Secondhand Smoke Exposure Status Research Articles

Tobacco Smoke Is a Major Source of Aromatic Amine Exposure in U.S. Adults: 2013-2014 National Health and Nutrition Examination Survey (NHANES).

Cigarette smoking increases the risk of cancer, cardiovascular diseases, and premature death. Aromatic amines (AA) are found in cigarette smoke and are well-established human bladder carcinogens. We measured and compared total urinary levels of 1-aminonaphthalene (1AMN), 2-aminonaphthalene (2AMN), and 4-aminobiphenyl (4ABP) in adults who smoked cigarettes exclusively and in adult nonusers of tobacco products from a nationally representative sample of non-institutionalized U.S. population in the 2013-2014 National Health and Nutrition Examination Survey. Sample-weighted geometric mean concentrations of AAs in adults who smoked cigarettes exclusively compared with adult nonusers were 30 times higher for 1AMN and 4 to 6 times higher for 2AMN and 4ABP. We evaluated the association of tobacco-smoke exposure with urinary AAs using sample-weighted multiple linear regression models to control for age, sex, race/ethnicity, diet, and urinary creatinine. Secondhand smoke exposure status was categorized using serum cotinine (SCOT) among adult nonusers (SCOT ≤ 10 ng/mL). The exposure for adults who smoked cigarettes exclusively (SCOT > 10 ng/mL) was categorized on the basis of the average number of self-reported cigarettes smoked per day (CPD) in the five days prior to urine collection. The regression models show AAs concentration increased with increasing CPD (P < 0.001). Dietary-intake variables derived from the 24-hours recall questionnaire were not consistently significant predictors of urinary AAs. This is the first characterized total urinary AA concentrations of the U.S. adult non-institutionalized population. Our analyses show that smoking status is a major contributor to AA exposures. These data provide a crucial baseline for exposure to three AAs in U.S. non-institutionalized adults.

Relationship between childhood secondhand smoke exposure and the occurrence of hyperlipidaemia and coronary heart disease among Chinese non-smoking women: a cross-sectional study

ObjectiveThe objective of this study was to evaluate the influence of secondhand smoke (SHS) exposure during childhood on type 2 diabetes mellitus, hypertension, hyperlipidaemia and coronary heart disease among Chinese...

Association between secondhand smoke exposure and new-onset hypertension in self-reported never smokers verified by cotinine.

Background/AimsThere is no study assessing the effect of changes of secondhand smoke (SHS) exposure and new-onset hypertension. We investigated the effect of a change of SHS exposure status on new-onset hypertension in self-reported and cotinine-verified never smokers.MethodsOut of individuals enrolled in the Kangbuk Samsung Health Study between 2011 and 2016, 87,486 self-reported and cotinine-verified never smokers without hypertension at baseline visit were included with a median follow-up of 36 months. Individuals were divided into four groups on the basis of their SHS exposure status at baseline and at follow-up: no, new, former, and sustained SHS exposure groups.ResultsThe incidence rates per 10,000 person-year of new-onset hypertension in no, new, former, and sustained SHS exposure groups were 84.7, 113.3, 102.0, and 123.7, respectively (p < 0.001). A multivariable Cox-hazard analyses showed that new and sustained SHS exposure groups increased their hazard ratio (HR) for new-onset hypertension compared to no SHS exposure group (HR, 1.31; 95% confidence interval [CI], 1.08 to 1.60 for new SHS exposure group; and HR, 1.24; 95% CI, 1.06 to 1.45 for sustained SHS exposure group). However, being part of the former SHS exposure group did not increase the risk of new-onset hypertension (HR, 0.91; 95% CI, 0.81 to 1.03).ConclusionsThis study showed that either new, or sustained SHS exposure, but not former SHS exposure, increased the risk for new-onset hypertension in self-reported never smokers verified as nonsmokers by urinary cotinine. These findings show the possibility that changing exposure to SHS even for a relatively short period can modify the risk of new-onset hypertension in self-reported and cotinine-verified never smokers.

Evaluation of tobacco screening and counseling in a large, midwestern pediatric emergency department.

