Quality of Measurement of Smoking Status by Self-Report and Saliva Cotinine Among Pregnant Women

Objective. The objectives of this paper were to determine the rate of misclassification of smoking and nonsmoking status by self-reports and saliva cotinine of pregnant women participating in a smoking cessation trial, determine the relationship of the number of cigarettes smoked per day and saliva cotinine, and examine whether misclassification was due to an inappropriate saliva cotinine cutoff point. Methods. End of pregnancy self-reports of smoking status and saliva cotinine were used to calculate misclassification rates. Results. The findings revealed that 61 of 441 self-reported smokers had biochemical values inconsistent with smoking status for a smoking misclassification rate of 13.8%. The results also revealed that 28 of 107 self-reported quitters had cotinine values consistent with smoking status for a nonsmoking misclassification rate of 26.2%. Receiver Operating Characteristic (ROC) curves were then plotted to determine whether misclassification resulted from an inappropriate cutoff point. The cotinine cutoff point that maximized sensitivity and specificity for all women was 24 ng/ml. Racial ROC comparisons indicated a higher cutoff point for blacks than whites. Use of any of the ROC indicated cutoff points would not change the misclassification rates. Conclusions. These findings suggest that underreporting of smoking status during pregnancy is high and that social desirability of nonsmoking status may have contributed to the lack of precision in saliva cotinine to distinguish smoking status in this study.     

Prenatal environmental tobacco smoke exposure and early childhood body mass index

Maternal smoking during pregnancy is associated with increased risk of childhood overweight body mass index (BMI). Less is known about the association between prenatal secondhand tobacco smoke (SHS) exposure and childhood BMI. We followed 292 mother-child dyads from early pregnancy to 3 years of age. Prenatal tobacco smoke exposure during pregnancy was quantified using self-report and serum cotinine biomarkers. We used linear mixed models to estimate the association between tobacco smoke exposure and BMI at birth, 4 weeks, and 1, 2 and 3 years. During pregnancy, 15% of women reported SHS exposure and 12% reported active smoking, but 51% of women had cotinine levels consistent with SHS exposure and 10% had cotinine concentrations indicative of active smoking. After adjustment for confounders, children born to active smokers (self-report or serum cotinine) had higher BMI at 2 and 3 years of age, compared with unexposed children. Children born to women with prenatal serum cotinine concentrations indicative of SHS exposure had higher BMI at 2 (mean difference [MD] 0.3 [95% confidence interval -0.1, 0.7]) and 3 (MD 0.4 [0, 0.8]) years compared with unexposed children. Using self-reported prenatal exposure resulted in non-differential exposure misclassification of SHS exposures that attenuated the association between SHS exposure and BMI compared with serum cotinine concentrations. These findings suggest active and secondhand prenatal tobacco smoke exposure may be related to an important public health problem in childhood and later life. In addition, accurate quantification of prenatal secondhand tobacco smoke exposures is essential to obtaining valid estimates.     

Tobacco use and secondhand smoke exposure during pregnancy: an investigative survey of women in 9 developing nations

