Serum cotinine cut-points for secondhand smoke exposure assessment in children under 5 years: A systemic review

The Diverging Trend in Exposure to Environmental Tobacco Smoke Among US Children

OBJECTIVE

Environmental tobacco smoke exposure (ETSE) was race/ethnicity-specific, but how the race/ethnicity-specific ETSE has changed over time, diverging or converging, remains unclear. We examined ETSE trends by race/ethnicity in US children aged 3-11 years.

METHODS

We analyzed the data of 9678 children who participated in the biennial National Health and Nutrition Examination Surveys, 1999-2018. ETSE was defined as serum cotinine ≥ 0.05 ng/ml, with ≥ 1 ng/ml as heavy exposure. For trend description, adjusted biennial prevalence ratios (abiPR: the ratio associated with a 2-year increase in time) were estimated by race/ethnicity. The prevalence ratios between races/ethnicities were used to quantify ethnoracial differences in different survey periods. Analyses were performed in 2021.

RESULTS

The overall ETSE prevalence was cut by almost half, from 61.59% (95% confidence interval = 56.55%, 66.62%) in the 1999-2004 survey to 37.61% (33.90%, 41.31%) in 2013-2018, exceeding the national 2020 health target (47.0%). However, the decrease occurred unequally between races/ethnicities. Heavy ETSE declined significantly in white [abiPR = 0.80 (0.74, 0.86)] and Hispanic children [0.83 (0.74, 0.93)], but insignificantly in black children [0.97 (0.92, 1.03)]. Consequently, the adjusted prevalence ratio between black children and white children increased from 0.82 (0.47, 1.44) in 1999-2004 to 2.73 (1.51, 4.92) in 2013-2018 for heavy ETSE. Hispanic children remained at the lowest risk throughout the study period.

CONCLUSION

Overall ETSE prevalence was cut by half between 1999 and 2018. However, due to uneven declines, the gaps between black children and others have expanded in heavy ETSE. Special vigilance is needed in preventive medicine practice with black children.

The association between passive smoking and sleep quality in a Chinese hypertensive population: A cross-sectional study

INTRODUCTION

This study evaluates the association between passive smoking, specifically secondhand smoke (SHS) and thirdhand smoke (THS) exposure, and sleep quality in a hypertensive population.

METHODS

We enrolled 1427 eligible hypertensive patients from a 2022 national cross-sectional survey in China. Data on tobacco smoke exposure and sleep were collected via questionnaires. Multiple logistic regression and linear regression were employed to assess the relationship between passive smoking and sleep quality characteristics, as well as the correlation between passive smoking exposure characteristics and sleep quality.

RESULTS

Among 589 hypertensive patients with no tobacco smoke exposure, 679 exposed to SHS, and 159 exposed to THS, SHS exposure was associated with a higher risk of poor sleep quality, even after adjusting for potential confounding factors (β=0.10; 95% CI: 0.32-0.95). No significant relationship was observed between THS exposure and sleep quality. SHS exposure was associated with various sleep quality characteristics, including shorter sleep duration (AOR=1.71; 95% CI: 1.06-2.76) and increased frequency of 1-2 sleep disturbances per week (AOR=1.68; 95% CI: 1.25-2.26). Individuals exposed to SHS were more likely to experience poorer subjective sleep quality (AOR=1.53; 95% CI: 1.07-2.21) and have sleep efficiency <65% (AOR=1.82; 95% CI: 1.22-2.71). Exposure to passive smoking at home, in the community, in public places, exposure to passive smoking with family and friends, and increased frequency of exposure, were all associated with a higher risk of poor sleep quality.

CONCLUSIONS

Our study suggests that SHS exposure in hypertensive populations is associated with poor sleep quality and various characteristics of sleep quality. No significant association was found between THS exposure and sleep quality. These findings underscore the need to enhance tobacco control efforts in China, particularly for individuals with chronic diseases, to safeguard public health.