INTRODUCTIONThe study objective was to assess tobacco screening and cessation counseling practices of pediatric emergency department (PED) and urgent care (UC) nurses and physicians, and factors associated with these practices. Secondarily, we assessed factors associated with performing tobacco smoke exposure reduction and tobacco cessation counseling.METHODSWe conducted a cross-sectional survey of 30 PED/UC nurses and physicians working at one large, urban, Midwestern children’s hospital. Measures included current practices of performing the 5 As of tobacco counseling (Ask, Advise, Assess, Assist, Arrange), and attitude and practice factors that may influence practices.RESULTSOverall, 90.0% of participants had not received recent tobacco counseling training, 73.3% were unaware of the 5 As, and 63.3% did not have a standardized, routine screening system to identify patients exposed to secondhand smoke. The majority of participants reported that they: asked about patients’ secondhand smoke exposure status (70.0%) and parents’ tobacco use status (53.3%), and advised parental smokers to not smoke around their child (70.0%) and to quit smoking (50%). One in five participants reported they assessed smokers’ interest in quitting smoking, and 16.7% talked with smokers about cessation techniques and tactics; of these, 10% referred/enrolled smokers to the Tobacco Quitline or cessation program, and 6.7% made a quit plan or recommended nicotine replacement therapy medication.CONCLUSIONSKey findings identified are the need for professional tobacco counseling training, standardizing efforts during visits, and emphasizing pediatric patients’ potential health benefits. This information will be used for developing a PED/ UC-based parental tobacco cessation and child tobacco smoke exposure reduction intervention.

Association between secondhand smoke exposure and new-onset hypertension in 65169 self-reported never smokers verified by cotinine

Abstract Background No study has reported the relationship between secondhand smoke (SHS) exposure and new-onset hypertension (NOHT) in self-reported never-smokers verified by cotinine. Purpose This longitudinal study was conducted to evaluate whether the change of SHS exposure status at baseline and at follow-up affects NOHT in self-reported and cotinine-verified never-smokers. Methods Out of individuals enrolled in the Kangbuk Samsung Cohort study (KSCS) between 2012 and 2016, 65,169 self-reported and cotinine-verified never-smokers without hypertension at baseline visit (20,046 men; age 36±5.7 years) were included. The mean follow-up period in this study was 32 months (6–58 months). SHS exposure was defined as having experienced passive smoking indoors at home or the workplace. Individuals were divided into 4 groups on the basis of their SHS exposure status at baseline and at follow-up: no SHS exposure group (Group I) as individuals without SHS exposure both at baseline and at follow-up; new SHS exposure group (Group II) as those without SHS exposure at baseline and with SHS exposure at follow-up; ex-SHS exposure group (Group III) as those with SHS exposure at baseline and without SHS exposure at follow-up; continuous SHS exposure group (Group IV) as those with SHS exposure both at baseline and at follow-up. New-onset hypertension was defined as systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg, or current use of antihypertensive medication(s) at follow-up. Results The incidence of NOHT in the overall population was 2.5%; the incidence in group I, II, III, and IV was 2.3%, 3.2%, 2.9%, and 3.1%, respectively (p&amp;lt;0.001). The results in a multivariate Cox-hazard model adjusted for the baseline variables including age, sex, body mass index, waist circumference, vigorous exercise, alcohol consumption and presence of diabetes showed that Group II and IV increased relative risks (RRs) for NOHT compared to Group I (RR[95% CI], 1.44 [1.17, 1.77] for Group II and 1.21 [1.01, 1.45] for Group IV) However, Group III did not increase the risk of NOHT (0.95 [0.83, 1.08]). In another model adjusted for the variables in the above model and creatinine, uric acid, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides and high-sensitivity C reactive protein showed that only Group II increased the risk for NOHT (1.43 [1.16, 1.77] in Group II, 0.94 [0.82, 1.07] in Group III, 1.18 [0.98, 1.41] in Group IV). Conclusions This study showed that the new and continuous SHS exposure, but not ex-SHS exposure, increased the risk for NOHT in self-reported never-smokers verified as nonsmokers by urinary cotinine. In particular, the relationship to increased risk for NOHT was more obvious in individuals with new SHS exposure than in those with continuous SHS exposure. These findings suggest that it is important to continuously minimize SHS exposure and prohibit smoking at home and at workplace to reduce the risk of developing hypertension. Funding Acknowledgement Type of funding source: None

Exposure to Secondhand Smoke in Children is Associated with a Thinner Retinal Nerve Fiber Layer: The Hong Kong Children Eye Study

