Grandmaternal smoking, asthma and lung function in the offspring: the Lifelines cohort study

The developmental origins of health and disease and intergenerational inheritance: a scoping review of multigenerational cohort studies

Epidemiologic research has increasingly acknowledged the importance of developmental origins of health and disease (DOHaD) and suggests that prior exposures can be transferred across generations. Multigenerational cohorts are crucial to verify the intergenerational inheritance among human subjects. We carried out this scoping review aims to summarize multigenerational cohort studies' characteristics, issues, and implications and hence provide evidence to the DOHaD and intergenerational inheritance. We adopted a comprehensive search strategy to identify multigenerational cohorts, searching PubMed, EMBASE, and Web of Science databases from the inception of each dataset to June 20th, 2022, to retrieve relevant articles. After screening, 28 unique multigenerational cohort studies were identified. We classified all studies into four types: population-based cohort extended three-generation cohort, birth cohort extended three-generation cohort, three-generation cohort, and integrated birth and three-generation cohort. Most cohorts (n = 15, 53%) were categorized as birth cohort extended three-generation studies. The sample size of included cohorts varied from 41 to 167,729. The study duration ranged from two years to 31 years. Most cohorts had common exposures, including socioeconomic factors, lifestyle, and grandparents' and parents' health and risk behaviors over the life course. These studies usually investigated intergenerational inheritance of diseases as the outcomes, most frequently, obesity, child health, and cardiovascular diseases. We also found that most multigenerational studies aim to disentangle genetic, lifestyle, and environmental contributions to the DOHaD across generations. We call for more research on large multigenerational well-characterized cohorts, up to four or even more generations, and more studies from low- and middle-income countries.

Maternal smoking around birth and its influence on offspring allergic diseases: A mendelian randomization study

Objective

The influence of maternal smoking around birth (MSAB) on offspring allergic diseases, specifically childhood asthma (CA), allergic rhinitis (AR), allergic conjunctivitis (AC), and atopic dermatitis (AD) remains incompletely understood. We performed a rigorous mendelian randomization (MR) study to obtain the unconfounded association between MSAB and allergic diseases in offspring with and without adjustment for the effect of breastfeeding.

Methods

Utilizing publicly available information of MSAB, breastfeeding, CA, AR, AC, and AD from large-scale genome-wide association studies (GWAS), we performed a two-sample mendelian randomization (TSMR) analysis to assess the respective causal relationship of MSAB and breastfeeding to allergic diseases in offspring. To get a reliable conclusion, MR Egger regression, weighted median, and inverse variance weighted (IVW) were employed to estimate the causality, with IVW as the primary analysis. Multivariate MR (MVMR) analysis was used to assess the effect of MSAB on allergic diseases after adjusting for breastfeeding's impact. Sensitivity analysis was conducted using the Cochran Q test, MR-Egger, and leave-one-out approaches to ensure the reliability and stability of results.

Results

The TSMR analysis demonstrated MSAB increased the risks of CA (PIVW = 0.013, OR: 1.018, 95%CI: 1.004 to 1.033) and AD (PIVW = 0.006, OR: 8.293, 95%CI: 1.815 to 37.884) in offspring. Conversely, breastfeeding decreased the risk of CA (PIVW <0.001, OR: 0.946, 95%CI: 0.918 to 0.974). MSAB still increased the risks of CA (P = 0.0497, OR: 1.013, 95%CI: 1.000017 to 1.026) and AD (P = 0.003, OR: 13.800, 95%CI: 2.490 to 269.246) after adjusting for breastfeeding. We observed no strong indication of a negative causality between MSAB and AC and AR.

Conclusion

Our findings provided robust evidence of the adverse effects of MSAB on offspring. We emphasized the urgency of smoking cessation around birth and the importance of breastfeeding even in smoking mothers.

