Smoking in China: findings of the 1996 National Prevalence Survey

Breaking and re-entering: British American Tobacco in China 1979-2000

OBJECTIVES

To analyse the strategy used by British American Tobacco (BAT) to re-enter the Chinese market from 1979 to 2000 after historically dominating the market before the 1950s.

DESIGN

Analysis of tobacco industry document files to date available only on-site at the Guildford Depository operated by BAT. An additional search of recent documents related to BAT, placed in the Minnesota Depository, was also carried out.

RESULTS

BAT has been committed to regaining its historically dominant position in China since the country reopened to foreign companies in 1979. Initially, BAT remained cautious relative to competitors in seeking joint ventures, finding market access hindered by bureaucratic complexity, restrictions on foreign investment and imports quotas, and later an advertising ban. Instead, the documents suggest BAT strongly relied on illegal imports to expand market presence of State Express 555 and other key brands. It was only when risks to contraband sales increased that the company made greater efforts to establish a legal presence in the country. Attempts to stress the long history of BAT in China and a proclaimed commitment to corporate social responsibility have been used to facilitate later negotiations.

CONCLUSION

China has remained relatively closed to transnational tobacco companies (TTCs) during its transition to a market economy, maintaining a firm grip over foreign investment and imports. Nonetheless, BAT has circumvented such restrictions through illegal imports and exploitation of inconsistencies in the local enforcement of advertising bans. Governments need to understand and address the full range of market entry tactics by TTCs in order to ensure effective tobacco control.

Family characteristics and smoking among urban and rural adolescents living in China

BACKGROUND

Adolescent smoking is a public health concern in China. Although the family is an important social influence in China, few associations among family characteristics and adolescent smoking have been examined using Chinese samples.

METHODS

Survey data on psychosocial variables and smoking were collected from a sample of 3629 7th grade adolescents (46% female; 54% male; mean age 12.7 years) in Wuhan, China. For adolescents, past 30-day smoking, family relationships, parents' negative sanctioning of smoking, parents' agreement with smoking, and parents' smoking behaviors are assessed. To account for the clustered data structure, hierarchical logistic regression analyses controlling for demographics (urbanization, age) examined the independent and multivariate effects of family characteristics for each gender.

RESULTS

Girls are less likely than boys to report smoking and are more likely to report positive family relationships, and having parents with negative attitudes toward them smoking. Positive family relationships and age were strongly associated with smoking for both genders. No significant differences exist by gender.

CONCLUSION

These findings suggest that the quality of family relationships are important for adolescent female and male smoking in China.

Respiratory symptoms in relation to residential coal burning and environmental tobacco smoke among early adolescents in Wuhan, China: a cross-sectional study

BACKGROUND

Cigarette smoking and coal burning are the primary sources of indoor air pollution in Chinese households. However, effects of these exposures on Chinese children's respiratory health are not well characterized.

METHODS

Seventh grade students (N = 5051) from 22 randomly selected schools in the greater metropolitan area of Wuhan, China, completed an in-class self-administered questionnaire on their respiratory health and home environment.

RESULTS

Coal burning for cooking and/or heating increased odds of wheezing with colds [odds ratio (OR) = 1.57, 95% confidence interval (CI): 1.07-2.29] and without colds (OR = 1.44, 95% CI: 1.05-1.97). For smoking in the home, the strongest associations were seen for cough (OR = 1.74, 95% CI: 1.17-2.60) and phlegm production (OR = 2.25, 95% CI: 1.36-3.72) without colds among children who lived with two or more smokers.

CONCLUSIONS

Chinese children living with smokers or in coal-burning homes are at increased risk for respiratory impairment. While economic development in China may decrease coal burning by providing cleaner fuels for household energy use, the increasing prevalence of cigarette smoking is a growing public health concern due to its effects on children. Adverse effects of tobacco smoke exposure were seen despite the low rates of maternal smoking (3.6%) in this population.

Education-related gender differences in health in rural China

We investigated gender differences in education-related health inequalities in rural China. Household interview data were obtained from 6 provinces in 1993 and 2001. Remarkable health inequalities existed and favored the higher educational groups; among women, the inequalities were greater and health inequalities increased from 1993 to 2001. Education serves as a more powerful mediating factor for health inequalities among women than among men in rural China.

Patterns of cigarette smoking among students from 19 colleges and universities in Jiangsu Province, China: a latent class analysis

Entrance into college may be associated with elevated risk of progression in cigarette use among Chinese students. The purpose of this study was to examine patterns and dynamics of cigarette smoking by age and grade among college students in China. Cross-sectional data from 1845 students (44% females) in 19 colleges and universities in Jiangsu Province were derived from the Chinese Youth Health Risk Behavior Survey in 2001. Data were analyzed using latent class analysis (LCA). Overall 11 mutually exclusive types (latent classes) of cigarette users were derived and their proportions estimated from four variables: lifetime smoking, past 30-day smoking, attempting to quit in the past, and intention to smoke in the future. Two types (resistant never-smokers, self-stopped resistant nonsmokers) were observed across age groups and grades for both males and females while other smoking types varied with gender, age and grade. Advanced cigarette smoking types appeared in older age groups and higher grades. The cross-sectional age and grade trend suggests substantial progression in cigarette smoking among Chinese college students, underscoring the need for prevention among these students. Results also suggest that LCA may be an effective methodology for analyzing behavioral types and their dynamics with a limited number of variables.

Cigarette smoking and exposure to environmental tobacco smoke in China: the international collaborative study of cardiovascular disease in Asia

OBJECTIVES

We estimated the prevalence of cigarette smoking and the extent of environmental tobacco smoke exposure (ETS) in the general population in China.

METHODS

A cross-sectional survey was conducted on a nationally representative sample of 15540 Chinese adults aged 35-74 years in 2000-2001. Information on cigarette smoking was obtained by trained interviewers using a standard questionnaire.

RESULTS

The prevalence of current cigarette smoking was much higher among men (60.2%) than among women (6.9%). Among nonsmokers, 12.1% of men and 51.3% of women reported exposure to ETS at home, and 26.7% of men and 26.2% of women reported exposure to ETS in their workplaces. On the basis of our findings, 147358000 Chinese men and 15895000 Chinese women aged 35-74 years were current cigarette smokers, 8658000 men and 108402000 women were exposed to ETS at home, and 19072000 men and 55372000 women were exposed to ETS in their workplaces.

CONCLUSIONS

The high prevalence of cigarette smoking and environmental tobacco smoke exposure in the Chinese population indicates an urgent need for smoking prevention and cessation efforts.