We sought to assess the effects of exposure to secondhand smoke (SHS) on peripapillary retinal nerve fiber layer (p-RNFL) thickness in children. Cross-sectional study. Children 6-8 years of age were consecutively recruited from the population-based Hong Kong Children Eye Study. All participants received comprehensive ophthalmic examinations and p-RNFL thickness was measured by spectral-domain optical coherence tomography. SHS data were derived from a validated questionnaire. Associations between p-RNFL thickness and SHS exposure status, number of smokers in the family, and quantity of smoking in the family were determined by multivariate linear regression after adjusting for potential confounders. Among the Hong Kong Children Eye Study cohort (n= 3,103), approximately one-third of children were exposed to SHS (35.4%, n= 1,097). Compared to those without exposure to SHS, children exposed to SHS had similar age (P= .83), gender (P= .17), body mass index (P= .44), birth weight (P= .23), and axial length (P= .34), but had lower family income (P < .001) and lower parental education level (P < .001). After adjusting for all the above factors, exposure to SHS was associated with a thinner global p-RNFL by 4.4μm (P < .001). Reduced p-RNFL was also associated with increased numbers of smokers in the family (β=-3.40, P < .001) and increased quantity of SHS (β=-0.22, P < .001). Exposure to SHS in children was associated with a thinner p-RNFL. A thinner p-RNFL may increase the risk of irreversible visual impairment in the future. Our results provide evidence to recommend that children avoid exposure to SHS.

Metabolomics profiling of tobacco exposure in children with cystic fibrosis

BackgroundInflammation is integral to early disease progression in children with CF. The effect of modifiable environmental factors on infection and inflammation in persons with CF is poorly understood. Our prior studies determined that secondhand smoke exposure (SHSe) is highly prevalent in young children with CF. SHSe is associated with increased inflammation, heightened bacterial burden, and worsened clinical outcomes. However, the specific metabolite and signaling pathways that regulate responses to SHSe in CF are relatively unknown. MethodsHigh-resolution metabolomics was performed on plasma samples from infants (n = 25) and children (n = 40) with CF compared to non-CF controls (n = 15). CF groups were stratified according to infant or child age and SHSe status. ResultsGlobal metabolomic profiles segregated by age and SHSe status. SHSe in CF was associated with changes in pathways related to steroid biosynthesis, fatty acid metabolism, cysteine metabolism, and oxidative stress. CF infants with SHSe demonstrated enrichment for altered metabolite localization to the small intestine, liver, and striatum. CF children with SHSe demonstrated metabolite enrichment for organs/tissues associated with oxidative stress including mitochondria, peroxisomes, and the endoplasmic reticulum. In a confirmatory analysis, SHSe was associated with changes in biomarkers of oxidative stress and cellular adhesion including MMP-9, MPO, and ICAM-1. ConclusionsSHSe in young children and infants with CF is associated with altered global metabolomics profiles and specific biochemical pathways, including enhanced oxidative stress. SHSe remains an important but understudied modifiable variable in early CF disease.

Sociodemographic Differences in Secondhand Smoke Exposure in the United States.

Background. Socioeconomic disparities in secondhand smoke (SHS) exposure exist among nonsmokers. The present study examined the prevalence and socioeconomic disparities of both objective and self-reported measures of SHS exposure in various indoor environments among U.S. nonsmokers. Method. Data were drawn from the 2013-2014 and 2015-2016 National Health and Nutrition Examination Survey. The prevalence of objective measures of SHS (nonsmokers with serum cotinine levels of 0.05-10 ng/mL) and the self-reported SHS exposure status in restaurants, cars, and homes other than their own were examined for the overall population as well as by sociodemographic characteristics. Multivariable logistic regression analyses were used to assess the association between sociodemographic characteristics and SHS exposure measures. Results. The prevalence of self-reported SHS exposure in restaurants, cars, and homes other than one's own decreased significantly between 2013-2014 and 2015-2016. We found higher odds of the objective measure of SHS exposure among non-Hispanic Blacks (aOR 2.07, 95% confidence interval [1.93, 2.81]) and males (aOR 1.12, confidence interval [1.05, 1.18]), while lower odds were found among Mexican Americans, other Hispanics, and those who had family income greater or equal to the poverty level. Compared to non-Hispanic Whites, the non-Hispanic Black group had higher odds of SHS exposure in restaurants and homes other than their own. Age was positively associated with self-reported SHS exposure measures but not the objective SHS measure. However, age was negatively associated with SHS measures in the adult sample (aged ≥ 20 years). Conclusions. Findings suggest that although SHS exposure may be decreasing in specific at-risk populations, socioeconomic disparities still exist.

