An assessment of nicotine dependence among pregnant adolescents

Comparison of the Fagerström Test for Cigarette Dependence and the Heaviness of Smoking Index in the Second and Third Trimester of Pregnancy

Introduction

Smoking cessation at any stage of pregnancy can benefit the mother and fetus. Cigarette dependence is a significant factor in women who continue to smoke during pregnancy and accurate assessment of cigarette dependence can be helpful in planning smoking cessation programs. The objective of our study was to investigate the validity of the Fagerstrom Test for Cigarette Dependence (FTCD) and Heaviness of Smoking Index (HSI) as measures of cigarette dependence in the second and third trimesters of pregnancy by comparing them to serum cotinine levels.

Methods

Prospective cohort study of 167 women in their second and third trimester of pregnancy who self-reported cigarette smoking. They were administered the FTCD questionnaire and blood was drawn for cotinine measurements using a direct enzyme linked immunoassay. Linear regression was used to adjust for maternal age, body mass index, gestation, and parity to investigate the association between cotinine levels and the two scores.

Results

Both the FTCD and HSI correlated significantly with serum cotinine levels (Spearman coefficient 0.42 and 0.37, respectively, p < .001). The correlation coefficients of both scores were higher in primigravidas (n = 51) compared to multigravidas, but the difference was statistically nonsignificant. Using multiple linear regression, both scores were significantly related to serum cotinine levels. For each unit increase in the FTCD and HSI, the serum cotinine level increased by 21.4 ng/mL (95% confidence interval 10.1-32.7, p <0.001) and 37 ng/mL (95% confidence interval 18.6-55.4, p < 0.001), respectively.

Conclusions

Both the FTCD and HSI can be used to assess cigarette dependence in the second and third trimester of pregnancy.

Implications

There is lack of data on the validity of the FTCD and the HSI as markers of cigarette dependence during the second and third trimester of pregnancy. Our study suggests that both the FTCD and HSI perform well in assessing cigarette dependence in the second and third trimester of pregnancy and can be used to plan smoking cessation programs.

Psychosocial interventions for supporting women to stop smoking in pregnancy

BACKGROUND

Tobacco smoking remains one of the few preventable factors associated with complications in pregnancy, and has serious long-term implications for women and babies. Smoking in pregnancy is decreasing in high-income countries, but is strongly associated with poverty and is increasing in low- to middle-income countries.

OBJECTIVES

To assess the effects of smoking cessation interventions during pregnancy on smoking behaviour and perinatal health outcomes.

SEARCH METHODS

In this sixth update, we searched the Cochrane Pregnancy and Childbirth Group's Trials Register (13 November 2015), checked reference lists of retrieved studies and contacted trial authors.

SELECTION CRITERIA

Randomised controlled trials, cluster-randomised trials, and quasi-randomised controlled trials of psychosocial smoking cessation interventions during pregnancy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and trial quality, and extracted data. Direct comparisons were conducted in RevMan, with meta-regression conducted in STATA 14.