Explaining the increase in coronary heart disease mortality in Beijing between 1984 and 1999

BACKGROUND

Coronary heart disease (CHD) mortality is rising in many developing countries. We examined how much of the increase in CHD mortality in Beijing, China, between 1984 and 1999 could be attributed to changes in major cardiovascular risk factors and assessed the impact of medical and surgical treatments.

METHODS AND RESULTS

A validated, cell-based mortality model synthesized data on (1) patient numbers, (2) uptake of specific medical and surgical treatments, (3) treatment effectiveness, and (4) population trends in major cardiovascular risk factors (smoking, total cholesterol, blood pressure, obesity, and diabetes). Main data sources were the WHO MONICA and Sino-MONICA studies, the Chinese Multi-provincial Cohort Study, routine hospital statistics, and published meta-analyses. Age-adjusted CHD mortality rates increased by approximately 50% in men and 27% in women (1608 more deaths in 1999 than expected by application of 1984 rates). Most of this increase ( approximately 77%, or 1397 additional deaths) was attributable to substantial rises in total cholesterol levels (more than 1 mmol/L), plus increases in diabetes and obesity. Blood pressure decreased slightly, whereas smoking prevalence increased in men but decreased substantially in women. In 1999, medical and surgical treatments in patients together prevented or postponed approximately 642 deaths, mainly from initial treatments for acute myocardial infarction ( approximately 41%), hypertension (24%), angina (15%), secondary prevention (11%), and heart failure (10%). Multiway sensitivity analyses did not greatly influence the results.

CONCLUSIONS

Much of the dramatic CHD mortality increases in Beijing can be explained by rises in total cholesterol, reflecting an increasingly "Western" diet. Without cardiological treatments, increases would have been even greater.

Levels and correlates of knowledge about cancer risk factors among 13,293 public school students in Morelos, Mexico

BACKGROUND

Data on young people's knowledge about cancer prevention are not currently available for many populations, including Mexican young people, although cancer is the second most common cause of death among the Mexican population.

METHODS

A questionnaire was applied to 13,293 public school students aged 11-24 years in Morelos, Mexico. A knowledge-based scale was constructed from survey answers about risk factors for cancer. Data were analyzed using multivariate logistic multinomial models.

RESULTS

Knowledge levels were low: 78% of male and 74% of female students had only wrong answers to questions about risk factors for cancer. A significant dose-response gradient was observed between age and knowledge of cancer risk factors (P < 0.001), with a higher prevalence in young women at all ages (female students OR 4.6, 95% CI 3.81-5.66). Students 18 years old and older knew more than 13-year-olds (OR = 2.39; 95% CI 1.89-3.01). Sexually active students (OR 2.10; 95% CI 1.70-2.58), especially those who consistently used condoms (OR 2.84; 95% CI 1.00-8.07), knew more about cancer prevention. Tobacco smoking was the most frequently recognized cancer risk factor, and smokers also recognized this as an important cause of cancer (OR 1.37; 95% CI 1.44-2.52).

CONCLUSIONS

Our results reveal a poor level of knowledge about cancer prevention among adolescents. These data are the first step in the development of an intervention based on empirical findings that will be susceptible to evaluation.

Promotion of smoking cessation in developing countries: a framework for urgent public health interventions

The rapid rise in smoking in many developing countries will have devastating consequences; by 2030 the developing world is expected to have 7 million deaths annually from tobacco use. Many smokers express a desire to quit, but they often fail because they are addicted to tobacco. Although a number of cessation aids are now available in the developed world, their applicability and affordability in developing countries is less clear. Successful interventions will require many stakeholder groups to take action at the local, national, and international levels. We discuss smoking cessation as a means of reducing disease burden, examine factors that may limit the promotion of smoking cessation in developing countries, and propose a framework for public health action. This framework should comprise intervention with healthcare professionals, strengthening national commitment, development of a model for developing countries, changing the social acceptability of smoking, strengthening community participation, integration of smoking cessation with other healthcare services, specifying the role of healthcare professionals, development of guidelines, mobilisation of the business community, provision of financial incentives, establishing population specific smoking cessation services, increased collaboration between countries, and development of international initiatives.

Acculturation and tobacco use among Chinese Americans

OBJECTIVES

We examined the relationship between acculturation and tobacco use behaviors among Chinese Americans.

METHODS

Using a Chinese-language instrument based on validated questions from several national surveys, we conducted in-person, household-based interviews with 712 representative adults aged 18-74 years.

RESULTS

Observed smoking prevalence was 29% for men and 4% for women. Predictors of smoking cessation included being 35 years and older and having a high level of tobacco-related knowledge. Acculturation was positively associated with a history of never smoking, as was being younger than 35 years and having a high level of tobacco-related knowledge.

CONCLUSIONS

Acculturation was positively associated with never smoking among men but not with smoking cessation. However, knowledge of tobacco-related health risks was associated with both. Results indicate a need for language-specific educational interventions.

Cigarette tar yields in relation to mortality from lung cancer in the cancer prevention study II prospective cohort, 1982-8

OBJECTIVE

To assess the risk of lung cancer in smokers of medium tar filter cigarettes compared with smokers of low tar and very low tar filter cigarettes.

DESIGN

Analysis of the association between the tar rating of the brand of cigarette smoked in 1982 and mortality from lung cancer over the next six years. Multivariate proportional hazards analyses used to assess hazard ratios, with adjustment for age at enrollment, race, educational level, marital status, blue collar employment, occupational exposure to asbestos, intake of vegetables, citrus fruits, and vitamins, and, in analyses of current and former smokers, for age when they started to smoke and number of cigarettes smoked per day.

SETTING

Cancer prevention study II (CPS-II).

PARTICIPANTS

364 239 men and 576 535 women, aged > or = 30 years, who had either never smoked, were former smokers, or were currently smoking a specific brand of cigarette when they were enrolled in the cancer prevention study.

MAIN OUTCOME MEASURE

Death from primary cancer of the lung among participants who had never smoked, former smokers, smokers of very low tar (< or = 7 mg tar/cigarette) filter, low tar (8-14 mg) filter, high tar (> or = 22 mg) non-filter brands and medium tar conventional filter brands (15-21 mg).

RESULTS

Irrespective of the tar level of their current brand, all current smokers had a far greater risk of lung cancer than people who had stopped smoking or had never smoked. Compared with smokers of medium tar (15-21 mg) filter cigarettes, risk was higher among men and women who smoked high tar (> or = 22 mg) non-filter brands (hazard ratio 1.44, 95% confidence interval 1.20 to 1.73, and 1.64, 1.26 to 2.15, respectively). There was no difference in risk among men who smoked brands rated as very low tar (1.17, 0.95 to 1.45) or low tar (1.02, 0.90 to 1.16) compared with those who smoked medium tar brands. The same was seen for women (0.98, 0.80 to 1.21, and 0.95, 0.82 to 1.11, respectively).