Association between secondhand smoke exposure and abnormal cervical cytology: A one-to-one matched case-control study.

INTRODUCTIONThe aim was to evaluate the association between secondhand smoke (SHS) exposure and abnormal cervical cytology among Chinese adult women.METHODSA one-to-one matched case-control study was conducted with outpatients of the First Hospital of Jilin University between October 2013 to September 2016. In all, 228 cytologic confirmed new cases of abnormal cervical cytology and the equivalent number of age and ethnic matched controls were interviewed about SHS exposure and related factors.RESULTSAlthough 78.3% of all the participants had been exposed to SHS (78.1% subjects vs 78.5% controls), there were no statistical significance of cervical cytological abnormalities and SHS exposure status (never, former, current exposure), exposure intensity in cigarettes per day (none, 1–9, 10–19, and ≥20), SHS exposure duration in years (none, 1–9, 10–19, and ≥20) and the Brinkman Index (BI) (none, 1–99, 100–399, ≥400) between the two groups. The univariate analysis results showed that there were statistical differences between subjects and controls in marital status, sexual frequency in past year, number of sexual partners, age at first intercourse, age at first delivery. The stratified Cox regression model only showed that the age at first sexual intercourse was associated with the cervical cytological abnormalities (OR=1.206, 95% CI: 1.104–1.319).CONCLUSIONSStudies on the association between SHS exposure and cervical lesions have been equivocal. In this study, the SHS exposure could not be detected as an independent risk factor of abnormal cervical cytology among Chinese adult women.

Effect of exposure to second-hand smoke from husbands on biochemical hyperandrogenism, metabolic syndrome and conception rates in women with polycystic ovary syndrome undergoing ovulation induction.

Does second-hand smoke (SHS) exposure from husbands have adverse effects on sex hormones, metabolic profiles, clinical phenotypes and fertility outcomes in women with polycystic ovary syndrome (PCOS) undergoing ovulation induction? SHS exposure is associated with worsened biochemical hyperandrogenism, higher incidence of metabolic syndrome and reduced conception rates in women with PCOS. Smoking in women impairs fecundity at some stages of the reproductive process including folliculogenesis, embryo transport, endometrial angiogenesis and uterine blood flow. Yet little is known about the hazard of SHS exposure in women with PCOS. This study was a secondary analysis of the Polycystic Ovary Syndrome Acupuncture and Clomiphene Trial (PCOSAct), a large randomized controlled trial conducted at 27 hospitals from 2012 to 2015 in mainland China. Out of 1000 women with PCOS, SHS exposure status were available in 500 women, of whom 271 women were non-exposed and 229 exposed to cigarette smoke (170 women ≤10 cigarettes per day as low-SHS exposed and 59 women >10 cigarettes per day as high-SHS exposed). We compared circulating sex steroids, glucose and lipid metabolism, metabolic syndrome and phenotypes, fertility and obstetric outcomes between non-exposed and exposed women. Women exposed to SHS, compared to non-exposed women, had a higher serum total testosterone (1.7 vs 1.5 nmol/L, P = 0.01), free androgen index (5.7 vs 4.0, P = 0.001) and lower sex hormone binding globulin (30.1 vs 35.6 nmol/L, P = 0.03). Metabolic syndrome, but not other phenotypes, was more frequent in exposed women as compared to non-exposed women (21.8 vs 13.3%, adjusted odds ratio (OR)=1.66; 95% CI, 1.02-2.71, P = 0.04). Ovulation rates between exposed and non-exposed groups were not significantly different (76.9 vs 82.9%, adjusted OR=0.72; 95% CI, 0.45-1.15, P = 0.17). Conception rates were significant lower in the exposed group (26.6 vs 36.9%; adjusted OR=0.61; 95% CI, 0.41-0.91; P = 0.01), while clinical pregnancy and live birth rates showed a similar trend that was not statistically significant. Gestational age, birth weight and other obstetric outcomes were not affected by SHS exposure. Data on SHS exposure were missing in 50% of the women. We did not assay serum nicotine or cotinine levels to quantify the SHS exposure status. These data suggest that smoking partners of infertile women with PCOS who seek treatment should be advised to quit smoking. Funding was provided by the National Public Welfare Projects for Chinese Medicine (201107005 and 200807002) and the National Clinical Trial Base in Chinese Medicine Special Projects (JDZX2012036 and 2015B009). There are no conflicts of interest. ClinicalTrial.gov number: NCT01573858 and chictr.org.cn number: ChiCTR-TRC-12002081.

