Heated tobacco product use and hypertensive disorders of pregnancy and low birth weight: analysis of a cross-sectional, web-based survey in Japan

Relationship Between Heated Tobacco Products and Placental Abruption: A Prospective Cohort Study Using Online Questionnaire

BACKGROUND

Placental abruption (PA) is a critical obstetric complication, with maternal smoking recognized as a key risk factor. Despite the increased use of heated tobacco products (HTPs), the impact of HTPs remains unclear. This study investigated whether pregnant women using HTPs are at a higher risk of PA than non-users.

METHODS

We analyzed data from "the Japan COVID-19 and Society Internet Survey," a prospective, self-reported online survey cohort. Questionnaires were randomly distributed between July 28, 2021, and August 30, 2021. Pregnant respondents in 2021 were invited to complete an additional survey from February 14, 2022, to February 28, 2022. We set the outcome as the absolute risk difference (aRD) and relative risk ratio (rRR) of PA incidence due to smoking HTPs in the first trimester of pregnancy. The sample size included 12 836 participants. We calculated outcomes using a generalized linear model (GLM) and inverse probability of treatment weighting (IPTW). We also performed a Bayesian approach and multiple-bias analysis for sensitivity analysis.

RESULTS

We found the robust aRD of 0.07 (95% confidence interval (CI): 0.06, 0.09) and the rRR of 11.3 (95% CI: 7.5, 17.0). Multiple bias analyses showed that unmeasurable confounders would need to have at least an rRR = 14 relationship with both exposure and outcome to disprove the observed association. There has not been post hoc analysis or secondary use of data.

CONCLUSION

Early pregnancy use of HTPs is associated with an increased risk of PA.

Should the Definition of Low Birth Weight Be Same in Every Ethnicity Considering the DOHaD Concept?

Low birth weight (LBW) is a significant concern not only because of its association with perinatal outcomes, but also because of its long-term impact on future health. Despite the physical differences among individuals of different ethnicities, the definition of LBW remains the same for all ethnicities. This study aimed to explore and discuss this issue. We compiled national data from several countries and found that maternal height was negatively correlated with LBW incidence. We discovered the INTERGROWTH-21st chart may not be suitable for the Japanese population, as the Japanese birth weight chart differs from the INTERGROWTH-21st chart. Researchers have reported different LBW cutoff values used to assess adverse perinatal outcomes for different countries. However, there is currently no definition of LBW independent of the mother's country of origin that can be used for predicting the risk of adverse health outcomes. Therefore, the current era of personalized healthcare may be the perfect time to establish a standard definition of LBW which is independent of the mother's country of origin. Considering the future of healthcare, it seems an apt time to discuss the development of a more meaningful definition of LBW that can be applied across ethnicities. Further research is needed to investigate the cutoff values of LBW in every ethnicity.

The Association between Perinatal Complications and Adverse Childhood Experiences: Findings from a Nationwide Online Survey

OBJECTIVE

 This study aimed to evaluate the association between maternal adverse childhood experiences (ACEs) levels and the risk of perinatal complications.

STUDY DESIGN

 This is a retrospective cohort study of 5,693 mother-child pairs born between 2019 and 2021, who completed questionnaires on maternal ACE scores and perinatal complications such as preterm birth, low birth weight infants, pregnancy-induced hypertension (PIH), gestational diabetes mellitus (GDM), and premature rupture of membrane (PROM). Odds ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression according to the three ACE score groups after adjusting for confounding factors such as maternal age, child's sex, household income, and maternal education.

RESULTS

 Maternal ACEs have a significant positive correlation with preterm birth (OR: 1.42, 95% CI: 1.09-1.86, p for trend = 0.009), PIH (OR: 1.55, 95% CI: 1.17-2.07, p for trend = 0.002), and PROM (OR: 1.42, 95% CI: 1.09-1.84, p for trend = 0.01). These associations remained unchanged when stratified according to smoking, alcohol consumption, and obesity.

CONCLUSION

 Maternal ACEs were associated with the risk of perinatal complications such as preterm birth, PIH, and PROM.

