Smoking in China: findings of the 1996 National Prevalence Survey

Overexpression and small molecule-triggered downregulation of CIP2A in lung cancer

Background

Lung cancer is the leading cause of cancer deaths worldwide, with a five-year overall survival rate of only 15%. Cancerous inhibitor of PP2A (CIP2A) is a human oncoprotein inhibiting PP2A in many human malignancies. However, whether CIP2A can be a new drug target for lung cancer is largely unclear.

Methodology/Principal Findings

Normal and malignant lung tissues were derived from 60 lung cancer patients from southern China. RT-PCR, Western blotting and immunohistochemistry were used to evaluate the expression of CIP2A. We found that among the 60 patients, CIP2A was undetectable or very low in paratumor normal tissues, but was dramatically elevated in tumor samples in 38 (63.3%) patients. CIP2A overexpression was associated with cigarette smoking. Silencing CIP2A by siRNA inhibited the proliferation and clonogenic activity of lung cancer cells. Intriguingly, we found a natural compound, rabdocoetsin B which is extracted from a Traditional Chinese Medicinal herb Rabdosia coetsa, could induce down-regulation of CIP2A and inactivation of Akt pathway, and inhibit proliferation and induce apoptosis in a variety of lung cancer cells.

Conclusions/Significance

Our findings strongly indicate that CIP2A could be an effective target for lung cancer drug development, and the therapeutic potentials of CIP2A-targeting agents warrant further investigation.

Paternal smoking and risk of childhood acute lymphoblastic leukemia: systematic review and meta-analysis

Objective. To investigate the association between paternal smoking and childhood acute lymphoblastic leukemia (ALL). Method. We identified 18 published epidemiologic studies that reported data on both paternal smoking and childhood ALL risk. We performed a meta-analysis and analyzed dose-response relationships on ALL risk for smoking during preconception, during pregnancy, after birth, and ever smoking. Results. The summary odds ratio (OR) of childhood ALL associated with paternal smoking was 1.11 (95% Confidence Interval (CI): 1.05-1.18, I(2) = 18%) during any time period, 1.25 (95% CI: 1.08-1.46, I(2) = 53%) preconception; 1.24 (95% CI: 1.07-1.43, I(2) = 54%) during pregnancy, and 1.24 (95% CI: 0.96-1.60, I(2) = 64%) after birth, with a dose-response relationship between childhood ALL and paternal smoking preconception or after birth. Conclusion. The evidence supports a positive association between childhood ALL and paternal ever smoking and at each exposure time period examined. Future epidemiologic studies should assess paternal smoking during well-defined exposure windows and should include biomarkers to assess smoking exposure and toxicological mechanisms.

Influence of polymorphisms in MTHFR 677 C→T, TYMS 3R→2R and MTR 2756 A→G on NSCLC risk and response to platinum-based chemotherapy in advanced NSCLC

AIMS

Genetic factors may contribute to individual differences in cancer susceptibility, drug efficacy and toxicity. This study was designed to investigate the effects of the polymorphisms of methylenetetrahydrofolate reductase 677 C→T (MTHFR 677 C→T), thymidylate synthase (TYMS 3R→2R),and methionine synthase 2756 A→G (MTR 2756 A→G) on the risk of lung cancer and response to platinum-based chemotherapy in advanced non-small-cell lung cancer (NSCLC).

MATERIALS & METHODS

We conducted a case-control study involving 438 NSCLC cases (including 101 follow-up cases) and 641 healthy controls in North China.

RESULTS & CONCLUSION

Using a genetic model analysis, the polymorphism MTHFR 677 C→T showed a significantly increased risk for NSCLC in women but not in men, which was observed in the codominant model (CT vs CC adjusted odds ratio [OR] = 2.46; 95% confidence interval [CI]: 1.37-4.42; p = 0.003; TT vs CC adjusted OR: 2.04; 95% CI: 1.09-3.81; p = 0.03) and the dominant model (CT + TT vs CC adjusted OR: 2.30; 95% CI: 1.31-4.05; p = 0.004). In addition, we found that patients with the MTHFR 677 TT genotype showed a better response to platinum-based chemotherapy in the recessive model (TT vs CT + CC adjusted OR: 0.24; 95% CI: 0.09-0.68; p = 0.007), the generalized OR was 0.44 (0.22-0.88; p = 0.04). There were no significant associations of the polymorphisms of TYMS 3R→2R or MTR 2756 A→G with the risk of NSCLC or response to platinum-based chemotherapy in advanced NSCLC in any genetic model. Our results suggest that genetic polymorphisms of MTHFR 677 C→T may contribute to NSCLC development in Chinese women and could also influence treatment response for advanced NSCLC patients with platinum-based chemotherapy. Further studies with larger sample sizes are required to validate this association.

Associations of CYP2A6 genotype with smoking behaviors in southern China

AIMS

To investigate the association of CYP2A6 genetic polymorphisms with smoking-related phenotypes in Chinese smokers.

DESIGN

Case-only genetic association study.

SETTING

Southern China.

PARTICIPANTS

A total of 1328 Han Chinese smokers who participated in a community-based chronic disease screening project in Guangzhou and Zhuhai from 2006 to 2007.

MEASUREMENTS

All participants answered a structured questionnaire about socio-demographic status and smoking behaviors and informative alleles were genotyped for the cytochrome P450 2A6 (CYP2A6) gene (CYP2A6*4,*5,*7,*9 and *10).

FINDINGS

The frequencies of CYP2A6*4, *5, *7, *9 and *10 alleles were 8.5, 1.2, 6.3, 13.5 and 2.4%, which corresponded to 48.9, 15.4, 24.2 and 11.5% of participants being classified as normal, intermediate, slow and poor metabolizers, respectively. Multivariate analyses in male smokers demonstrated that compared with normal metabolizers, poor metabolizers reported smoking fewer cigarettes per day [adjusted odds ratio (OR) = 0.49; 95% confidence interval (CI): 0.32-0.76], started smoking regularly later in life (adjusted OR = 1.55; 95% CI: 1.06-2.26) and, among former smokers, reported smoking for a shorter duration prior to quitting (adjusted OR = 0.33; 95% CI: 0.12-0.94). However, poor metabolizers were less likely to quit smoking and remain abstinent than normal metabolizers (adjusted OR = 0.54; 95% CI: 0.34-0.86).

CONCLUSIONS

Reduced metabolism function of cytochrome P450 2A6 in smokers appears to be associated with fewer cigarettes smoked, later initiation of smoking regularly, shorter smoking duration and lower likelihood of smoking cessation.

Smoking and alcohol drinking increased the risk of esophageal cancer among Chinese men but not women in a high-risk population

Although the association for esophageal cancer with tobacco smoking and alcohol drinking has been well established, the risk appears to be less strong in China. To provide more evidence on the effect of smoking and alcohol consumption with esophageal cancer in China, particularly among Chinese women, a population-based case–control study has been conducted in Jiangsu, China, from 2003 to 2007. A total of 1,520 cases and 3,879 controls were recruited. Unconditional multivariate logistic regression analysis was applied. Results showed that the odds ratio (OR) and confidence interval (CI) for ever smoking and alcohol drinking were 1.57 (95% CI: 1.34–1.83) and 1.50 (95% CI: 1.29–1.74). Dose–response relationships were observed with increased intensity and longer duration of smoking/drinking. Risk of smoking and alcohol drinking at the highest joint level was 7.32 (95% CI: 4.58–11.7), when compared to those never smoked and never drank alcohol. Stratifying by genders, smoking and alcohol drinking increased the risk among men with an OR of 1.74 (95% CI: 1.44–2.09) and 1.76 (95% CI: 1.48–2.09); however, neither smoking nor alcohol consumption showed a significant association among women. In conclusion, smoking and alcohol drinking were associated with esophageal cancer risk among Chinese men, but not among Chinese women.

