Smoking in China: findings of the 1996 National Prevalence Survey

A model for spatial variations in life expectancy; mortality in Chinese regions in 2000

BACKGROUND

Life expectancy in China has been improving markedly but health gains have been uneven and there is inequality in survival chances between regions and in rural as against urban areas. This paper applies a statistical modelling approach to mortality data collected in conjunction with the 2000 Census to formally assess spatial mortality contrasts in China. The modelling approach provides interpretable summary parameters (e.g. the relative mortality risk in rural as against urban areas) and is more parsimonious in terms of parameters than the conventional life table model.

RESULTS

Predictive fit is assessed both globally and at the level of individual five year age groups. A proportional model (age and area effects independent) has a worse fit than one allowing age-area interactions following a bilinear form. The best fit is obtained by allowing for child and oldest age mortality rates to vary spatially.

CONCLUSION

There is evidence that age (21 age groups) and area (31 Chinese administrative divisions) are not proportional (i.e. independent) mortality risk factors. In fact, spatial contrasts are greatest at young ages. There is a pronounced rural survival disadvantage, and large differences in life expectancy between provinces.

Utility of the theory of reasoned action and theory of planned behavior for predicting Chinese adolescent smoking

One third of smokers worldwide live in China. Identifying predictors of smoking is important for prevention program development. This study explored whether the Theory of Reasoned Action (TRA) and Theory of Planned Behavior (TPB) predict adolescent smoking in China. Data were obtained from 14,434 middle and high school students (48.6% boys, 51.4% girls) in seven geographically varied cities in China. TRA and TPB were tested by multilevel mediation modeling, and compared by multilevel analyses and likelihood ratio tests. Perceived behavioral control was tested as a main effect in TPB and a moderation effect in TRA. The mediation effects of smoking intention were supported in both models (p<0.001). TPB accounted for significantly more variance than TRA (p<0.001). Perceived behavioral control significantly interacted with attitudes and social norms in TRA (p<0.001). Therefore, TRA and TPB are applicable to China to predict adolescent smoking. TPB is superior to TRA for the prediction and TRA can better predict smoking among students with lower than higher perceived behavioral control.

The effect of modifiable risk factors on pancreatic cancer mortality in populations of the Asia-Pacific region

BACKGROUND

Pancreatic cancer accounts for about 220,000 deaths each year. Known risk factors are smoking and type 2 diabetes. It remains to be seen whether these risk factors are equally important in Asia and whether other modifiable risk factors have important associations with pancreatic cancer.

METHODS

An individual participant data analysis of 30 cohort studies was carried out, involving 420,310 Asian participants (33% female) and 99,333 from Australia/New Zealand (45% female). Cox proportional hazard models, stratified by study and sex and adjusted for age, were used to quantify risk factors for death from pancreatic cancer.

RESULTS

During 3,558,733 person-years of follow-up, there were 324 deaths from pancreatic cancer (54% Asia and 33% female). Mortality rates (per 100,000 person-years) from pancreatic cancer were 10 for men and 8 for women. The following are age-adjusted hazard ratios (95% confidence interval) for death from pancreatic cancer: for current smoking, 1.61 (1.12-2.32); for diabetes, 1.76 (1.15-2.69); for a 2-cm increase in waist circumference, 1.08 (1.02-1.14). All three relationships remained significant (P < 0.05) after adjustment for other risk factors. There was no evidence of heterogeneity in the strength of these associations between either cohorts from Asia and Australia/New Zealand or between the sexes. In men, the combination of cigarette smoking and diabetes more than doubled the likelihood of pancreatic cancer (2.47; 95% confidence interval, 1.17-5.21) in both regions.

CONCLUSIONS

Smoking, obesity, and diabetes are important and are potentially modifiable risk factors for pancreatic cancer in populations of the Asia-Pacific region. Activities to prevent them can be expected to lead to a major reduction in the number of deaths from this cancer, particularly in Asia with its enormous population.

An urban-rural comparison of the prevalence of the metabolic syndrome in Eastern China

OBJECTIVE

To assess the impact of urbanisation on the prevalence of the metabolic syndrome in Chinese adults.

DESIGN

As part of a community-based cross-sectional survey conducted in 2002, a sample from rural and urban populations in East China was obtained. The metabolic syndrome is defined by the National Cholesterol Education Program Adult Treatment Panel III criteria (ATP III) and the modified ATP III, which recommended a lower waist circumference cut-off for Asians. Setting Field sites in Jiangxi and Anhui provinces and the Jing'an District of Shanghai, China.

SUBJECTS

A total of 529 non-pregnant, non-lactating urban and rural adults, aged 20-64 years without diagnosed diabetes.

RESULTS

Dwelling in urban areas was associated with higher dietary fat intake and slightly lower total energy intake, and with significantly lower occupational physical activity. Using the ATP III criteria, the prevalence of the metabolic syndrome was significantly higher for urban than rural men (12.7 vs. 1.7%, P < 0.001), and was similar between urban and rural women (10.1 vs. 9.7%, P = 0.17). These urban-rural differences were greatly enhanced when the modified ATP III criteria for the syndrome were used, for men (34.3 vs. 2.7%, P < 0.01) and women (24.1 vs. 11.4%, P = 0.07). The Asian waist circumference cut-offs (90 and 80 cm for men and women, respectively) had a better combination of sensitivity and specificity in identifying other metabolic disorders, which included high glucose, high blood pressure, high triglycerides and low high-density lipoprotein cholesterol, for this population. Conclusion For the Chinese population, urban dwelling was associated with higher prevalence of the metabolic syndrome, especially in men.

The fraction of ischaemic heart disease and stroke attributable to smoking in the WHO Western Pacific and South-East Asian regions

BACKGROUND

Tobacco will soon be the biggest cause of death worldwide, with the greatest burden being borne by low and middle-income countries where 8/10 smokers now live.

OBJECTIVE

This study aimed to quantify the direct burden of smoking for cardiovascular diseases (CVD) by calculating the population attributable fractions (PAF) for fatal ischaemic heart disease (IHD) and stroke (haemorrhagic and ischaemic) for all 38 countries in the World Health Organization Western Pacific and South East Asian regions.

DESIGN AND SUBJECTS

Sex-specific prevalence of smoking was obtained from existing data. Estimates of the hazard ratio (HR) for IHD and stroke with smoking as an independent risk factor were obtained from the approximately 600,000 adult subjects in the Asia Pacific Cohort Studies Collaboration (APCSC). HR estimates and prevalence were then used to calculate sex-specific PAF for IHD and stroke by country.

RESULTS

The prevalence of smoking in the 33 countries, for which relevant data could be obtained, ranged from 28-82% in males and from 1-65% in females. The fraction of IHD attributable to smoking ranged from 13-33% in males and from <1-28% in females. The percentage of haemorrhagic stroke attributable to smoking ranged from 4-12% in males and from <1-9% in females. Corresponding figures for ischaemic stroke were 11-27% in males and <1-22% in females.

CONCLUSIONS

Up to 30% of some cardiovascular fatalities can be attributed to smoking. This is likely an underestimate of the current burden of smoking on CVD, given that the smoking epidemic has developed further since many of the studies were conducted.

Incidence and predictors of hypertension over 8 years among Chinese men and women

OBJECTIVE

To determine the 8-year incidence of hypertension and its risk factors among Chinese adults.

