Determinants of smoking behaviour among adolescents in Semarang, Indonesia.

OBJECTIVES: To determine the smoking prevalence and to examine the determinants of smoking behaviour among male adolescents in Semarang, Indonesia. DESIGN: A random sample of schools in Semarang (population 1.5 million) was obtained using a stratified sampling procedure (strata based on type of school and district). A total of 149 schools were selected (response rate 72%). Within the schools 186 classes were selected, targeting the 11, 13, 15, and 17 year olds. An anonymous, self administered questionnaire was filled in by all students present at the day of the survey (total sample size 6276). OUTCOME MEASURES: Smoking prevalence, exposure to family and peer smoking, and other variables that may be related to smoking. Logistic regression was used to examine the determinants of smoking behaviour. Only male students were included in the analysis. RESULTS: Smoking increased dramatically between the ages of 11 and 17, from 8.2% to 38.7%. The variance explained by the regression model increased from 19.8% for 11 year olds to 53% for 17 year olds. The smoking behaviour of best friends was the most powerful determinant of smoking, and this was consistent across the age groups. Best friends' attitudes towards smoking and older brothers' smoking behaviour were also important determinants of smoking. CONCLUSIONS: Smoking prevalence among male adolescents in Semarang, Indonesia is high. Effective smoking prevention programmes should take into account the dominant influence of peers in the onset and maintenance of smoking behaviour. In general, school related items had a less important role in predicting smoking behaviour than expected.     

The first puff: forces in smoking initiation among Californians of Korean descent.

This study presents the correlates of initial exposure to cigarettes, variables associated with smoking prevalence and with continued smoking (or not) among adult Californians of Korean descent who have any initial exposure to cigarettes. Among those who have taken a puff, social contingencies contrast those who become current smokers from those who do not. Data were drawn from telephone interviews with adults (N = 2,830) developed from a random sampling of listed persons in California with Korean surnames during 2000-2001. Of the attempted interviews, 86% were completed; and 85% of the interviews were conducted in Korean. Nearly half of all respondents (49.0%) had been exposed to cigarettes, and 41.9% of these reported current smoking, according to Centers for Disease Control and Prevention criteria (currently smoke and have smoked 100 cigarettes during lifetime). Multivariate analysis suggests that social contingencies may influence both initial exposure to tobacco and continued smoking among Californians of Korean descent. Influences of acculturation on taking the first puff and on current smoking status diverged by gender. Social support increased the likelihood of the first puff among both genders, but the association was stronger among females than among males. Social reinforcers that lead to taking the first puff also discriminated between those who became current smokers and those who did not. Interventions should be directed at these variables among young Korean nonsmokers and new smokers.     

Association of post-treatment smoking change with future smoking and cessation efforts among adolescents with psychiatric comorbidity.

Little is known about how initial change following a smoking intervention relates to longer-term smoking outcomes among adolescent smokers with psychiatric comorbidity. The present study investigated this relationship among psychiatrically hospitalized adolescents (N = 183) who participated in a controlled trial comparing motivational interviewing to brief advice. Quit attempters (n = 37), reducers (n = 45), and maintainers (n = 101) were assembled based on, respectively, having made a quit attempt, having reduced smoking by at least 50%, and having reduced smoking by less than 50% in the first week after hospital discharge. Hierarchical linear models and generalized estimating equations were conducted to test group differences in average number of cigarettes per smoking day and odds of making a quit attempt during subsequent weeks of a 12-month continuous follow-up, and in cotinine-verified abstinence rates at 1, 6, and 12 months posthospitalization. Baseline smoking levels and presence of a substance use disorder or anxiety disorder were predictive of outcomes. After controlling for covariates, we found that quit attempters smoked less during follow-up than did the other change groups and that reducers smoked less than maintainers. Quit attempters evidenced a higher percentage of quit attempts during follow-up than did the other change groups. Reducers had a greater average percentage of quit attempts during follow-up than did maintainers. However, groups did not differ on cotinine-verified abstinence rates across the follow-up period. Findings have implications for initial post-treatment change as it relates to subsequent smoking and cessation outcomes among adolescent smokers at especially high risk for smoking persistence.     

