Association of exposure to secondhand smoke at home with early age at menarche in South Korea

Impact of Chemicals on the Age of Menarche: A Literature Review

A growing body of evidence suggests that chemicals interfere with the age of onset of menarche. We conducted a review in order to demonstrate the relationship between several categories of chemicals and menarche. We searched for English language papers using the Medline/PubMed database until April 2023. The chemical factors found to affect menarche were prenatal and antenatal smoke, phthalates, phenols, organochlorines, perfluoroalkyls and polyfluoroalkyls, metals, air pollutants and polybrominated diphenyl ethers. Low or high exposure to each chemical compound could affect the age of menarche, leading to early or delayed menarche. Furthermore, the results show that intrauterine exposure may have a different impact from antenatal exposure. There is evidence that endocrine-disrupting chemicals affect the age of menarche, but more research needs to be conducted.

The effect of environmental factors on precocious puberty in children: a case-control study

BACKGROUND

Recently the prevalence of precocious puberty development is increasing among Chinese children. Proper understanding of the risk factors for precocious puberty in children is pivotal as could help to improve children's health. This study aims to evaluate the effect of environmental factors on precocious puberty in children.

METHODS

We matched the cases and controls by age at the ratio of 1:1 (201 cases and 201 controls) for girls and 1:4 (24 cases and 96 controls) for boys. We used conditional logistic regression to explore the effect of environmental factors on precocious puberty, and a random forest model to identify the most important risk factor.

RESULTS

In the multivariate regression, cesarean section (OR = 1.99, 95% CI: 1.05, 3.76), child body mass index [BMI] (OR = 1.25, 95% CI: 1.10, 1.43), maternal BMI (OR = 1.13, 95%CI: 1.01, 1.26), and exposure to secondhand smoke several times a month but less than once a week (OR = 4.09, 95%CI: 1.79,9.35), and almost every day (OR = 6.48, 95% CI: 2.14, 19.56) were risk factors for precocious puberty in girls. While maternal height (OR = 0.82, 95% CI: 0.75, 0.88), paternal height (OR = 0.91, 95% CI: 0.85, 0.98), bedtime at night (OR = 0.30, 95% CI: 0.17, 0.51), and night sleep (OR = 0.43, 95% CI: 0.21, 0.86) were protective factors. In boys, only exposure to secondhand smoke several times a month but less than once a week (OR = 7.94, 95% CI: 1.25, 50.33) was a risk factor for precocious puberty. In the random forest model, Child BMI was the most important risk factor for precocious puberty in girls.

CONCLUSIONS

Our findings suggest that environmental factors were associated with precocious puberty in children, particularly in girls.

Status and correlates of children's exposure to secondhand smoke at home: A survey in Chongqing, China

INTRODUCTION

The home is the primary source of children's exposure to secondhand smoke. This study investigated the status and influencing factors of child exposure to secondhand smoke at home when people smoke in the household.

METHODS

Participants with at least one child living in their household from 10 communities in Chongqing were recruited and provided a self-administered questionnaire using a multistage proportional random sampling design from June to August 2021. The chi-squared test and binary logistic regression analyses were used to identify influencing factors.

RESULTS

The questionnaire completed by 1345 families showed that 631 (46.9%) families lived with smokers in their household, and 509 (80.7%) of those families reported that smoking occurred within the home while the children were present. Binary logistic regression analyses demonstrated that the time between waking up and household smokers having the first cigarette of the day (OR=0.44; 95% CI: 0.22-0.85), changes to smoking habits and behaviors within the last six months (OR=1.76; 95% CI: 1.06-2.90), attitudes towards tobacco control in the household (OR=2.91; 95% CI: 1.72-4.92), self-efficacy in maintaining a smoke-free home (OR=2.27; 95% CI: 1.36-3.79), having rules to maintain a smoke-free home (OR=3.25; 95% CI: 1.68-6.29), and the status of providing cigarettes to guests at home (OR=11.0; 95% CI: 1.33-90.8) were associated with exposure to SHS.

CONCLUSIONS

Education focusing on the impact of smoking on children's health should be encouraged. Smoke-free homes should be established, and smoking restrictions in the household should be enacted. Therefore, information about the available tobacco-control services should be given to family members and be used properly. It is an effective way to decrease the risk of at-home exposure to SHS for children, to overcome any obstacles in tobacco control.

Associations between pediatric asthma and age at menarche: evidence from the Indonesian Family Life Survey

OBJECTIVE

To examine the association between pediatric asthma and age at menarche, and to assess whether early life factors modify the association.

METHODS

This is a retrospective cross-sectional study using the Indonesian Family Life Survey Fifth Wave which had a total of 11 822 females aged 15-57 years to evaluate whether those with pediatric asthma were associated with earlier menarche, compared to females without asthma. We performed a weighted linear regression model adjusting for age, urbanicity, parental smoking, infectious disease history during childhood, childhood socioeconomic status, and health status during childhood. We also performed analyses by age at asthma diagnosis, interval length between asthma diagnosis and menarche, urbanicity, parental smoking, and infectious disease history during childhood.

RESULTS

In the adjusted model, females with pediatric asthma had an earlier average age at menarche by 5.2 months and those diagnosed with asthma at 5-8 years of age had the fastest acceleration by 14.9 months. The significant association persisted among those with 0-5 years interval between asthma diagnosis and menarche, who resided in urban areas, and those without infectious disease history during childhood.

CONCLUSIONS

Our findings showed that females with pediatric asthma were associated with an earlier age at menarche, and some early life factors modified the association. Better asthma management with more targeted strategies at those at risk of earlier menarche may improve the reproductive and future health of children with asthma. Future studies to elucidate the mechanisms between pediatric asthma and age at menarche are warranted.