The use of cessation assistance among smokers from China: Findings from the ITC China Survey

BACKGROUND

Stop smoking medications significantly increase the likelihood of smoking cessation. However, there are no population-based studies of stop-smoking medication use in China, the largest tobacco market in the world. This study examined stop-smoking medication use and its association with quitting behavior among a population-based sample of Chinese smokers.

METHODS

Face-to-face interviews were conducted with 4,627 smokers from six cities in the ITC China cohort survey. Longitudinal analyses were conducted using Wave 1 (April to August, 2006) and Wave 2 (November 2007 to January 2008).

RESULTS

Approximately 26% of smokers had attempted to quit between Waves 1 and 2, and 6% were abstinent at 18-month follow-up. Only 5.8% of those attempting to quit reported NRT use and NRT was associated with lower odds of abstinence at Wave 2 (OR = 0.11; 95%CI = 0.03-0.46). Visiting a doctor/health professional was associated with greater attempts to quit smoking (OR = 1.60 and 2.78; 95%CI = 1.22-2.10 and 2.21-3.49 respectively) and being abstinent (OR = 1.77 and 1.85; 95%CI = 1.18-2.66 and 1.13-3.04 respectively) at 18-month follow-up relative to the smokers who did not visit doctor/health professional.

CONCLUSIONS

The use of formal help for smoking cessation is low in China. There is an urgent need to explore the use and effectiveness of stop-smoking medications in China and in other non-Western markets.

Health knowledge and perception of risks among Chinese smokers and non-smokers: findings from the Wave 1 ITC China Survey

BACKGROUND

Awareness of health risks of smoking is strongly associated with smoking behaviour. However, there are no population-based studies of smoking-related health knowledge in China.

OBJECTIVE

The aim of current study was to use a population-based sample from the International Tobacco Control China Wave 1 survey to examine variations between current, former and never smokers' health knowledge about smoking and the impact of health knowledge awareness on smokers' intention to quit.

METHODS

A face-to-face interview was conducted with 5986 adult smokers and non-smokers from six cities in China. Respondents were asked whether they believed smoking causes heart disease, stroke, impotence, lung cancer, emphysema, stained teeth, premature ageing in smokers and lung cancer in non-smokers. Current smokers were also asked additional questions on how smoking affects their current and future health as well as whether they had plans to quit smoking and if they believe they would have health benefit from quitting.

FINDINGS

The overall awareness of health risks of smoking in China was low compared to developed countries. Current smokers in China were less likely than non-smokers and former smokers to acknowledge the consequences of smoking. Current smokers who were more aware of the health consequences of smoking were more likely to intend to quit smoking.

CONCLUSION

These findings highlight the need to increase awareness about the health effects of smoking in China, particularly among current smokers to increase quitting.

Differences of smoking knowledge, attitudes, and behaviors between medical and non-medical students

BACKGROUND

Previous studies in the world reported inconsistent results about the relationship of medical professional education with medical students' smoking behaviors, and no similar research had been published in China.

PURPOSE

This paper aims to explore whether the differences of smoking-related knowledge, attitudes, and behaviors existed between medical and non-medical undergraduate students.

METHODS

Eight thousand one hundred thirty-eight undergraduate students sampled from a university in Guangzhou were investigated with a self-administered structured questionnaire about their smoking-related knowledge, attitude and behaviors, and other relevant factors. General linear model and multinomial logistic regression were conducted to test the differences in smoking-related knowledge, attitude, and behaviors between medical and non-medical students while controlling for potential confounding variables.

RESULTS

There was no difference in smoking-related knowledge scores between medical and non-medical freshmen, but medical sophomores and juniors had higher scores of smoking-related knowledge than their non-medical counterparts. The medical sophomores had higher mean score of attitudes towards smoking than non-medical ones. Before entering university, the difference in the prevalence of experimental and regular smoking between medical and non-medical college students was not significant. After entering university, in contrast, the overall prevalence of regular smoking was significantly higher among male non-medical college students than among male medical students. Stratified by current academic year, this difference was significant only among male sophomores.

CONCLUSIONS

Medical students have higher smoking-related knowledge, stronger anti-smoking attitude, and lower prevalence of regular smoking than non-medical college students of similar age, which may be associated with medical professional education.

Environmental tobacco smoke in relation to bladder cancer risk--the Shanghai bladder cancer study [corrected]

BACKGROUND

Environmental tobacco smoke (ETS) contains tobacco carcinogens. Hepatic cytochrome P450 (CYP) 1A2 and N-acetyltransferase (NAT2) are important isoenzymes in activation and detoxification, respectively, of tobacco carcinogens. Data on ETS and bladder cancer risk are sparse.

METHODS

We examined the effects of ETS alone and combined with NAT2/CYP1A2 on bladder cancer risk among lifelong-nonsmokers in a case-control study involving 195 patients and 261 controls in Shanghai, China. A comprehensive history of ETS exposure was determined through in-person interviews while CYP1A2 and NAT2 phenotypes by a caffeine-based urinary assay.

RESULTS

ETS exposure was related to an overall statistically nonsignificant 38% increased bladder cancer risk. The risk increased with increasing number of cigarettes smoked by household members or number of hours per day at workplace where coworkers smoked. Compared with no ETS exposure, subjects living with smoking parents during childhood had an OR of 2.43 (95% CI = 0.99-5.96) for bladder cancer. When all ETS sources were combined, the risk increased with increasing total ETS score (P(trend) = 0.03). The OR for high versus nil ETS exposure was 3.00 (95% CI = 1.24-7.26). The increased risk with ETS was mainly seen among individuals possessing a CYP1A2 high efficiency and/or a NAT2 slow acetylation phenotype (P(trend) = 0.04).

CONCLUSIONS

ETS was associated with an increased bladder cancer risk for lifelong-nonsmokers. The association was stronger for people possessing the at-risk phenotypes of CYP1A2 and/or NAT2.

IMPACT

Reducing exposure to ETS for children and genetically more susceptible individuals could be more effective for bladder cancer prevention.

Tobacco use among the elderly: a systematic review and meta-analysis

The aim of this study was to combine the results of identified surveys on the prevalence of tobacco use in old age to estimate world prevalence of tobacco use and possible factors related to such behavior among the elderly. The literature search included electronic databases such as MEDLINE, LILACS, and Biological Abstracts, hand-searching of specialist journals and cited reference searches. The combined global prevalence was estimated using the random effects model. The total number of elderly subjects included in all surveys was 140,058, with data available from all the continents. Overall prevalence of tobacco use was 13% in both genders (22% male and 8% female). The prevalence rates were heterogeneous among surveys and were associated with smoking definition, questionnaire application, and country economic status. Few epidemiological studies assessed tobacco use among the elderly. A higher prevalence rate of tobacco use in males who live in higher income countries could be found, although additional evidence regarding elderly samples is still required.

Community based integrated intervention for prevention and management of chronic obstructive pulmonary disease (COPD) in Guangdong, China: cluster randomised controlled trial

OBJECTIVE

To evaluate the effects of a community based integrated intervention for early prevention and management of chronic obstructive pulmonary disease (COPD) in China.

DESIGN

Cluster randomised controlled trial.

SETTING

Eight healthcare units in two communities.