METHODS

A population-based sample of 10,525 Chinese adults aged > or = 40 years and free from hypertension at baseline was followed up from 1991 to 1999-2000. Incident hypertension was defined as systolic pressure > or = 140 mmHg, diastolic pressure > or = 90 mmHg, or current use of antihypertensive medication.

RESULTS

Over a mean of 8.2 years of follow-up, 28.9% of men and 26.9% of women developed hypertension. Among men, independent predictors of incident hypertension were baseline age [relative risk (RR) per 5 years: 1.10; 95% confidence interval (CI): 1.07, 1.13], living in urban regions versus rural regions (RR: 0.74; 95% CI: 0.64, 0.85), alcohol drinking versus non-drinking (RR: 1.13; 95% CI: 1.02, 1.24), prehypertension versus normotension (RR: 1.70; 95% CI: 1.53, 1.88), heart rate (RR of third versus first tertile: 1.27; 95% CI: 1.13, 1.44), body mass index (RR of third versus first tertile: 1.28; 95% CI: 1.12, 1.46) and low versus high physical activity (RR: 1.27; 95% CI: 1.10, 1.47). Results were similar for women, with current smoking in place of alcohol drinking and opposite results for region. The population-attributable risk of modifiable risk factors was between 25 and 50%.

CONCLUSIONS

These data indicate that the incidence of hypertension is high among these Chinese adults, and suggest that 25-50% of new hypertension cases could be prevented with risk factor modification. Given the excess cardiovascular mortality associated with hypertension, these data call for urgent improvements in hypertension prevention and control programs in China.

Smoking, cessation and expenditure in low income Chinese: cross sectional survey

Background

This study was carried-out to explore smoking behaviour and smoking expenditure among low income workers in Eastern China to inform tobacco control policy.

Methods

A self-completion questionnaire was administered to 1958 urban workers, 1909 rural workers and 3248 migrant workers in Zhejiang Province, Eastern China in 2004.

Results

Overall 54% of the men and 1.8% of all women were current smokers (at least 1 cigarette per day). Smoking was least common in migrant men (51%), compared with 58% of urban workers and 64% rural inhabitants (P < 0.0001). Forty-nine percent of rural males smoke more than 10 cigarettes/day, and 22% over 20/day. The prevalence of smoking increased with age. Overall 9% of the males had successfully quit smoking. Reasons for quitting were to prevent future illness (58%), current illness (31%), family pressures (20%) and financial considerations (20%). Thirteen percent of current smokers had ever tried to quit (cessation for at least one week) while 22% intended to quit, with migrants most likely to intend to quit. Almost all (96%) were aware that smoking was harmful to health, though only 25% were aware of the dangers of passive smoking. A mean of 11% of personal monthly income is spent on smoking rising to a mean of 15.4% in rural smokers. This expenditure was found to have major opportunity costs, including in terms of healthcare access.

Conclusion

The prevalence of smoking and successful quitting suggest that smoking prevalence in low income groups in Eastern China may have peaked. Tobacco control should focus on support for quitters, on workplace/public place smoking restrictions and should develop specific programmes in rural areas. Health education messages should emphasise the opportunity costs of smoking and the dangers of passive smoking.

Association of functional catechol O-methyl transferase (COMT) Val108Met polymorphism with smoking severity and age of smoking initiation in Chinese male smokers

RATIONALE

Catechol-O-methyltransferase (COMT) is an enzyme involved in the degradation and inactivation of the neurotransmitter dopamine, which is important in mediating drug reward such as nicotine in tobacco smoke. Different COMT alleles encode enzyme whose activity varies from three- to fourfold that may affect dopamine levels and alter subjective effects of nicotine. Recent evidence also suggests that a COMT polymorphism may be especially important in determining an individual's predisposition to developing nicotine dependence.

SUBJECTS AND METHODS

We studied the COMT Val108Met polymorphism in a male population of 203 current smokers, 66 former smokers, and 102 non-smokers. The age-adjusted odds ratios were estimated by multiple logistic regression models.

RESULTS

The results showed no significant association of the COMT Val108Met with initiation, persistent smoking, or smoking cessation. However, current smokers with the Met allele had significantly higher Fagerstrom Test for Nicotine Dependence scores (7.5 +/- 2.1 vs 6.8 +/- 1.8, p = 0.018) and started smoking significantly earlier (18.4 +/- 4.9 vs 20.1 +/- 5.9 years, p = 0.036).

CONCLUSIONS

These results suggest that the COMT Val108Met polymorphism may not influence smoking status in a Chinese male population but may influence the age at which smoking started and smoking severity among smokers. However, the findings must be regarded as preliminary because of the relatively small sample size and marginal associations and should be replicated in a larger cohort.

Exploring the joint effects of silicosis and smoking on lung cancer risks

Cigarette smoking and silicosis are potential causes of lung cancer among workers exposed to silica dust, but their joint effects are unclear. We explored the possible interactions between silicosis and smoking on lung cancer risks by summarizing data from the published literature. The standardized mortality ratio or standardized incidence ratio reported in each published report was first adjusted using "smoking adjustment factors" to correct for the biased estimation of the expected numbers of lung cancer among smokers and nonsmokers when using general population rates in the indirect standardization process. The ratio of the effect of silicosis on lung cancer risk among smokers to that among nonsmoker was calculated and named the "relative silicosis effect (RSE)". The synergy index was estimated to assess the additive interaction. Metaanalyses were used to obtain the weighed means of the RSE and synergy index. Ten cohort studies were reviewed and combined to yield a weighed RSE of 0.29 (95% CI: 0.20, 0.42), indicating negative risk-ratio multiplication between smoking and silicosis on the lung cancer risk. The combined weighed synergy index was 1.00 (95% CI: 0.79, 1.26), suggesting no departure from additivity. Sensitivity analyses showed that both estimates were quite robust. The independent risk-ratio effect of silicosis on lung cancer in smokers was about 30% of that in nonsmokers, and the joint effects of smoking and silicosis on the risk of lung cancer did not deviate from additivity and hence did not support biological synergism/antagonism.

A cross-cultural and historical survey of tobacco use among various ethnic groups

This review of tobacco use in diverse historical and cultural contexts reveals a range of behaviors engaged in and perspectives held by members of respective ethnic groups, such as whether to consider tobacco as a medicine or as a problem. After its introduction to Western societies, many attributed tobacco with an array of medicinal uses, while condemning recreational use and identifying it as immoral. Tobacco has been used variously by respective ethnic groups at different times and places and these customs have flavored understandings of the relationships between tobacco and the body. Considerable ethnic variation exists not only in terms of tobacco use and abuse, but also with respect to pharmacogenetic factors that influences the consequences of tobacco exposure. There have also been different societal responses to the use of tobacco, including those related to the media, as well as to issues of treatment and prevention.

Cigarette smoking and poverty in China

Drawing on the 1998 China national health services survey data, this study estimated the poverty impact of two smoking-related expenses: excessive medical spending attributable to smoking and direct spending on cigarettes. The excessive medical spending attributable to smoking is estimated using a regression model of medical expenditure with smoking status (current smoker, former smoker, never smoker) as part of the explanatory variables, controlling for people's demographic and socioeconomic characteristics. The poverty impact is measured by the changes in the poverty head count, after smoking-related expenses are subtracted from income. We found that the excessive medical spending attributable to smoking may have caused the poverty rate to increase by 1.5% for the urban population and by 0.7% for the rural population. To a greater magnitude, the poverty headcount in urban and rural areas increased by 6.4% and 1.9%, respectively, due to the direct household spending on cigarettes. Combined, the excessive medical spending attributable to smoking and consumption spending on cigarettes are estimated to be responsible for impoverishing 30.5 million urban residents and 23.7 million rural residents in China. Smoking related expenses pushed a significant proportion of low-income families into poverty in China. Therefore, reducing the smoking rate appears to be not only a public health strategy, but also a poverty reduction strategy.