Cough following initiation of smoking abstinence.

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

Competence skills help deter smoking among inner city adolescents

OBJECTIVE: To test whether higher levels of general competence are linked to more frequent use of refusal assertiveness that is in turn related to less subsequent smoking among inner city adolescents. METHODS: Longitudinal study conducted during three year middle school or junior high school period. A sample of 1459 students attending 22 middle (ages 11-14 years) and junior high (ages 12-15 years) schools in New York City participated. Students completed surveys at baseline, one year follow up, and two year follow up. The students self reported smoking, decision making skills, personal efficacy, and refusal assertiveness. Teams of three to five data collectors administered the questionnaire following a standardised protocol. These data were collected in school during a regular 40 minute class period. RESULTS: Based on the tested structural equation model, decision making and personal efficacy (that is, general competence) predicted higher refusal assertiveness and this greater assertiveness predicted less smoking at the two year follow up. The tested model had a good fit and was parsimonious and consistent with theory. CONCLUSIONS: Adolescent smoking prevention programmes often teach refusal skills in order to help youth resist peer pressure to smoke. The present findings suggest that teaching general competence skills as well may help to reduce smoking because youth with better personal efficacy and decision making skills are better able to implement smoking refusal strategies.     

Perceived importance of being thin and smoking initiation among young girls

Background: Smoking among adolescents remains unacceptably high and the difference in potential risk factors for smoking initiation between male and female adolescents has been explored. Although the association between smoking initiation and dieting behaviour has been observed among girls, the mechanism of the association is unknown.

Objective: To examine prospectively the association between perceived importance of being thin at baseline and smoking initiation among girls.

Design: A four year prospective cohort survey including perceived importance of being thin at baseline and smoking behaviour, conducted in 1993 and 1996.

Setting and participants: 273 Massachusetts female adolescents aged 12–15 years at baseline who reported having smoked no more than one cigarette by the time of the baseline survey, drawn from households sampled by random digit dialling.

Main outcome measure: Progression to established smoking, defined as having smoked 100 or more cigarettes in their lifetime.

Results: After adjusting for age, smoking status at baseline, and race/ethnicity, girls who valued thinness most strongly and somewhat strongly were both more likely to have become established smokers, compared to the girls who valued thinness least strongly. The odds ratios are 4.5 (95% confidence interval (CI), 1.4 to 16.7) and 3.4 (95% CI 1.04 to 10.9), respectively.

Conclusions: The level of perceived importance of being thin among young female adolescents predicts future smoking initiation. Smoking prevention programmes designed for female adolescents may therefore benefit from the inclusion of content related to importance of being thin.

     

Psychosocial predictors of cigarette smoking among adolescents living in public housing developments

BACKGROUND: Adolescents residing in low-income public housing developments in inner-city regions may be particularly vulnerable to a variety of risk factors associated with cigarette smoking. OBJECTIVE: To elucidate the aetiology of cigarette smoking among adolescents living in public housing developments. DESIGN, SETTING, AND SUBJECTS: We examined predictors of smoking from four domains: background characteristics, social influences, behavioural control, and psychosocial characteristics using a sample of seventh graders (mean age 12.9 years) who reside in public housing developments in New York City (n = 624). The addresses of participants in a larger investigation of the aetiology and prevention of smoking were checked to determine if they lived in one of 335 public housing developments in New York City. All participants living in public housing developments were included in the current study. MAIN OUTCOME MEASURES: African-American and Hispanic students completed questionnaires about their cigarette use, social pressures to smoke, smoking attitudes, smoking knowledge, and smoking resistance skills. Students also provided information on demographic and behavioural control (such as church and school attendance). RESULTS: Logistic regression analyses indicated that social influences from friends and family members predicted smoking. Psychosocial characteristics such as advertising resistance skills, anti-smoking attitudes, and refusal skills lowered the odds of smoking. CONCLUSIONS: These findings suggest that smoking prevention approaches targeted at these young people should increase their awareness of social pressures to smoke, correct misperceptions about the prevalence of smoking among friends, and teach relevant psychosocial skills.     