KEY POINTS

· Maternal ACEs are linked to higher risks of preterm birth, PIH, and PROM.. · Parental divorce, emotional abuse, and neglect were the most common ACEs among Japanese mothers.. · Mothers with ACEs score ≥ 2 had a higher risk of perinatal complications..

Association between cigarette and heated tobacco use and breastfeeding cessation within 6 months postpartum in Japan: an internet-based cross-sectional study

This study examined the association between cigarette and heated tobacco product (HTP) use before and during pregnancy and after six months postpartum and premature breastfeeding cessation (within 6 months postpartum). An internet-based cross-sectional survey was conducted from July to August 2021 in Japan, and the data of 4,005 women who gave birth between January 2019 and February 2021 were analyzed. The Poisson regression model with robust error variance showed that pre-pregnancy cigarette-only (adjusted prevalence ratio [aPR], 1.34; 95% confidence interval, [CI] 1.06 - 1.70) and combination users (i.e., cigarettes and HTPs) (aPR, 1.34; 95% CI, 1.02 - 1.77) and quitters during pregnancy (aPR, 1.37; 95% CI, 1.15 - 1.64) were more likely to cease breastfeeding prematurely than non-users. HTP-only users before (aPR, 1.32; 95% CI, 0.99 - 1.76) and during pregnancy (aPR, 1.08; 95% CI, 0.61 - 1.92) had no association with premature breastfeeding cessation. The multinomial logistic regression model showed that premature breastfeeding cessation was associated with cigarette-only (adjusted relative risk ratios [aRRR], 2.17; 95% CI, 1.22 - 3.85) and combination-use (aRRR, 2.62; 95% CI, 1.17 - 5.87) after 6 months postpartum. Women with cigarette or combination-use histories, despite quitting during pregnancy, tended to terminate breastfeeding prematurely, but this was not the case for HTP-only users.

Association between adverse childhood experiences and pregnancy morbidities: A nationwide online-based cross-sectional study

OBJECTIVE

To examine the association between adverse childhood experiences (ACEs) and pregnancy morbidities, including preterm birth (PTB), gestational diabetes (GDM), preeclampsia, and small-for-gestational-age (SGA) among the general population in Japan.

METHODS

The data were from the JACSIS study, an online-based nationwide survey conducted from July to August 2021 in Japan (N = 5444). ACEs included physical, sexual, and psychological abuse, neglect, childhood poverty, bully victimization, domestic violence, parental death, and parental divorce. Pregnancy morbidities, including PTB, GDM, preeclampsia, and SGA were identified through questionnaires. A multivariable logistic regression model was applied.

RESULTS

Of 5444 women, 2778 (51.0%) had no ACEs, and 374 (6.9%) had four or more ACEs. A dose-response association was found between total ACE score and PTB and preeclampsia (p-value: 0.016 and 0.001). Women with four or more ACE scores showed higher risks of preeclampsia (adjusted odds ratio [aOR] [95% confidence interval, CI]: 3.06 [1.57-5.94], p-value: 0.001). Besides, those with two or three ACEs had higher risks of PTB (aOR [95%CI]: 1.42 [1.01-2.02], p-value: 0.046, and aOR [95%CI]: 1.61 [1.04-2.50], p-value: 0.041), and women with one ACE showed a higher risk of GDM (aOR [95%CI]: 1.34 [1.02-1.77], p-value: 0.035). SGA was not associated with ACEs.

CONCLUSION

ACEs were associated with an increased risk of PTB, preeclampsia, and GDM, but not SGA among the general population in Japan.

The Product Science of Electrically Heated Tobacco Products: An Updated Narrative Review of the Scientific Literature

Heated tobacco products represent a novel category of tobacco products in which a tobacco consumable is heated to a temperature that releases nicotine from the tobacco leaf but not to a temperature sufficient to cause combustion. Heated tobacco products may therefore have the potential to be a less harmful alternative for adult smokers who would otherwise continue to smoke cigarettes, as their use should result in exposure to substantially fewer and lower levels of toxicants. This update represents a two-year extension to our previous narrative review, which covered peer-reviewed journal articles published up to August 31, 2021. The scientific evidence published between 2021 and 2023 continues to indicate that aerosols produced from heated tobacco products contain fewer and substantially lower levels of harmful and potentially harmful constituents and that these observed reductions consistently translate to reduced biological effects in both in vitro and in vivo toxicological studies. Biomarker and clinical data from studies in which product use is controlled within a clinical setting continue to suggest changes in levels of biomarkers of exposure, biomarkers of potential harm, and clinical endpoints indicating the potential for reduced harm with switching to exclusive use of heated tobacco products in adult smokers. Overall, the available peer-reviewed scientific evidence continues to indicate that heated tobacco products offer promise as a potentially less harmful alternative to cigarettes, and as such, the conclusions of our original narrative review remain valid.