Tobacco use among youth and adults in Mainland China: the China Seven Cities Study

OBJECTIVE

The China Seven Cities Study (CSCS) monitors geographic and temporal trends in tobacco use among adolescents and adults in seven cities throughout Mainland China: Harbin, Shenyang, Wuhan, Chengdu, Kunming, Hangzhou, and Qingdao. This article presents the methodology and prevalence data from the baseline survey of the CSCS, conducted in 2002.

METHODS

Stratified random samples of middle schools, high schools, and colleges were selected within each city. Students and their parents completed self-report surveys of their tobacco use. Data were obtained from 6138 middle school students, 5848 academic high school students, 2448 vocational high school students, 2556 college students, and 25 697 parents.

RESULTS

Smoking prevalence varied across age groups, school types, genders, and cities. Past-month smoking prevalence was 9% among middle school students, 8% among academic high school students, 26% among vocational high school students, 21% among college students, and 40% among parents. Smoking prevalence was higher among males than among females, with larger gender disparities among adults than among youth. Smoking also varied across cities, with higher smoking prevalence in southwestern cities and lower prevalence in coastal cities. Intraclass correlations of students within schools are presented to inform statistical power estimates for further research in China.

CONCLUSIONS

These results provide a baseline for future longitudinal studies of smoking in these cities and identify demographic groups at risk for tobacco-related disease. Effective smoking prevention programmes for youth and smoking cessation programmes for adults are needed in China, especially in the lower-income southwestern cities and in vocational high schools throughout the country.

Changing smoking attitudes by strengthening weak antismoking beliefs - Taiwan as an example

I first explored the strength of Taiwanese high school students' beliefs regarding five antismoking messages. Findings of a nationwide survey showed that the students held these beliefs in the following order of decreasing strength: second-hand smoke damages health, smoking has long-term health consequences, smoking has short-term health consequences, cigarette marketers are manipulative, and smokers are perceived negatively. Experiment one further showed that antismoking ads featuring weakly held beliefs are more effective than those featuring strongly held beliefs. Experiment two demonstrated that antismoking campaigns need to be framed carefully; in general, it is more effective to positively frame messages about strongly held antismoking beliefs but negatively frame messages about weakly held antismoking beliefs.

Age-related smoking progression among adolescents in China

PURPOSE

This study examined the differences in smoking progression between middle and upper school students.

METHODS

The China Seven Cities Study (CSCS) is a longitudinal cohort study. The current sample consists of subjects with both baseline and one-year follow-up measures collected between October 2002 and December 2003. There were 4842 students from 62 middle schools and 5806 students from 83 upper schools. Multilevel random-coefficient modeling techniques were applied.

RESULTS

Among male never or lifetime ever smokers, middle school students were susceptible to transitioning more rapidly than upper school students (never--RR: 1.272, 95% confidence interval [CI]: .985-1.642; lifetime ever--RR: 1.497, 95% CI: .979-2.290). Among female lifetime ever smokers, middle school students were more likely to progress than upper school students (RR: 1.353, 95% CI: 1.038-1.763).

CONCLUSION

This longitudinal study is the first to explore differences in smoking progression among adolescents in China. The results revealed that over a one-year interval, there was greater progression across smoking trajectories during early adolescence (corresponding to middle school) than later adolescence (upper school). This is consistent with the neurological development hypothesis, but does not rule out alternative explanations. These findings are important to consider relative to the content and timing of prevention interventions in China where smoking rates approach 70% in adult males and are increasing rapidly in women.

High levels of carcinogenic polycyclic aromatic hydrocarbons (PAH) in 20 brands of Chinese cigarettes

Tar and nicotine levels have been made to conform to EU standards as of 1 July 2004, but data on tobacco-derived carcinogenic compounds, such as PAH, in Chinese cigarettes are lacking in the literature. Levels of tar, nicotine, carbon monoxide and PAH were measured in 20 cigarette brands purchased in China between 2003 and 2004. Higher nicotine and tar levels were found in Chinese cigarettes than in European brands just 3 months before the above deadline; carcinogenic PAH levels were about 1.5 fold higher than in European cigarettes, but analysed singly, the mean value of benzo(a)pyrene (B(a)P) and dibenzo(a,h)anthracene (DBA), the most potent carcinogenic PAH yields, were 2.4 and 4.4 fold higher, respectively. Tar levels were well correlated with carcinogenic PAH (r = 0.53, P < 0.01), thus providing an easily measurable parameter for ranking various cigarette brands in developing countries where more sophisticated techniques might not be feasible for lack of funds and expertise.

Rural-urban differentials of premature mortality burden in south-west China

BACKGROUND

Yunnan province is located in south western China and is one of the poorest provinces of the country. This study examines the premature mortality burden from common causes of deaths among an urban region, suburban region and rural region of Kunming, the capital of Yunnan.

METHODS

Years of life lost (YLL) rate per 1,000 and mortality rate per 100,000 were calculated from medical death certificates in 2003 and broken down by cause of death, age and gender among urban, suburban and rural regions. YLL was calculated without age-weighting and discounting rate. Rates were age-adjusted to the combined population of three regions. However, 3% discounting rate and a standard age-weighting function were included in the sensitivity analysis.

RESULTS

Non-communicable diseases contributed the most YLL in all three regions. The rural region had about 50% higher premature mortality burden compared to the other two regions. YLL from infectious diseases and perinatal problems was still a major problem in the rural region. Among non-communicable diseases, YLL from stroke was the highest in the urban/suburban regions; COPD followed as the second and was the highest in the rural region. Mortality burden from injuries was however higher in the rural region than the other two regions, especially for men. Self-inflicted injuries were between 2-8 times more serious among women. The use of either mortality rate or YLL gives a similar conclusion regarding the order of priority. Reanalysis with age-weighting and 3% discounting rate gave similar results.

CONCLUSION

Urban south western China has already engaged in epidemiological pattern of developed countries. The rural region is additionally burdened by diseases of poverty and injury on top of the non-communicable diseases.

Cotinine Concentration in Smokers from Different Countries: Relationship with Amount Smoked and Cigarette Type

This four-country study examined salivary cotinine as a marker for nicotine intake and addiction among smokers in relation to numbers and types of cigarettes smoked. Smoking characteristics of cigarette smokers in Brazil, China, Mexico, and Poland were identified using a standard questionnaire. Cotinine concentration was measured using a saliva sample from each participant; its relationship with numbers and types of cigarettes smoked was quantified by applying regression techniques. The main outcome measure was salivary cotinine level measured by gas chromatography. In all four countries, cotinine concentration increased linearly with cigarettes smoked up to 20 per day [11.3 ng/mL (95% confidence interval, 10.5-12.2)] and then stabilized as the number of cigarettes exceeded 20 [6.8 ng/mL per cigarette (95% confidence interval, 6.3-7.4) for up to 40 cigarettes]. On average, smokers of regular cigarettes consumed more cigarettes and had higher cotinine levels than light cigarette smokers. Cotinine concentration per cigarette smoked did not differ between regular and light cigarette smokers. Results suggest a saturation point for daily nicotine intake and minimal or no reduction in nicotine intake by smoking light cigarettes.