CONCLUSION

The increase in lung cancer risk is similar in people who smoke medium tar cigarettes (15-21 mg), low tar cigarettes (8-14 mg), or very low tar cigarettes (< or = 7 mg). Men and women who smoke non-filtered cigarettes with tar ratings > or = 22 mg have an even higher risk of lung cancer.

The epidemiology of cigarette smoking in Hong Kong Chinese women

BACKGROUND

Smoking in women is a well-recognized public health problem. In many developed countries, cigarette smoking is now the single most important preventable cause of premature death in women. There are relatively few data on the epidemiology of cigarette smoking in Asian women, and this study examined the prevalence of and factors predisposing Chinese women to smoke cigarettes in Hong Kong.

METHOD

A territory-wide random telephone survey of 26,716 households in Hong Kong was conducted. A total of 1064 current smokers and 291 ex-smokers were identified in these household, and in-depth interviews of 791 current smokers, 221 ex-smokers, and 1012 controls were conducted.

RESULTS

The prevalence of cigarette smoking was 4.5% in women who were 25 years or younger, 2.6% in women aged 46-65 years, and 2.2% in women aged 65 years or older. Sixty-four percent of current smokers started when they were 19 years or younger. The main reasons for the initiation of cigarette smoking were the influence of friends, curiosity, feeling bored, or being idle. Current smokers and ex-smokers tended to have positive images of women who smoked. The following risk factors were found to be significant for cigarette smoking: less than university education, unemployment, being divorced, having a husband who smoked, and a low score on the perceived harms of cigarette smoking.

CONCLUSION

Cigarette smoking is more prevalent in younger women in Hong Kong; and psychosocial issues should be addressed to prevent future epidemics.

Smoking and liver cancer in China: case-control comparison of 36,000 liver cancer deaths vs. 17,000 cirrhosis deaths

Liver cancer and liver cirrhosis are common causes of death in China, where chronic lifelong hepatitis B infection is a major cause of both diseases. To help determine whether smoking is a cofactor for the development of liver cancer, we ascertained retrospectively the smoking habits of 36,000 adults who had died from liver cancer (cases) and 17,000 who had died from cirrhosis (controls) in 24 Chinese cities and 74 rural counties. Calculations of the smoker vs. nonsmoker risk ratios (RR) for liver cancer mortality were standardised for age and locality. Among adult men (aged 35+) there was a 36% excess risk of death from liver cancer among smokers (smoker vs. nonsmoker standardised risk ratio [RR] =1.36, with 95% confidence interval [CI] 1.29-1.43, 2p<0.00001; attributable fraction 18%). In the general male population this indicates absolute risks of death from liver cancer before age 70 of about 4% in smokers and 3% in nonsmokers (in the absence of other causes). Most liver cancer, however, occurs among the 10-12% of men with haematological evidence of chronic hepatitis B infection, so among them the corresponding risks would be about 33% in smokers and 25% in nonsmokers. The RR was approximately independent of age, was similar in urban and rural areas, was not significantly related to the age when smoking started but was significantly (p<0.001) greater for cigarette smokers than for smokers of other forms of tobacco. Among men who smoked only cigarettes, the RR was significantly (p<0.001 for trend) related to daily consumption, with a greater hazard among those who smoked 20/day (RR 1.50, 95% CI 1.39-1.62) than among those who smoked fewer (mean 10/day: RR=1.32, 95% CI 1.23-1.41). Smoking was also associated with a significant excess of liver cancer death in women (RR 1.17, 95% CI 1.06-1.29, 2p=0.003; attributable fraction 3%), but fewer women (17%) than men (62%) were smokers, and their cigarette consumption per smoker was lower. Among women who smoked only cigarettes, there was a significantly greater hazard among those who smoked at least 20/day (mean 22/day: RR=1.45, 95% CI 1.18-1.79) than among those who smoked fewer (mean 8/day: RR=1.09, 95% CI 0.94-1.25). These associations indicate that tobacco is currently responsible for about 50,000 liver cancer deaths each year in China, chiefly among men with chronic HBV infection.

Smoking as a risk factor in the health of women

It is estimated that more than 200 million women smoke worldwide. It is also estimated that if current smoking rates among men and women persist worldwide, by 2025, 9% of the world's deaths and disabilities will be related to tobacco use. Smoking is associated with an increased risk of cardiovascular disease, cancer (lung, cervix, pancreas, kidney, bladder, esophagus, pharynx), pulmonary disorders, cerebrovascular disease, and many other health risks. Smoking also adversely affects fertility and reproductive outcomes. Although a greater percentage of women smoke in developed than in developing countries, women in developing countries appear to be initiating smoking habits in increasing numbers. If current trends persist, the adverse effects of smoking on women's health clearly will continue to escalate.

Twenty-year trends of primary liver cancer incidence rates in an urban Chinese population

The objective of this study was to describe trends in the incidence rates of primary liver cancer in a geographically defined Chinese population. Primary liver cancer cases (N=13 685) were diagnosed between 1981 and 2000 and identified by the Tianjin Cancer Registry. Age-adjusted and age-specific incidence rates were examined in both males and females. Poisson regression was employed to assess the incidence rate trends. Crude and age-adjusted incidence rates in the study period were: 27.4/100 000 and 16.4/100 000 in males and 11.5/100 000 and 6.4/100 000 in females, respectively. While the results from Poisson regression analyses suggest statistically significant trends of declining incidence rates of primary liver cancer overall, trends were not consistent across age and sex groups. The decline in incidence was observed, for the most part, in the 40-69 age group, with a greater decrease in males. Our findings provide a new evidence of a downward trend in incidence rates of this disease in China for a period of 20 years. As the observed decline is relatively small and inconsistent across sex and age groups, a continued epidemiological observation on this condition is required.

Family harmony as a protective factor against adolescent tobacco and alcohol use in Wuhan, China

PURPOSE

To investigate the association between family harmony (FH) and tobacco and alcohol use (TAU) in Chinese adolescents.

METHODS

Participants completed a survey in 1998 as part of a larger study of adolescent health in Wuhan, China. Analyses were performed on subjects for whom complete data were available (n = 183; 50.8% male; mean age = 13.17 yrs, std dev = 0.59). Structural equation modeling was utilized to quantify the relationships between the FH, TAU, depression, and academic aptitude factors.

RESULTS

The conceptualized structural equation model was found to have a good fit to the data (CFI = 0.995; chi2 = 39.57 df = 38; p = 40). FH was a significant predictor of TAU (beta = -0.42, p < 0.05) and was protective. FH' was also negatively related to depression (r = -0.24, p < 0.05) and positively related to academic achievement/aptitude (r = 0.35, p < 0.05).