PARTICIPANTS

Of 1062 people aged 40-89, 872 (101 with COPD and 771 without COPD) who fulfilled the inclusion and exclusion criteria were allocated to the intervention or the usual care programmes.

INTERVENTION

Participants randomly assigned to integrated intervention (systematic health education, intensive and individualised intervention, treatment, and rehabilitation) or usual care.

MAIN OUTCOME MEASURES

Annual rate of decline in forced expiratory rate in one second (FEV(1)) before use of bronchodilator.

RESULTS

Annual rate of decline in FEV(1) was significantly lower in the intervention community than the control community, with an adjusted difference of 19 ml/year (95% confidence interval 3 to 36) and 0.9% (0.1% to 1.8%) of predicted values (all P<0.05), as well as a lower annual rate of decline in FEV(1)/FVC (forced vital capacity) ratio (adjusted difference 0.6% (0.1% to 1.2%) P=0.029). There were also higher rates of smoking cessation (21% v 8%, P<0.004) and lower cumulative death rates from all causes (1% v 3%, P<0.009) in the intervention community than in the control community during the four year follow-up. Improvements in knowledge of COPD and smoking hazards, outdoor air quality, environmental tobacco smoke, and working conditions were also achieved (all P<0.05). The difference in cumulative incidence rate of COPD (both around 4%) and cumulative death rate from COPD (2% v 11%) did not reach significance between the two communities.

CONCLUSIONS

A community based integrated intervention can have a significant impact on the prevention and management of COPD, mainly reflected in the annual rate of decline in FEV(1).

TRIAL REGISTRATION

Chinese Clinical Trials Registration (ChiCTR-TRC-00000532).

Workplace smoking policies and their association with male employees' smoking behaviours: a cross-sectional survey in one company in China

OBJECTIVES

The present work sought to evaluate different worksite smoking control policies and their associations with employees' smoking behaviours and attitudes among Chinese male workers.

METHODS

This was a cross-sectional survey with a self-administered standardised questionnaire, conducted among seven production workplaces of one multinational company in Shanghai in 2008. In total, 1043 male workers were involved. Current smoking prevalence, daily cigarette consumption, quitting intention and their potential association with workplace smoking control policies (smoke free or restricted smoking) were measured.

RESULTS

Current smoking prevalence in workplaces where smoke-free policies had been imposed for 3 years was 55.5%, about 18% lower than in workplaces that only restricted smoking. Smokers in smoke-free workplaces also smoked 3.4 cigarettes less per day, made more quit attempts, were more confident of successfully quitting and more willing to accept a company sponsored cessation programme. Those patterns declined or were not found among the workplaces where smoking control policies had been imposed for 10 years. Smoker quitting intentions were not associated with workplace smoking policies regardless of the duration of the policies imposed.

CONCLUSIONS

A smoke-free workplace policy was found to have a significant association with lower smoking prevalence and daily cigarette consumption, but not with employee quitting intentions. Restrictive smoking policies had no impact on employee smoking behaviours. The impact of workplace smoking control policies may vary over time.

Prenatal environmental tobacco smoke exposure and early childhood body mass index

Maternal smoking during pregnancy is associated with increased risk of childhood overweight body mass index (BMI). Less is known about the association between prenatal secondhand tobacco smoke (SHS) exposure and childhood BMI. We followed 292 mother-child dyads from early pregnancy to 3 years of age. Prenatal tobacco smoke exposure during pregnancy was quantified using self-report and serum cotinine biomarkers. We used linear mixed models to estimate the association between tobacco smoke exposure and BMI at birth, 4 weeks, and 1, 2 and 3 years. During pregnancy, 15% of women reported SHS exposure and 12% reported active smoking, but 51% of women had cotinine levels consistent with SHS exposure and 10% had cotinine concentrations indicative of active smoking. After adjustment for confounders, children born to active smokers (self-report or serum cotinine) had higher BMI at 2 and 3 years of age, compared with unexposed children. Children born to women with prenatal serum cotinine concentrations indicative of SHS exposure had higher BMI at 2 (mean difference [MD] 0.3 [95% confidence interval -0.1, 0.7]) and 3 (MD 0.4 [0, 0.8]) years compared with unexposed children. Using self-reported prenatal exposure resulted in non-differential exposure misclassification of SHS exposures that attenuated the association between SHS exposure and BMI compared with serum cotinine concentrations. These findings suggest active and secondhand prenatal tobacco smoke exposure may be related to an important public health problem in childhood and later life. In addition, accurate quantification of prenatal secondhand tobacco smoke exposures is essential to obtaining valid estimates.

Cardiovascular disease risk factors are highly prevalent in the office-working population of Nanjing in China

OBJECTIVE

To establish a profile of the modifiable cardiovascular disease (CVD) risk factors in the office-working population of Nanjing, China.

BACKGROUND

With increasing modernization in China, CVD is now common among Chinese. Relevant information on the prevalence of CVD risk factors in China is, however, limited.

METHODS

We recruited 2648 office working people aged 23-79 years without history of CVD or diabetes from 7 work units of Nanjing during the years 2003 to 2005. Information from a self-reported questionnaire on lifestyle, physical examination, fasting blood for lipid profiles, and a 75-gram oral glucose tolerance test (OGTT) were obtained from each participant. We analyzed the following 7 CVD risk factors: smoking, inadequate physical activity, unhealthy dietary habit, obesity, hypertension, dyslipidemia, and hyperglycemia.

RESULTS

The whole study population had an average of 2.8 risk factors, while 95.6%, 79.4% and 55.6% of them had respectively ≥ 1, ≥ 2 and ≥ 3 of the 7 CVD risk factors. Men had a higher proportion of smoking, hypertension, dyslipidemia, hyperglycemia, but lower in light physical activity compared with women. Number of CVD risk factors increased with age. Although risk factors in men were more common than women, they increased alarmingly in postmenopausal women.

CONCLUSIONS

CVD risk factors are common in office-working people in Nanjing, China. Effective interventions and treatment against risk factors should be adopted in the high risk population, which may greatly reduce the future burden of CVD in the Chinese population.

Beliefs about the relative harm of "light" and "low tar" cigarettes: findings from the International Tobacco Control (ITC) China Survey

BACKGROUND

Many smokers in Western countries perceive "light" or "low tar" cigarettes as less harmful and less addictive than "regular" or "full flavoured" cigarettes. However, there is little research on whether similar perceptions exist among smokers in low and middle incomes, including China.

OBJECTIVE

To characterise beliefs about "light" and "low tar" cigarettes among adult urban smokers in China.

METHODS

We analysed data from Wave 1 of the ITC China Survey, a face-to-face household survey of 4732 adult Chinese smokers randomly selected from six cities in China in 2006. Households were sampled using a stratified multistage design.

FINDINGS

Half (50.0%) of smokers in our sample reported having ever tried a cigarette described as "light," "mild" or "low tar". The majority of smokers in our sample (71%) believed that "light" and/or "low tar" cigarettes are less harmful compared to "full flavoured" cigarettes. By far the strongest predictor of the belief that "light" and/or "low tar" cigarettes are less harmful was the belief that "light" and/or "low tar" cigarettes feel smoother on the respiratory system (p<0.001, OR=53.87, 95% CI 41.28 to 70.31).

CONCLUSION

Misperceptions about "light" and/or "low tar" cigarettes were strongly related to the belief that these cigarettes are smoother on the respiratory system. Future tobacco control policies should go beyond eliminating labelling and marketing that promotes "light" and "low tar" cigarettes by regulation of product characteristics (for example, additives, filter vents) that reinforce perceptions that "light" and "low tar" cigarettes are smoother on the respiratory system and therefore less harmful.