Stay away from tobacco: a pilot trial of a school-based adolescent smoking prevention program in Beijing, China

A quasiexperimental study was conducted to explore the efficacy of the program Stay Away from Tobacco (SAFT). Participants-from 11 classes with 381 students total in grades 7, 8, 10, and 11-were assigned by class to three groups (intervention group T with school teachers delivering the program, intervention group R with researchers delivering the program, and comparison group C). Data were collected at baseline, immediately after the intervention, and 6 months after the intervention. Self-reported smoking was the outcome measure. The 30-day smoking prevalence in group C increased from 4% at baseline to 10% at the 6-month follow-up, whereas this rate declined from 11% to 6% in group T, and from 9% to 1% in group R. For group T, the odds ratio (for 30-day smoking) and the regression coefficient (for indexed number of cigarettes smoked) assessing interactions between intervention and time were 0.20 (p < .001) and -.1605 (p < .05), respectively. The same statistics for group R were 0.09 (p < .001) and -.2406 (p < .01), respectively. The predicted smoking rate declined by 19% from baseline to 6-month follow-up in group T (11.5% vs. 9.3%), and the same rate declined by 26% in group R (11.1% vs. 8.2%). The results from this pilot trial suggest that SAFT can reduce cigarette smoking among middle and high school students through its effect on improving these students' refusal skills and changing their perceived mental and physical values from smoking. A full-scale evaluation is recommended.

Correlates of household smoking bans among Chinese Americans

No population-based data are available on the degree to which Chinese Americans have adopted smoke-free household policies and whether these policies are effective in reducing environmental tobacco smoke (ETS) exposure. The present study examines the prevalence of smoke-free home rules among Chinese Americans living in New York City, describes predictors of adopting full smoking bans in the home, and explores the association between household smoking restrictions and ETS exposure at home. In-person interviews using a comprehensive household-based survey were conducted with 2,537 adults aged 18-74 years. Interviews were conducted in Mandarin, Cantonese, and other Chinese dialects. A total of 66% of respondents reported that smoking was not allowed inside the home, 22% reported a partial ban on smoking in the home, and 12% reported no smoking ban. Among current smokers, 38% reported a full household smoking ban. Current smoking status was the strongest predictor of less restrictive household smoking policies. Knowledge of the dangers of ETS, support of smoke-free air legislation, years in the United States, gender, income, and marital status also were associated with household smoking bans. Those living with a total household smoking ban were significantly less likely to report 30-day exposure to ETS than were those living in homes with a partial ban or no ban (7% vs. 68% and 73%, respectively). In homes of smokers and nonsmokers alike, exposure to ETS remains high. Smoke-free home rules and interventions among smokers and nonsmokers to raise awareness of the dangers of ETS have the potential to significantly reduce exposure to household ETS among this immigrant population.

Tobacco use and risk of myocardial infarction in 52 countries in the INTERHEART study: a case-control study

BACKGROUND

Tobacco use is one of the major avoidable causes of cardiovascular diseases. We aimed to assess the risks associated with tobacco use (both smoking and non-smoking) and second hand tobacco smoke (SHS) worldwide.

METHODS

We did a standardised case-control study of acute myocardial infarction (AMI) with 27,089 participants in 52 countries (12,461 cases, 14,637 controls). We assessed relation between risk of AMI and current or former smoking, type of tobacco, amount smoked, effect of smokeless tobacco, and exposure to SHS. We controlled for confounders such as differences in lifestyles between smokers and non-smokers.

FINDINGS

Current smoking was associated with a greater risk of non-fatal AMI (odds ratio [OR] 2.95, 95% CI 2.77-3.14, p<0.0001) compared with never smoking; risk increased by 5.6% for every additional cigarette smoked. The OR associated with former smoking fell to 1.87 (95% CI 1.55-2.24) within 3 years of quitting. A residual excess risk remained 20 or more years after quitting (1.22, 1.09-1.37). Exclusion of individuals exposed to SHS in the never smoker reference group raised the risk in former smokers by about 10%. Smoking beedies alone (indigenous to South Asia) was associated with increased risk (2.89, 2.11-3.96) similar to that associated with cigarette smoking. Chewing tobacco alone was associated with OR 2.23 (1.41-3.52), and smokers who also chewed tobacco had the highest increase in risk (4.09, 2.98-5.61). SHS was associated with a graded increase in risk related to exposure; OR was 1.24 (1.17-1.32) in individuals who were least exposed (1-7 h per week) and 1.62 (1.45-1.81) in people who were most exposed (>21 h per week). Young male current smokers had the highest population attributable risk (58.3%; 95% CI 55.0-61.6) and older women the lowest (6.2%, 4.1-9.2). Population attributable risk for exposure to SHS for more than 1 h per week in never smokers was 15.4% (12.1-19.3).

CONCLUSION

Tobacco use is one of the most important causes of AMI globally, especially in men. All forms of tobacco use, including different types of smoking and chewing tobacco and inhalation of SHS, should be discouraged to prevent cardiovascular diseases.

Heritability of cigarette smoking and alcohol use in Chinese male twins: the Qingdao twin registry

BACKGROUND

China has the world's largest concentration of smokers (350 million) and rising alcohol consumption, yet little is known about tobacco and alcohol use aetiology. In 2000, the Chinese National Twin Registry was established to provide a genetically informative resource for investigation of health behaviour including tobacco and alcohol use.

METHODS

Using standard twin methodology, this study aimed to examine the relative contribution of genetic and environmental influences on cigarette smoking and alcohol drinking in a sample of adult Chinese twins (n = 1010 individual twins). More than half of the male twins were smokers (58%), and 32.5% reported alcohol consumption. Among male smokers, 46.4% smoked 20 or more cigarettes per day (heavy smokers) and among drinkers, 32.8% consumed one or more drinks per day. Nearly all female twins were non-smokers (99.2%) and non-drinkers (98.7%); therefore, genetic analysis was limited to male data.

RESULTS

In men, current smoking was significantly heritable [75.1%, 95% confidence interval (CI) 56.7-87.5] with no evidence for a significant contribution of shared environmental effects. Heavy smoking was more strongly influenced by genes (66.2%, 95% CI 0-88.4) than shared environment (8.7%, 95% CI 0-71.0). Similarly, current drinking was more strongly influenced by genetic effects (59.5%, 95% CI 0-87.8) than by shared environmental effects (15.3%, 95% CI 0-72.1). Amount of alcohol consumed was influenced to a similar degree by genetic (42.4%, 95% CI 0-91.8) and shared environmental factors (39.2%, 95% CI 0-82.7).

CONCLUSIONS

These results support findings from twins of Western origin on the aetiology of tobacco and alcohol use and encourage further work in Chinese twins.

The evolving implications of health and sustainability in China

Sustainability in the context of China is an immediate and massive concept. A society of 1.3 billion has economic growth of 9-10% and a dramatic rise in life expectancy. It has rapidly-accumulating material wealth, major lifestyle changes and growing inequalities. It is putting great pressure on natural resources such as water and air quality. The Chinese Government's new 5-year plan uses the term 'sustainable development' as an important social goal for the first time. Sustainability requires a global effort and Sino-European partnerships are important.