CONCLUSIONS

These central findings highlight the value and importance placed on FH within the Chinese culture. Future prevention programs may benefit by taking into account FH as a potential mediator of TAU in adolescents in China.

Respiratory health effects of exposure to environmental tobacco smoke

Tobacco smoke is a major component of indoor air pollution. Exposure to environmental tobacco smoke (ETS) is prevalent worldwide despite growing awareness of its adverse health effects on non-smokers. ETS contains the same toxic substances as identified in mainstream tobacco smoke. Cotinine (a metabolite of nicotine) can be measured in urine and serum of non-smokers exposed to ETS and reflects the degree of exposure. In children, exposure to ETS leads to reduced lung function, increased risk of lower respiratory tract illnesses, acute exacerbation of asthma resulting in hospitalization, increased prevalence of non-allergic bronchial hyperresponsiveness, increased risk for sudden infant death syndrome (SIDS) and possibly increased risk for asthma. Exposure to ETS is responsible for excess cost to the family's financial resources and demands on health services. In adults, exposure to ETS is associated with increased risk of lung cancer, particularly in those with high exposure and acute and chronic respiratory symptoms that improve after the cessation of exposure. Healthcare providers should advocate for non-smokers' rights in the community and support legislation to limit tobacco exposure.

Bone mass of asian adolescents in China: influence of physical activity and smoking

INTRODUCTION/PURPOSE

Research addressing the role of biology and behavior on bone development during times of peak bone acquisition in adolescence is limited. The present investigation was conducted to address the influence of body composition (lean body mass, fat mass), menarche, leisure physical activity, sports team participation, smoking, and second-hand smoke on skeletal mass of a unique sample of Asian adolescents in China.

METHODS

A total of 166 girls and 300 boys (ages 12-16 yr) participated in this study. Bone mineral density (BMD) and content (bone mineral content (BMC)) of the forearm and the os calcis were measured using dual energy x-ray absorptiometry (DXA); lean body mass (LBM) and fat mass were estimated by bioelectrical impedance analysis (BIA); grip strength was measured by isometric dynamometry. Menarche, leisure physical activity, sports team participation, and active and passive smoking were determined using questionnaire.

RESULTS

In girls, a total of 44% of the variance in forearm BMC was attributed to a model which included LBM (32%), time since menarche (10%), and age (2%); heel BMC was best predicted by LBM alone (42%), with no significant contribution by other variables. In boys, a total of 39% of the variance in forearm BMC was attributed to a model which included LBM (28%), age (5%), sports team participation (4%), height (1%), and fat mass (1%); heel BMC was best predicted by LBM (50%) and height (3%), accounting for 53% of the variance.

CONCLUSION

The findings of this study suggest that lean body mass is the primary determinant of bone mass in Chinese adolescents. Menarche is also an important contributor in girls, whereas age and sports team participation are secondary predictors of bone mass in boys.

Tai Chi as an adjunct to cardiac rehabilitation exercise training

Heart disease is a chronic condition needing lifetime secondary prevention measures to decrease morbidity and mortality, and to improve quality of life. Cardiac rehabilitation exercise training, one aspect of cardiac recovery, traditionally includes some form of aerobic fitness and, more recently, muscle strength training to improve exercise tolerance. Tai chi, widely practiced in China for centuries, is a popular form of exercise among older Chinese persons associated with enhanced well-being and health among traditional Chinese practitioners. Recent research has reported improvement in cardiorespiratory function, balance and postural stability, fall prevention, and stress reduction. A review of the literature suggests potential benefits from tai chi exercise performed as an adjunct to cardiac rehabilitation exercise training. Tai chi is cost-effective and facilitates a lifestyle of health-related behavior practices.

Determinants of salivary cotinine concentrations in Chinese male smokers

BACKGROUND

Identifying factors that affect cotinine levels in smokers may be useful for smoking cessation programs. Our aims were to characterize the distribution of salivary cotinine levels in Chinese smokers and to investigate factors that influence cotinine concentrations.

METHODS

In a cross-sectional study, 600 Chinese adult smokers answered a questionnaire on smoking habits and provided a saliva sample for cotinine analysis. Modification of the relation between number of cigarettes smoked and cotinine concentration by individual characteristics, smoking behavior, and type of tobacco was evaluated.

RESULTS

Quadratic model provided the best fit for the relation between number of cigarettes smoked in the previous 24 hours and salivary cotinine concentration. Among those smoking up to 20 cigarettes, the median cotinine concentration was higher among younger subjects, those smoking cigarettes without filter and regular rather than light cigarettes, and those inhaling frequently and deeply. Such trends were not observed among heavier smokers. The increase in cotinine per cigarette tended to be larger in those with lower median cotinine level.

CONCLUSIONS

Our findings show that smoking behavior-related factors modify the relation between number of cigarettes smoked and salivary cotinine concentration. This suggests that smokers may regulate their smoking behavior to achieve a certain optimum nicotine level.

[Prevalence and risk factors for smoking among adolescents]

OBJECTIVE

Tobacco smoking is one of the main causes of preventable disease and premature disability. The study was aimed at measuring smoking prevalence and related risk factors among adolescents.

METHODS

A population-based cross-sectional study was carried out in a representative sample of 1,187 adolescents aged 10 to 19 years living in the urban area of Pelotas, southern Brazil. All adolescents were interviewed separately using a confidential coded questionnaire. Kaplan-Meier test was performed for survival curve analysis.

RESULTS

The overall smoking prevalence rate in the sample was 12.1% (95% CI 10.3%-14%). Boys and girls had similar prevalence rates. The following were the risk factors for smoking found in the multivariate logistic regression analysis: older age (OR=28.7; 95% CI 11.5-71.4), older smoking siblings (OR=2.4; 95% CI 1.5-3.8), three or more smoking friends (OR=17.5; 95% CI 8.8-34.8) and low schooling (OR=3.5; 95% CI 1.5-8.0).

CONCLUSIONS

The prevalence of smoking among adolescents in the city of Pelotas was high. Campaigns against tobacco use should be aimed at the community and families, targeting adolescents. The government must adopt legal actions in order to prevent adolescents to have access to to smoking.

Folic acid supplements during early pregnancy and likelihood of multiple births: a population-based cohort study

BACKGROUND

Folic acid supplements are recommended for women of childbearing age to prevent neural tube defects in their offspring. Results of some studies, however, suggest an increase in multiple births associated with use of vitamin supplements that contain folic acid during pregnancy. Our aim was to assess this association.