MAIN RESULTS

The overall quality of evidence was moderate to high, with reductions in confidence due to imprecision and heterogeneity for some outcomes. One hundred and two trials with 120 intervention arms (studies) were included, with 88 trials (involving over 28,000 women) providing data on smoking abstinence in late pregnancy. Interventions were categorised as counselling, health education, feedback, incentives, social support, exercise and dissemination.In separate comparisons, there is high-quality evidence that counselling increased smoking cessation in late pregnancy compared with usual care (30 studies; average risk ratio (RR) 1.44, 95% confidence interval (CI) 1.19 to 1.73) and less intensive interventions (18 studies; average RR 1.25, 95% CI 1.07 to 1.47). There was uncertainty whether counselling increased the chance of smoking cessation when provided as one component of a broader maternal health intervention or comparing one type of counselling with another. In studies comparing counselling and usual care (largest comparison), it was unclear whether interventions prevented smoking relapse among women who had stopped smoking spontaneously in early pregnancy. However, a clear effect was seen in smoking abstinence at zero to five months postpartum (11 studies; average RR 1.59, 95% CI 1.26 to 2.01) and 12 to 17 months (two studies, average RR 2.20, 95% CI 1.23 to 3.96), with a borderline effect at six to 11 months (six studies; average RR 1.33, 95% CI 1.00 to 1.77). In other comparisons, the effect was unclear for most secondary outcomes, but sample sizes were small.Evidence suggests a borderline effect of health education compared with usual care (five studies; average RR 1.59, 95% CI 0.99 to 2.55), but the quality was downgraded to moderate as the effect was unclear when compared with less intensive interventions (four studies; average RR 1.20, 95% CI 0.85 to 1.70), alternative interventions (one study; RR 1.88, 95% CI 0.19 to 18.60), or when smoking cessation health education was provided as one component of a broader maternal health intervention.There was evidence feedback increased smoking cessation when compared with usual care and provided in conjunction with other strategies, such as counselling (average RR 4.39, 95% CI 1.89 to 10.21), but the confidence in the quality of evidence was downgraded to moderate as this was based on only two studies and the effect was uncertain when feedback was compared to less intensive interventions (three studies; average RR 1.29, 95% CI 0.75 to 2.20).High-quality evidence suggests incentive-based interventions are effective when compared with an alternative (non-contingent incentive) intervention (four studies; RR 2.36, 95% CI 1.36 to 4.09). However pooled effects were not calculable for comparisons with usual care or less intensive interventions (substantial heterogeneity, I2 = 93%).High-quality evidence suggests the effect is unclear in social support interventions provided by peers (six studies; average RR 1.42, 95% CI 0.98 to 2.07), in a single trial of support provided by partners, or when social support for smoking cessation was provided as part of a broader intervention to improve maternal health.The effect was unclear in single interventions of exercise compared to usual care (RR 1.20, 95% CI 0.72 to 2.01) and dissemination of counselling (RR 1.63, 95% CI 0.62 to 4.32).Importantly, high-quality evidence from pooled results demonstrated that women who received psychosocial interventions had a 17% reduction in infants born with low birthweight, a significantly higher mean birthweight (mean difference (MD) 55.60 g, 95% CI 29.82 to 81.38 g higher) and a 22% reduction in neonatal intensive care admissions. However the difference in preterm births and stillbirths was unclear. There did not appear to be adverse psychological effects from the interventions.The intensity of support women received in both the intervention and comparison groups has increased over time, with higher-intensity interventions more likely to have higher-intensity comparisons, potentially explaining why no clear differences were seen with increasing intervention intensity in meta-regression analyses. Among meta-regression analyses: studies classified as having 'unclear' implementation and unequal baseline characteristics were less effective than other studies. There was no clear difference between trials implemented by researchers (efficacy studies), and those implemented by routine pregnancy staff (effectiveness studies), however there was uncertainty in the effectiveness of counselling in four dissemination trials where the focus on the intervention was at an organisational level. The pooled effects were similar in interventions provided for women classified as having predominantly low socio-economic status, compared to other women. The effect was significant in interventions among women from ethnic minority groups; however not among indigenous women. There were similar effect sizes in trials with biochemically validated smoking abstinence and those with self-reported abstinence. It was unclear whether incorporating use of self-help manuals or telephone support increased the effectiveness of interventions.

AUTHORS' CONCLUSIONS

Psychosocial interventions to support women to stop smoking in pregnancy can increase the proportion of women who stop smoking in late pregnancy and the proportion of infants born low birthweight. Counselling, feedback and incentives appear to be effective, however the characteristics and context of the interventions should be carefully considered. The effect of health education and social support is less clear. New trials have been published during the preparation of this review and will be included in the next update.

Tobacco and alcohol use in the context of adolescent pregnancy and postpartum: a scoping review of the literature

Adolescent girls are more likely than women of other ages to smoke tobacco or drink alcohol during pregnancy. The health impacts of smoking and drinking for girls and the interconnections between alcohol and tobacco use with adolescent pregnancy underscore the urgent need for integrated approaches to prevent and reduce alcohol and tobacco use among pregnant girls/young women. This article reports on the results of a scoping review of the literature focused on adolescents' use of tobacco and alcohol during pregnancy and postpartum. A search of CINAHL, Medline, Social Science Index and Web of Science identified 40 articles published in the two decades between 1990 and 2012 that met our inclusion criteria related to this age group, pregnancy/motherhood status, and use of both alcohol and tobacco. The review points to compelling gaps in our knowledge and our responsiveness to adolescents aged 19 and under who use alcohol and tobacco during pregnancy and the postpartum period. Research has been primarily descriptive, with separate, parallel streams of investigation to identify trends and predictors of alcohol and tobacco use, prior to, during and following pregnancy. There is a marked lack of effective interventions described in the literature that are designed to prevent or reduce alcohol and tobacco use during pregnancy among adolescent girls; and there are few examples of gender-informed prevention or treatment programmes for this population. Research is needed on interventions that attend to the context of adolescent girls' substance use as well as their preferences and developmental needs for support that encourage sustained behaviour change throughout pregnancy and the postpartum period and that effectively address the influence of partners and friends on use.