The "ultimate prize" for big tobacco: opening the Chinese cigarette market by cigarette smuggling

Novotny discusses a new study in PLoS Medicine that documents how British American Tobacco has exploited China's large cigarette smuggling problem.

Estimating the cost-effectiveness of fluticasone propionate for treating chronic obstructive pulmonary disease in the presence of missing data

OBJECTIVES

To explore the cost-effectiveness of fluticasone propionate (FP) for the treatment of chronic obstructive pulmonary disease (COPD), we estimated costs and quality-adjusted life-years (QALYs) over 3 years, based on an economic appraisal of a previously reported clinical trial (Inhaled Steroids in Obstructive Lung Disease in Europe [ISOLDE]).

METHODS

Seven hundred forty-two patients enrolled in the ISOLDE trial who received either FP or placebo had data available on health-care costs and quality of life over the period of the study. The SF-36-based utility scores for quality of life were used to calculate QALYs. A combined imputation and bootstrapping procedure was employed to handle missing data and to estimate statistical uncertainty in the estimated cumulative costs and QALYs over the study period. The imputation approach was based on propensity scoring and nesting this approach within the bootstrap ensured that multiple imputations were performed such that statistical estimates included imputation uncertainty.

RESULTS

Complete data were available on mortality within the follow-up period of the study and a nonsignificant trend toward improved survival of 0.06 (95% confidence interval [CI]-0.01 to 0.15) life-years was observed. In an analysis based on a propensity scoring approach to missing data we estimated the incremental costs of FP versus placebo to be 1021 sterling pound(95% CI 619-1338 sterling pound) with an additional effect of 0.11 QALYs (CI 0.04-0.20). Cost-effectiveness estimates for the within-trial period of 17,700 sterling pound per life-year gained (6900 sterling pound to infinity) and 9500 sterling pound per QALY gained (CI 4300-26,500 sterling pound) were generated that include uncertainty due to the imputation process. An alternative imputation approach did not materially affect these estimates.

CONCLUSIONS

Previous analyses of the ISOLDE study showed significant improvement on disease-specific health status measures and a trend toward a survival advantage for treatment with FP. This analysis shows that joint considerations of quality of life and survival result in a substantial increase in QALYs favoring treatment with FP. Based on these data, the inhaled corticosteroid FP appears cost-effective for the treatment of COPD. Confirmation or refutation of this result may be achieved once the Towards a Revolution in COPD Health (TORCH) study reports, a large randomized controlled trial powered to detect mortality changes associated with the use of FP alone, or in combination with salmeterol, which is also collecting resource use and utility data suitable for estimating cost-effectiveness.

Building capacity for tobacco control research and policy

The Fogarty International Center (FIC) initiative, "International Tobacco and Health Research Capacity Building Program" represents an important step in US government funding for global tobacco control. Low- and middle-income countries of the world face a rising threat to public health from the rapidly escalating epidemic of tobacco use. Many are now parties to the Framework Convention on Tobacco Control (FCTC) and capacity development to meet FCTC provisions. One initial grant provided through the FIC was to the Institute for Global Tobacco Control (IGTC) at the Johns Hopkins Bloomberg School of Public Health (JHSPH) to support capacity building and research programmes in China, Brazil, and Mexico. The initiative's capacity building effort focused on: (1) building the evidence base for tobacco control, (2) expanding the infrastructure of each country to deliver tobacco control, and (3) developing the next generation of leaders as well as encouraging networking throughout the country and with neighbouring countries. This paper describes the approach taken and the research foci, as well some of the main outcomes and some identified challenges posed by the effort. Individual research papers are in progress to provide more in-depth reporting of study results.

Economic burden of smoking in China, 2000

OBJECTIVE

To assess the health-related economic burden attributable to smoking in China for persons aged 35 and older.

METHODS

A prevalence-based, disease-specific approach was used to estimate the smoking attributable direct costs, indirect morbidity costs, and costs of premature deaths caused by smoking-related diseases. The primary data source was the 1998 China National Health Services Survey, which contains the smoking status, medical utilisation, and expenditures for 216,101 individuals.

RESULTS

The economic costs of smoking in 2000 amounted to $5.0 billion (measured in 2000, USD) in total and $25.43 per smoker (> or = age 35). The share of the economic costs was greater for men than women, and greater in rural areas than in urban areas. Of the $5.0 billion total costs, direct costs were $1.7 billion (34% of the total), indirect morbidity costs were $0.4 billion (8%), and indirect mortality costs were $2.9 billion (58%). The direct costs of smoking accounted for 3.1% of China's national health expenditures in 2000.

CONCLUSION

The adverse health effects of smoking constitute a huge economic burden to the Chinese society. To reduce this burden in the future, effective tobacco control programmes and sustained efforts are needed to curb the tobacco epidemic and economic losses.

Socioeconomic inequality in cigarette smoking: trends by gender, age, and socioeconomic position in South Korea, 1989-2003

OBJECTIVE

The aim of this study was to examine trends of socioeconomic differentials in smoking rates by gender, age, and socioeconomic position in South Korea.

METHODS

We used data from five Social Statistical Surveys of Korea National Statistical Office from 1989 to 2003. This study included 344,969 men and women aged 20 or over. Socioeconomic position indicators were education and occupation.

RESULTS

Age-standardized smoking rates decreased in all age groups of men and women aged 45+ between 1989 and 2003, while smoking rates among women aged 20-44 did not decrease. Education was inversely associated with smoking in both genders. Those with manual occupations had greater smoking rates than those who performed non-manual labor. Based on the relative index of inequality, unfavorable inequality trends toward low education were detected in both genders aged 20-44. However, these trends were not found at ages 45-64. For occupational class, the relative inequality in smoking measured by odds ratios remained stable among men and women between 1995 and 2003.

CONCLUSIONS

Continuous and progressive anti-smoking policy measures should be directed toward South Korean men whose smoking rates are still high. Policy efforts to reduce socioeconomic inequality in smoking, especially among young adult men and women, should be exercised. In addition, additional anti-smoking policy measures toward young women's smoking habits need to be developed in South Korea.

Patterns of cancer incidence, mortality, and prevalence across five continents: defining priorities to reduce cancer disparities in different geographic regions of the world

Efforts to reduce global cancer disparities begin with an understanding of geographic patterns in cancer incidence, mortality, and prevalence. Using the GLOBOCAN (2002) and Cancer Incidence in Five Continents databases, we describe overall cancer incidence, mortality, and prevalence, age-adjusted temporal trends, and age-specific incidence patterns in selected geographic regions of the world. For the eight most common malignancies-cancers of lung, breast, colon and rectum, stomach, prostate, liver, cervix, and esophagus-the most important risk factors, cancer prevention and control measures are briefly reviewed. In 2002, an estimated 11 million new cancer cases and 7 million cancer deaths were reported worldwide; nearly 25 million persons were living with cancer. Among the eight most common cancers, global disparities in cancer incidence, mortality, and prevalence are evident, likely due to complex interactions of nonmodifiable (ie, genetic susceptibility and aging) and modifiable risk factors (ie, tobacco, infectious agents, diet, and physical activity). Indeed, when risk factors among populations are intertwined with differences in individual behaviors, cultural beliefs and practices, socioeconomic conditions, and health care systems, global cancer disparities are inevitable. For the eight most common cancers, priorities for reducing cancer disparities are discussed.