Objectives. We examined pregnant women''s use of cigarettes and other tobacco products and the exposure of pregnant women and their young children to secondhand smoke (SHS) in 9 nations in Latin America, Asia, and Africa.Methods. Face-to-face surveys were administered to 7961 pregnant women (more than 700 per site) between October 2004 and September 2005.Results. At all Latin American sites, pregnant women commonly reported that they had ever tried cigarette smoking (range: 78.3% [Uruguay] to 35.0% [Guatemala]). The highest levels of current smoking were found in Uruguay (18.3%), Argentina (10.3%), and Brazil (6.1%). Experimentation with smokeless tobacco occurred in the Democratic Republic of the Congo and India; one third of all respondents in Orissa, India, were current smokeless tobacco users. SHS exposure was common: between 91.6% (Pakistan) and 17.1% (Democratic Republic of the Congo) of pregnant women reported that smoking was permitted in their home.Conclusions. Pregnant women''s tobacco use and SHS exposure are current or emerging problems in several low- and middle-income nations, jeopardizing ongoing efforts to improve maternal and child health.Tobacco use is widely recognized as one of the leading threats to global health.¹ Historically, the prevalence of smoking among women in the developing world has been very low, in part because of strong cultural constraints against women''s smoking; approximately 50% of men in developing nations smoke cigarettes, compared with 9% of women.² Averting an increase in the prevalence of smoking among women in developing nations is widely recognized as a significant public health opportunity.^3,4Pregnant women are a priority population for tobacco control efforts because both cigarette smoking and smokeless tobacco use during pregnancy pose serious risks to fetal health. Smoking during pregnancy may cause preterm delivery, low birthweight, and sudden infant death syndrome; smokeless tobacco use during pregnancy has been associated with stillbirth, preterm birth, and reduced birthweight.^5–8 Maternal tobacco use is also likely to expose infants and children to secondhand smoke (SHS) and to provide a role model for children''s use of tobacco. Intervening during pregnancy is also important because of the health risks to the woman, who potentially has many years of remaining life. For cigarette smoking, these health risks include lung and other cancers, coronary heart disease and stroke, and chronic obstructive pulmonary disease; health risks from smokeless tobacco products include oral and pancreatic cancer.^9,10The US National Institute of Child Health and Human Development''s Global Network for Women''s and Children''s Health Research consists of 10 research units chosen for scientific merit that are focused on improving maternal and children''s health in the developing world. To determine whether pregnant women''s tobacco use and SHS exposure are emerging public health issues, the Global Network undertook an investigative survey of pregnant women''s knowledge, attitudes, and behaviors regarding tobacco use and SHS exposure. Here we report findings on pregnant women''s experimentation with and use of tobacco products, their perceptions of the social acceptability of tobacco use by women, and their and their young children''s exposure to SHS.     

Saliva cotinine levels in smokers and nonsmokers

The authors collected by mail self-reported data on smoking habits and saliva samples that were analyzed for cotinine concentration in 222 smokers and 97 nonsmokers. Participants were members of the University of Geneva (Switzerland) in 1995. The 207 cigarette-only smokers smoked on average 10.7 cigarettes/day and had a median concentration of cotinine of 113 ng/ml. The cotinine concentration was moderately associated with the number of cigarettes smoked per day (+14 ng/ml per additional cigarette, p < 0.001, R2 = 0.45) and was 54 ng/ml higher in men than in women after adjustment for cigarettes per day and for the Fagerstr?m Test for Nicotine Dependence. The cotinine level was not associated with the nicotine yield of cigarettes (r= 0.08). In nonsmokers, the median concentration of cotinine was 2.4 ng/ml. The cotinine concentration was 1.5 times higher in nonsmokers whose close friends/spouses were smokers than in nonsmokers whose close friends/spouses were nonsmokers (p = 0.05). A cutoff of 7 ng/ml of cotinine distinguished smokers from nonsmokers with a sensitivity of 92.3% and a specificity of 89.7%; a cutoff of 13 ng/ml provided equally satisfactory results (sensitivity, 86.5%; specificity, 95.9%). This study provides evidence for the construct validity of both questionnaires and saliva cotinine for the assessment of active and passive exposure to tobacco smoke.     

Cotinine in an ultrafiltrate of saliva.

BACKGROUND. We have developed a device for the simplified collection of a prepurified sample of saliva in the mouth. METHOD. The device is based on the principle of an osmotic pump and accumulated about 1.2 ml of an ultrafiltrate of saliva within 8 min. We have investigated the ultrafiltrate for its utility as a biological medium in the evaluation of cigarette smoking status. RESULTS. (a) In 58 matched samples from 13 subjects, the correlation coefficient for the cotinine concentration in the saliva and the ultrafiltrate was 0.95; (b) in matched plasma and ultrafiltrate samples from 27 smokers, the correlation coefficient for the cotinine concentrations was 0.96 with plasma containing 1.2 times the ultrafiltrate mean; (c) in a nonsmoker, elevated cotinine levels could be detected in the ultrafiltrate more than 24 hr after smoking 2 cigarettes, and the pattern of rise and decrease reflected that in whole saliva; and (d) in a habitual smoker; the mean cotinine concentration in the ultrafiltrate was 157 ng/ml (SD +/- 25.7 ng/ml) during a period of smoking 15 cigarettes per day and dropped to a mean of 47 ng/ml (SD +/- 10.5) when smoking was reduced to 5 cigarettes per day; after cessation of smoking, detectable concentrations of cotinine persisted for up to 5 days. CONCLUSION. The device facilitated the aesthetic, noninvasive collection of a biological sample useful in the validation of smoking status.     