Psychosocial interventions for supporting women to stop smoking in pregnancy

BACKGROUND

Tobacco smoking in pregnancy remains one of the few preventable factors associated with complications in pregnancy, stillbirth, low birthweight and preterm birth and has serious long-term implications for women and babies. Smoking in pregnancy is decreasing in high-income countries, but is strongly associated with poverty and increasing in low- to middle-income countries.

OBJECTIVES

To assess the effects of smoking cessation interventions during pregnancy on smoking behaviour and perinatal health outcomes.

SEARCH METHODS

In this fifth update, we searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 March 2013), checked reference lists of retrieved studies and contacted trial authors to locate additional unpublished data.

SELECTION CRITERIA

Randomised controlled trials, cluster-randomised trials, randomised cross-over trials, and quasi-randomised controlled trials (with allocation by maternal birth date or hospital record number) of psychosocial smoking cessation interventions during pregnancy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and trial quality, and extracted data. Direct comparisons were conducted in RevMan, and subgroup analyses and sensitivity analysis were conducted in SPSS.

MAIN RESULTS

Eighty-six trials were included in this updated review, with 77 trials (involving over 29,000 women) providing data on smoking abstinence in late pregnancy.In separate comparisons, counselling interventions demonstrated a significant effect compared with usual care (27 studies; average risk ratio (RR) 1.44, 95% confidence interval (CI) 1.19 to 1.75), and a borderline effect compared with less intensive interventions (16 studies; average RR 1.35, 95% CI 1.00 to 1.82). However, a significant effect was only seen in subsets where counselling was provided in conjunction with other strategies. It was unclear whether any type of counselling strategy is more effective than others (one study; RR 1.15, 95% CI 0.86 to 1.53). In studies comparing counselling and usual care (the largest comparison), it was unclear whether interventions prevented smoking relapse among women who had stopped smoking spontaneously in early pregnancy (eight studies; average RR 1.06, 95% CI 0.93 to 1.21). However, a clear effect was seen in smoking abstinence at zero to five months postpartum (10 studies; average RR 1.76, 95% CI 1.05 to 2.95), a borderline effect at six to 11 months (six studies; average RR 1.33, 95% CI 1.00 to 1.77), and a significant effect at 12 to 17 months (two studies, average RR 2.20, 95% CI 1.23 to 3.96), but not in the longer term. In other comparisons, the effect was not significantly different from the null effect for most secondary outcomes, but sample sizes were small.Incentive-based interventions had the largest effect size compared with a less intensive intervention (one study; RR 3.64, 95% CI 1.84 to 7.23) and an alternative intervention (one study; RR 4.05, 95% CI 1.48 to 11.11).Feedback interventions demonstrated a significant effect only when compared with usual care and provided in conjunction with other strategies, such as counselling (two studies; average RR 4.39, 95% CI 1.89 to 10.21), but the effect was unclear when compared with a less intensive intervention (two studies; average RR 1.19, 95% CI 0.45 to 3.12).The effect of health education was unclear when compared with usual care (three studies; average RR 1.51, 95% CI 0.64 to 3.59) or less intensive interventions (two studies; average RR 1.50, 95% CI 0.97 to 2.31).Social support interventions appeared effective when provided by peers (five studies; average RR 1.49, 95% CI 1.01 to 2.19), but the effect was unclear in a single trial of support provided by partners.The effects were mixed where the smoking interventions were provided as part of broader interventions to improve maternal health, rather than targeted smoking cessation interventions.Subgroup analyses on primary outcome for all studies showed the intensity of interventions and comparisons has increased over time, with higher intensity interventions more likely to have higher intensity comparisons. While there was no significant difference, trials where the comparison group received usual care had the largest pooled effect size (37 studies; average RR 1.34, 95% CI 1.25 to 1.44), with lower effect sizes when the comparison group received less intensive interventions (30 studies; average RR 1.20, 95% CI 1.08 to 1.31), or alternative interventions (two studies; average RR 1.26, 95% CI 0.98 to 1.53). More recent studies included in this update had a lower effect size (20 studies; average RR 1.26, 95% CI 1.00 to 1.59), I(2)= 3%, compared to those in the previous version of the review (50 studies; average RR 1.50, 95% CI 1.30 to 1.73). There were similar effect sizes in trials with biochemically validated smoking abstinence (49 studies; average RR 1.43, 95% CI 1.22 to 1.67) and those with self-reported abstinence (20 studies; average RR 1.48, 95% CI 1.17 to 1.87). There was no significant difference between trials implemented by researchers (efficacy studies), and those implemented by routine pregnancy staff (effectiveness studies), however the effect was unclear in three dissemination trials of counselling interventions where the focus on the intervention was at an organisational level (average RR 0.96, 95% CI 0.37 to 2.50). The pooled effects were similar in interventions provided for women with predominantly low socio-economic status (44 studies; average RR 1.41, 95% CI 1.19 to 1.66), compared to other women (26 studies; average RR 1.47, 95% CI 1.21 to 1.79); though the effect was unclear in interventions among women from ethnic minority groups (five studies; average RR 1.08, 95% CI 0.83 to 1.40) and aboriginal women (two studies; average RR 0.40, 95% CI 0.06 to 2.67). Importantly, pooled results demonstrated that women who received psychosocial interventions had an 18% reduction in preterm births (14 studies; average RR 0.82, 95% CI 0.70 to 0.96), and infants born with low birthweight (14 studies; average RR 0.82, 95% CI 0.71 to 0.94). There did not appear to be any adverse effects from the psychosocial interventions, and three studies measured an improvement in women's psychological wellbeing.