Amblyopia prevalence and cigarette smoking by women

The relationship between cigarette smoking by young women and amblyopia in children was investigated in 13 population groups. Two searches were conducted on Medline using the following keywords for the first search: amblyopia, prevalence or incidence, and the names of specific countries. The keywords for the second search were smoking, cigarettes, women and the names of the same specific countries. Relevant articles were reviewed. A positive relationship between the rate of smoking among women and the prevalence of amblyopia in school-aged children and military recruits was found. The Pearson correlation coefficient was 0.73. The occurrence of decreased visual acuity attributed to amblyopia in disparate population groups is directly related to rates of cigarette smoking by young women.

Influences affecting adolescent smoking behavior in China

This study examined multiple influences on the use of tobacco by adolescents in China. Using the theory of triadic influences as a guide, we selected interpersonal, attitudinal/cultural, and intrapersonal constructs from baseline data to predict adolescent smoking 1 year later. We used prospective data from middle and high school students (N = 11,583) and their parents from the China Seven Cities Study, a longitudinal study that is evaluating the effects of changing economic and social factors on health behaviors including tobacco use. A multilevel regression analysis provided some support that each of the influences in the theory of triadic influences affects adolescent smoking in China. After adjusting for important confounders including age, gender, socioeconomic status, and smoking behaviors (lifetime and past 30-day) at baseline, we found significant risk factors within each of the three categories, including interpersonal influences (parental monitoring, good friend smoking, and peer smoking), attitudinal/cultural influences (school academic ranking, initial liking of smoking, and the meaning of smoking), and intrapersonal influences (susceptibility to smoking, and low self-confidence to quit smoking). Results suggest that the etiology of smoking among adolescents in China might be similar to that observed in western countries and that some of the techniques used successfully in prevention programs in those countries might be useful guides when developing prevention programs in China.

A randomized intervention of smoking for adolescents in urban Wuhan, China

BACKGROUND

Tobacco use is a significant public health problem in China. Culturally specific smoking prevention programs are needed for Chinese adolescents. This study evaluated a school-based smoking prevention curriculum with a social normative approach developed in the United States for adolescents in urban Wuhan, China.

METHODS

As a randomized trial, the intervention was implemented in 1998 with 7th grade students in seven schools with seven matched control schools. Multilevel logistic regression models were used to compare ever and recent (past-month) smoking behaviors for the control and program conditions.

RESULTS

At the 1-year follow-up, smoking had increased more rapidly in the control schools than in the program schools. The odds of baseline nonsmokers initiating smoking did not differ between the program and control groups (OR=1.08 with 95% CI=0.71, 1.64). The program prevented progression to recent smoking among boys who were baseline ever smokers. Among boys who were recent smokers at baseline, the prevention program significantly reduced risk of remaining recent smokers at follow-up (OR=0.45 with 95% CI=0.23, 0.88).

CONCLUSIONS

This social normative smoking prevention curriculum did not demonstrate a significant primary prevention effect but showed potential for secondary prevention. Culturally specific smoking prevention programs are needed for Chinese adolescents.

Tobacco smoking habits among a cross-section of rural physicians in China

OBJECTIVE

To investigate the prevalence and distribution of tobacco smoking among rural Chinese physicians.

DESIGN

A self-reporting survey adapted from previous international studies.

SETTING

A teaching hospital in Hebei Province, China.

SUBJECTS

A complete cross-section of 361 physicians working in all hospital departments.

RESULTS

The overall response rate was 79.2%, among whom 15.7% (95% confidence interval (CI) 12.0-20.4) were current smokers and 1.0% ex-smokers (95% CI 0.4-3.1). There were no female smokers when stratified by sex, although the prevalence rate among male physicians was 31.9% (95% CI 24.8-40.0). The prevalence of smoking varied widely by hospital department, ranging from zero in the obstetrics and gynaecology department, to 32.6% in the surgical unit. Smoking rates also varied by age, with physicians younger than 25 years having the lowest prevalence (6.3%). Although they only accounted for 7.1% of the entire group by number, the highest smoking prevalence was seen among physicians aged 50-54 years (31.6%).

CONCLUSIONS

Although our study suggests that smoking is an important health issue for rural Chinese physicians, the distribution of risk is not uniform. Future preventive measures will, therefore, need to consider the individual situation of physicians who smoke, particularly those in the older age groups.

Perceived smoking norms, socioenvironmental factors, personal attitudes and adolescent smoking in China: a mediation analysis with longitudinal data

PURPOSE

To gather information on inter-relationships among risk factors affecting adolescent smoking for tobacco control in China, the world's largest tobacco producer and consumer.

METHOD

Longitudinal data were collected six months apart in 2003 from 813 students in grades 7, 8, 10, and 11 from two schools in Beijing, China. Linear regression was used to assess both the direct effect from predictor variables (smoking among influential others, pro-tobacco media, and attitudes toward smoking) on cigarette use and the indirect effect mediated through the perceived smoking norms (percentage of smokers among peers).

RESULTS

Among the 803 subjects (mean age of 15.5 years, SD = 1.7; 52.1% female), 18.3% of males and 1.7% of females smoked in the past 30 days. Smoking among influential others (best friends, father, mother, male teachers, female teachers, and adults in general) and perceived positive psychological and social rewards from smoking at baseline were associated with number of cigarettes smoked at follow-up, whereas exposure to pro-tobacco media was not significantly associated with smoking. The mediated effect was greater for adult smoking (70% to 90%) than for best friend smoking (11% to 16%).

CONCLUSION

Smoking among influential others and attitudes toward smoking influence adolescent smoking both directly and indirectly. The finding of the indirect effect mediated through perceived smoking norms expands our knowledge on smoking etiology. Effective adolescent smoking intervention programs in China need to include a component targeting adult smoking to reduce perceived smoking norms.

The role of public policies in reducing smoking and deaths caused by smoking in Vietnam: Results from the Vietnam tobacco policy simulation model

A simulation model is developed for Vietnam to project smoking prevalence and associated premature mortality. The model examines independently and as a package the effects of five types of tobacco control policies: tax increases, clean air laws, mass media campaigns, advertising bans, and youth access policies. Predictions suggest that the largest reductions in smoking rates will result from implementing a comprehensive tobacco control policy package. Significant inroads may be achieved through tax increases. A media campaign along with programs to publicize and enforce clean air laws, advertising bans and youth access laws would further reduce smoking rates. Tobacco control policies have the potential to make large dents in smoking rates, which in turn could lead to many lives saved. In the absence of these measures, deaths from smoking will increase. The model also helps to identify information gaps pertinent both to modeling and policy-making.

Attitudes to smoking cessation and triggers to relapse among Chinese male smokers

Background

Smoking is related to many diseases, and the relapse to smoking after cessation in China is noticeable. We examined the attitudes of Chinese male smokers regarding smoking cessation and reasons for relapse.

Methods

We interviewed 201 male smokers in Hangzhou City, Zhejiang province, China who had tried to quit smoking at least once in order to identify reasons for quitting and situations triggering relapse.

Results

The most significant reported reasons for quitting included personal health (77.1%), the cost of cigarettes (53.7%), and family pressures to quit (29.9%). The most common factors triggering relapse were social situations (34.3%), feeling negative or down (13.4%) and times of being alone (8.4%).

Conclusion

Health and family concerns, personal factors, the influence of others and a lack of cessation resources were cited as salient factors concerning smoking cessation among male smokers in this study. Effective smoking control efforts in China will require attention to these influences if China is to curb its current smoking epidemic.