Effects of tobacco exposure on perinatal suicidal ideation, depression, and anxiety.

BackgroundPrevious studies have stressed the importance of tobacco exposure for the mood disorders of depression and anxiety. Although a few studies have focused on perinatal women, none have specifically considered the effects of smoking and secondhand smoke exposure on perinatal suicidal ideation. Thus, this study aimed to investigate the relationships of smoking/secondhand smoke exposure status with suicidal ideation, depression, and anxiety from the first trimester to the first month post partum.MethodsThis cross-sectional study based on self-reported data was conducted at five hospitals in Taipei, Taiwan from July 2011 to June 2014. The questionnaire inquired about women’s pregnancy history, sociodemographic information, and pre-pregnancy smoking and secondhand smoke exposure status, and assessed their suicidal ideation, depression, and anxiety symptoms. Logistic regression models were used for analysis.ResultsIn the 3867 women in the study, secondhand smoke exposure was positively associated with perinatal depression and suicidal ideation. Compared with women without perinatal secondhand smoke exposure, women exposed to secondhand smoke independently exhibited higher risks for suicidal ideation during the second trimester (odds ratio (OR) = 7.63; 95 % confidence interval (CI) = 3.25–17.93) and third trimester (OR = 4.03; 95 % CI = 1.76–9.23). Women exposed to secondhand smoke had an increased risk of depression, especially those aged 26–35 years (OR = 1.71; 95 % CI = 1.27–2.29).ConclusionsSecondhand smoke exposure also considerably contributes to adverse mental health for women in perinatal periods, especially for the severe outcome of suicidal ideation. Our results strongly support the importance of propagating smoke-free environments to protect the health of perinatal women.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-016-3254-z) contains supplementary material, which is available to authorized users.

Association between secondhand smoke exposure at home and cigarette gifting and sharing in Zhejiang, China: a repeat cross-sectional study

ObjectivesThe aims of the current study were to assess the prevalence of household cigarette gifting and sharing, and to evaluate the relationship between secondhand smoke (SHS) exposure, and cigarette gifting...

Tobacco Use and Exposure to Second-Hand Smoke among Urban Residents: A Community-Based Investigation.

Objectives: In 2005, China acceded to the World Health Organization Framework Convention on Tobacco Control (WHO FCTC), the foundation for the global fight against tobacco. Certain cities in China have established local regulations to control tobacco use ahead of national policy; however, without the enforcement of statutory law, some of these regulations are merely lip service. The aim of the study was to assess the effects of city policy on smoking prevalence and on second-hand smoke (SHS) exposure status among non-smokers in Changchun City. Methods: A cross-sectional survey covering a multiple-stage, representative sample of the urban population aged ≥15 years was conducted between 1 Dec 2013 and 31 Jan 2014. The WHO and the US Centers for Disease Control and Prevention developed the questionnaires used, which included demographic characteristics, smoking behaviors and SHS exposure status. Results: Overall cigarette smoking prevalence was 23.5%; daily cigarette smoking prevalence was 21.2%. Smoking prevalence and cigarettes consumed per day was higher among men (p < 0.05) and those aged 45–64 years (p < 0.05). Among current smokers, 8.1% planned to quit within 12 months; 53.4% had no intention of quitting. Overall SHS exposure prevalence was 41.9% (workplace) and 34.1% (at home) over the previous 30 days. The weighted workplace SHS exposure prevalence increased with age. Conclusions: The high proportion of smokers with no intention of quitting and the high level of SHS exposure may constitute one of the most significant barriers to successful smoking cessation in the city. A continued drive to promote full implementation of the WHO FCTC is still needed.