Association between parents' country of birth and smoking risks in South Korean adolescents

This study aimed to determine whether significant associations exist between multicultural families and adolescent smoking risks in South Korea. Data from the Korea Youth Risk Behavior Web-based survey from 2016 to 2020 were analyzed. Participants were classified into four family types (South Korean mother-foreign father, South Korean father-foreign mother, both foreign parents, and both South Korean parents) according to their parents' country of birth and smoking was assessed using a self-reported questionnaire. A logistic regression analysis was used to examine the significance of the associations. Overall, 194,259 participants (boys: 94,793, girls: 99,466) enrolled in this study. Adolescents whose parents were born overseas were more likely to smoke than native South Korean adolescents (boys: odds ratio [OR] = 2.61, confidence interval [CI] = 1.79-3.81, girls: OR 3.94, CI 2.42-6.43). When the mother's country of birth was a developing country, there was an increased likelihood of girls smoking, and there was an increased likelihood of smoking among boys when the mother's country of birth was North Korea. When both parents were born abroad, and the mother's country of birth was a developing country, the likelihood of smoking risks among their multicultural teenage children increased. Policies and interventions need to be established and implemented to lower the smoking rate among multicultural teenagers.

Association of Mixed Use of Electronic and Conventional Cigarettes and Exposure to Secondhand Smoke With Prediabetes

CONTEXT

Despite previous studies regarding the association between smoking and diabetes, the effects of electronic cigarettes and secondhand smoke (SHS) on glucose metabolism and insulin sensitivity have not been fully elucidated.

OBJECTIVE

To examine the association of mixed electronic and conventional cigarette use and exposure to SHS with prediabetes.

DESIGN

Data from the 2014-2018 Korean National Health and Nutrition Examination Survey were analyzed.

SETTING

Nationwide population-based.

PARTICIPANTS

Of 39 199 participants, 22 385 participants (9490 men, 12 895 women) without diabetes were included. The main independent variables were smoking behaviors, including exposure to SHS.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Prediabetes (hemoglobin A1C of 5.7-6.4%).

RESULTS

Of 22 385 participants without diabetes, 6735 had prediabetes. Mixed cigarette use was associated with a 1.57-fold increase in the odds of prediabetes when compared with never-smoking [odds ratio (OR) = 1.57, 95% CI = 1.29-1.92] and a 1.27-fold increase when compared with conventional cigarette use only (OR = 1.27, 95% CI = 1.07-1.52). Participants who were current nonsmokers, but mixed users in the past had an increased risk of prediabetes (OR = 1.54, 95% CI = 1.04-2.13). There was no significant association between prediabetes and current nonsmoking in individuals with previous conventional cigarette use only. Among never-smokers, exposure to SHS significantly increased the risk of prediabetes (OR = 1.16, 95% CI = 1.04-1.30).

CONCLUSIONS

Mixed use of electronic and conventional cigarettes and exposure to SHS increased the risk of prediabetes. Further studies are required to comprehensively investigate the molecular biology underlying the effects of previous and current mixed use of electronic cigarettes and SHS on glucose metabolism.

Prenatal Exposure to Alcohol, Tobacco, and Coffee: Associated Congenital Complications and Adverse Birth Outcomes

A few studies to date have examined the association between prenatal exposure to alcohol, tobacco, and coffee, and congenital complications/adverse birth outcomes among South Korean populations. Thus, this study analyzed the data of 1675 Korean women with birth experience within the last 3 years for pregnancy-related health and nutritional behaviors and relative outcomes. During their pregnancies, 11.58% of the study population consumed alcohol at least once, 1.43% drank throughout all three trimesters, 1.13% smoked, 25.43% were exposed to secondhand smoking, and 28.18% consumed 3 coffees or more every day. Prenatal alcohol exposure was associated with 11.24 times increased risk of birth defects/disabilities [Odds Ratio (OR): 11.24, 95% Confidence Interval (CI) 1.07-117.86] and 10.66 times increased risk of inherited metabolic diseases (OR: 10.66, 95% CI: 1.08-104.82). Prenatal secondhand smoke exposure (OR: 1.62, 95% CI: 1.01-2.62) and coffee consumption (OR: 1.92, 95% CI: 1.22-3.03) was associated with increased risk of low birth weight. Such results were in alignment with that of previous studies and confirmed that prenatal alcohol, tobacco, and coffee exposure can have detrimental neonatal and maternal consequences.

Association between parents' smoking status and tobacco exposure in school-age children: assessment using major urine biomarkers

Children are at risk of exposure to secondhand smoke. We aimed to evaluate the extent of their exposure to it in relation to their parents' smoking status by using biomarkers relevant to smoking. We evaluated 847 school-age children (6-12 years) who lived with their parents, using data from the Korea National Health and Nutrition Examination Survey 2016-2018. Secondhand smoke exposure in children of non-smoking and smoking parents was assessed by measuring urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and cotinine concentrations. Overall, the parents of 482 (55.1%) children smoked and those of 392 (44.9%) children did not smoke. After adjusting for covariates, significantly higher concentrations of NNAL (β = 0.482, standard error [S.E.] = 0.065, P < 0.001) and cotinine (β = 0.472, S.E. = 0.06, P < 0.001) were found in children of smoking parents than in children of non-smoking parents. Children of parents who smoked a higher number of cigarettes showed higher NNAL and cotinine concentrations than children of non-smoking parents. Children with both parents who smoked showed the highest NNAL and cotinine concentrations. Children of smoking parents are at a higher risk of exposure to secondhand smoke. A smoke-free environment must be maintained to protect children from the harmful effects of secondhand smoke. Therefore, comprehensive national anti-smoking policies are required.