METHODS

We used data from a population-based cohort study from which we assessed the occurrence of multiple births in women (n=242015) who had participated in a campaign to prevent neural tube defects with folic acid supplements (400 microg per day) in China. Folic acid use was ascertained before pregnancy outcome was known. We studied the relation between multiple births and any use of folic acid pills before or during early pregnancy; additionally, we investigated mechanisms by which folic acid could potentially affect the occurrence of multiple births by examining pill-taking at three time periods: before ovulation, around the time of fertilisation, and after conception.

FINDINGS

1496 (0.62%) multiple births occurred in a cohort of 242015 women who had registered with the study between October, 1993, and September, 1995, and who had a pregnancy not affected by a birth defect; the rate of multiple births in women who did and did not take folic acid before or during early pregnancy was 0.59% and 0.65%, respectively (rate ratio 0.91; 95% CI 0.82-1.00).

INTERPRETATION

Our findings suggest that consumption of folic acid supplements during pregnancy is not associated with an increased occurrence of multiple births.

Epidemiology of lung cancer

In the United States, lung cancer remains the leading cause of cancer death in both men and women even though an extensive list of risk factors has been well-characterized. Far and away the most important cause of lung cancer is exposure to tobacco smoke through active or passive smoking. The reductions in smoking prevalence in men that occurred in the late 1960s through the 1980s will continue to drive the lung cancer mortality rates downward in men during the first portion of this century. This favorable trend will not persist unless further reductions in smoking prevalence are achieved.

Asbestos related diseases from environmental exposure to crocidolite in Da-yao, China. I. Review of exposure and epidemiological data

BACKGROUND

Scattered patches of crocidolite, one form of asbestos, were found in the surface soil in the rural county of Da-yao in southwestern China. In 1983, researchers from the West China University of Medical Sciences (WCUMS) discovered that residents of two villages in Da-yao had hyperendemic pleural plaques and excessive numbers of pleural mesotheliomas.

AIMS

To review and summarise epidemiological studies, along with other relevant data, and to discuss the potential contribution to environmental risk assessment.

METHODS

This report is based on a review of several clinical/epidemiological studies conducted by WCUMS researchers since 1984, which included one cross sectional medical examination survey, one clinical/pathological analysis of 46 cases of mesothelioma, and three retrospective cohort mortality studies. Additional information acquired from reviewing original data first hand during a personal visit along with an interview of medical specialists from Da-yao County Hospital was also incorporated.

RESULTS

The prevalence of pleural plaque was 20% among peasants in Da-yao over 40 years of age in the cross sectional survey. The average number of mesothelioma cases was 6.6 per year in the 1984-95 period and 22 per year in the 1996-99 period, in a population of 68 000. For those mesothelioma cases that were histology confirmed, there were 3.8 cases/year in the first period and 9 cases/year in the second. Of the 2175 peasants in this survey, 16 had asbestosis. Lung cancer deaths were significantly increased in all three cohort studies. The annual mortality rate for mesothelioma was 85 per million, 178 per million, and 365 per million for the three cohort studies, respectively. The higher exposed peasants had a fivefold increased mesothelioma mortality compared to their lower exposed counterparts. There were no cases of mesothelioma in the comparison groups where no crocidolite was known to exist in the environment. In the third cohort study, almost one of five cancer deaths (22%) was from mesothelioma. The ratio of lung cancer to mesothelioma deaths was low for all three studies (1.3, 3.0, and 1.2, respectively).

CONCLUSIONS

The observation of numerous mesothelioma cases at Da-yao was a unique finding, due mainly to their lifetime exposure to crocidolite asbestos. The finding of cases dying at a younger age and the relatively high ratio of mesothelioma cases to lung cancer could also be another unique result of lifetime environmental exposure to crocidolite asbestos. Although the commercial use of crocidolite has been officially banned since 1984, the incidence of mesothelioma has continued to show a steady increase, particularly among peasants. Since the latency of mesothelioma is approximately 30-40 years, the ban had little effect in the 1990s. The increased awareness and changes in diagnosis over time may also contribute to the increase. Furthermore, exposure to asbestos stoves and walls continued. The government implemented reduction of these exposures. However, from a public health standpoint, the most important issue is the complete avoidance of further exposure to asbestos.

Reducing the global burden of cardiovascular disease: the role of risk factors

During the last century, cardiovascular disease (CVD) has burgeoned from a relatively minor disease worldwide to a leading cause of morbidity and mortality. By 2020 it is projected that CVD will surpass infectious disease as the worlds leading cause of death and disability. Some of this increase in the relative importance of CVD is due to improved public health measures and medical care leading to longer life spans and reduced mortality from other causes. However, a substantial portion of the increasing global impact of CVD is attributable to economic, social, and cultural changes that have led to increases in risk factors for CVD. These changes are most pronounced in the countries comprising the developing world. Because the majority of the worlds population lives in the developing world, the increasing rate of CVD in these countries is the driving force behind the continuing dramatic worldwide increase in CVD. In order to blunt the impact of the global explosion in CVD, it will be crucial to attempt to understand and reduce the global increase in CVD risk factors. In this review, the authors describe the changes responsible for the global epidemic of CVD, with particular attention to the contributions of established risk factors and their impact on the growth of CVD among the worlds various economic sectors. The authors outline the major challenges facing countries in different economic sectors, and discuss ways to address these challenges with the goal of reducing the global burden of CVD.

Evolution of particulate regulation in China--prospects and challenges of exposure-based control

China's urban and rural populations face very serious health risks from combustion particles. Major sources of exposure to inhalable particulates include the burning solid fuels (biomass and coal) for household cooking and heating, coal-fired industrial and residential boilers, tobacco smoking, and diesel motor vehicles. China began to address particulate pollution problems over 25 years ago and has implemented a series of progressively more aggressive policies. This paper reviews the successes and limitations of past and existing policies for particulate controls, as well as the effects of China's economic reforms and energy policies on particulate exposure and pollution management. We examine the challenge of emissions reporting, required as part of both China's pollution levy system and emerging system for "total emissions control." Finally, we discuss practical steps toward exposure-based regulation of particulates, which would take advantage of the high cost-effectiveness for lifesaving of controlling particulate exposure from household and neighborhood sources relative to that of controlling exposure from industrial sources.