Association of chronic cough with exposure to polycyclic aromatic hydrocarbons in the US population

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants formed during the incomplete combustion of organic substances, such as coal and oil. PAHs exposure is known to increase the incidence of respiratory diseases; however, limited research has focused on their impact on chronic cough. In this study, we utilized data from the National Health and Nutritional Examination Surveys (NHANES) from 2003 to 2012. Chronic cough was defined as 'coughing most days for three consecutive months or more'. Employing survey-weighted multivariate logistic regression models, we identified positive associations between all six PAHs metabolites (1-NAP, 2-NAP, 3-FLU, 2-FLU, 1-PHE, and 1-PYR) found in urine and the presence of chronic cough. Furthermore, results from restricted cubic spline modeling revealed a nonlinear relationship between urinary levels of 1-NAP, 2-NAP, 3-FLU, 2-FLU, and 1-PYR and the risk of chronic cough. Co-exposure modeling unveiled the combined effects of multiple exposures and the relative contributions of each PAHs. Notably, co-exposure to PAHs was positively associated with an increased risk of chronic cough, where 2-FLU emerged as the primary contributor to this association. These findings were particularly pronounced in individuals with high cotinine exposure (≥0.05 ng/mL). In conclusion, this study presents epidemiological evidence linking PAHs exposure to an elevated risk of chronic cough. Further prospective investigations are warranted to corroborate these findings.

Saliva and Exhaled Breath Condensate Correlate With Serum in 4-12-Year-Olds Exposed to Secondhand Electronic Cigarette Vapors: A Pilot Study

Electronic cigarette use is highest among adults of child-bearing age. Many parents that use electronic cigarettes believe that secondhand exposure of electronic cigarette vapors for their children is not dangerous and is less harmful than secondhand exposure to traditional cigarette smoke. These beliefs may prompt excessive secondhand exposure to electronic cigarette vapors for their children. Little research has been done to document exposure in children. The traditional biological method of exposure detection is through a blood draw, which is difficult and undesirable in children. The purpose of this study was to assess the feasibility of using saliva and exhaled breath condensate as non-invasive biomatrices for detecting secondhand electronic cigarette vapor exposure in children. In this cross-sectionally designed study, we recruited 22 children exposed to electronic cigarette vapors and 26 non-exposed between the ages of 4-12 years. We compared metabolic features across three biomatrices, blood, saliva, and exhaled breath condensate. We noted moderate to strong pairwise, sample-specific, and feature-specific adjusted correlations. Annotated features associated with direct and secondhand electronic cigarette exposure were noted. These results demonstrate that less invasive biomatrices may be used to detect features associated with secondhand electronic cigarette vapor exposure in children.

Secondhand and thirdhand smoke: a review on chemical contents, exposure routes, and protective strategies

Secondhand smoke (SHS: a mixture of sidestream and mainstream smoke) and thirdhand smoke (THS: made up of the pollutants that settle indoors after smoking in closed environments) are a significant public health concern. SHS and THS contain various chemicals which can be released into the air or settle on surfaces. At present, the hazards of SHS and THS are not as well documented. In this review, we describe the chemical contents of THS and SHS, exposure routes, vulnerable groups, health effects, and protective strategies. The literature search was conducted for published papers on September 2022 in Scopus, Web of Science, PubMed, and Google Scholar databases. This review could provide a comprehensive understanding of the chemical contents of THS and SHS, exposure routes, vulnerable groups, health effects, protective strategies, and future researches on environmental tobacco smoke.

Tobacco Smoke Exposure in Pregnant Dogs: Maternal and Newborn Cotinine Levels: A Pilot Study

Active and passive smoking in pregnant women is associated with perinatal morbidity and mortality risk, including abortion, preterm birth, low birthweight, and malformations. No data are available on intrauterine exposure to smoking during pregnancy in dogs. This study aimed to fill this gap by exploring the detectability and quantity of cotinine, the major metabolite of nicotine, in maternal (serum and hair) and newborn (amniotic fluid and hair) biospecimens collected at birth in dogs. For this purpose, twelve pregnant bitches, six exposed to the owner's smoke and six unexposed, were enrolled. A further six non-pregnant bitches exposed to passive smoke were included to investigate the role of pregnancy status on cotinine uptake. Exposed dogs, dams, and puppies had greater cotinine concentrations than unexposed ones. Although without statistical significance, serum and hair cotinine concentrations were higher in pregnant compared to non-pregnant bitches, suggesting a different sensitivity to tobacco smoke exposure during gestation. The present results provide evidence for cotinine transplacental passage in the dog. It is conceivable that fragile patients such as pregnant, lactating, and neonate dogs may be more susceptible to the harmful effects of second-hand smoke exposure. Owners should be sensitized to the risk of smoke exposure for their pets.