Tobacco Exposure,Weight Status,and Elevated Blood Pressure in Adolescents

The pathogenesis of hypertension begins in youth. An estimated 4 % of US adolescents have diagnosed hypertension and 17 % have elevated blood pressures, predisposing them to hypertension and cardiovascular disease (CVD) later in life. There is limited research on the clustering of CVD risk factors such as tobacco exposure and weight status that may be associated with high blood pressure in adolescents. The aim of this exploratory study was to determine the relationships between total smoke exposure (TSE; cigarette smoking and secondhand smoke), waist circumference, and blood pressure in a sample of rural adolescents, ages 15–18. A convenience sample of 148 adolescents ages 15–18 was recruited from two rural high schools (88 female and 60 male, all Caucasian). Adolescents were assessed for tobacco exposure (self-report, salivary cotinine), weight status (body mass index, waist circumference), and blood pressure. Self-report measures of tobacco exposure included the Uptake Continuum and Peer and Family Smoking measure. Age, gender, waist circumference and salivary cotinine contributed to 35 % of the variance in systolic blood pressure and 18 % in diastolic blood pressure. One-fourth (25 %) of adolescent males and 11 % of adolescent females had elevated systolic blood pressures. Approximately one-fifth of the sample (22 %) had elevated salivary cotinine levels indicative of tobacco use and secondhand smoke exposure. TSE and waist circumference were predictors of elevated blood pressure in adolescents. Public health measures need to address clusters of risk factors including blood pressure, tobacco exposure, and weight status among adolescents in order to reduce CVD.     

A review of the use of saliva cotinine as a marker of tobacco smoke exposure

Cotinine, the major metabolite of nicotine, is a useful marker of exposure to tobacco smoke. It can be measured in plasma, urine, or saliva. However, distinguishing between active and passive smoking on the basis of a cotinine measurement may be difficult. In order to evaluate the relationship between saliva cotinine concentration and self-reported tobacco smoke exposure in both active and passive smokers, an English-language literature search using MEDLINE was conducted (1973-1989), and the bibliographies of identified articles were reviewed. Of 43 originally identified articles, only 22 met the criteria for inclusion. Specific information regarding population studied, reported tobacco smoke exposure, method of measurement, and cotinine concentrations was assessed. Passive smokers usually have cotinine concentrations in saliva below 5 ng/ml, but heavy passive exposure can result in levels greater than or equal to 10 ng/ml. Levels between 10 and 100 ng/ml may result from infrequent active smoking or regular active smoking with low nicotine intake. Levels greater than 100 ng/ml are probably the result of regular active smoking. Four categorizations of tobacco smoke exposure are suggested on the basis of saliva cotinine concentrations.     

Fetal Exposure to Secondhand Tobacco Smoke Assessed by Maternal Self-reports and Cord Blood Cotinine: Prospective Cohort Study in Krakow

Objectives While the validity of self-reported smoking habits is generally judged as satisfactory, objective markers of secondhand smoke (SHS) exposure may be more useful in validating the causal links between prenatal SHS and health effects. The cohort study in Krakow provided an opportunity for comparative assessment of fetal exposure to SHS based upon questionnaires and cord blood cotinine measurements. Methods The study sample included 467 newborns born to women recruited in the first and second trimester of pregnancy. To compare the validity of self-reported SHS and cord blood cotinine levels in assessing the association between fetal passive smoking and health effects of newborns, we separately examined the regression coefficients of birthweight on self-reported number of cigarettes smoked by other household members during the entire pregnancy and cord blood cotinine levels. Results In the non-exposed newborns the geometric mean of cord blood cotinine was 0.077 ng/ml and was significantly lower than in newborns with a maternal report of SHS. Cord cotinine levels were more highly correlated with a self-reported number of cigarettes smoked daily at home in the third trimester of pregnancy. The two measures of SHS (number of cigarettes and number of hours of daily exposure) were equally well correlated with cord blood cotinine levels. Using cotinine as the exposure variable, overall the association was not significant; but among the subgroup with cord cotinine levels above the median (≥0.083 ng/ml), the association with birthweight was significant (beta coefficient = −113.65, P = 0.041). Conclusion The study provides evidence that the assessment of fetal SHS exposure based on cord blood cotinine produced better estimates of the association between exposure and birth outcomes. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.     