DNA repair gene XRCC1 and XPD polymorphisms and risk of lung cancer in a Chinese population

X-ray repair cross-complementing group 1 (XRCC1) and xeroderma pigmentosum group D (XPD) are mainly involved in base excision repair (BER) and nucleotide excision repair (NER) of DNA repair pathways, respectively. Polymorphisms of DNA repair gene XRCC1 and XPD has recently been identified, and there is a growing body of evidence that these polymorphisms may have some phenotypic significance. To investigate the role of XRCC1 polymorphisms (codon 194 and codon 399) and XPD polymorphism (codon 751) in lung cancer, a population-based case-control study of 109 lung cancer patients and 109 healthy control subjects (individually matched on age and gender) in a Chinese population was conducted. XRCC1 and XPD genotypes were identified using PCR-restriction fragments length polymorphism technique. Conditional logistic regression analysis revealed that XRCC1 codon 194Trp/Trp genotype was associated with a borderline increased risk of lung cancer [adjusted odd ratio (OR) = 3.06; confidence interval (CI) 0.94-9.92]. The XPD 751 Lys allele (combined Lys/Lys and Lys/Gln genotypes) was associated with a significantly increased risk of lung cancer (OR = 3.19; CI 1.01-10.07). The risk of lung cancer increased more than additive interaction (adjusted OR = 8.77; CI 1.47-52.31) for the individuals with both putative high-risk genotypes of XRCC1 194 Trp/Trp and XPD 751 Lys allele. Our results suggested that the genotypes of XRCC1 194Trp/Trp and XPD 751 Lys allele might be the risk genotypes for lung cancer in Chinese population.

Smoking behaviours and attitudes among male restaurant workers in Boston's Chinatown: a pilot study

OBJECTIVE

Asian American immigrants experience high rates of cigarette smoking. A community based survey was conducted to understand the smoking behaviours, knowledge, and attitudes of restaurant workers in Boston's Chinatown.

DESIGN

Cross sectional survey in Chinese of a convenience sample of 54 restaurant workers recruited through extensive outreach activities.

RESULTS

All 54 of the workers were male immigrants. 45 (83.3%) reported smoking cigarettes regularly, and the remaining nine were former smokers. 36 of the smokers (80.0%) started smoking before entering the USA. The workers were aware that cigarettes are addictive (98.1%), cause lung cancer (79.6%), and lead to heart disease (64.8%). However, a substantial number reported that smoking was relaxing (75.9%) and enhanced concentration (66.7%). Nearly half believed low tar and low nicotine cigarettes to be safer than standard brands. The vast majority of workers believed that smoking was not socially acceptable for women. Smokers reported they received information on quitting most commonly from friends (60%), newspapers (53.5%), and television (44.4%). The restaurant workers most often saw advertising against smoking in Chinese newspapers (63%).

CONCLUSION

Despite high rates of smoking, Chinese American restaurant workers were generally aware of the health risks and were interested in quitting. Community based research can set the stage for targeted public health efforts to reduce smoking in immigrant communities.

Peer influences and access to cigarettes as correlates of adolescent smoking: a cross-cultural comparison of Wuhan, China, and California

BACKGROUND

Few studies have assessed the effects of access to cigarettes and peer influences on adolescent smoking in non-Western countries. Using samples characterized by two distinct cultural, social, and economic systems, this study evaluated the associations of friends' smoking and perceived access to cigarettes with adolescent smoking behavior in California and Wuhan, China.

METHODS

Survey data were obtained from 5870 eighth-grade students in the Independent Evaluation of the California Tobacco Control Program and 6992 seventh- to ninth-grade students in the Wuhan Smoking Prevention Trial. Odds ratios for lifetime and 30-day smoking, according to friends' smoking and perceived access to cigarettes, were calculated for boys and girls in both samples and compared.

RESULTS

California students were more likely than Wuhan students to have friends who smoked and to perceive easy access to cigarettes. The smoking prevalence was lower in Wuhan than in California, mainly due to the low smoking prevalence among Wuhan girls. Friends' smoking was strongly associated with smoking in both samples, and the strength of this association did not differ between the two cultures. Access to cigarettes was associated with a higher risk of lifetime smoking in both cultures and a higher risk of past 30-day smoking in California only.

CONCLUSIONS

Despite divergent tobacco control policy enforcement, social structures, and cultural contexts, similarities exist between Wuhan and California. The findings suggest support for adapting a social-influences-based smoking prevention program developed in the United States to the culturally specific needs of youth in Wuhan, China.

Commuting, leisure-time physical activity, and cardiovascular risk factors in China

PURPOSE

The relationship between both commuting and leisure-time physical activity and selected cardiovascular risk factors was analyzed.

METHODS

A cross-sectional survey was carried out in 1996 in urban Tianjin, China. A total of 2002 male and 1974 female subjects aged 15-69 yr completed the survey. Commuting, leisure-time physical activity, body mass index, blood pressure, and cigarette smoking were determined.

RESULTS

Doing more than 60 min of commuting physical activity or combined commuting and leisure-time physical activity was related to the highest mean blood pressure and the highest prevalence of hypertension among both genders compared with going to and from work by bus; 31-60 min commuting only or commuting plus leisure-time physical activity was associated with the lowest mean blood pressure in women and the lowest prevalence of hypertension in both genders. Daily time on commuting or leisure-time physical activity was inversely related to mean body mass index and prevalence of overweight among men and prevalence of smoking among both genders.

CONCLUSION

The present study suggests that commuting and leisure-time physical activity were favorably associated with cardiovascular risk factors in this Chinese population, except that more than 60 min of physical activity was associated with high blood pressure.

Slower metabolism and reduced intake of nicotine from cigarette smoking in Chinese-Americans

BACKGROUND

Lung cancer rates are lower in Asians and Latinos than in whites. Ethnic differences in nicotine metabolism might explain, in part, ethnic differences in cigarette consumption and/or nicotine intake per cigarette and resultant tobacco-related cancer risk. We compared the rate of nicotine metabolism and the intake of nicotine per cigarette smoked among smokers of different ethnicities.

METHODS

Healthy volunteer smokers, including 37 Chinese-Americans, 40 Latinos, and 54 whites, received simultaneous infusions of deuterium-labeled nicotine and cotinine, a metabolite of nicotine. From blood and urine measurements, the disposition kinetics and daily intake of nicotine from smoking were determined. All statistical tests were two-sided.

RESULTS

Total and nonrenal clearance of nicotine and cotinine and metabolic clearance of nicotine via the cotinine pathway were similar in Latinos and whites and statistically significantly lower in Chinese-Americans. Intake of nicotine per cigarette by Chinese-Americans (0.73 mg; 95% confidence interval [CI] = 0.53 to 0.94 mg) was statistically significantly lower than that by Latinos (1.05 mg; 95% CI = 0.85 to 1.25 mg) or whites (1.10 mg; 95% CI = 0.91 to 1.30 mg; P =.039). Among all of the participants, there was a statistically significant positive correlation between nicotine clearance and daily intake of nicotine from cigarette smoking and between nicotine clearance and nicotine intake per cigarette (r =.41 and r =.39, respectively) (P<.001 for both).