Mother-to-infant bonding difficulties are associated with future maternal depression and child-maltreatment behaviors: A Japanese nationwide longitudinal study

BACKGROUND

Mother-to-infant bonding difficulties (MIBD) are considered risk factors for postpartum depression and child-maltreatment behaviors. However, few longitudinal studies have examined this hypothesis. This study aims to explore the relationship between MIBD and subsequent maternal depression and child-maltreatment behaviors using longitudinal data from a 2021 Japanese nationwide survey.

METHODS

We studied 658 first-time mothers who had given birth within the past year and had not reported postpartum depression or child-maltreatment behaviors at baseline. The Japanese version of Mother-to-Infant Bonding Scale (MIBS) was used to measure MIBD. Subjects were monitored for six months and subsequently completed the Edinburgh Postnatal Depression Scale and responded to inquiries about child-maltreatment behaviors.

RESULTS

After adjusting for covariates, MIBD was associated with higher odds of maternal depression (OR=1.737, 95 % CI [1.078, 2.797]) and child-maltreatment behaviors (OR=2.040, 95 % CI [1.401, 2.970]) six months later. Further analysis indicated that MIBD was particularly associated with a heightened risk of emotional abuse (OR=2.172, 95 % CI [1.486, 3.176]). Sensitivity analysis confirmed these findings through multiple approaches, such as applying inverse probability weighting to mitigate selection bias, using an alternative MIBS cutoff score of 5, and adopting a time-varying model to account for the dynamic nature of depressive symptoms and child-maltreatment behaviors.

CONCLUSION

Proactive screening for MIBD could serve as a valuable tool in the early detection of maternal depression and potential child-maltreatment behaviors.

The prevalence and risk factors of suicidal ideation in women with and without postpartum depression

AIM

Suicidal ideation (SI) is a severe mental health issue in the postpartum period. As depression is a major risk factor of SI, it is often considered that the risk factors of SI are the same as those of postpartum depression. However, SI occurs in women without postpartum depression as well. The aim of this study is to separately examine the prevalence and risk factors of SI in postpartum women with and without depression.

METHODS

We used data of 5688 postpartum women from a 2021 Japanese nation-wide survey, whose age and geographical distributions were nationally representative. Postpartum depression was evaluated with the Edinburgh Postnatal Depression Scale (EPDS) and SI was measured with the 10th item of EPDS.

RESULTS

The prevalence of SI in women with and without depression (EPDS≥9) was 51.8 % and 3.3 %, respectively. Younger age and low family support were risk factors common to both women with and without depression. Being single, currently working, history of depressive disorders, and family members' visits to support being cancelled were risk factors of SI for women with depression. In contrast, primipara, history of psychiatric disorders other than depressive disorders, infectious disease other than colds during pregnancy, and feeling of loneliness increased since COVID-19 were risk factor of SI for women without depression.

CONCLUSION

Although with a low prevalence, SI occurs in women without postpartum depression, which has unique risk factors indicating distinct psychopathological mechanisms. These findings call for tailored SI intervention strategies according to whether postpartum depression is present or not.

Association Between Smoking and Hypertension in Pregnancy Among Japanese Women: A Meta-analysis of Birth Cohort Studies in the Japan Birth Cohort Consortium (JBiCC) and JECS

BACKGROUND

Recent literature suggest the effect of maternal smoking on risk of hypertensive disorders in pregnancy (HDP) and preeclampsia may differ by ethnicity; however, studies on Asians are limited.