Individual-level factors associated with intentions to quit smoking among adult smokers in six cities of China: findings from the ITC China Survey

BACKGROUND

Over 350 million smokers live in China, and this represents nearly one-third of the smoking population of the world. Smoking cessation is critically needed to help reduce the harms and burden caused by smoking-related diseases. It is therefore important to identify the determinants of quitting and of quit intentions among smokers in China. Such knowledge would have potential to guide future tobacco control policies and programs that could increase quit rates in China.

OBJECTIVE

To identify the correlates of intentions to quit smoking among a representative sample of adult smokers in six cities in China.

METHODS

Data from wave 1 (2006) of the International Tobacco Control (ITC) Policy Evaluation Project China Survey, a face-to-face survey of adult Chinese smokers in six cities: Beijing, Shenyang, Shanghai, Changsha, Guangzhou and Yinchuan, was analysed. Households were sampled using a stratified multistage design. About 800 smokers were surveyed in each selected city (total n=4815).

RESULTS

Past quit attempts, duration of past attempts, Heaviness of Smoking Index (HSI), outcome expectancy of quitting, worry about future health and overall opinion of smoking were found to be independently associated with intentions to quit smoking, but demographic characteristics were not.

CONCLUSIONS

The determinants of quit intentions among smokers in China are fairly similar to those found among smokers in Western countries, despite the fact that interest in quitting is considerably lower among Chinese smokers. Identifying the determinants of quit intentions provides possibilities for shaping effective policies and programs for increasing quitting among smokers in China.

[Physicians' role in advancing tobacco control in China]

中国已经批准了烟草控制框架公约（Framework Convention on Tobacco Control, FCTC），并致力于执行烟草控制方案，以对抗烟草使用带来的大量不良健康和经济后果。医生需要在这场斗争中像其它国家，如澳大利亚等实施严厉烟草控制政策的国家一样，发挥主导作用。目前中国的问题包括医生自身的吸烟状况及其对患者影响作用的低估，这意味着他们潜在的积极作用远未实现。医生在烟草控制中责无旁贷。首先应从他们自身的戒烟等行为和做法开始，如果医生为吸烟者，则应戒烟，并指导患者及患者家属不吸烟。提倡医院和医疗机构无烟，亦为医生的首要任务。作为人们试图改善自身健康状况和接受疾病治疗的医疗中心，允许吸烟的行为是完全不合理的。

责任亦在于医生工作的机构和代表医生的专业团体机构，应为医生提供有助于控制他们自己以及患者烟草使用的信息、培训和支持。

Paternal smoking and breastfeeding in Xinjiang, PR China

A cohort of 1088 couples in Xinjiang, PR China, were recruited to study infant feeding practices and paternal smoking. Mothers were interviewed in hospital and at 0.5, 1.5, 2.5, 3.5, 4.5, and 6 months. Survival analysis was used to calculate breastfeeding rates in smokers and nonsmokers. The paternal smoking rate was 64.8% and maternal smoking rate 1.7% (P < .01). The rates for any breastfeeding in the smoking group were significantly lower than in the nonsmoking group from 3.5 months to 6 months (P < .05). The rates for exclusive breastfeeding in the paternal smoking group were lower than in the nonsmoking group from discharge to 6 months (P < .05). The median duration of exclusive breastfeeding in the paternal smoking group was shorter than in the nonsmoking group. Paternal smoking was a risk factor for stopping any breastfeeding (hazard risk, 1.84; 95% confidence interval, 1.11-3.04) and exclusive breastfeeding (hazard risk, 1.33; 95% CI, 1.09-1.64) compared with nonsmokers.

Paternal smoking and childhood overweight: evidence from the Hong Kong "Children of 1997"

OBJECTIVE

This study examined, in a non-Western sociohistorical context, whether prenatal or postnatal secondhand smoke (SHS) exposure for children of nonsmoking mothers was associated with higher childhood BMI, and it clarified whether the observed associations were biologically mediated or socioeconomically confounded.

METHODS

A total of 6710 and 6519 children of nonsmoking mothers (N = 7924) with BMI data at approximately 7 and approximately 11 years, respectively, from a population-representative (N = 8327), Hong Kong Chinese birth cohort ("Children of 1997"), born in April or May 1997, were included in the analysis.

RESULTS

Compared with no SHS exposure, daily paternal smoking increased mean BMI z scores, but not height, at 7 years (difference: 0.10 [95% confidence interval: 0.02-0.19]) and at 11 years (difference: 0.16 [95% confidence interval: 0.07-0.26]), with adjustment for gender, birth order, socioeconomic position, mother's place of birth, breastfeeding, serious morbidity, and pubertal status.

CONCLUSIONS

Our findings, although preliminary, suggest that the association of paternal smoking with child overweight might be biologically mediated. Given the known harms of smoking, reducing SHS exposure from conception as a precautionary action for childhood overweight might be warranted.

Smoking knowledge, attitudes, and behaviors among rural-to-urban migrant women in Beijing, China

BACKGROUND

China has the largest population of cigarette smokers worldwide; surveys suggest rising prevalence among young women. Migratory lifestyles may confer increased susceptibility.

OBJECTIVES

we aimed to understand how migration relates to smoking among young women.

METHODS

we implemented a cross-sectional behavioral survey of rural-to-urban Chinese women (n = 206) working in restaurants and commercial sex venues, assessing smoking attitudes, behaviors, and health-risk knowledge.

RESULTS

rates of ever smoking and current smoking among restaurant workers were high compared with the rates in general population surveys (16.1% and 6.5%, respectively); rates were much higher among sex workers (54.9% and 33.3%, respectively). Multivariate analysis revealed education to be protective, whereas exposure to female-branded cigarettes was a risk for ever smoking.

CONCLUSIONS

Chinese migrant women appear to be smoking at higher rates than nonmigrant women. Priorities for future research include representative studies in multiple cities examining reasons for uptake and stimuli to quit.

Estimation of cancer incidence and mortality attributable to smoking in China

BACKGROUND

Tobacco smoking, as a cause of cancer, is common in China. Few studies have been conducted to assess the burden of tobacco-related cancer in the Chinese population.

METHODS

We calculated the proportion of cancers attributable to tobacco smoking to estimate the burden of tobacco-related cancer. Population attributable fraction was calculated based on the assumption of total avoidance of smoking. Data on smoking prevalence were from two large-scale national surveys of representative samples of the Chinese population. Data on relative risk were derived from the meta-analyses and large-scale studies. Cancer mortality and incidence were originated from the third national death cause survey and cancer registries in China.

RESULTS

We estimated that a total of 405,112 deaths of cancer were attributable to smoking in China in 2005, including 372,264 among men (32.7% of all cancer deaths) and 32,848 among women (5.0%). A total of 495,221 cancer cases were attributable to smoking, including 454,785 among men (30.0% of all cancer cases) and 40,436 among women (3.9%). Involuntary smoking was responsible for 11,507 lung cancer deaths (11.1%) among non-smoking women.

CONCLUSION

Tobacco smoking is responsible for one-third of the total cancer deaths among men. Involuntary smoking is an important individual risk factor for lung cancer among non-smoking women. There is a need to continue and strengthen tobacco-control programs and initiatives to reduce smoking-related cancer burden in China.

Exposure to secondhand smoke and associated factors among non-smoking pregnant women with smoking husbands in Sichuan province, China

BACKGROUND

Secondhand smoke (SHS) exposure harms pregnant women and the fetus. China has the world's largest number of smokers and a high male smoking prevalence rate.