AUTHORS' CONCLUSIONS

Psychosocial interventions to support women to stop smoking in pregnancy can increase the proportion of women who stop smoking in late pregnancy, and reduce low birthweight and preterm births.

Nicotine dependence and biochemical exposure measures in the second trimester of pregnancy

Introduction:

The Heaviness of Smoking Index (HSI) is validated to measure nicotine dependence in nonpregnant smokers, and in these smokers, mean salivary and serum cotinine levels are related by a ratio of 1.25. However, as nicotine metabolism increases during gestation, these findings may differ in pregnancy. We investigated the validity of HSI in pregnancy by comparing this with 3 biochemical measures; in a search for a less-invasive cotinine measure in pregnancy, we also explored the relationship between mean blood and salivary cotinine levels.

Methods:

Cross-sectional analyses using baseline data from the Smoking, Nicotine, and Pregnancy Trial. Participants were 16–46 years old, 12–24 weeks gestation, smoked more than 5 cigarettes per day, and had exhaled carbon monoxide (CO) readings of at least 8 ppm. Linear regression was used to examine correlations between HSI and blood cotinine and salivary cotinine and exhaled CO. Correlation between blood and salivary cotinine was investigated using linear regression through the origin.

Results:

HSI scores were associated with blood cotinine (R² = 0.20, n = 662, p < .001), salivary cotinine (R² = 0.11, n = 967, p < .001), and exhaled CO (R² = 0.13, n = 1,050, p < .001). Salivary and blood cotinine levels, taken simultaneously, were highly correlated (R² = 0.91, n = 628, p < .001) and the saliva:blood level ratio was 1.01 (95% CI 0.99–1.04).

Conclusions:

Correlations between HSI and biochemical measures in pregnancy were comparable with those obtained outside pregnancy, suggesting that HSI has similar validity in pregnant smokers. Salivary and blood cotinine levels are roughly equivalent in pregnant smokers.

Tobacco withdrawal symptoms and urges to smoke in pregnant versus non-pregnant smokers

We compared tobacco withdrawal in pregnant and non-pregnant smokers abstaining from smoking for 24h. Female smokers completed an internet-based questionnaire, including the Minnesota Nicotine Withdrawal Scale-Revised (MNWS). They also rated additional withdrawal items and strength of urge to smoke. Consenting women were randomized to either: (i) abstain from smoking for 24h or (ii) smoke as usual. After 24h they rated their withdrawal again. We included a 'smoking as usual' group as we wished to establish that smoking abstinence increased withdrawal symptoms. Two-hundred and seventy-five women completed both the initial and the 24h questionnaire and reported abstaining (n=115, 17% pregnant) or smoking (n=160, 21% pregnant) as requested. Exclusively among abstinent smokers, we compared symptoms for the pregnant and non-pregnant groups. After 24h pregnant women had significantly lower scores than non-pregnant women for the mean MNWS (p=0.004) and for three individual MNWS symptoms (angry, p=0.010; anxious, p=0.048; impatient, p=0.011), with adjustments for baseline cigarette consumption and baseline withdrawal scores. Overall, on the first day of smoking abstinence, pregnant women are likely to report less severe tobacco withdrawal than non-pregnant women.