CONCLUSIONS

The lower nicotine (and, therefore, tobacco smoke) intake per cigarette and the fewer cigarettes smoked per day, which may result, in part, from slower clearance of nicotine, may explain lower lung cancer rates in Chinese-Americans. Lower lung cancer rates among Latinos compared with whites, given their similar nicotine intake per cigarette, are probably due to smoking fewer cigarettes. The results with Chinese-Americans may have implications for dosing with nicotine medications to aid smoking cessation in Chinese- American smokers and perhaps in other Asian smokers.

Global burden of cardiovascular diseases: Part II: variations in cardiovascular disease by specific ethnic groups and geographic regions and prevention strategies

This two-part article provides an overview of the global burden of atherothrombotic cardiovascular disease. Part I initially discusses the epidemiological transition which has resulted in a decrease in deaths in childhood due to infections, with a concomitant increase in cardiovascular and other chronic diseases; and then provides estimates of the burden of cardiovascular (CV) diseases with specific focus on the developing countries. Next, we summarize key information on risk factors for cardiovascular disease (CVD) and indicate that their importance may have been underestimated. Then, we describe overarching factors influencing variations in CVD by ethnicity and region and the influence of urbanization. Part II of this article describes the burden of CV disease by specific region or ethnic group, the risk factors of importance, and possible strategies for prevention.

Survey of smoking knowledge, attitudes and practice in school children in Honduras

OBJECTIVE

The aim of this study was to survey Honduran pre-adolescent knowledge, perceptions and experience regarding smoking.

METHODS

A 12-item survey was administered in the classroom to fifth and sixth grade students. The main outcome measures were a description of demographic factors, personal smoking experience, knowledge of health risks, attitudes about tobacco use and perceived sources of information.

RESULTS

A total of 225 students were surveyed. The majority were aware that smoking is bad for health, and most reported never having smoked. Most viewed smoking as ugly. Friends and family were selected as the major source of information.

CONCLUSIONS

School children in this area of Honduras are aware of the health risks of smoking and view smoking as unattractive.

Smoking among youths in China

OBJECTIVES

To inform a prevention strategy, this study determined the prevalence of and attitudes toward smoking among Chinese secondary school students.

METHODS

Self-completion questionnaires were administered to 13- to 18-year-olds attending school in Zhejiang Province, eastern China.

RESULTS

Of the 6674 respondents, 15.9% (25.7% of the boys, 5.4% of the girls) were ever smokers. Only 0.3% were regular smokers. Of the ever smokers, 41.9% had smoked before 10 years of age and 7.9% before 5 years of age. Parental smoking was the strongest predictor of smoking.

CONCLUSIONS

The very low prevalence of regular smoking found in this age group suggests that prevention programs in school may be beneficial. Parents should be encouraged to adopt more responsible attitudes toward smoking in the home.

Adolescent smoking in Wuhan, China: baseline data from the Wuhan Smoking Prevention Trial

BACKGROUND

This study reports the prevalence of adolescent smoking in the urban and rural areas of Wuhan, China, the capital of Hubei Province, on the Yangtze River in central China.

METHODS

Smoking behavior was examined by age, gender, and urbanicity as part of the Wuhan Smoking Prevention Trial. Subjects included 6994 seventh- to ninth-grade students attending 22 randomly selected schools in urban and rural districts. Outcome measures included lifetime smoking, past-30-day smoking, established smoking (>100 cigarettes in lifetime), and susceptibility to smoking (absence of a firm commitment not to smoke).

RESULTS

Lifetime smoking prevalence was 47% among boys and 18% among girls. Past-30-day smoking prevalence was 16% among boys and 4% among girls. Established smoking prevalence was 2% among boys and 0% among girls. The prevalence of susceptibility to smoking was 31% among boys and 10% among girls. Smoking increased significantly with age (p<.0005). Susceptibility was more prevalent in rural areas than in urban areas (p<.05), but there were no urban-rural differences in lifetime, past 30-day smoking, or established smoking. Trend analyses revealed that smoking increased with age more rapidly among boys than among girls (p<.05). Smoking was more prevalent among rural boys than among urban boys, but it was more prevalent among urban girls than among rural girls (p<.05).

CONCLUSIONS

Adolescent smoking is a significant public health problem in China. Boys are at particularly high risk, as are girls living in urban areas. Effective smoking prevention programs for adolescents, as well as restrictions on tobacco industry marketing and youth access to tobacco, are needed to prevent tobacco-related morbidity and mortality in China.

'Smoke like a man, die like a man'?: a review of the relationship between gender, sex and lung cancer

Lung cancer is one of the most important 'avoidable' causes of death world-wide. It is also one in which differences in relation to sex and gender are especially significant. Increasing lung cancer deaths amongst women alongside stable or decreasing deaths amongst men in many countries have substantially altered the male:female ratio in this disease and produced a need to understand differences between men and women in lung cancer risk, and how they relate to sex and gender. This paper reviews research on differences between men and women in lung cancer incidence, mortality and survival, focusing on material which adds to our understanding of the complex differences between each group. This review suggests that the risk of lung cancer may be different for men and women in response to a complex interaction between biological factors such as hormonal difference and gendered factors such as smoking behaviour. In particular women's apparently greater relative risk of lung cancer and the differences between men and women in the risk of specific histological types of lung cancer need to be understood from a perspective in which both biological influences and gender influences are drawn out.

Weight gain and its predictors in Chinese adults

OBJECTIVE

To describe 8 y weight change in Chinese adults and to determine the baseline characteristics of those who gained weight.

DESIGN

A population-based cohort study of weight change and its predictors from 1989 to 1997.

PARTICIPANTS

A cohort of 2488 adults aged 20-45 in 1989 drawn from seven provinces in China using multistage, random cluster sampling.

MEASUREMENTS

Weight change over 8 y was the outcome variable. The key exposures were baseline energy intake, physical activity at work, alcohol consumption and smoking status. Baseline weight, weight status, height, age, residence, income and educational attainment were control variables.

RESULTS

Overweight (body mass index, BMI>or=25 kg/m(2)) doubled in females (10.4-20.8%) and almost tripled in males (5.0-14.1%). Low physical activity was a strong predictor of weight gain. Compared to those whose weight remained stable (+/-2 kg/8 y), males and females who experienced large weight gain (>5 kg/8 y) were 3 and 1.8 times more likely to engage in light rather than heavy work-related physical activity.

CONCLUSION

The prevalence of overweight increased dramatically in this cohort. Light work-related physical activity was the strongest predictor of this weight gain.