OBJECTIVE

To compare exposure to SHS among rural and urban Chinese non-smoking pregnant women with smoking husbands, and analyze factors associated with the level of SHS exposure and hair nicotine concentration.

SETTING

Sichuan province, China.

POPULATION

In all 1,181 non-smoking pregnant women with smoking husbands recruited from eight district/county Women and Children's hospitals.

METHODS

The women completed a questionnaire in April and May 2008. Based on systematic sampling, 186 pregnant women were selected for sampling the nicotine concentration in their hair. Ordinal logistic regression analysis was conducted to examine correlates with self-reported SHS exposure (total and at home); linear regression was conducted for the sub-sample of hair nicotine concentrations.

MAIN OUTCOME MEASURES

Secondhand smoking exposure rates, hair nicotine levels.

RESULTS

About 75.1% of the non-smoking pregnant women with smoking husbands reported regular SHS exposure. The major source of exposure was through their husband. In the multivariate analysis, the risk of greater SHS exposure (total and at home) and hair nicotine concentration was increased for women who were rural, had a husband with greater cigarette consumption, less knowledge about SHS, less negative attitudes about SHS, and no smoke-free home rules.

CONCLUSIONS

The high prevalence rate of SHS exposure suggests that it is important for non-smoking pregnant women, especially rural women, to establish smoke-free home rules and increase knowledge and negative attitudes towards SHS.

Physicians' role in advancing tobacco control in China

China has ratified the FCTC and is working towards implementing tobacco control measures to combat the massive health and economic consequences of tobacco use. Physicians will need to play a leading role in this fight as they have done in countries such as Australia where measures to address the tobacco epidemic are more advanced. At present in China barriers such as physicians' own smoking status and underestimation of the impact interventions with their patients can have means that their potentially positive contribution is far from realised. Physicians have a responsibility to lead in tobacco control. This should begin with their own behaviour and practices including quitting smoking if a smoker and counselling patients and families of patients to not smoke. Advocating to make hospitals and medical facilities smokefree should also be a priority for physicians. As centres where people attend to improve their health and receive treatment for illness, allowing a practice such as smoking is completely incongruous. Responsibility also rests with the facilities in which physicians work and the professional bodies who represent them, physicians should be provided with information, training and support to assist them to address their own and their patients tobacco use.

Trends in smoking and quitting in China from 1993 to 2003: National Health Service Survey data

OBJECTIVE

China has about 350 million smokers, more commonly men. Using data from National Health Service Surveys conducted in 1993, 1998 and 2003, we (i) estimated trends in smoking prevalence and cessation according to sociodemographic variables and (ii) analysed cessation rates, quitting intentions, reasons for quitting and reasons for relapsing.

METHODS

Data were collected from approximately 57 000 households and 200 000 individuals in each survey year. Household members > 15 years of age were interviewed about their smoking habits, quitting intentions and attitudes towards smoking. We present descriptive data stratified by age, sex, income level and rural versus urban residence.

FINDINGS

In China, current smoking in those > 15 years old declined 60-49% in men and 5-3.2% in women over 1993-2003. The decline was more marked in urban areas. However, heavy smoking (≥ 20 cigarettes daily) increased substantially overall and doubled in men. The average age of uptake also dropped by about 3 years. In 2003, 7.9% of smokers reported intending to quit, and 6% of people who had ever smoked reported having quit. Of former smokers, 40.6% quit because of illness, 26.9% to prevent disease and 10.9% for financial reasons.

CONCLUSION

Smoking prevalence declined in China over the study period, perhaps due to the combined effect of smoking cessation, reduced uptake in women and selective mortality among men over 40 years of age. However, heavy smoking increased. People in China rarely quit or intend to quit smoking, except at older ages. Further tobacco control efforts are urgently needed, especially in rural areas.

Two-year effects of a school-based prevention programme on adolescent cigarette smoking in Guangzhou, China: a cluster randomized trial

BACKGROUND

The prevalence of adolescent smoking has been increasing rapidly in China. Theory-based smoking prevention programmes in schools may be an effective approach in preventing smoking among Chinese adolescents.

METHODS

A school-level cluster randomized controlled trial was conducted among 7th and 8th grade students (N = 2343) in four junior high schools in southern China during 2004-06. The theory-based, multi-level intervention was compared with the standard health curriculum. Outcome measures comprised changes in students' smoking-related knowledge, attitudes and behaviour.

RESULTS

The mean knowledge scores from baseline to the 1- and 2-year follow-ups increased more in the intervention group than in the control group, whereas there was little change in attitude scores. At the 1-year follow-up (the total sample), the interventions reduced the probability of baseline experimental smokers' escalating to regular smoker [7.9 vs 18.3%; adjusted odds ratio (OR) 0.34, 95% confidence interval (CI) 0.12-0.97, P = 0.043], but did not reduce the probability of baseline non-smokers' initiating smoking (7.9 vs 10.6%; adjusted OR 0.86, 95% CI 0.54-1.38, P = 0.538). At the 2-year follow-up (only 7th grade students), similar proportions of baseline non-smokers initiated smoking in the intervention group and the control group (13.5 vs 13.1%), while a possibly lower proportion of baseline experimental smokers escalated to regular smoking in the intervention group than the control group (22.6 vs 40.0%; adjusted OR 0.43, 95% CI 0.12-1.57, P = 0.199).

CONCLUSIONS

This multi-level intervention programme had a moderate effect on inhibiting the escalation from experimental to regular smoking among Chinese adolescents, but had little effect on the initiation of smoking. The programme improved adolescents' smoking-related knowledge, but did not change their attitudes towards smoking.

Environmental tobacco use and indicators of metabolic syndrome in Chinese adults

INTRODUCTION

Exposure to environmental tobacco smoke (ETS) is a widespread source of nicotine exposure, and an estimated 540 million Chinese are exposed to ETS in mainland China. We aimed to investigate associations of ETS exposure and metabolic syndrome (MetS) as well as its individual components independent of active smoking status in Chinese adults.

METHODS

A cross-sectional data of 304 randomly selected Chinese households with fourth (elementary school) and seventh (middle school) graders in Qingdao city was used. Assessments of fat mass, metabolic biomarkers, personal history of illness, and health behaviors were conducted.

RESULTS

Proportions of current smokers were 3% in women and 60.5% in men, and more men reported exposure to ETS 5-7 days per week than women (60.8% vs. 48.1%). Exposure to ETS was significantly associated with enhanced risks of MetS (odds ratio [OR] = 2.8, p = .01), hypertriglyceridemia (OR = 2.1, p = .02), and central obesity (OR = 2.7, p < .001) and reduced levels of high-density lipoprotein cholesterol (OR = 1.9, p = .02) and elevated mean levels of fasting insulin (p < .01). These observed associations were independent of active smoking status and were successfully replicated in female never-smokers.

CONCLUSIONS

Results of our study support the hypothesis that ETS exposure is independently associated with MetS and its individual components. Further large-scale studies with longitudinal design and objective assessment of ETS exposure are needed to elucidate the underlying mechanisms and the causal effects of passive smoking on MetS. Findings of this work emphasize the importance of developing community intervention to reduce smoking, ETS, and promote healthy lifestyle.

The epidemiological profile of alcohol and other drug use in metropolitan China

PURPOSE

There is evidence that alcohol, tobacco, and other drug use may be rising in China, but epidemiological studies that examine several drugs simultaneously and the transition from initial try to current use are limited. The present study provides an epidemiological profile of drug use in contemporary metropolitan China.

METHODS

A multistage probability sampling method was used to select household-dwelling adults in Beijing and Shanghai. Standard face-to-face interviews with 5,201 participants were completed during 2002-2003.