Prevalence of cigarette smoking in pregnant women participating in the special supplemental nutrition programme for Women,Infants and Children (WIC) in Minneapolis and Saint Paul,Minnesota, USA

Several adverse birth outcomes are associated with cigarette smoking. It is important to determine the prevalence of cigarette smoking among pregnant low-income women and to evaluate their smoking cessation patterns in order to target appropriate interventions. Ethnically diverse pregnant women aged 15-45 years were recruited from Minneapolis or Saint Paul Women, Infants, and Children (WIC) clinics before their third trimester. Serum cotinine levels were assayed for 98 women and compared with self-report. The women were unaware that their smoking status would be validated. Twenty-one (21%) women had a positive serum cotinine value (> or =3 ng/mL); 16 (76%) admitted smoking within the previous 24 h before interview and five denied smoking. Of the five, four had cotinine levels that could suggest passive smoke exposure. Thirty-seven women (38%) admitted cigarette smoking during the pregnancy but before knowing that they were pregnant; 18 (49%) of these denied current smoking at the interview and also presented with negative cotinine levels. These data suggest that some participants in WIC make a concerted effort to quit smoking when they find out they are pregnant, and are generally truthful when reporting their smoking habits during pregnancy.     

The Relationship Between Maternal–Fetal Attachment and Cigarette Smoking Over Pregnancy

Cigarette smoking during pregnancy is one of the most preventable causes of infant morbidity and mortality, yet 80 % of women who smoked prior to pregnancy continue to smoke during pregnancy. Past studies have found that lower maternal–fetal attachment predicts smoking status in pregnancy, yet past research has not examined whether maternal–fetal attachment predicts patterns or quantity of smoking among pregnant smokers. The aim of this study was to examine the relationship between maternal–fetal attachment and patterns of maternal smoking among pregnant smokers. We used self-reported and biochemical markers of cigarette smoking in order to better understand how maternal–fetal attachment relates to the degree of fetal exposure to nicotine. Fifty-eight pregnant smokers participated in the current study. Women completed the Maternal–Fetal Attachment Scale, reported weekly smoking behaviors throughout pregnancy using the Timeline Follow Back interview, and provided a saliva sample at 30 and 35 weeks gestation and 1 day postpartum to measure salivary cotinine concentrations. Lower maternal–fetal attachment scores were associated with higher salivary cotinine at 30 weeks gestation and 1 day postpartum. As well, women who reported lower fetal attachment reported smoking a greater maximum number of cigarettes per day, on average, over pregnancy. Lower maternal–fetal attachment is associated with greater smoking in pregnancy. Future research might explore whether successful smoking cessation programs improve maternal assessments of attachment to their infants.     

Simultaneous measurement of urinary total nicotine and cotinine as biomarkers of active and passive smoking among Japanese individuals

Objectives

Measuring urinary cotinine is a popular and established method of biologically monitoring exposure to tobacco smoke. However, the lower detection limit of cotinine often impedes the evaluation of passive (second-hand) smoking and this, together with unconverted nicotine, does not reflect actual levels of exposure. Furthermore, a portion of the Japanese population might have decreased ability to metabolize nicotine. The present study was therefore carried out to validate the simultaneous analysis of total concentrations of free nicotine and cotinine and their glucuronides to determine actual levels of voluntary and involuntary exposure to cigarette smoke.

Methods

Urine samples from 118 Japanese smokers and 117 non-smokers were analyzed using gas chromatography–mass spectrometry. Voluntary and involuntary smoking status was self-reported and workplace smoking restrictions were objectively evaluated.

Results

The integrated sum of all concentrations showed 2.2- and 2.4-fold higher total levels (free and glucuronide) of nicotine and cotinine relative to the free levels. Median (quartiles) of total nicotine and cotinine were 1635 (2222) and 3948 (3512) ng/mL in smokers, and 3.5 (5.3) and 2.8 (4.2) ng/mL in non-smokers. Concentrations of urinary nicotine were higher than those of cotinine in 21 % of smokers and in 54 % of non-smokers. Nicotine and cotinine levels were significantly associated with a smoking habit, as well as being significantly associated with the workplace and home environments of non-smokers.

Conclusions

The present method can monitor voluntary and involuntary exposure to tobacco smoke. Measuring total urinary nicotine levels might be useful for analyzing exposure to cigarette smoke among non-smokers.     

