illnesses caused by cigarette smoking.

A nationwide survey of 776 U.S. residents, divided approximately equally between teenagers and adults, smokers and nonsmokers, assessed public understanding of the illnesses caused by smoking. When respondents were asked what illnesses are caused by smoking, lung cancer was the only illness that could be identified by a clear majority of respondents. Roughly half mentioned emphysema. A much smaller percentage of respondents were able to mention any cardiovascular disease or any kind of cancer other than lung cancer. People also underestimated the death rate from lung cancer and overestimated survival duration. Only a minority realized that emphysema is incurable. Large portions of the sample said they knew only a little about the pain and suffering experienced by individuals with these illnesses. The results demonstrated that even though people recognize that smoking can lead to adverse health consequences, they do not have even a basic understanding of the nature and severity of these consequences.     

Errors in interpreting abstinence curves in studies of smoking cessation.

Articles on smoking cessation often present curves representing the percentage of smokers still abstinent over time. The purpose of this paper is to illustrate how common conclusions from inspecting these curves may be misleading because they are based on assumptions of which readers are not aware. For example, when active and control abstinence curves converge, this is often interpreted to indicate a diminution of treatment effect size over time. We use illustrative data to show that this interpretation is correct if one assumes a treatment has a constant additive effect; however, if one assumes treatment has a constant multiplicative effect, then converging curves can still indicate a constant treatment effect. Converging abstinence curves are also often interpreted to indicate that the rate of relapse is greater in the active than the control group. We illustrate that this interpretation is correct if one is interested in cumulative relapse rate and uses all subjects in the denominator; however, if one is interested in relapse over a discrete subperiod of time (e.g., immediately after treatment stops), and thus uses only those at risk for relapse, then converging curves can still indicate a constant relapse rate. When trials interpret abstinence curves, they should make clear whether they are assuming additive or multiplicative effects of treatment and are discussing overall or local relapse rates. They should also report both additive and multiplicative effect sizes.     

Craving, withdrawal, and smoking urges on days immediately prior to smoking relapse.

Rates of smoking relapse remain high, despite the wide availability of cessation aids. Presumably factors such as craving, withdrawal symptoms, and smoking urges are key contributors to relapse, but empirical support for this presumption is not conclusive and is complicated by the high variability in symptoms across individuals and time, as well as by the lack of an absolute symptom threshold for response. Data were analyzed from 137 female smokers, aged 18-40 years, who completed 30 days of a protocol for a longitudinal smoking cessation trial. Subjects were assigned a quit date and followed regardless of subsequent smoking status. At baseline, subjects completed written measures of nicotine craving, withdrawal symptoms, and smoking urges. They also completed these measures daily for 30 days, beginning on their quit date, Scores were standardized within subjects and graphed to identify temporal symptom patterns. A total of 26 women quit smoking and 111 relapsed (at least one cigarette puff). The intensity of subjects' craving, withdrawal, and smoking urges Factors 1 and 2 peaked on the day of relapse by an average of 1.4, 1.1, 1.2, and 1.1 standard deviations, respectively, with symptoms rising during the previous 2-5 days and dropping precipitously over the 2 days subsequent to relapse. Additionally, women who relapsed had higher absolute (unstandardized) symptom scores on their quit day than those who were abstinent for 30 days. These findings imply that escalation of withdrawal symptoms, craving, and smoking urges during a quit attempt may contribute to smoking relapse. Frequent symptom monitoring might be clinically important for relapse prevention.     

Associations between phenylthiocarbamide gene polymorphisms and cigarette smoking.

Phenotypic evidence indicates that the ability to taste the bitter compounds phenylthiocarbamide (PTC) and 6-n-propylthiouracil (PROP) may protect against cigarette smoking. In this study, PTC gene haplotypes were found to be associated with both the odds of being a smoker and the importance of cigarette taste as a smoking motive. Smokers (n = 384) and nonsmokers (n = 183) were genotyped for polymorphisms that affect taste sensitivity to PTC and PROP. The "taster" PAV haplotype, relative to the "nontaster" AVI haplotype, was predicted to be associated with reduced odds of being a smoker and lower taste motivation as measured by the Wisconsin Inventory of Smoking Dependence Motives-68 taste/sensory processes scale. The results did not support the predicted association between the PAV and AVI haplotypes and smoker odds, but the AAV haplotype, which confers intermediate PTC/PROP taste sensitivity, was associated with reduced smoker prevalence (49% vs. 70%), chi(2)(1, N = 567) = 10.392, p = .001. The predicted relationship between PAV and AVI and taste motivation was found, F(2, 348) = 3.303, p = .038. The results encourage further exploration of the role of taste/sensory processes in tobacco dependence.     