METHODS

We investigated the association of maternal smoking with HDP and preeclampsia using a common analysis protocol to analyze the association in six birth cohorts participating in a Japanese consortium of birth cohorts (JBiCC). Results were compared with-published results from cohorts not included in this consortium, and, where possible, we produced a meta-analysis including these studies.

RESULTS

Meta-analysis of four cohort studies including 28,219 participants produced an odds ratio (OR) of 1.24 (95% confidence interval [CI], 0.88-1.87) for the effect of smoking beyond early pregnancy compared to women who did not smoke during pregnancy. These results combined with those from the Japan Environment and Children's Study (JECS) yielded an OR of 1.19 (95% CI, 1.00-1.43, P = 0.056). Meta-analysis results for categories of smoking volume were insignificant, but when combined with JECS yielded an OR of 0.86 (95% CI, 0.65-1.12) for smoking 1-4 cigarettes, 1.25 (95% CI, 0.98-1.60) for smoking 5-9 cigarettes, and 1.27 (95% CI, 1.04-1.54) for smoking 10 or more cigarettes per day. All effects were insignificant for preeclampsia.

CONCLUSION

Our results suggest that the protective effects of smoking longer and smoking more on HDP and preeclampsia repeatedly observed among Europeans and North Americans likely do not hold for the Japanese.

The diagnostic accuracy of the Edinburgh Postnatal Depression Scale without the self-harm item

The Edinburgh Postnatal Depression Scale (EPDS) is the most commonly used screening tool for perinatal depression. However, the 10th item of the EPDS intended to evaluate suicide ideation does not accurately capture suicide ideation and may cause psychological distress. Whereas endorsement of the strongest agreement "yes, quite often" on this item may be associated with suicide ideation, the response on this frequency is perfectly predicted by the EPDS full score. The discard of this item, therefore, is preferred. In the current study, using data from a nation-wide internet survey conducted in Japanese postpartum (n = 5688) and pregnant women (n = 1639), we show that the EPDS-9 without the 10th item correlates perfectly with the full EPDS or EPDS-10. Furthermore, the EPDS-9 and EPDS-10 have equivalent performance in differentiating participants' self-reported depression diagnosis as well as Kessler Psychological Distress Scale (K6)-based screening of depression. Lastly, at the cutoff of 9, the EPDS-9 performs well in predicting participants' response on the 10th item of EPDS; specifically, the sensitivity of differentiating frequent thoughts of self-harm is 0.968 and 1 in postpartum and pregnant women, respectively. Therefore, the EPDS-9 performs equivalently to EPDS-10 and can be considered to replace EPDS-10 in future use.

Maternal heated tobacco product use during pregnancy and allergy in offspring

BACKGROUND

Little is known about the association between maternal use of heated tobacco products (HTPs) during pregnancy and the onset of allergy among offspring. This study aimed to determine whether maternal HTP smoking is associated with allergy in their offspring and to evaluate the potential dose-response association.

METHODS

In this web-based, cross-sectional survey conducted in July and August 2021 in Japan, we investigated 5688 pairs of postpartum women and infants (<3 years). Clinical diagnoses of infant asthma, rhinitis, conjunctivitis, or atopic dermatitis were reported. Using multilevel Poisson regression, we estimated the prevalence ratios (PRs) and 95% confidence intervals (CIs) of allergy in infants with HTP smoking categories cross-classified by pregnancy periods, and adjusted for potential covariates including maternal cigarette smoking and partner's smoking status. Non-smokers served as the reference group.

RESULTS

In total, 2.4% women smoked HTPs during pregnancy. Allergy occurred in 7.8% of the infants. The prevalence of allergy increased among the offspring of current HTP smokers during pregnancy at 15.2% (PR = 1.98, 95% CI 1.28-3.05); this association was the most pronounced during the first trimester but attenuated before pregnancy and postpartum. Dose-response associations were observed, for example a one-unit increase in daily maternal HTP use during pregnancy was associated with a 5% increase in allergy onset. Sub-group analyses excluding cigarette smokers during pregnancy and sensitivity analyses using the International Study of Asthma and Allergies in Childhood questionnaire showed a similar pattern.

CONCLUSIONS

Maternal HTP smoking during pregnancy is associated with allergy in the offspring.