Self-reported smoking, cotinine levels, and patterns of smoking in pregnancy

Non-pregnant adult smokers generally exhibit fairly stable smoking behaviour over time. In studies of this population, cotinine assays are considered a 'gold standard' measure of exposure to cigarette smoke; current smoking status can be validated with high sensitivity and specificity. In contrast, there is substantial within-person fluctuation in pregnancy smoking, as women try repeatedly to quit or cut down. As a result, cotinine measures may be of limited use for validation of amount smoked, as they are informative only about recent exposure, vary with individual smoking topography and are dependent on time lapsed since the last cigarette smoked. Thus, in reproductive epidemiology, where timing, intensity and duration of exposure are critical, self-reported history of cigarette consumption may be a more relevant fetal exposure than current smoking status. If there were substantial within-person variation over the course of pregnancy, numerous measures of cotinine would be needed to characterise patterns of fetal exposure and would not be feasible in many studies. We examined self-reported smoking patterns and compared them to patterns of urinary cotinine levels in a prospective study of 998 pregnant women, recruited 1988-92. Fluctuations in smoking were considerable and, while cotinine measures and self-reported number of cigarettes were highly correlated at any given time point across women (r=0.70), the within-person correlation between the patterns of self-reported number of cigarettes and cotinine levels was weaker (r=0.33). For researchers interested in fetal outcomes in which intensity and timing of exposure are critical, we conclude that self-reported variations in smoking during pregnancy may be a valid way to characterise detailed patterns of fetal exposure in epidemiological studies.     

Prenatal Cigarette Smoking and Smokeless Tobacco Use Among Alaska Native and White Women in Alaska, 1996–2003

Objective To examine trends in prenatal cigarette smoking and smokeless tobacco use among Alaska Native (AN) and white women in Alaska. Methods Using 1996–2003 data from the population-based Pregnancy Risk Assessment Monitoring System, we determined trends in self-reported prenatal tobacco use among AN and white women and used chi-square tests and multiple variable logistic regression analysis to identify maternal factors associated with prenatal tobacco use. Results Over the study period, prevalence of any tobacco use during pregnancy declined by 27% among AN women (from 55.8 to 40.9%) (P < 0.0001) and by 17% among white women (from 18.8 to 15.6%) (P < 0.0001). In 2003, among AN women the prevalence of self-reported smokeless tobacco use was 16.9%, cigarette smoking was 25.7%, and any tobacco use was 40.9%; corresponding values for white women were 0.4, 15.0, and 15.6%, respectively. Western Alaska had the highest prevalence of tobacco use. Conclusion The prevalence of tobacco use decreased between 1996 and 2003, but remained higher among AN women than white women, especially for smokeless tobacco. Support for cessation interventions targeting pregnant women should be made a public health priority in Alaska. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.     

Reduced secondhand smoke exposure after implementation of a comprehensive statewide smoking ban--New York, June 26, 2003-June 30, 2004

dSecondhand smoke (SHS) causes premature disease and death in nonsmokers, including heart disease and lung cancer. The Surgeon General has concluded that no risk-free level of SHS exposure exists; the only way to fully protect nonsmokers is to completely eliminate smoking in indoor spaces. Studies have determined that levels of airborne particulate matter in restaurants, bars, and other hospitality venues and levels of SHS exposure among nonsmoking hospitality employees decrease substantially and rapidly after implementation of laws that prohibit smoking in indoor workplaces and public places. To assess changes in indoor SHS exposure in a general population, the New York State Department of Health analyzed data on observations of indoor smoking by respondents to the New York Adult Tobacco Survey (NYATS) and measured levels of cotinine in saliva among nonsmoking NYATS respondents before and after implementation of the 2003 New York state ban on smoking in indoor workplaces and public places. This report describes the results of that analysis, which determined that reports of indoor smoking among restaurant and bar patrons decreased significantly after the law took effect; moreover, saliva cotinine levels in nonsmoking NYATS participants decreased by 47.4% over the same period. These findings suggest that comprehensive smoking bans can reduce SHS exposure among nonsmokers.     

Sexual Orientation–Related Differences in Tobacco Use and Secondhand Smoke Exposure Among US Adults Aged 20 to 59 Years: 2003–2010 National Health and Nutrition Examination Surveys