One-year predictors of smoking initiation and of continued smoking among elementary schoolchildren in multiethnic, low-income, inner-city neighbourhoods

OBJECTIVE—To identify one-year predictors of smoking initiation among never-smokers, and of continued smoking among ever-smokers.
DESIGN—Two sequential cohorts of grade 4 and 5 children. Data were collected as part of Coeur en sante St Louis du Parc, a non-randomised controlled trial to evaluate the impact of a school-based heart health promotion programme.
SETTING—24 inner-city elementary schools located in multiethnic, low-income neighbourhoods in Montreal.
SUBJECT—1824 schoolchildren aged 9-12 years with baseline and one-year follow-up data.
MAIN OUTCOME MEASURES—Changes in smoking behaviour over a year; the ability of baseline data to predict smoking initiation and continued smoking a year later was investigated in logistic regression analyses.
RESULTS—The prevalence of ever-smoking was 21.1% at baseline and 30.2% at one-year follow up. One in six never-smokers initiated smoking; one in three ever-smokers continued smoking. Predictors of initiation included age (odds ratio (OR) = 1.6, 95% confidence interval (CI) = 1.3 to 2.0), male gender (OR = 1.5 (95% CI = 1.1 to 2.0)), friends who smoke (OR = 2.3 (95% CI = 1.7 to 3.3)), sibling(s) who smoke (OR = 1.9 (95% CI = 1.2 to 3.1)), father/mother who smokes (OR = 2.2 (95% CI = 1.6 to 3.0)), and frequent high fat/"junk food" consumption (OR = 1.6 (95% CI = 1.1 to 2.1)). Age and friends who smoke were also independent predictors of continued smoking in both genders. In addition, in boys, current smokers at baseline were 2.6 times (95% CI = 1.4 to 5.0) more likely to continue smoking than past smokers. In girls, being overweight was associated with continued smoking (OR = 3.5 (95% CI = 1.6 to 7.6)).
CONCLUSIONS—Smoking prevention programmes should address parental and sibling influences on smoking, in addition to refusal skills training. Among girls, weight-related issues may also be important.


Keywords: children; smoking initiation predictors     

School smoking policies and smoking prevalence among adolescents: multilevel analysis of cross-sectional data from Wales

OBJECTIVE: To examine the association between school smoking policies and smoking prevalence among pupils. DESIGN: Multilevel analysis of cross-sectional data from surveys of schools and pupils. SETTING: 55 secondary schools in Wales. SUBJECTS: 55 teachers and 1375 pupils in year 11 (aged 15-16). MAIN OUTCOME MEASURES: Self-reported smoking behaviour. RESULTS: The prevalence of daily smoking in schools with a written policy on smoking for pupils, teachers, and other adults, with no pupils or teachers allowed to smoke anywhere on the school premises, was 9.5% (95% confidence interval (CI) 6.1% to 12.9%). In schools with no policy on pupils' or teachers' smoking, 30.1% (95% CI 23.6% to 36.6%) of pupils reported daily smoking. In schools with an intermediate level of smoking policy, 21.0% (95% CI 17.8% to 24.2%) smoked every day. School smoking policy was associated with school level variation in daily smoking (p = 0.002). In multilevel analysis, after adjusting for pupils' sex, parents' and best friends' smoking status, parental expectations, and alienation from school, there was less unexplained school level variation, but school smoking policy remained significant (p = 0.041). The association of smoking policy with weekly smoking was weaker than for daily smoking, and not significant after adjustment for pupil level variables. Both daily and weekly smoking prevalence were lower in schools where pupils' smoking restrictions were always enforced. Enforcement of teacher smoking restrictions was not significantly associated with pupils' smoking. CONCLUSIONS: This study demonstrates an association between policy strength, policy enforcement, and the prevalence of smoking among pupils, after having adjusted for pupil level characteristics. These findings suggest that the wider introduction of comprehensive school smoking policies may help reduce teenage smoking.     