Association of Autism Spectrum Disorders with Secondhand Smoke Exposure

Objectives: Second Hand Smoke (SHS) exposure has been associated with neurobehavioral disorders among children. Our objective was to evaluate relationship between SHS and Autism Spectrum Disorders (ASD) in children in the United States (US) and to assess sex distribution of ASD when exposed to SHS. Methods: Parent-reported postnatal SHS exposure inside and outside the house and ASD was examined in children younger than 12 years using the 2011-2012 National Survey on Children's Health. The physician diagnosis of current ASD as reported by the parents was used as the outcome variable. Multiple logistic regression models adjusted for potential confounders and complex survey designs were used to assess associations. Results: Of the 61,076 children (equivalent to weighted 49 million children), 20% had SHS exposure, and 4% were exposed to SHS inside the house, corresponding to a weighted 10 million and 2 million children, respectively. For all children irrespective of SHS exposure status, ASD weighted prevalence and 95% confidence interval was 1.81% (1.56, 2.05) equivalent to 1 in 55 children. Weighted prevalence of ASD in children exposed to SHS outside the house was 2.26% (1.64, 2.87), and 2.57% (1.26, 3.88) with SHS inside the house, compared to 1.67% (1.39, 1.93) in those without SHS exposure (p&lt;0.01). Girls constituted 48% of the total sample. Girls exposed to SHS had 21% higher risk of age adjusted ASD compared to unexposed girls (OR=1.21, 95% CI: 1.01, 1.44, p=0.038). With covariate adjustment, girls had 22% higher risk of ASD when exposed to SHS in comparison to unexposed girls (OR=1.22, 95% CI: 1.02, 1.46, p=0.034). In addition, increasing age of the child, unstable family structure (step or single parent) and mother's age were significantly related to ASD in girls. In boys, increasing age was the only variable significantly associated with ASD and no relationship with SHS was noted. Conclusions: US girls experience a higher prevalence of SHS related ASD.

The independent effects of second hand smoke exposure and maternal body mass index on the anthropometric measurements of the newborn

BackgroundExposure to tobacco smoke during pregnancy, whether as active smoking or by exposure to secondhand smoke (SHS), is associated with adverse pregnancy outcomes including low birth weight (LBW) and small for gestational age infants due to the effect of tobacco on the anthropometric measurements of the newborn. This effect might be masked by maternal obesity as it increases fetal weight. The objectives of this study were to estimate the independent effects of maternal exposure to SHS and maternal body mass index (BMI) on the anthropometric measurements and on the prevalence of macrosomia and LBW among term infants.MethodsData were collected from women in the postnatal ward following delivery. Participants were stratified into six groups based on the BMI (underweight <18 kg/m2, non-obese 18–29.9 kg/m2, and obese ≥30 kg/m2) and the SHS exposure status (exposed and non- exposed), to examine the independent effects of BMI and SHS on infants’ anthropometry. Multiple regression analysis was used to explore the independent associations between the six groups and the risk of delivering a macrosomic or LBW infant.ResultsInfants of women exposed to SHS had significantly reduced anthropometric measurements compared to infants of unexposed women. The odds of delivering a macrosomic baby increased to 9-fold for women with BMI of ≥30 kg/m2 compared to non-obese women; odds ratio (OR) 9.18, 95% Confidence Interval (CI) (1.01, 9.37); p = 0.04, this risk was attenuated to 1.5-fold in women exposed to SHS, OR 1.53, 95% CI (1.19, 12.1); p < 0.0001. The odds of delivering an LBW infant were more than doubled in underweight women compared to non-obese women, OR 2.15, 95% CI (1.001, 4.57); p = 0.034, and were further increased to almost 3-fold for women who were exposed to SHS, OR 2.71, 95% CI (1.82,4.045); p = 0.02.ConclusionExposure to SHS was associated with reduced anthropometric measurements of the newborn and increased rate of LBW infants, irrespective of maternal BMI. Maternal obesity was associated with increased risk of delivering a macrosomic infant; conversely maternal underweight was associated with increased risk of delivering an LBW infant.