Objectives. We investigated sexual orientation–related differences in tobacco use and secondhand smoke (SHS) exposure in a nationally representative sample of US adults.Methods. The 2003–2010 National Health and Nutrition Examination Surveys assessed 11 744 individuals aged 20 to 59 years for sexual orientation, tobacco use, and SHS exposure (cotinine levels ≥ 0.05 ng/mL in a nonsmoker). We used multivariate methods to compare tobacco use prevalence and SHS exposure among gay or lesbian (n = 180), bisexual (n = 273), homosexually experienced (n = 388), and exclusively heterosexual (n = 10 903) individuals, with adjustment for demographic confounding.Results. Lesbian and bisexual women evidenced higher rates of tobacco use than heterosexual women. Among nonsmokers, SHS exposure was more prevalent among lesbian and homosexually experienced women than among heterosexual women. Nonsmoking lesbians reported greater workplace exposure and bisexual women greater household exposure than heterosexual women did. Identical comparisons among men were not significant except for lower workplace exposure among nonsmoking gay men than among heterosexual men.Conclusions. Nonsmoking sexual-minority women are more likely to be exposed to SHS than nonsmoking heterosexual women. Public health efforts to reduce SHS exposure in this vulnerable population are needed.In 2006, the US Surgeon General1 concluded that secondhand smoke (SHS) exposure causes premature death and disease in nonsmoking persons2,3 and that there is no risk-free level of exposure.4 Although public health efforts to lower the rates of cigarette smoking have been generally successful over the years, cigarette smoking nevertheless remains one of the leading causes of death.5 Among nonsmokers, minority sexual orientation (i.e., lesbian, gay, bisexual, and homosexually experienced status) may be an unrecognized risk indicator for SHS exposure. Sexual minority individuals are more likely, as a group, to smoke tobacco than heterosexual men and women are.6–20 Indeed, estimates indicate that smoking rates may be twice as high among persons with a minority sexual orientation than among heterosexual individuals.21 Women with minority sexual orientation, in particular, consistently show elevation in risk compared with their same-gender heterosexual counterparts.10,13,22,23 Overall, this greater prevalence of tobacco use among friends and relationship partners of sexual minorities may inadvertently lead to higher levels of SHS exposure among nonsmoking sexual minorities.Although there is evidence that sexual minorities share similar levels of concern as heterosexuals do about the risk of SHS exposure,21 whether SHS exposure is nonetheless greater in this subpopulation is currently unknown, though there is reasoned suspicion that this might be so.24 We investigated possible sexual orientation–related differences in prevalence of primary tobacco use and SHS exposure by using information available from the 2003–2010 National Health and Nutrition Examination Surveys (NHANES). During these years, the NHANES assessed both respondents’ sexual orientation status and markers of tobacco use and SHS exposure. Consistent with previous studies, we hypothesized that individuals with minority sexual orientation, especially women, will show elevated tobacco use compared with their same-gender heterosexual counterparts. However, we also anticipated that, among nonsmokers, evidence of secondhand exposure to tobacco would be positively associated with minority sexual orientation.     

Maternal tobacco smoke exposure and persistent pulmonary hypertension of the newborn.

We propose that in utero exposure to tobacco smoke products places a newborn at risk for persistent pulmonary hypertension of the newborn (PPHN). To test this hypothesis, infants with PPHN were identified. Healthy newborns of similar ethnicity were identified as a comparison group. Cord blood cotinine concentrations and maternal questionnaires were obtained. The number of women exposed to tobacco smoke in each group ascertained by questionnaire was borderline significantly different (38.7% vs. 20.5%; p = 0.080). However, more PPHN infants had detectable cotinine in their cord blood (64.5% vs. 28.2%; p = 0.002), and the median cotinine concentrations were significantly higher (5.2 ng/ml vs. 2 ng/ml; p = 0.051) than the comparison infants. Among infants delivered to nonsmoking women, more PPHN infants had detectable cotinine (50% vs. 19%; p = 0.015), and the cotinine concentrations were higher (3.5 ng/ml vs. 1.65 ng/ml; p = 0.022) than the comparison group. We conclude that active and passive smoking during pregnancy is a risk factor for PPHN. Therefore, we recommend that pregnant women cease smoking and avoid environmental tobacco smoke. Key words. cotinine, newborns, passive, persistent pulmonary hypertension, smoking, tobacco smoke pollution.     