Seasonal variations of the sugars in birch sap

The content of the main sugars of birch sap (Betula pendula Roth. and B. pubescens Ehrh.), which will be used for syrup production in Finland, were monitored by GLC as TMS-derivatives. Glucose and fructose had a concentration maximum at the end of April or at the beginning of May (5–8 g litre⁻¹). This sugar can be regarded as invert sugar. The content of sucrose (0–0·7 g litre⁻¹) decreased and in many cases it had totally disappeared by April. A correlation between sucrose and other sugars was not observed. The concentration of galactose was always low (0·01–0·03 g litre⁻¹). No diurnal variation was observed in the content of any sugar. The highest sap flow was obtained in the third flow week at the end of April and more than one-third of the total sugar yield could be collected during that period.     

Current smoking among young adolescents: assessing school based contextual norms

Objective: To extend research on the relation of school based contextual norms to current smoking among adolescents by using three analytic techniques to test for contextual effects. It was hypothesised that significant contextual effects would be found in all three models, but that the strength of these effects would vary by the statistical rigor of the model.

Design: Three separate analytic approaches were conducted on baseline self report student survey data from a larger study to test the relation between school level perceived peer tobacco use and individual current smoking status.

Participants: A representative sample of 5399 sixth through eighth grade students in 14 midwestern middle schools completed the survey. All enrolled sixth through eighth grade students were eligible to participate in the survey. The student participation rate was 91.4% for the entire sample, and did not differ significantly between the schools (range 82–100%).

Main outcome measure: Thirty day cigarette smoking prevalence.

Results: A level 2 only model based on aggregated individual responses indicated that students in schools with higher average reported peer tobacco use were more likely to be current smokers than students in schools with lower average peer tobacco use. Using a level 1 only model based on individual responses indicated that the effect of school level perceived peer tobacco use on current smoking was significant when individual perceived peer tobacco use was excluded from the model but was non-significant when individual perceived peer tobacco use was added to the model. A multilevel model also indicated that the effect of school level perceived peer tobacco use on current smoking was not significant when individual perceived peer tobacco use was added to the model.

Conclusion: The analytic approach used to examine contextual effects using individuals' reports of peer tobacco use norms that were aggregated to obtain a context measure of the school norms may produce statistical artefacts that distort the association of the school context in general, and peer tobacco use norms in particular, with increased risk for current smoking beyond the risk associated with individual factors.

     

Cigarette and waterpipe smoking among Lebanese adolescents, a cross-sectional study, 2003-2004.

Waterpipe or "argileh" is a form of smoking other than cigarettes that is currently spreading among people of all ages. The objective of the present study was to assess tobacco smoking practices (waterpipe and/or cigarette) among public and private adolescent school students in Beirut, Lebanon. A sample of 2,443 students selected from 10 private and 3 public schools with intermediate/secondary classes filled out a self-administered anonymous questionnaire that inquired about sociodemographic characteristics, and behavior about tobacco smoking. Binary analysis was performed as well as three regression models for the relationship between exclusive cigarettes smoking, exclusive waterpipe smoking and both cigarettes and waterpipe as the dependent variables and gender, type of school, and class as the independent variables. The current prevalence of cigarettes smoking was 11.4%, and that of waterpipe smoking was 29.6%. Gender was significantly associated with cigarettes (OR=3.2, 95% CI 1.8-5.6) but not waterpipe smoking. Public school students were, respectively, 3.2 (95% CI 1.8-5.6) and 1.7 (95% CI 1.4-2.1) times more likely to be exclusive cigarettes smokers, and exclusive waterpipe smokers. Class was not significantly associated with exclusive cigarette smoking; however, students attending secondary classes were 1.3 (95% CI 1.1-1.6) times more likely to be exclusive waterpipe smokers. The reasons behind the high prevalence of both types of smoking are presented and discussed. The present study calls for school-based prevention programs and other types of interventions such as tax increases, and age-restrictions on tobacco sales. More aggressive interventions to disseminate education and awareness among parents and students altogether are warranted.     