RESULTS

An estimated 70-76% had used any type of drug: alcohol and tobacco were the most commonly used drugs (alcohol, 67%; tobacco, 39%). Regarding extra-medical use of internationally regulated drugs, sedatives and analgesics were most common and illegal drug use was rare. The majority of tobacco users used it recently (82.5%), especially young adults. Male-female differences were observed in lifetime tobacco use, but not for recent use. Concurrent use of alcohol and tobacco was very common.

CONCLUSION

Psychoactive drug use is common in metropolitan China. Public health policies and prevention initiatives may be needed to address associated problems that may increase following the country's rapid socioeconomic change.

Recovery of solanesol from tobacco as a value-added byproduct for alternative applications

Solanesol in the waste streams of a bioprocess designed for alternative applications of low-alkaloid tobacco was recovered using three different extraction methods. Compared to the conventional heat-reflux extraction (HRE) and ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) using 1:3 hexane:ethanol (v/v) as the solvent after saponification treatment of tobacco biomass was found the most effective in terms of solanesol yield, processing time, and volume of solvent consumed. Quantification of solanesol was achieved by optimizing the mobile phase at 60/40 acetonitrile-isopropanol and lowering the oven temperature to 22 degrees C using a standard reverse-phase high performance liquid chromatography (RP-HPLC). The total solanesol recovered from tobacco biomass and chloroplast accounted for 30% (w/w) of the total solanesol in the fresh leaves. Since solanesol is the precursor of metabolically active quinones such as coenzyme Q10 and vitamin K analogues, extraction of solanesol from tobacco bioprocess waste is a feasible operation and could leverage the overall profitability of biorefining tobacco for alternative, value-added uses.

Cognitive attributions for smoking among adolescents in China

To design more effective health communication messages for smoking cessation and prevention, it is important to understand people's own perceptions of the factors that influence their decisions to smoke. Studies have examined cognitive attributions for smoking in Western countries but not in the Chinese cultural context. In a study of 14,434 Chinese adolescents, exploratory factor analysis grouped 17 cognitive attributions into 8 factors: curiosity, coping, social image, social belonging, engagement, autonomy, mental enhancement, and weight control. The factors were ranked based on the participants' self-reports of importance and by the strength of their associations with smoking behavior. Among all smokers, curiosity was the most frequently-ranked attribution factor at the early stages of smoking but not for daily smoking. Coping was highly-ranked across smoking stages. Social image and social belonging were more highly-ranked at earlier stages, whereas engagement and mental enhancement were ranked more highly at later stages of smoking. More attributions were associated with smoking among males than among females. This information could be useful for the development of evidence-based anti-smoking programs in China.

Patterns of smoking and its association with psychosocial work conditions among blue-collar and service employees of hospitality venues in Shenyang, PR China

Background

To characterize the smoking patterns of hospitality employees in blue-collar and service occupations, and to examine its relations with psychosocial work conditions.

Methods

The Shenyang Hospitality Industry Employees Survey-a face-to-face cross-sectional study of representative hospitality industry employees-was conducted between March and July 2008. A total of 4,213 workers were selected using stratified random cluster sampling designs, and final analyses were performed on 2,508 blue-collar and service subjects. Multilevel-logistic regression models were used to estimate the contribution of psychosocial work conditions to smoking status.

Results

Blue-collar and service employees smoked at a rate 1.4 times that of the general population (49.4% vs. 35.8%), more particularly for females (12.9% vs. 3.08%). Strain jobs had significantly higher odds ratio of daily smoking (OR 2.09, 95%CI: 1.28-3.41) compared to the relaxed category. The passive jobs (OR 2.01, 95%CI 1.27 to 3.17), highest job demands (OR 1.72, 95%CI: 1.13-2.61), and lowest job control (OR 2.56, 95%CI: 1.57-4.16) were also associated with a significantly higher daily smoking ratio. The negative relationship between job stability and smoking behavior was slightly stronger among daily than occasional smokers. However, neither job strain nor any of its components was found to be significantly associated with occasional smoking.

Conclusions

Smoking in hospitality blue-collar and service employees is certainly a major occupational health problem in Shenyang. This evidence also suggests an association between psychosocial-work conditions and smoking status, and implies that more intervention studies where changes in work environment are carried out in combination with health promotion interventions should be performed.

Risk factors for breast cancer in postmenopausal Caucasian and Chinese-Canadian women

INTRODUCTION

Striking differences exist between countries in the incidence of breast cancer. The causes of these differences are unknown, but because incidence rates change in migrants, they are thought to be due to lifestyle rather than genetic differences. The goal of this cross-sectional study was to examine breast cancer risk factors in populations with different risks for breast cancer.

METHODS

We compared breast cancer risk factors among three groups of postmenopausal Canadian women at substantially different risk of developing breast cancer - Caucasians (N = 413), Chinese women born in the West or who migrated to the West before age 21 (N = 216), and recent Chinese migrants (N = 421). Information on risk factors and dietary acculturation were collected by telephone interviews using questionnaires, and anthropometric measurements were taken at a home visit.

RESULTS

Compared to Caucasians, recent Chinese migrants weighed on average 14 kg less, were 6 cm shorter, had menarche a year later, were more often parous, less often had a family history of breast cancer or a benign breast biopsy, a higher Chinese dietary score, and a lower Western dietary score. For most of these variables, Western born Chinese and early Chinese migrants had values intermediate between those of Caucasians and recent Chinese migrants. We estimated five-year absolute risks for breast cancer using the Gail Model and found that risk estimates in Caucasians would be reduced by only 11% if they had the risk factor profile of recent Chinese migrants for the risk factors in the Gail Model.

CONCLUSIONS

Our results suggest that in addition to the risk factors in the Gail Model, there likely are other factors that also contribute to the large difference in breast cancer risk between Canada and China.

The Chinese physicians' CardiovAscular Risk Evaluation (CARE) survey: an assessment of physicians' own cardiovascular risks

OBJECTIVE

To estimate the 10-year risk of cardiovascular disease (CVD)/coronary heart disease (CHD) in physicians using two models (the Chinese and Framingham models).

METHODS

This was a multicentre, cross-sectional survey, which recruited cardiovascular physicians from 386 medical centres in all 31 provinces and municipalities in China. Cardiovascular risk factors such as body mass index, blood pressure and cholesterol were recorded during enrolment. Control rates (%) of hypertension, hypercholesterolaemia and diabetes were defined according to guidelines. Participants aged ≥35 years completed the Framingham model and participants aged ≤59 years completed the Chinese prediction model.

RESULTS

A total of 820 (41.5%) women and 1598 (78.7%) men had ≥1 markedly raised CVD risk factors. The Chinese prediction model showed that 22 (1.2%) women and 143 (7.6%) men had a 10-year risk of ischaemic CVD ≥5%, and an above-average level of 10-year ischaemic CVD risk factors was found in 20.6% of women and in 54.6% of men. When the Framingham model was used, 268 (13.6%) women and 724 (35.7%) men had a 10-year absolute risk of CHD ≥5%. Hypertension, diabetes and hypercholesterolaemia were only controlled in 58.2%, 46.6% and 38.5% of participants, respectively. Only 30.3% of physicians with a 10-year risk of CHD ≥10% were using aspirin.

CONCLUSIONS

The results show suboptimal awareness in physicians of their own cardiovascular risks, and low use of prophylactic agents. Improvement of physicians' risk factors in will improve their ability to act as role models in the promotion of primary and secondary prevention initiatives.

Does smoking affect body weight and obesity in China?