Effects of smoking abstinence, smoking cues and nicotine replacement in smokers with schizophrenia and controls.

The mechanisms underlying the low smoking cessation rates among smokers with schizophrenia (SS) are unknown. In this laboratory study, we compared the responses of 21 SS and 21 non-psychiatric controls (CS) to manipulations of 5-hour smoking abstinence, transdermal nicotine replacement (0 mg, 21 mg and 42 mg), and in vivo smoking cues. Results indicate that SS were more sensitive than CS to the effects of acute abstinence on carbon monoxide (CO) boost, but not more sensitive to the effects of abstinence on urge levels or withdrawal symptoms. SS and CS did not differ in urge response to in vivo smoking cues, but SS were less consistent in their reactions. These findings suggest that heightened sensitivity to the effects of abstinence on smoke intake may partially account for the low cessation rates experienced by SS, but other potential mechanisms should be explored using behavioral laboratory models.     

The influence of depressive symptoms on experimental smoking and intention to smoke in a diverse youth sample.

Numerous studies have shown associations between smoking and depression, but the generalizability of the relationship across ethnic groups remains unknown. The present study assessed the association between depression and smoking intention and experimentation among adolescents from four ethnic groups in the Los Angeles area-Chinese/Chinese American, Latino/Hispanic, Persian/Iranian, and White. Over 800 7th graders in the Los Angeles area completed measures of depressive symptoms, experimentation with smoking, intention to smoke, and sociodemographic covariates. Chinese/Chinese American students had the lowest levels of depressive symptoms, whereas Latinos/Hispanics had the highest levels. Latinos/Hispanics also were the most likely to intend to smoke in the next year and were the most likely to have started experimenting with cigarette smoking. Depressive symptoms were significantly associated with intention to smoke even after controlling for language use acculturation, socioeconomic status, gender, and ethnicity. The association between depressive symptoms and intention to smoke did not vary significantly across ethnic groups. These results indicate that the association between depressive symptoms and adolescent smoking generalizes across diverse ethnic groups.     

Does a failed quit attempt reduce cigarette consumption following resumption of smoking? The effects of time and quit attempts on the longitudinal analysis of self-reported cigarette smoking intensity.

California Tobacco Survey respondents were asked the intensity of their cigarette smoking 1 year previously and at the time of the survey. Respondents reported a generally lower smoking intensity at survey time compared with 1 year previously. Multivariable statistical models on the change in smoking intensity in the past year were fitted to assess the effects of low-tar cigarette use, a quit attempt in the past year, smoking intensity 1 year previously, and demographic variables (age, education, income, and race). The most important predictor of change in intensity was the intensity 1 year previously. The next most important predictor was whether a quit attempt had been made in the previous year. The demographic variables also were found to have a significant effect, although their effects were of smaller magnitude. Low-tar cigarette use was not a significant predictor of change in intensity in multivariable analysis. The effect of a quit attempt on the reduction in intensity of smoking suggests that periods of cessation may reduce the intensity of smoking and the level of addiction for several months following relapse. Consequently, it may be important to control for cessation activity in studies comparing exposures from conventional tobacco products to exposures from new products that purport to offer lower harm.     

Ethnic-by-gender differences in cigarette smoking among Asian and Pacific Islanders.

We examined the interaction between ethnicity and gender in predicting the likelihood of having ever smoked (vs. having never smoked) and being a current smoker (vs. being a former smoker) and in predicting years spent as a regular smoker. These relationships were examined while controlling for the possible confounding effects of sociodemographics, psychosocial factors, and chronic medical conditions. The analysis examined cross-sectional data from 1,158 people of Native Hawaiian, Filipino, Japanese, and White ethnic ancestry, finding large ethnic and gender-ethnic differences in the prevalence of former and current smoking. Multiple regression analyses showed significant gender x ethnicity interactions in predicting the likelihood of having ever smoked but not in the likelihood of being a current smoker (vs. having quit) or in the duration of years spent smoking. The results of the present study have important implications for smoking prevention programs among men and women in three distinct Asian and Pacific Islander ethnic groups.     

Smoke constituent exposure and smoking topography of adolescent daily cigarette smokers.