Influence of CYP2A6*4 Genotypes on Maternal Serum Cotinine Among Chinese Nonsmoking Pregnant Women

Serum cotinine is a common biomarker for smoking and secondhand smoke (SHS) exposure, but it can be affected by the activity of nicotine-metabolizing enzymes. This study investigated the influence of CYP2A6*4 genotypes on serum cotinine among nonsmoking pregnant women. We analyzed the data from 545 Chinese nonsmoking pregnant women in a case-control study on SHS exposure and birth outcomes in southern China. Participants self-reported their status and duration of SHS exposure during pregnancy right after delivery in hospital. Research staff used polymerase chain reaction to genotype CYP2A6*4 and enzyme-linked immunosorbent assay to measure cotinine levels in maternal serum samples collected before delivery. We stratified women by their self-reported SHS exposure status and CYP2A6*4 genotypes and then compared their median levels of serum cotinine. Among women who self-reported non-SHS exposure (n = 317), the median serum cotinine levels were 2.83ng/ml for those with CYP2A6*1/*1 genotype, 1.39ng/ml for CYP2A6*1/*4, and 0.77ng/ml for CYP2A6*4/*4, respectively. Among women who self-reported SHS exposure (n = 228), the median cotinine levels were 3.32ng/ml for those with CYP2A6*1/*1 genotype, 2.38ng/ml for CYP2A6*1/*4, and 1.56ng/ml for CYP2A6*4/*4, respectively. Strikingly, self-reported SHS-exposed women with CYP2A6*1/*4 or CYP2A6*4/*4 genotype had significantly lower (rather than higher) median cotinine levels than self-reported non-SHS-exposed women with CYP2A6*1/*1 genotype (p = .012). CYP2A6*4 genotype is associated with lower serum cotinine among Chinese nonsmoking pregnant women. Measuring CYP2A6*4 genotype may help to improve the validity of SHS exposure measurement by serum cotinine in pregnant women and possibly also in other nonpregnant populations.

Sleep disorders and secondhand smoke exposure in the U.S. population

Sleep disorders in the United States are pervasive and have been linked to increased risk of injury, morbidity, and mortality. Smoking is a known risk factor for sleep disorders; the association between secondhand smoke (SHS) exposure and sleep disorders is less clear. We sought to examine the relationship between SHS exposure and sleep disorders among a representative sample of U.S. adults (n = 4,123). Data were from the 2005-2006 National Health and Nutrition Examination Survey. Multivariable logistic regression models examined the association between both smoking and SHS exposure with two measures of sleep disorder (i.e., self-reported health care provider diagnosis and self-report of two or more sleep symptoms). SHS exposure status was based on a combination of self-report and serum cotinine levels. Relative to nonsmokers without SHS exposure, smokers were significantly more likely to have been diagnosed with a sleep disorder (odds ratio [OR] = 1.73 [95% CI = 1.16-2.60]) and more likely to report at least two sleep disorder symptoms (OR = 1.42 [95% CI = 1.09-1.84]). SHS-exposed nonsmokers were not significantly more likely to report a sleep disorder or sleep symptoms (OR = 1.43 [95% CI = 0.79-2.57] and OR = 1.03 [95% CI = 0.83-1.27]), respectively. Although smoking appears to play an important role in the prevalence of sleep disorders in the U.S. adult population, the role of SHS exposure is inconclusive and warrants further investigation.

Cross-Sectional and Prospective Associations Between Passive Smoking and Respiratory Symptoms at the Workplace

The purpose of the study is to investigate the cross-sectional and prospective relation between workplace secondhand smoke (SHS) exposure and respiratory symptoms. Cross-sectional data for workplace SHS exposure and respiratory symptoms were collected by using random digit dialing from 7336 never-smoking Hong Kong workers 15 years or older in 1997 to 1998. In the 2000 to 2001 follow-up, 2213 workers who remained never smoking, had the same SHS exposure status, worked at the same job for at least 2 years, and were not exposed to SHS at home at follow-up were included for prospective analysis. Cross-sectionally, SHS was associated significantly with frequent colds, cough and phlegm, throat problems, and the presence of any respiratory symptoms with adjusted odds ratios of 1.89 (95% confidence interval [CI], 1.66-2.15), 1.65 (95% CI, 1.35-2.02), 1.88 (95% CI, 1.63-2.15), and 1.96 (95% CI, 1.75-2.20) at baseline, each having significant linear associations with duration of exposure. SHS was not associated with rhinitis. Prospectively, consistent SHS exposure increased the risk for cough and phlegm and any respiratory symptoms by 48% (12% to 97%) and 54% (13% to 109%), respectively. This first non-Western population-based prospective study shows that workplace SHS exposure is associated significantly with frequent respiratory symptoms, both cross-sectionally and prospectively, thus providing strong evidence that the association is causal.