Nicotine dependence among rural-urban migrants in China

Background

The complex mechanism of nicotine dependency makes it challenging to evaluate dependence or progress towards dependence. The aim of this study was to estimate nicotine dependence levels and identify determinants of dependence among Chinese rural-urban migrants.

Methods

Multi-stage systematic sampling was used to select 4,198 rural-urban migrants aged 18 years or older from three metropolises in China. A structured questionnaire was administered during face-to-face interviews. Nicotine dependence among participants was assessed by means of the six-item Mandarin Chinese Version of the Fagerström Test for Nicotine Dependence (CFTND). Determinants of dependence were analyzed using multivariate analysis of variance (MANOVA).

Results

Among 4,198 participants, estimated current, daily, and occasional smoking rates were 28.3%, 21.2%, and 7.1%, respectively. The CTFND score for the 894 daily smokers was 3.39(SD: 2.32). MANOVA showed that work type, age at first migration, length of migration, and number of cities ever lived were associated with nicotine dependence.

Conclusion

A migratory lifestyle is associated with nicotine dependence. Results could inform the design of tobacco control programs that target Chinese rural-urban migrant workers as a special at-risk population.

Interventions for promoting smoking cessation during pregnancy

BACKGROUND

Tobacco smoking in pregnancy remains one of the few preventable factors associated with complications in pregnancy, low birthweight, preterm birth and has serious long-term health implications for women and babies. Smoking in pregnancy is decreasing in high-income countries and increasing in low- to middle-income countries and is strongly associated with poverty, low educational attainment, poor social support and psychological illness.

OBJECTIVES

To assess the effects of smoking cessation interventions during pregnancy on smoking behaviour and perinatal health outcomes.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (June 2008), the Cochrane Tobacco Addiction Group's Trials Register (June 2008), EMBASE, PsycLIT, and CINAHL (all from January 2003 to June 2008). We contacted trial authors to locate additional unpublished data.

SELECTION CRITERIA

Randomised controlled trials where smoking cessation during pregnancy was a primary aim of the intervention.

DATA COLLECTION AND ANALYSIS

Trials were identified and data extracted by one person and checked by a second. Subgroup analysis was conducted to assess the effect of risk of trial bias, intensity of the intervention and main intervention strategy used.

MAIN RESULTS

Seventy-two trials are included. Fifty-six randomised controlled trials (over 20,000 pregnant women) and nine cluster-randomised trials (over 5000 pregnant women) provided data on smoking cessation outcomes.There was a significant reduction in smoking in late pregnancy following interventions (risk ratio (RR) 0.94, 95% confidence interval (CI) 0.93 to 0.96), an absolute difference of six in 100 women who stopped smoking during pregnancy. However, there is significant heterogeneity in the combined data (I(2) > 60%). In the trials with the lowest risk of bias, the interventions had less effect (RR 0.97, 95% CI 0.94 to 0.99), and lower heterogeneity (I(2) = 36%). Eight trials of smoking relapse prevention (over 1000 women) showed no statistically significant reduction in relapse.Smoking cessation interventions reduced low birthweight (RR 0.83, 95% CI 0.73 to 0.95) and preterm birth (RR 0.86, 95% CI 0.74 to 0.98), and there was a 53.91g (95% CI 10.44 g to 95.38 g) increase in mean birthweight. There were no statistically significant differences in neonatal intensive care unit admissions, very low birthweight, stillbirths, perinatal or neonatal mortality but these analyses had very limited power.

AUTHORS' CONCLUSIONS

Smoking cessation interventions in pregnancy reduce the proportion of women who continue to smoke in late pregnancy, and reduce low birthweight and preterm birth. Smoking cessation interventions in pregnancy need to be implemented in all maternity care settings. Given the difficulty many pregnant women addicted to tobacco have quitting during pregnancy, population-based measures to reduce smoking and social inequalities should be supported.

