Smoking behavior among adolescents in the city, suburbs, and rural areas of Shanghai

A Meta-Analysis of Cigarette Smoking Prevalence among Adolescents in China: 1981-2010

BACKGROUND

Systematic data regarding adolescent smoking are needed at the national level to support evidence-based tobacco control in China. The goal of this study was to estimate smoking prevalence among Chinese adolescents using published data.

METHODS

Published studies were located electronically from the commonly used databases in Chinese and English, complemented by manual searching. Forty-five studies were selected of the 9771 retrieved from the databases. These studies targeted adolescents aged 12-17 or middle/high school students, were conducted during the 1981-2010, and had adequate data for meta-analysis. The 45 selected studies covered 52 sites in different parts of China. Smoking rates were estimated using the sample-weighted and random effect method.

RESULTS

The estimated prevalence rate of lifetime smoking (ever smoked) varied within a narrow range (39.04%-46.03%) for males and progressively increased from 2.47% in 1981-1985 to 19.72% in 2001-2005 for females. The prevalence rate of current (30-day) smoking for males declined from 26.62% in 1981-1985 to 10.86% in 1996-2000 before increasing again. The prevalence of current smoking for females increased from 0.29% in 1981-1985 to 3.26% in 2006-2010.

CONCLUSIONS

The high levels of male smoking and the rapid increase in female smoking indicate growing burdens from tobacco-related diseases, underscoring the urgent need to strengthen adolescent tobacco control in China.

Family and personal protective factors moderate the effects of adversity and negative disposition on smoking among Chinese adolescents

Tobacco use among Chinese adolescents is increasing at approximately 80,000 new smokers per day. Assessing the causes for initiating tobacco use in China will be important in developing effective interventions and policies to stem rising prevalence rates. This study tested predictors of Resilience Theory in a sample of 602 Chinese adolescents. Results revealed that prior adversity, measured through school and family-related events, was significantly associated with increased smoking in females. Family factors (i.e., family cohesion, family adaptability, parental monitoring) and one personal factor (i.e., academic score) were associated with lower odds for smoking due to prior adversity and negative disposition.

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.

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.

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.

Project EX--a teen smoking cessation initial study in Wuhan, China

The increasing smoking prevalence in China indicates a need for effective smoking cessation programs, yet, to our knowledge, no studies have evaluated the effects of smoking cessation programs among Chinese adolescents. A group of 46 10th-grade-level cigarette smokers from two schools in Wuhan, China, were provided with Project EX, an eight-session school-based clinic smoking cessation program developed in the United States. Efforts of translation of the Project EX curriculum, verification of translation, curriculum modification, and cultural adaptation were made to adapt the curriculum to the local culture. The 46 smokers represented 71% of all the self-reported 30-day smokers among 622 10th graders at these two schools. Only one student dropped out from the clinic program. Four-month follow-up data indicated a 10.5% 30-day quit rate and a 14.3% 7-day quit rate. The students who did not quit smoking reported a 16% reduction in daily cigarette consumption at posttest and a 33% reduction at 4-month follow-up. Use of a 2 1/2-week prebaseline-to-baseline clinic assessment indicated a clinic cohort nonassisted quit rate of 3%. These data provided evidence that Project EX can be adapted in another country, such as China; can be very well received; and can lead to promising results on cessation.

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.

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.

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.

HPTLC screening assay for urinary cotinine as biomarker of environmental tobacco smoke exposure among male adolescents

For selective screening determination of urinary cotinine, i.e. (S)-1-methyl-5-(3-pyridyl)-2-pyrrolidinone, the major metabolite of nicotine, the high-performance thin-layer chromatographic (HPTLC) method have been proposed. Prior the final HPTLC analysis the procedure required a solid-phase extraction (SPE) of cotinine from collected urine samples with 1-methyl-2-pyrrolidinone as an internal standard. Densitometrical quantitation of cotinine on the chromatograms have been performed with a 16-grayscale scanner using the specialized software implemented on a desktop microcomputer. The lower detection limit of cotinine was 6 microg/l allowing the method to be applied for the measurement a concentration of this compound in urine samples collected from 35 elementary schoolboys exposed on both moderate and/or significant ETS. The mean recovery of cotinine from urine samples was 93%. The mean intra-day accuracy for the analysis of cotinine in range 6-750 microg/l. including four paralell measurements, was 2.9 %. The results of cotinine measurements by proposed SPE-HPTLC procedure were used in the pilot studies for assessment of hazard from home ETS on the health status of elementary schoolboys, especially an increased risk for infectious respiratory track diseases.