Smoking among adolescents in China: an analysis based upon the meanings of smoking theory

PURPOSE

This study utilized the Meanings of Behavior theory to examine whether meanings of smoking differ among adolescents in China who were never smokers, ever smokers, and past-30-day smokers. The Meanings of Behavior theory argues that affect takes precedence over cognitive constructs in motivating behavior This study also examined whether the associations among meanings of smoking and smoking behavior vary by age and gender

DESIGN

This study was a cross-sectional study using survey data.

SETTING

Middle and high schools in seven cities in China.

SUBJECTS

A random sample of 4724 students comprised this study.

MEASURE

A self-administered questionnaire asked about smoking behavior and incorporated the meanings of smoking scale.

RESULTS

Overall prevalence rates of ever smokers and past-30-day smokers in this sample were 24.3% and 9.0%. Smoking was much more prevalent in boys than in girls. Students in the 11th grade were more likely than those in the 7th grade to have tried smoking at some time and to have smoked within the past 30 days. Odds ratios confirmed that meanings of smoking were significantly associated with smoking behaviors.

CONCLUSIONS

Meanings of smoking are associated with smoking behavior among Chinese adolescents in that smoking may connote autonomy, control, or social relatedness. Prevention programs in China require new strategies to incorporate meanings of smoking in order to meet adolescent psychological needs for autonomy, competence, and social connections.

Twenty-year secular changes in sex specific lung cancer incidence rates in an urban Chinese population

The objective of this study was to describe trends in the incidence rates of primary lung cancer in a geographically defined Chinese population. Primary lung cancer cases (N=40,022) diagnosed between 1981 and 2000 were identified by the Tianjin Cancer Registry. Age-specific and age-adjusted incidence rates to the world standard population were examined in both males and females. Age-period-cohort (APC) model and Poisson regression were used to assess the cohort effects and incidence trends. Crude and age-adjusted incidence rates in the study period were: 66.2/100,000 and 45.2/100,000 in males; and 47.7/100,000 and 28.2/100,000 in females, respectively. The major birth cohort effect can be described as for those born before 1940, in every age group lung cancer incidence rate increased as the birth years advanced. For those born after 1940, age specific incidence rates decreased as the birth years advanced. Results from the Poisson regression analyses suggested a statistically significant increasing trend of incidence rates of lung cancer from 1981 to 1990 and changed little afterwards. Through first 10 years of the study period between 1981 and 2000, lung cancer incidence rates increased in both males and females. While the study results suggest that the age-adjusted incidence rates may have reached their peak and may even decline, as the Chinese population ages, and smoking prevalence remains high, the number of new lung cancer cases will continue to increase and overall burden of lung cancer will remain high.

The management of acute myocardial infarction in developing countries

Developing countries contribute a major share to the global burden of cardiovascular disease. Acute myocardial infarction (AMI) in particular remains one of the leading causes of death in the developing world as well as in the developed world. While the risk factors, management and outcome of AMI have been extensively studied in the developed world, limited data is available on this subject from developing countries. The current review looks at the prevalence of the classical coronary artery disease risk factors in developing countries and their association with myocardial infarction, as well as the management and outcome of AMI patients in these countries.

Baseline pulmonary function and quality of life 9 years later in a middle-aged Chinese population

STUDY OBJECTIVE

This research examined the association of baseline pulmonary function with future quality of life (QOL).

METHODS

We collected baseline pulmonary function data in 1993 and 1994, and assessed QOL using the Chinese 35-Item Quality of Life Instrument in 2002 in a cohort of 1,356 participants. We used Pearson correlation analysis, multivariate analysis of variance, and multivariate linear regression analysis to assess the relationship between pulmonary function and QOL.

RESULTS

The baseline percentage of age- and height-predicted FEV1 (FEV1%) was significantly correlated with the resurvey total QOL score (r = 0.126, p < 0.001) and with QOL scores for the general (r = 0.074, p = 0.006), physical (r = 0.085, p = 0.002), independence (r = 0.178, p < 0.001), and psychological (r = 0.064, p = 0.018) domains but not with the social and environmental domains after adjusting for age and sex. These associations were weaker for the percentage of age- and height-predicted FVC. Multiple linear regression showed that the above associations were independent of baseline and resurvey smoking status. Inclusion of respiratory symptoms in the model reduced the regression coefficients from 0.82 to 0.41 for the total QOL score and from 1.43 to 0.94 for the independence domain score, for a 10% change in FEV1%. The age- and sex-adjusted mean total QOL scores were 78, 76, 76, and 69, respectively (p < 0.001), for the groups of normal, symptomatic only, impaired pulmonary function only, and both symptomatic and impaired pulmonary function. This trend was also significant for the general, physical, independence, and psychological domain scores.

CONCLUSION

Impaired baseline pulmonary function has a significant negative impact on QOL in later life that is independent of age, sex, height, and smoking status and is largely mediated through the development of chronic respiratory symptoms.

Prevalence of Physician-Diagnosed COPD and Its Association With Smoking Among Urban and Rural Residents in Regional Mainland China

OBJECTIVES

To investigate the prevalence of physician-diagnosed COPD and to explore the relationship between the total amount of cigarettes smoked (TACS) and COPD among urban and rural adults in Nanjing, China.

DESIGN

Population-based, cross-sectional study conducted between October 2000 and March 2001.

SETTING

Administrative villages (n = 45) randomly selected from three urban districts and two rural counties of Nanjing municipality, Jiangsu province, China, with an overall population of 5.6 million.

PARTICIPANTS

All regular local residents >/= 35 years old (n = 29,319), 67.7% from urban areas and 32.3% from rural areas; 49.7% were men and 50.3% were women.

RESULTS

The response rate of potential participants was 90.1%. The overall prevalence of diagnosed COPD was 5.9%. The prevalence of COPD was significantly higher among men than in women (7.2% vs 4.7%, p = 0.000), while the difference between urban and rural participants was not statistically significant (6.7% vs 4.4%, respectively; p = 0.132). The prevalence of COPD was significantly higher among smokers than nonsmokers. After adjusting for age, gender, area of residence, fuels, heating in winter, ventilation in kitchen, passive smoking, education, occupation, average family income, alcohol drinking, cooking oil, body mass index, and physical activity, a dose-response relationship between COPD and TACS was evident in this population (odds ratio [OR], 1.60; 95% confidence interval [CI], 1.34 to 1. 92; OR, 1.39; 95% CI, 1.13 to 1.70; and OR, 1.24; 95% CI, 1.01 to 1.52 for smokers within upper, middle, and lower TACS levels compared with nonsmokers, respectively).

CONCLUSIONS

The overall prevalence of diagnosed COPD (5.9%) among Chinese adults was higher than that (2.5%) estimated by World Health Organization experts, and there was a significant gradient increase in COPD prevalence from the stratum of nonsmokers to the stratum of upper TACS.