An inverse relationship between smoking and body weight has been documented in the medical literature, but the effect of cigarette smoking on obesity remains inconclusive. In addition, the evidence is mixed on whether rising obesity rates are an unintended consequence of successful anti-smoking policies. This study re-examines these relationships using data from China, the largest consumer and manufacturer of tobacco in the world that is also experiencing a steady rise in obesity rates. We focus on the impact of the total number of cigarettes smoked per day on individuals' body mass index (BMI) and on the likelihood of being overweight and obese. Instrumental variables estimation is used to correct for the endogeneity of cigarette smoking. We find a moderate negative and significant relationship between cigarette smoking and BMI. Smoking is also negatively related to being overweight and obese, but the marginal effects are small and statistically insignificant for being obese. Quantile regression analyses reveal that the association between smoking and BMI is quite weak among subjects whose BMIs are at the high end of the distribution but are considerably stronger among subjects in the healthy weight range. Ordered probit regression analyses also confirm these findings. Our results thus reconcile an inverse average effect of smoking on body weight with the absence of any significant effect on obesity. From a policy perspective these findings suggest that, while smoking cessation may lead to moderate weight gain among subjects of healthy weight, the effects on obese subjects are modest and should not be expected to lead to a large increase in obesity prevalence rates.

Effects of Helicobacter pylori infection and smoking on gastric cancer incidence in China: a population-level analysis of trends and projections

OBJECTIVE

Although gastric cancer incidence is declining in China, trends may differ from historical patterns in developed countries. Our aim was to (1) retrospectively estimate the effects of Helicobacter pylori (H. pylori) and smoking on past gastric cancer incidence and (2) project how interventions on these two risk factors can reduce future incidence.

METHODS

We used a population-based model of intestinal-type gastric cancer to estimate gastric cancer incidence between 1985 and 2050. Disease and risk factor data in the model were from community-based epidemiological studies and national prevalence surveys.

RESULTS

Between 1985 and 2005, age-standardized gastric cancer incidence among Chinese men declined from 30.8 to 27.2 per 100,000 (12%); trends in H. pylori and smoking prevalences accounted for >30% of overall decline. If past risk factor trends continue, gastric cancer incidence will decline an additional 30% by 2050. Yet, annual cases will increase from 116,000 to 201,000 due to population growth and aging. Assuming that H. pylori prevention/treatment and tobacco control are implemented in 2010, the decline in gastric cancer incidence is projected to increase to 33% with universal H. pylori treatment for 20-year-olds, 42% for a hypothetical childhood H. pylori vaccine, and 34% for aggressive tobacco control.

CONCLUSIONS

The decline in gastric cancer incidence has been slower than in developed countries and will be offset by population growth and aging. Public health interventions should be implemented to reduce the total number of cases. Electronic supplementary material The online version of this article (doi:10.1007/s10552-009-9397-9) contains supplementary material, which is available to authorized users.

Prevalence and correlates of active and ever-smokers in metropolitan China

This study investigated the prevalence and demographic correlates of active and ever-smokers in Beijing and Shanghai. Using a multi-stage household probability sampling method, 5201 participants aged 18-70 underwent face-to-face interviews using the Composite International Diagnostic Interview. 67.1% and 55.5% of male and 7.1% and 5.5% of female respondents were ever-smokers and active smokers respectively. Quitting was less common by proportion among those no longer married or never-married, middle-aged or working adults. After adjusting for other sociodemographic factors, the oldest age-group (>54 years) showed a significantly negative association with active smoking while those no longer married had significantly positive association with active smoking, among ever-smokers. Although the high prevalence of male smoking in Beijing and Shanghai was expected, the prevalence of female smoking was significantly higher than those found in previous surveys. This pattern of more female smoking not accompanied by an obvious decrease in male smoking defies the expectation of an orderly transition of smoking patterns and may foreshadow smoking patterns in other parts of China.

Smoking among rural and urban young women in China

Methods

A survey of 11 095 urban and rural women attending high school or college, aged 14–24 years, in 6 Chinese provinces was conducted. Ever-smoking (ES), current smoking, established smoking and intention to smoke frequencies were calculated. Bivariate analyses were conducted to identify possible correlates of smoking, and those found to be significant at the p=0.1 level were included in a multivariate logistical regression model to obtain adjusted OR for correlates of ES.

Results

ES prevalence was 20.1%, with urban female students (UFS) at 22.0% and rural female students (RFS) at 19.0% (p<0.01). Established smoking prevalence was higher among UFS than RFS (2.4% vs 0.9%, p<0.01). Similarly, current smoking prevalence was higher among UFS than RFS (4.2% vs 1.9%, p<0.01). The intention to smoke prevalence was higher among UFS than RFS (3.5% vs 1.7%, p<0.01). The majority were aware that smoking was harmful to health, but were less aware of specific diseases associated with smoking. ES was associated with awareness of cigarettes made for women (OR, 1.66, 95% CI 1.49 to 1.86) and thinking that they were less harmful than other cigarettes (OR 1.54, 95% CI 1.33 to 1.79). The strongest correlate of ES was low refusal self-efficacy (OR 6.35, 95% CI 5.32 to 7.57).

Conclusions

This is the first report that having heard of women's cigarettes is a correlate of smoking among young Chinese women. ES among young Chinese women has increased in the last decade, and thus, specific prevention strategies need to be developed to prevent the tobacco epidemic from spreading among this vulnerable population.

Prior TB, smoking, and airflow obstruction: a cross-sectional analysis of the Guangzhou Biobank Cohort Study

BACKGROUND

Prior pulmonary TB has been shown to be associated with a higher risk of airflow obstruction, which is the hallmark of COPD, but whether smoking modifies this relationship is unclear. We investigated the relationships between prior TB, smoking, and airflow obstruction in a Chinese population sample.

METHODS

Participants in the Guangzhou Biobank Cohort Study underwent spirometry, chest radiography, and a structured interview on lifestyle and exposures. Prior TB was defined as the presence of radiologic evidence suggestive of inactive TB. Airflow obstruction was based on spirometric criteria.

RESULTS

The prevalence of prior TB in this sample (N = 8,066, mean age: 61.9 years) was 24.2%. After controlling for sex, age, and smoking exposure, prior TB remained independently associated with an increased risk of airflow obstruction (odds ratio = 1.37; 95% CI, 1.13-1.67). Further adjustment for exposure to passive smoking, biomass fuel, and dust did not alter the relationship. Smoking did not modify the relationship between prior TB and airflow obstruction.

CONCLUSIONS

Prior TB is an independent risk factor for airflow obstruction, which may partly explain the higher prevalence of COPD in China. Clinicians should be aware of this long-term risk in individuals with prior TB, irrespective of smoking status, particularly in patients from countries with a high TB burden.

Cigarette smoking among university students in Greece: a comparison between medical and other students

OBJECTIVES

The purpose of the study was to investigate the smoking habits of medical and other students and to explore the most important factors associated with students' smoking.

METHODS

University students were surveyed in late spring 2006 regarding their smoking status and additional health- and behavior-related characteristics.

RESULTS

A total of 1205 (269 medical and 936 nonmedical) students participated in the study. Of these 47% reported being current smokers (35% among medical students), and 30% of the smokers had already started smoking at the age of 16 years. Smokers reported a significantly higher prevalence of cough and respiratory infections and a decrease in physical fitness. The most important factor associated with smoking prevalence was friendship with smokers and maternal smoking. A better knowledge of harmful effects showed a strong association with nonsmokers. Although nonmedical students exhibited a greater possibility to be a smoker, awareness of harmful effects among medical students was not as significant as factor against smoking compared with among nonmedical students.