被动吸烟的孕妇体内生物标志物的检测与分析

目的通过检测被动吸烟的孕妇体内生物标志物,研究被动吸烟对孕妇及胎儿健康的影响。方法采用自制问卷,由236个孕妇自填问卷的形式,进行被动吸烟相关信息的问卷调查,调查同时收集孕妇唾液、静脉血、尿和脐带血,将所调查的236名孕妇按被动吸烟量分为无被动吸烟、被动吸烟量<10支/d、10支/d≤被动吸烟量<20支/d和被动吸烟量≥20支/d共4个组,用吡啶-巴比妥酸法测定唾液硫氰酸盐含量,用巴比妥酸比色法测定孕妇静脉血、尿及脐带血可铁宁含量。结果不同被动吸烟量各组孕妇唾液硫氰酸盐含量差异有统计学意义,随着被动吸烟量的增加,唾液中硫氰酸盐含量升高;各组间静脉血、尿、脐带血可铁宁含量差异分别亦有统计学意义,随着被动吸烟量的增加,静脉血、尿、脐带血可铁宁含量升高。结论静脉血、尿、脐带血可铁宁含量是孕妇被动吸烟的体内生物标志物,孕妇被动吸烟可对自身及胎儿的健康产生影响。     

Tobacco Smoke Exposure and Serum Cotinine in a Random Sample of Adults Living in Verona,Italy

In this study, the authors attempted to validate answers to smoking-habit questions contained in the European Community Respiratory Health Survey questionnaire. The respondents were invited to visit the chest clinic at Verona, Italy, and their serum cotinine levels were measured. The authors invited each of 504 subjects to complete a respiratory interview and to give a blood sample for a radioimmunoassay serum cotinine measurement. A total of 375 subjects responded, of whom 129 were smokers (34.4%), 79 were exsmokers (21.1%), and 167 (44.5%) had never smoked. Exposure to environmental tobacco smoke was reported by 216 subjects (57.6% [mean exposure = 3.8 hr/day {± 3.4 hr/day standard deviation}]). In smokers, serum cotinine levels were directly related to the number of cigarettes smoked/day. The authors excluded from analysis nonsmokers who had serum cotinine levels that were ≥ 14 ng/ml, and the resulting mean values were 1.7 ng/ml (± 2.1 ng/ml standard deviation) in nonsmokers unexposed to environmental tobacco smoke and 2.6 ng/ml (± 2.6 ng/ml standard deviation) (p < .002) in nonsmokers exposed to environmental tobacco smoke. There was a relationship between serum cotinine levels and hours of exposure to environmental tobacco smoke (R ² = .136, p < .05). Serum cotinine, which is an objective and accepted measure of tobacco exposure, confirmed the validity of the European Community Respiratory Health Survey questionnaire with respect to smoking habits and environmental tobacco smoke exposure.     

Bar workers' exposure to second-hand smoke: the effect of Scottish smoke-free legislation on occupational exposure

OBJECTIVES: To examine changes in bar workers' exposure to second-hand smoke (SHS) over a 12-month period before and after the introduction of Scottish smoke-free legislation on the 26 March 2006. METHODS: A total of 371 bar workers were recruited from 72 bars in three cities: Aberdeen, Glasgow, Edinburgh and small towns in two rural regions (Borders and Aberdeenshire). Prior to the introduction of the smoke-free legislation, we visited all participants in their place of work and collected saliva samples, for the measurement of cotinine, together with details on work patterns, self-reported exposure to SHS at work and non-work settings and smoking history. This was repeated 2 months post-legislation and again in the spring of 2007. In addition, we gathered full-shift personal exposure data from a small number of Aberdeen bar workers using a personal aerosol monitor for fine particulate matter (PM(2.5)) at the baseline and 2 months post-legislation visits. RESULTS: Data were available for 371 participants at baseline, 266 (72%) at 2 months post-legislation and 191 (51%) at the 1-year follow-up. The salivary cotinine level recorded in non-smokers fell from a geometric mean of 2.94 ng ml(-1) prior to introduction of the legislation to 0.41 ng ml(-1) at 1-year follow-up. Paired data showed a reduction in non-smokers' cotinine levels of 89% [95% confidence interval (CI) 85-92%]. For the whole cohort, the duration of workplace exposure to SHS within the last 7 days fell from 28.5 to 0.83 h, though some bar workers continued to report substantial SHS exposures at work despite the legislation. Smokers also demonstrated reductions in their salivary cotinine levels of 12% (95% CI 3-20%). This may reflect both the reduction in SHS exposure at work and falls in active cigarette smoking in this group. In a small sub-sample of bar workers, full-shift personal exposure to PM(2.5), a marker of SHS concentrations, showed average reductions of 86% between baseline and 2 months after implementation of the legislation. CONCLUSIONS: Most bar workers have experienced very large reductions in their workplace exposure to SHS as a result of smoke-free legislation in Scotland. These reductions have been sustained over a period of 1 year.