Smoking cessation in China: findings from the 1996 national prevalence survey

OBJECTIVES

To describe patterns of smoking and smoking cessation in China within the context of the stages of change model, using data from the 1996 national prevalence survey.

DESIGN

A cross sectional survey was carried out using the 145 preselected disease surveillance points, which provide a representative sample for the entire country. A standardised questionnaire on smoking was interviewer administered.

SETTING

The country of China.

SUBJECTS

122,220 people aged 15-69 years. MAINTENANCE MEASURES: Smoking cessation patterns, as defined by smoking status (current or former) and stage of change (precontemplation, contemplation, and action).

RESULTS

The sample included 45,995 ever smokers of whom 4336 had quit. About 72% of current smokers reported not intending to give up their smoking behaviour, and about 16% of current smokers said they intended to do so, but have not taken any action. Of all ever smokers, the percentage of former smokers was 9.5%, and 12% of current smokers had quit at least once, but relapsed by the time of the survey. The patterns were similar in men and women with regard to the stated intent to quit. Among males, the percentage of former smokers increased with age but the percentage intending to quit was constant at about 15% across age strata. The most common reason for quitting was illness. Participants with a university education were more likely to have made an attempt to quit.

CONCLUSIONS

The percentage of smokers contemplating quitting was low in China in 1996. The study shows that smokers in China must be mobilised to contemplate quitting and then to take action.

Hazard of smoking initiation by age among adolescents in Wuhan, China

BACKGROUND

Knowledge about age of smoking initiation among adolescents in China is helpful for exploring cultural differences in adolescent smoking behavior and informative for global tobacco control. However, little has been documented on this issue.

METHOD

Adolescents (6,473) attending grades 7, 8, and 9 completed the baseline survey of a longitudinal, randomized smoking prevention trial. Data were collected in classrooms with a paper-and-pencil questionnaire. A survival model was used in the statistical analysis.

RESULTS

The hazard of smoking initiation for boys showed a pattern previously observed in the United States: very low (<2%) before 7 years of age, increasing rapidly after age 10, and peaking at 14-15 years of age. The hazard for girls was below or around 1% until 12 years of age before it increased. The hazard levels were similar for adolescents both in urban and in rural areas, but higher for those in grade 7 than in grades 8 and 9.

CONCLUSIONS

Chinese boys in Wuhan, China, experienced a hazard pattern of smoking initiation by age similar to those observed in the United States, while Chinese girls there experienced a rather low risk of smoking initiation. The hazard pattern suggests that the best time for smoking prevention is between 10 and 15 years of age. Adolescents in lower grades are at higher risk of early smoking initiation, suggesting a potential cohort effect in adolescent smoking initiation in Wuhan, China.

Risks of smoking in treated and untreated older Chinese patients with isolated systolic hypertension

OBJECTIVES

To examine the health risks associated with smoking and blood pressure in Chinese hypertensive patients and to compare the benefit of antihypertensive drug treatment with the risk attributable to smoking.

METHODS

We used multiple Cox regression to correlate outcome with blood pressure and smoking status in 2284 older (aged > or = 60 years) patients enrolled in the Systolic Hypertension in China (Syst-China) Trial (systolic/diastolic blood pressure > or = 160/< 95 mmHg).

RESULTS

Median follow-up was 3.0 years. After adjustment for sex, age, active antihypertensive treatment and various entry characteristics, the relative hazard rates associated with smoking more than 20 cigarettes per day were 2.04 (P = 0.04), 4.66 (P < 0.001) and 4.74 (P = 0.002) for all-cause, noncardiovascular and cancer mortality, respectively. With similar adjustments applied, the relative hazard rates for total (fatal and non-fatal) stroke associated with smoking 10-20 and more than 20 cigarettes per day were 1.78 (P = 0.04) and 2.23 (P = 0.03), respectively. Furthermore, both smoking and systolic blood pressure were associated with higher risk of stroke. Compared with the overall risk in the whole group, treating 1,000 patients for 5 years prevented 40 [95% confidence interval (CI), 5-75] strokes in smokers as well as never smokers. Prognosis in never smokers and past smokers was similar. Quitting smoking had the potential to prevent 51 (95% CI, -21 to 122) strokes in untreated hypertensive patients and to prevent 45 (95% CI, - 14 to 104) additional strokes in treated patients, over and above the effects of antihypertensive treatment. If, in addition to stroke, non-cardiovascular mortality was also accounted for, the estimated absolute benefit of quitting smoking increased to 69 (95% CI, -18 to 155) and 97 (95% CI, 23-171) events in the untreated and the treated group, respectively.

CONCLUSIONS

In elderly Chinese patients, smoking was a risk factor for all-cause, non-cardiovascular and cancer mortality, as well as fatal and non-fatal stroke. The potential benefits of antihypertensive treatment and quitting smoking were approximately similar. In our view, these findings are important in terms of public health policies and health economics.

Lung cancer and environmental tobacco smoke in a non-industrial area of China

We report results from a population-based case-control study of lung cancer and environmental tobacco smoke (ETS) among never-smokers conducted in 2 rural prefectures of China, including 200 female and 33 male lung cancer cases, and 407 female and 114 male controls, matched on age, sex and prefecture of current residence. The odds ratio (OR) for ever-exposed to ETS was 1.19 (95% CI 0.7-2.0), with a significant trend (p<0.05) with increasing exposure. ORs were 1.00, 1.04, 1.13 and 1.51 for non-exposed, <10, 10-19 and >/=20 pack-years of ETS exposure, respectively. Excess risks were limited to ETS exposures in childhood (</=18 years of age). The OR for ever-exposed to ETS in childhood, adjusting for ETS exposure in adulthood, was 1. 52 (95% CI 1.1-2.2), with a significant trend (p<0.01) with increasing pack-years of childhood exposure, 1.00, 1.43, 1.81 and 2. 95, respectively. After adjustment for ETS in childhood, there was no excess risk from adult ETS exposure. The OR for ever-exposed to ETS in adulthood was 0.90 (95% CI 0.-1.4). These results were not affected by adjustment for type of residential dwelling, type or amount of fuel used, perceived indoor smokiness, or measures of socioeconomic status, or omitting next-of-kin respondents.

Smoking and women's health

Each year more than 600000 women have deaths associated with cigarette smoking. In addition, cigarette smoking is associated with a wide array of morbidities (such as osteoporosis, cardiovascular disease, and adverse pregnancy outcomes). Two hundred million women smoke worldwide, and this number appears to be rising, particularly in developing countries. Obstetrician-gynecologists can play a role in reducing morbidity and mortality from cigarette smoking by educating women about the dangers, advising them not to smoke, and assisting those who do smoke to quit.