Risk factors for young adult substance use among women who were teenage mothers

Teenage mothers may not "mature out" of substance use during young adulthood, and this non-normative trajectory of use may contribute to negative outcomes for teenage mothers and their offspring. Pregnant teenagers (age range=12-18 years; 68% Black) were recruited from a prenatal clinic and interviewed about their substance use, and subsequently re-interviewed six and ten years later (n=292). Consistent with the literature, early tobacco and marijuana use were risk factors for young adult use. Other substance use, peer adolescent use and mental health indicators were more important than race and socioeconomic status (SES) in determining which teenage mothers would use tobacco, engage in binge drinking, and use marijuana as young adults. However, race and SES were significant predictors of quitting tobacco use and marijuana use by the 10-year follow-up. Depression was associated with both persistent tobacco use and marijuana use in teenage mothers. These results illustrate the long-term consequences of teenage childbearing and identify modifiable risk factors for later health risks that should be addressed among younger mothers.

Examining smoking and cessation during pregnancy among an Appalachian sample: a preliminary view

BACKGROUND

Several transitions that a woman experiences prenatally may influence her desire or ability to discontinue smoking. This study explores the role of smoking for young, Appalachian, nulliparous pregnant women and their plans for smoking during their pregnancies.

RESULTS

The reports of women and their male partners were taken from baseline interviews conducted during the first trimester of pregnancy. Cigarette smoking appeared to be more than an isolated addictive activity; rather, smoking was interwoven in women's social and personal realms, often changing as their perceptions of self changed. Women and their partners who continued to smoke appeared to be depressed, reject authority, and perceived little control over issues related to being pregnant.

CONCLUSION

These findings support the argument that standard substance use treatments and polices based on stages-of-change theories may not be effective for all individuals particularly those experiencing significant developmental changes in their lives. Greater success might be obtained from treatment programs designed to recognize the impact of these transitions as it relates to the substance use. The changing experiences of pregnant women in terms of their identity development, views of others, and their relationships have not been adequately addressed in existing cessation programs. Empirically-based interventions targeting these lifestyle characteristics may lead to increased cessation success among pregnant women.

Characterizing nicotine withdrawal in pregnant cigarette smokers

Maternal smoking is a leading preventable cause of poor pregnancy outcomes and infant morbidity and mortality. Whereas pregnancy has been thought of as a "window of opportunity" when women are more motivated to change health behaviors such as smoking, only 20% of pregnant women quit smoking upon learning they are pregnant and remain abstinent at the end of the pregnancy. Greater understanding of possible obstacles to smoking during pregnancy, such as nicotine withdrawal, is needed. The symptoms of nicotine withdrawal have been well characterized in nonpregnant smokers, but there has been only 1 report conducted during pregnancy, and that was a retrospective study. The aim of the present study was to characterize nicotine withdrawal and craving in pregnant cigarette smokers. These data were collected as part of prospective clinical trials assessing the efficacy of voucher-based incentives to promote abstinence from cigarette smoking during pregnancy and postpartum. The authors examined results from the Minnesota Nicotine Withdrawal Scale (J. R. Hughes & D. K. Hatsukami, 1998) in 27 abstainers (reported no or very low levels of smoking, which was confirmed biochemically) and 21 smokers (smoked at >80% of their baseline smoking level) during the first 5 days of a cessation attempt. Abstainers reported more impatience, anger, and difficulty concentrating than did smokers. The results also suggest that pregnant smokers generally may have elevated baseline levels of withdrawal, which need to be considered in the design and analysis of future studies.

Smoking cessation strategy use among pregnant ex-smokers

There is strong evidence for the beneficial health effects associated with smoking cessation during pregnancy. Although many pregnant women spontaneously quit smoking during pregnancy, postpartum relapse is high. Evidence suggests that pregnant women do not use smoking cessation strategies as identified by the 40-item Processes of Change Scale as frequently as others who quit smoking. The purpose of this study is to identify factors associated with pregnant exsmokers' use of experiential and behavioral smoking cessation strategies. A cross-sectional survey design is used for the study. From a sample of 201 primarily low-income pregnant women recruited to participate in a larger study, 58 were biologically confirmed ex-smokers. Multiple regression analysis reveals that motivation to quit smoking is the only significant factor explaining the use of experiential and behavioral smoking cessation strategies, accounting for 44% of the variance in experiential processes and 31% of the variance in behavioral processes.