CONCLUSIONS

This study shows that smoking prevalence among medical and other students in Greece is extremely high. A lack of effective education against smoking in medical students was evident and this underlines the need to identify the factors to be included in planning effective antismoking programs.

Occupational risk of lung cancer among lifetime non-smoking women in Shanghai, China

OBJECTIVES

Occupational lung carcinogens have been primarily studied in men. The aim of this study was to investigate occupational lung cancer risk in a cohort of Chinese non-smoking women.

METHODS

In 1996-2000, 71 067 non-smoking women who had held a job outside the home were interviewed for the prospective Shanghai Women's Health Study in China. Exposure to lung carcinogens was assessed by matching occupation and industry titles from lifetime occupational histories with lists of jobs identified by the International Agency for Research on Cancer to have potential exposure to: (1) known (A-list); or (2) suspected (B-list) carcinogens. In addition, similar occupational titles were grouped independent of the a priori defined lists. Relative risks (RRs) were calculated using Cox proportional hazards regression.

RESULTS

During follow-up through 2005, 219 incident lung cancer cases were diagnosed. Jobs on the A-list and B-list were held by 0.8-6.7% and 2.7-9.4% of the cohort, respectively. Overall, ever holding any job on the A-list or B-list was not associated with lung cancer incidence. Indications of excess risk were found for two subgroups: painters (A-list) and rubber workers (B-list) (RR = 2.0 and 1.7, respectively, p

CONCLUSIONS

Significantly elevated lung cancer risk was associated with employment in some broad occupational categories that also included jobs with potential exposure to suspected carcinogens (B-list). The results suggest that although similar exposures to those described on the B-list may play a role in this cohort of Chinese women, carcinogenic exposure may not be restricted only to the jobs on the B-list.

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Key Words

• lung cancer
• occupational carcinogen
• a-list
• b-list
• women

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MESH Headings

• Adult
• Aged
• Carcinogens/analysis
• China/epidemiology
• Epidemiologic Methods
• Female
• Humans
• Lung Neoplasms/epidemiology
• Lung Neoplasms/etiology
• Middle Aged
• Occupational Diseases/epidemiology
• Occupational Diseases/etiology
• Occupational Exposure/adverse effects
• Occupational Exposure/analysis
• Occupations/statistics & numerical data
• Smoking

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Grants

• R01 CA070867 NCI NIH HHS
• Z01 CP010123 Intramural NIH HHS
• R01 CA70867 NCI NIH HHS

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Affiliation(s)

A Pronk Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland, USA.
J Coble
B-T Ji
X-O Shu
N Rothman
G Yang
Y-T Gao
W Zheng
W-H Chow

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Collaborators Collapse

Community smoking behavior in Changqiao, Shanghai

China has observed increasing tobacco use in the past decade. Only a few studies describing smoking behavior were reported at the community level in China. The present research aimed to obtain baseline data on tobacco use and factors that influence smoking behaviors in a local community in Shanghai, China. A total of 2100 residents in Changqiao, Shanghai, between ages 13 and 84 years were surveyed using a multistage proportional random sampling design. On the basis of that, a subsampling was conducted, and 1500 residents were randomly selected to avoid a cluster effect. There were 28.3% ever smokers (53.3% for men and 2.3% for women) and 23.5% current smokers (44.2% for men and 1.9% for women). Men ages 40 to 49 years smoked the most (more than 17 cigarettes per day on average). Age, education, and marital status were significant predictors of current smoking among men. Only 13.4% of current smokers were willing to quit. The prevalence of secondhand smoke exposure was 30.4% among nonsmokers. Smoking and secondhand smoking are serious problems in Changqiao, Shanghai. Comprehensive and intensive interventions should be implemented to motivate quitting and reduce secondhand smoke exposure.

Cross-sectional and longitudinal association of cigarette smoking with carotid atherosclerosis in Chinese adults

OBJECTIVE

To assess the cross-sectional and longitudinal association of cigarette smoking with carotid atherosclerosis in middle-aged and older Chinese adults.

METHODS

The study population consisted of 1132 residents in Beijing (748 women and 384 men) aged 35 to 64 years. Information on baseline smoking characteristics, including smoking status and pack-years was collected in 1993-1994. The cohort was resurveyed in 2002 and common carotid artery intima-media thickness (CCA-IMT) and carotid plaques were measured by B-mode ultrasound.

RESULTS

The multivariable-adjusted mean CCA-IMT at resurvey was significantly associated with smoking status at both resurvey and baseline, and was 0.72 mm for consistent current smokers, 0.71 mm for former and inconsistent smokers, and 0.70 mm for consistent never smokers at both surveys, respectively (p-trend<0.01). The multivariable-adjusted odds ratio [OR, 95% confidence interval (CI)] of having carotid plaques was 1.5 (1.0-2.1) for consistent current smokers vs consistent never smokers. In addition, there was a significant dose-response relationship between baseline smoking pack-years and multivariable-adjusted mean CCA-IMT and risk of having carotid plaques at resurvey.

CONCLUSION

Smoking is associated with carotid atherosclerosis in middle-aged and older Chinese adults both cross-sectionally and longitudinally. Smoking cessation may play a significant role in prevention and control of cardiovascular diseases in China.

Did cigarette vouchers increase female smokers in China?

BACKGROUND

From 1960 to 1980, a voucher was required to purchase cigarettes in China. The Chinese government issued vouchers to ration cigarettes, without informing its citizens that smoking was unhealthy. These vouchers were available to all adults, and allowed them to purchase specified numbers of cigarettes. As a result, a number of nonsmokers started smoking during the voucher period.

METHODS

This study included 229 female and 1165 male smokers from the China Health and Nutrition Survey 1989-2006, which provides the year in which each respondent began smoking. The percentages of male and female smokers who started smoking during the voucher period were compared using the chi-square test. Logistic regression analysis was used to study the relative risk of smoking initiation by women during the voucher period, while adjusting for confounding variables.

RESULTS

During the voucher period, 46% of female smokers and 39% of male smokers started smoking (p=0.05). Women who did not have a regular job or were less educated were more likely to start smoking. The relative risk of female smokers to have initiated smoking during the voucher period was 4.75, with a p<0.01 in the logistic regression.

CONCLUSIONS

China's policy of issuing vouchers to ration tobacco consumption had the unintended consequence of encouraging smoking, particularly among women. Issuing cigarette vouchers to every adult, combined with the inexpensive prices of cigarettes, led more women to initiate smoking. Women with low SES were particularly likely to initiate smoking.

Urbanization and the spread of diseases of affluence in China

We quantify, track and explain the distribution of overweight and of hypertension across Chinese provinces differentiated by their degree of urbanicity over the period 1991-2004. We construct an index of urbanicity from longitudinal data on community characteristics from the China Health and Nutrition Survey and compute, for the first time, a rank-based measure of inequality in disease risk factors by degree of urbanicity. Prevalence rates of overweight and hypertension almost doubled between 1991 and 2004 and these disease risk factors became less concentrated in more urbanized areas. Decomposition analysis reveals that one-half of the urbanicity-related inequality in overweight is directly attributable to community level characteristics, while for hypertension the contribution of such characteristics increased from 20% in 1991 to 62% in 2004. At the individual level, lower engagement in physical activity and farming explain more than half of the urban concentration of overweight and a rising share (28%) of the greater prevalence of hypertension in more urbanized areas. Higher incomes explain around one-tenth of the urban concentration of both overweight and hypertension, while the education advantage of urban populations has a similar sized offsetting effect.