One Hundred Years of Lung Cancer

A hundred years ago, lung cancer was a reportable disease, and it is now the commonest cause of death from cancer in both men and women in the developed world, and before long, will reach that level in the developing world as well. The disease has no particular symptoms or signs for its detection at an early stage. Most patients therefore present with advanced stage IIIB or IV disease. Screening tests began in the 1950s with annual chest x-ray films and sputum cytology but they resulted in no improvement in overall mortality compared with control subjects. The same question is now being asked of spiral low-dose computed tomographic scanning. There have been big refinements in the staging classification of lung cancer and advances in stage identification using minimally invasive technology. Postsurgical mortality has declined from the early days of the 1950s but 5-year cure rates have only barely improved. The addition of chemotherapy to radical radiotherapy, together with novel radiotherapy techniques, is gradually improving the outcome for locally advanced, inoperable non-small cell lung cancer. Chemotherapy offers modest survival improvement for patients with non-small cell lung cancer, the modern agents being better tolerated resulting in an improved quality of life. The management of small cell lung cancer, which appeared so promising at the beginning of the 1970s, has hit a plateau with very little advance in outcome over the last 15 years. The most important and cost-effective management for lung cancer is smoking cessation, but for those with the disease, novel agents and treatment approaches are urgently needed.

The impact of tobacco expenditure on household consumption patterns in rural China

Smoking is not only unhealthy, it is also expensive. Spending on tobacco could drive out other critical expenditures, including basic needs. This crowd out effect would be greatest in low-income countries, affecting not only the smoker but the rest of the family as well. The aim of this study is to examine the impact of tobacco spending on household expenditure patterns in rural China. China is a low-income country with a high prevalence of smoking, especially among men. The data, a sample of 4538 households, are from a household survey conducted in six townships in two provinces in rural China. Fractional Logit (Flogit) model is used as the estimation method. We estimate the relationship between tobacco spending and spending on 17 other categories, controlling for socio-economic and demographic characteristics of the household. The results indicate that spending on tobacco affects human capital investment (e.g. education and health), future farming productivity (e.g. farming equipment and seeds), and financial security (e.g. saving and insurance). Smokers also tend to spend more on alcohol, thus exacerbating the impact of addictive substances on spending on basic needs. Smoking expenses can harm other family members by reducing expenditures on basic needs such as foods, utilities, and durable goods consumption. Thus smoking can have important intra-family distributional impacts.

Smoking prevalence and correlates among Chinese- and Filipino-American adults: findings from the 2001 California Health Interview Survey

OBJECTIVES

We report prevalence rates and correlates of cigarette smoking among a population-based sample of Chinese- and Filipino-American adults together with rates found in other racial/ethnic groups in California.

METHODS

All analyses are based on the 2001 California Health Interview Survey.

RESULTS

The proportion of current smokers among males was lowest among Chinese Americans (14%), followed by Non-Hispanic Whites (19%), Hispanics (20%), African Americans (22%), Filipino Americans (24%), American Indians/Alaska Natives (29%), and Pacific Islanders (32%). The proportion of current smokers among females was lowest among Chinese Americans (6%), followed by Hispanics (8%), Filipino Americans (11%), Non-Hispanic Whites (17%), African Americans (20%), Pacific Islander (21%), and American Indians/Alaska Natives (32%). Smoking rates were higher among foreign-born versus U.S.-born Asian males. CHIS data show an opposite effect among Asian women: acculturation to the U.S. is associated with increased smoking prevalence rates. Multivariate analyses with Chinese and Filipino respondents showed that the likelihood of smoking varied among foreign-born versus U.S.-born men (OR 2.59 for Chinese, 1.42 for Filipino, 2.01 for all Asian men combined) and for foreign-born versus U.S.-born women (OR 0.41 for Chinese, 0.38 for Filipino, and 0.59 for all Asian women combined).

CONCLUSION

Public health intervention efforts should take into account Asian ethnic subgroup, gender, and acculturation status in targeting high-risk smoking groups.

Smoking behaviour in Taiwan, 2001

PURPOSE

To examine smoking behaviours in Taiwan and compare those behaviours to those in the USA.

METHODS

Using the National Health Interview Survey (NHIS) of Taiwan (2001), a survey of over 20 000 participants, frequencies were calculated for smoking, ex-smoking, quantity smoked, and exposure to environmental tobacco smoke (ETS). Breakdowns by age, sex, and socioeconomic status were also calculated.

RESULTS

The ratio of male to female smoking rates was 10.9 to 1 among adults (46.8%/4.3%), but 3.6 to 1 among underage teenagers (14.3%/4.0%). The proportion of underage to adult smokers was three times higher for girls than for boys. Smoking prevalence substantially increased during and after high school years, and peaked in those aged 30-39 years. Smoking rates of high school age adolescents increased more than threefold if they did not attend school or if they finished their education after high school. Low income and less educated smokers smoked at nearly twice the rate of high income and better educated smokers. The smoker/ex-smoker ratio was close to 7. Male daily smokers smoked on average 17 cigarettes/day, and females, 11. Half of the total population, especially infants and women of childbearing age, were exposed to ETS at home.

CONCLUSIONS

Taiwan has particularly high male smoking prevalence and much lower female prevalence. The low female prevalence is likely to increase if the current sex ratio of smoking by underage youth continues. The low quit rate among males, the high ETS exposure of females and young children at home, and the sharp increase in smoking rates when students leave school, are of particular concern. These observations on smoking behaviour can provide valuable insights to assist policymakers and health educators in formulating strategies and allocating resources in tobacco control.

Tobacco, oral cancer, and treatment of dependence

Tobacco dependence is recognised as a life-threatening disorder with serious oral health consequences which responds to treatment in the form of behavioural support and medication. While cigarette smoking is the most hazardous and prevalent form of tobacco use in the west, consideration also needs to be given to other forms such as bidi smoking in India, reverse smoking by several rural populations and use of snuff and chewing tobacco. The evidence that the use of tobacco is the major risk factor for oral cancer and potentially malignant lesions of the mouth is clear. Counseling to quit smoking is not applied in a systematic or frequent manner to people presenting with potentially malignant lesions of the oral cavity. This review makes recommendations for interventions by health professionals to encourage and aid cessation of tobacco use as a part of prevention of oral cancer.

Effect of environmental tobacco smoke on levels of urinary hormone markers

Our recent study showed a dose-response relationship between environmental tobacco smoke (ETS) and the risk of early pregnancy loss. Smoking is known to affect female reproductive hormones. We explored whether ETS affects reproductive hormone profiles as characterized by urinary pregnanediol-3-glucuronide (PdG) and estrone conjugate (E1C) levels. We prospectively studied 371 healthy newly married nonsmoking women in China who intended to conceive and had stopped contraception. Daily records of vaginal bleeding, active and passive cigarette smoking, and daily first-morning urine specimens were collected for up to 1 year or until a clinical pregnancy was achieved. We determined the day of ovulation for each menstrual cycle. The effects of ETS exposure on daily urinary PdG and E1C levels in a +/-10 day window around the day of ovulation were analyzed for conception and nonconception cycles, respectively. Our analysis included 344 nonconception cycles and 329 conception cycles. In nonconception cycles, cycles with ETS exposure had significantly lower urinary E1C levels (beta = -0.43, SE = 0.08, p < 0.001 in log scale) compared with the cycles without ETS exposure. There was no significant difference in urinary PdG levels in cycles having ETS exposure (beta = -0.07, SE = 0.15, p = 0.637 in log scale) compared with no ETS exposure. Among conception cycles, there were no significant differences in E1C and PdG levels between ETS exposure and nonexposure. In conclusion, ETS exposure was associated with significantly lower urinary E1C levels among nonconception cycles, suggesting that the adverse reproductive effect of ETS may act partly through its antiestrogen effects.