Development of a multidimensional measure of tobacco dependence in adolescence

The objective of this research was to develop a multidimensional measure of tobacco dependence, sensitive to signs of incipient dependence and relevant to adolescents. A cross-sectional survey was conducted of students attending randomly selected high schools in two regions of British Columbia, Canada. Of the 3280 adolescents who completed the survey, 17% (n=562) indicated that they had smoked at least once in the month preceding the survey and were classified as "smokers." Ninety-one percent of the smokers (n=513) completed all or most of the items and comprised the sample for the analysis. The survey included a number of items related to smoking status and nicotine dependence, including the newly developed Dimensions of Tobacco-Dependence Scale (DTDS), a 54-item multidimensional measure of tobacco dependence. Exploratory factor analyses using MINRES was used to examine the dimensions of the DTDS. The measure was found to include four dimensions: social reinforcement, emotional reinforcement, sensory reinforcement, and physical reinforcement. All subscales had adequate reliability (Cronbach's alpha coefficients >.70).

Interventions for promoting smoking cessation during pregnancy

BACKGROUND

Smoking remains one of the few potentially preventable factors associated with low birthweight, preterm birth and perinatal death.

OBJECTIVES

To assess the effects of smoking cessation programs implemented during pregnancy on the health of the fetus, infant, mother, and family.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Tobacco Addiction Group trials register (July 2003), MEDLINE (January 2002 to July 2003), EMBASE (January 2002 to July 2003), PsychLIT (January 2002 to July 2003), CINAHL (January 2002 to July 2003), and AUSTHEALTH (January 2002 to 2003). We contacted trial authors to locate additional unpublished data. We handsearched references of identified trials and recent obstetric journals.

SELECTION CRITERIA

Randomised and quasi-randomised trials of smoking cessation programs implemented during pregnancy.

DATA COLLECTION AND ANALYSIS

Four reviewers assessed trial quality and extracted data independently.

MAIN RESULTS

This review included 64 trials. Fifty-one randomised controlled trials (20,931 women) and six cluster-randomised trials (over 7500 women) provided data on smoking cessation and/or perinatal outcomes. Despite substantial variation in the intensity of the intervention and the extent of reminders and reinforcement through pregnancy, there was an increase in the median intensity of both 'usual care' and interventions over time. There was a significant reduction in smoking in the intervention groups of the 48 trials included: (relative risk (RR) 0.94, 95% confidence interval (CI) 0.93 to 0.95), an absolute difference of six in 100 women continuing to smoke. The 36 trials with validated smoking cessation had a similar reduction (RR 0.94, 95% CI 0.92 to 0.95). Smoking cessation interventions reduced low birthweight (RR 0.81, 95% CI 0.70 to 0.94) and preterm birth (RR 0.84, 95% CI 0.72 to 0.98), and there was a 33 g (95% CI 11 g to 55 g) increase in mean birthweight. There were no statistically significant differences in very low birthweight, stillbirths, perinatal or neonatal mortality but these analyses had very limited power. One intervention strategy, rewards plus social support (two trials), resulted in a significantly greater smoking reduction than other strategies (RR 0.77, 95% CI 0.72 to 0.82). Five trials of smoking relapse prevention (over 800 women) showed no statistically significant reduction in relapse.

REVIEWERS' CONCLUSIONS

Smoking cessation programs in pregnancy reduce the proportion of women who continue to smoke, and reduce low birthweight and preterm birth. The pooled trials have inadequate power to detect reductions in perinatal mortality or very low birthweight.

Cigarette smoking: Evidence to guide measurement

Smoking cessation programs measure outcomes in terms of abstinence from or reduction in smoking. These outcomes can be measured through self-report by the smoker, through measurement with a biological marker of smoking, or through a combination of both. Consideration of the relative advantages of self-report and biomarker approaches is important in the selection of measurement strategies to evaluate outcomes in smoking cessation interventions. In this article both ways of measuring smoking behavior, self-report and biomarkers of carbon monoxide, cotinine, nicotine, thiocyanate, and alkaloids of nicotine, are explored. Measurement approaches are discussed in light of research evidence and their physiologic bases.