COVID-19 vaccine literacy and vaccine hesitancy among pregnant women and mothers of young children in Japan

BACKGROUND

Delays in the spread of vaccination have been recognized as an urgent public health issue in the context of the COVID-19 pandemic. Vaccine literacy (VL) is a critical determinant of vaccine uptake; however, little is known about VL among pregnant women and mothers of young children.

METHODS

We analyzed data from a nationwide, cross-sectional internet survey in Japan on VL and vaccine hesitancy, conducted with 1,639 pregnant women and 5,688 mothers of young children who had given birth after July 2019, between July 24 and August 30, 2021.

RESULTS

Vaccine hesitancy was observed in 51.1 % of pregnant women and 31.9 % of mothers of young children. The risk of vaccine hesitancy was significantly higher among pregnant women with lower interactive/critical skills (risk ratio [RR] 2.10, 95 % confidence interval [CI] 1.59, 2.78, p < 0.001), although functional skills did not significantly correlate with vaccine hesitancy. For mothers of young children, we found a significantly higher risk of vaccine hesitancy among those with low VL functional skills (RR 1.38, 95 % CI 1.19, 1.61), p < 0.001) and low interactive/critical skills (RR 1.29, 95 % CI 1.10, 1.50, p = 0.001).

CONCLUSIONS

Our findings suggest that aiding individuals to correctly evaluate vaccine-related information is critical for improving vaccine acceptance rates among both pregnant women and mothers of young children. Meanwhile, improving the comprehensibility of communication toolkits may be important for women with children but have a limited effect among pregnant women.

Association between Heated Tobacco Product Use during Pregnancy and Fetal Growth in Japan: A Nationwide Web-Based Survey

Combustible cigarette smoking impacts fetal growth during pregnancy. However, the risk associated with heated tobacco products (HTPs) remains unclear. This nationwide cross-sectional study investigated whether HTP use during pregnancy is associated with small for gestational age (SGA) outcomes among 5647 post-delivery women with singleton pregnancies, which were divided into four groups: lifetime never-smokers, former smokers before pregnancy, and current smokers for each of the tobacco products during pregnancy (sole HTP and sole combustion smokers). Information on the prevalence of SGA, defined as birth weight and height below the 10th percentile, was retrieved from the Maternal and Child Health Handbooks of post-delivery women. Using logistic regression, the association between sole HTP smokers during pregnancy and SGA, adjusted for covariates, with lifetime never-smokers as reference, was investigated. The prevalence was: current sole HTP smokers during pregnancy, 1.8% (102/5647); and SGA, 2.9% (164/5647). Sole HTP smokers during pregnancy had a higher prevalence of SGA (5.9% [6/102] vs. 2.7% [111/4144]) with an adjusted odds ratio (OR) of 2.50 (95% confidence interval [CI], 1.03-6.05) than lifetime never-smokers. Among sole combustion smokers, the adjusted OR for SGA was 1.95 (95% CI, 0.81-4.67). In Japan, HTP smoking during pregnancy may be associated with an increased risk for SGA.

The Association between Types of COVID-19 Information Source and the Avoidance of Child Health Checkups in Japan: Findings from the JACSIS 2021 Study

The coronavirus disease 2019 (COVID-19) pandemic can affect children's well-being through mothers' avoidance of health checkups for children due to media portrayal of the disease. This study investigated the association between the type of information source for COVID-19 received by mothers and the avoidance of their children's health checkups. The study was an online-based survey, and the participants comprised 5667 postpartum women with children aged under 2 years during the study period. We analyzed the analytic sample and three groups of women with children aged 0-3 months, 4-6 months, and 6 months or older according to the timing of children's health checkups in Japan. Among the participants, 382 women (6.7%) avoided their children's health checkups. Multivariate logistic regression analysis revealed that mothers with children over 6 months who used magazines as an information source about COVID-19 tended to avoid their children's health checkups (adjusted odds ratio (aOR): 3.19; 95% confidence interval (CI): 1.68-6.05) compared with those who did not. In contrast, those using public websites were less likely to avoid their children's health checkups (aOR 0.58, 95% CI 0.43-0.77). This study showed that specific types of information source on COVID-19 could have varying effects on mothers' decisions about their children's health checkups.