Seasonal variations in the chlorogenic acids content of tea

Quantitative estimation of chlorogenic acids in tea leaf (Camellia sinensis) at different stages of its development and during the harvesting season by application of thin layer chromatography has revealed that the stem contains the highest concentration of the acids. The concentration of the acids in plucking shoots, which comprise the terminal two leaves and the growing bud, varies during the harvesting season and is maximum in the monsoon season.     

Seasonal variations in the chemical composition of camel milk in Jordan

The principal chemical components of milk from the Arabian camel (Camelus dromedarius) were monitored in Jordan over one year. The analyses included total solids, fat, protein, vitamins, minerals and organic acids. Large seasonal variations in total solids and fat were apparent, with maxima in mid-winter of 139 and 39.0 g/l, respectively, and minima in August of 102 and 25.0 g/l. These differences may be sufficient to alter the sensory properties of the milk, and the fat: casein ratio may need standardisation for cheesemaking. The mean values of trace elements like zinc (5.8 mg/l), iron (4.4 mg/l) and manganese (0.05 mg/l) in Jordanian camel milk could provide valuable additions to the diet of urban populations, as could the mean concentration of vitamin C (33 mg/l). The levels of organic acids were generally higher than in bovine milk and, as with all the constituents of the milk, there were discernible patterns linking concentration and season of the year.     

A mass media programme to prevent smoking among adolescents: costs and cost effectiveness

OBJECTIVE: To examine costs and cost-effectiveness ratios of a four- year mass media programme previously shown to prevent the onset of smoking among adolescents. DESIGN: A matched control design. SETTING: Two cities in Montana, one in New York and one in Vermont, USA. SUBJECTS: Students in grades 10-12 (ages 15-18). INTERVENTION: A four- year mass media campaign to prevent the onset of smoking. MAIN OUTCOME MEASURES: Cost per student potentially exposed to the mass media campaign; cost per student smoker potentially averted; and cost per life-year gained. Cost estimates were also made for a similar campaign that would be broadcast nationally in the United States. RESULTS: In 1996 dollars, the cost of developing and broadcasting the mass media campaign was $759,436, and the cost per student potentially exposed to the campaign (n = 18,600) was $41. The cost per student smoker averted (n = 1023) was $754 (95% confidence interval (CI) = $531-$1296). The cost per life-year gained discounted at 3% over the life expectancy for young adult smokers was $696 (95% CI = $445-$1269). The estimated cost of developing and broadcasting a similar four-year mass media campaign in all 209 American media markets would be approximately $84.5 million, at a cost of $8 per student potentially exposed to a national campaign, $162 per student smoker averted, and $138 (95% CI = $88-$252) per life- year gained. CONCLUSION: Estimates of the cost-effectiveness ratios of this mass media campaign in preventing the onset of smoking showed it to be economically attractive and to compare favourably with other preventive and therapeutic strategies.


     

The moderating effects of religiosity on the genetic and environmental determinants of smoking initiation.

Although a number of studies have shown that various measures of religiosity are inversely correlated with smoking behavior, none of these studies have used genetically informative samples to test for a gene-environment interaction between the determinants of smoking initiation and religiosity. We tested the moderating effects of three measures of religiosity (religious affiliation, organizational religious activity, and self-rated religiousness) on the genetic and environmental determinants of smoking initiation in 237 monozygotic twin pairs, 315 dizygotic twin pairs, 779 full-sibling pairs, and 233 half-sibling pairs in young adults surveyed from the third wave of the National Longitudinal Study of Adolescent Health. Primary analyses incorporated all sibling pairs, irrespective of whether they were concordant or discordant for the environmental moderator, in models designed to account for the confounding effects of a gene-environment correlation. High levels of self-rated religiousness attenuated the additive genetic component for smoking initiation and were associated with a lower prevalence of smoking initiation. Although all three measures of religiosity were associated with lower rates of smoking initiation, only self-rated religiousness moderated genetic influences on the liability for smoking.