Adolescent smoking prevalence is a major health concern, with 24.4% reporting smoking in the past 30 days and 15.8% considered daily smokers. The purpose of this study was to characterize biobehavioral nicotine dependence, smoke constituent exposure and smoking topography in adolescent daily smokers. Relationships among biological markers of nicotine dependence (nicotine boost, carbon monoxide [CO] boost and cotinine levels) with existing self-report measures (modified Fagerstr?m Tolerance Questionnaire [mFTQ] and the motivations for smoking scale) were examined. Gender differences were characterized. Fifty adolescents 13-18 years old were recruited for the study, 50% female. CO, plasma nicotine levels pre- and postcigarette, cotinine, and smoking topography were measured during a smoking bout with participant's usual cigarette. Average CO boost, pre- to postcigarette was 7.2 + 3.6 ppm, baseline cotinine level averaged 224.0 +/- 169.6 ng/ml and nicotine boost averaged 23.4 +/- 21.7 ng/ml. Mean puffs per cigarette was 14.2 +/- 6.3. Males had significantly higher total puff volumes, but similar smoke constituent exposure to females, and higher handling of cigarettes as smoking motive. In regression analysis, 35% of variance in tobacco use, as indicated by baseline cotinine concentration, was explained by maximum puff duration, postcigarette CO level, and nicotine dependence, as measured by the mFTQ. Results indicated adolescents had considerable smoke constituent exposure and nicotine dependence suggesting the importance of appropriate smoking cessation treatment.     

淫羊藿滤嘴降低卷烟烟气中的有害成分研究

为研究淫羊藿滤嘴降低卷烟烟气中有害成分的作用,采用对比分析方式,先用吸烟机捕集卷烟烟气,收集主流烟气的总粒相物,再用超声波萃取方法对收集烟气粒相物的剑桥滤片进行萃取,分析烟气中的常规成分（烟碱、焦油、水分）,最后用GC/MS定量、定性分析烟气化学成分。结果表明,与空白样对比,淫羊藿滤嘴对烟碱、总粒相物、焦油量有降低作用,且分别降低了8.60%、10.86%和14.97%;对烟气中的一些有害成分,特别是促癌、致癌的酚类物质的截留效果比较明显,苯酚降低56.6%,对甲苯酚降低32.8%,4-乙基间苯二酚降低50%,2,2＇-亚甲基双-（4-甲基-6-叔丁基苯酚）降低29.0%。添加淫羊藿的卷烟滤棒能有效降低烟气中的有害成分,符合＂中式卷烟＂的发展方向。     

抽吸方式对卷烟主流烟气中氢氰酸释放量的影响

为考察不同抽吸方式对卷烟主流烟气中氢氰酸(HCN)释放量的影响,采用ISO、Massachusetts和Health Canada 3种抽吸方式分别抽吸了15种市售卷烟,采用连续流动法测定了主流烟气中的HCN释放量.研究表明:与ISO方案相比,采用Massachusetts或Health Canada深度抽吸方式,HCN释放量均有显著提高;抽吸方式的改变对低焦油卷烟、高滤嘴通风率的卷烟的HCN释放量影响更为显著.     

Western media's influence on Egyptian adolescents' smoking behavior: the mediating role of positive beliefs about smoking.

Western media has been implicated as an adolescent smoking risk factor in numerous Western studies, but little research has investigated that influence on adolescents from developing Arab countries. One such country is Egypt, which has the highest rate of smoking in the Arab world. An estimated 34% of Egyptians are daily smokers, 4% of whom are under the age 15 years and 0.6% of whom are under the age 10. The present study investigated the association between exposure and receptivity to Western media, positive beliefs about smoking, and Egyptian adolescents' smoking behavior. A school-based cross-sectional survey of 1,930 Egyptian adolescents in 7th, 9th, and 12th grades, from randomly selected schools in Alexandria, Egypt, was conducted in May 2003. Self-reported smoking behaviors, demographics, psychosocial factors, and exposure to Western and pro-tobacco media were assessed. Controlling for demographics, psychosocial smoking risk factors, and pro-tobacco media exposure, we found that Western media exposure was positively associated with ever-smoking across genders and 30-day smoking among adolescent males only. Positive beliefs about smoking partially mediated this association among ever-smokers and completely mediated it among 30-day male smokers. The results indicate that the influence of Western media on Egyptian adolescents' smoking behavior is at least partially mediated by its influence in increasing adolescents' positive beliefs about smoking and consequently their smoking behavior. Regulation of the glamorization of smoking behavior in Western media and correction of the erroneous perception of positive beliefs about smoking among adolescents is necessary to help curb the rising smoking epidemic in Egypt.