Association of Paternity Leave with Impaired Father–Infant Bonding: Findings from a Nationwide Online Survey in Japan

Although the number of fathers taking childcare leave is increasing, the impact of paternity leave on father–infant bonding remains to be fully investigated. This study aimed to assess the association between paternity leave and father–infant bonding among fathers with children under two years old. A cross-sectional study was performed using data from the Japan COVID-19 and Society Internet Survey study, a nationwide online survey conducted between July and August 2021 (N = 1194). Father–infant bonding was assessed by the Japanese version of the Mother–Infant Bonding Scale (MIBS-J), which comprised two subscales (lack of affection (LA), and anger and rejection (AR)), with a higher score denoting poor bonding. Four hundred (33.5%) fathers self-reported taking childcare leave. Paternity leave was associated with higher total MIBS-J score and AR score after adjusting for covariates (coefficient 0.51; 95% confidence interval (CI) 0.06–0.96, coefficient 0.26; 95% CI 0.03–0.49, respectively), but not with LA score (coefficient 0.10; 95% CI −0.13–0.34). There was no trend in the association between paternity leave and total MIBS-J score by children’s age group (p for trend = 0.98). Paternity leave was associated with impaired bonding, especially with increased anger and rejection, among fathers with children under two years of age.

The prevalence of COVID-19 vaccination and vaccine hesitancy in pregnant women: an internet-based cross-sectional study in Japan

Background

Reluctance of people to receive recommended vaccines is a growing concern, as distribution of vaccines is considered critical to ending the COVID-19 pandemic. There is little information regarding pregnant women’s views toward coronavirus vaccination in Japan. Therefore, we investigated the vaccination rate and reasons for vaccination and vaccine hesitancy among pregnant women in Japan.

Methods

We conducted a cross-sectional study involving 1,791 pregnant women using data from the Japan “COVID-19 and Society” Internet Survey, conducted from July to August 2021, and valid response from 1,621 respondents were analyzed. We defined participants with vaccine hesitancy as those who identified with the statement “I do not want to be vaccinated” or “I want to ‘wait and see’ before getting vaccinated.” Multivariate Poisson regression analysis was used to investigate the factors contributing to vaccine hesitancy.

Results

The prevalence of vaccination and vaccine hesitancy among pregnant women was 13.4% (n = 217) and 50.9% (n = 825), respectively. The main reasons for hesitancy were concerns about adverse reactions and negative effects on the fetus and breastfeeding. Vaccine hesitancy was significantly associated with the lack of trust in the government (adjusted prevalence ratio, 1.26; 95% confidence interval, 1.03–1.54). Other factors, such as age, educational attainment, and state of emergency declaration, were not associated with vaccine hesitancy.

Conclusions

COVID-19 vaccination is not widespread among pregnant women in Japan, although many vaccines have been shown to be safe in pregnancy. Accurate information dissemination and boosting trust in the government may be important to address vaccine hesitancy among pregnant women.

Association between Smoking during Pregnancy and Short Root Anomaly in Offspring

Short root anomaly (SRA) is a dental anomaly with short dental roots and its pathogenesis is poorly understood. This study investigated the association between maternal smoking during pregnancy and SRA in offspring. A survey was conducted on 558 children aged 8–16 years from two public schools in Ulaanbaatar, Mongolia. SRA was diagnosed using cases with a root-crown ratio of maxillary central incisors of ≤1.0. A questionnaire survey was conducted to assess maternal lifestyle habits. Multiple logistic regression was used to analyse the association between maternal smoking during pregnancy and SRA in offspring after adjusting for possible confounders. The prevalence of SRA in these children was 14.2%. Children whose mothers smoked from pregnancy to date were found to be 4.95 times (95% confidence interval [CI]: 1.65–14.79) more likely to have SRA than those whose mothers never smoked, after adjusting for possible confounders. Additionally, children whose mothers had been exposed to passive smoking during pregnancy were found to be 1.86 times (95% CI: 1.02–3.40) more likely to have SRA than those whose mothers had not been exposed to passive smoke. Our population-based study suggests that maternal and passive smoking exposure during pregnancy can affect tooth root formation in children.