Indoor environment in relation to recurrent childhood asthma in Yancheng, China: a hospital-based case-control study

This investigation explored the association between indoor environmental factors and childhood asthma in Yancheng, China. Asthma case (201 children with recurrent asthma) and control cohorts (242 healthy subjects) were recruited from a Traditional Chinese Medical (TCM) Hospital in Yancheng city, based on the results of an ISAAC questionnaire. Questionnaires regarding environmental risk factors were completed by the child's primary caregivers. To compare data on environmental VOCs and formaldehyde contents between asthma and control cohorts, we passively conducted a 10-day indoor and outdoor sampling. Breastfeeding was a major protective indoor environmental factor for recurrent asthma (adjusted odds ratio [aOR]: 0.368, 95% confidence interval [CI]: 0.216-0.627). Our analysis revealed that childhood recurrent asthma was intricately linked to a family history of asthma. Recurrent asthma was also associated with passive smoking [aOR2.115 (95%-CI 1.275-3.508)]. Analogous correlations were observed between household renovation or new furniture introduction and recurrent asthma [aOR3.129(95%-CI1.542-6.347)]. Benzene and formaldehyde were present in all examined homes. Enhanced benzene and formaldehyde concentrations were strongly evident among asthma versus control cohorts, and they were strongly correlated with augmented recurrent asthma risk. Home environment heavily regulates incidences of childhood recurrent asthma. Hence, actions against the indoor environmental risk factors described in this study may assist in the prevention of recurrent asthma among children.

A history of asthma may be associated with grandparents' exposures to stress and cigarette smoking

Introduction: Within human epidemiological studies, associations have been demonstrated between grandparental exposures during childhood and grandchildren's outcomes. A few studies have assessed whether asthma has ancestral associations with exposure to cigarette smoking, but results have been mixed so far. Material and methods: In this study we used four generations: (F0 great-grandparents, F1 grandparents, F2 parents, F3 study children) of the Avon Longitudinal Study of Parents and Children (ALSPAC) to determine whether there is evidence of associations between asthma in generations F2 or F3 and exposures to severe trauma in childhood and/or active cigarette smoking during the adolescence of grandmothers and grandfathers in generations F0 and F1 respectively, or of a history of a F0 or F1 grandmother smoking during pregnancy. Results: We have shown that: a) stress exemplified by the death of a F1 grandparent's parent during the grandparents' childhood was associated with increased risk of asthma in generation F3, especially if the grandparent involved was the paternal grandmother; b) if the grandparents of generations F0 or F1 smoked during adolescence (i.e. < 17 years), their grandchildren in generations F2 and F3 were more likely to have a history of asthma; c) paternal F1 grandmother's smoking in pregnancy was associated with her F3 grandchild's asthma at age 7; d) There were differences between the results for the grandsons and granddaughters of the paternal grandmother with exposure to smoking in adolescence and with smoking in pregnancy. e) The addition of all of the individual exposure variables to the different analyses often provided a considerable increase in goodness of fit compared with only adding demographic factors associated with asthma at P < 0.10 such as social class; this was particularly true when all four exposure variables were combined in one model, suggesting possible synergistic effects between them. Discussion: We have shown associations between all four types of exposure to the grandparents to be associated with asthma in the grandchildren, such that the results both depended on whether the male or female line was involved, and the sex of the grandchildren. It was notable that the paternal grandmother was particularly involved in many of the associations. We emphasize that these are exploratory analyses, that asthma diagnostic criteria likely changed over time and may not be consistent between generations, and that the results should be tested in other cohorts.

Limited Health Literacy and Its Associated Health Outcomes Among Adults With at Least 2 Atopic Diseases

BACKGROUND

Health literacy (HL) is essential for patients with multiple atopic diseases to improve their health, given the complexity of their disease and treatment regimens.

OBJECTIVE

To estimate the proportion of adults with multiple atopic diseases (at least 2 of atopic dermatitis, asthma, allergic rhinitis, and food allergy) in the Dutch general population and to evaluate the prevalence of limited HL, and its association with socioeconomic status (SES), lifestyle factors, and health-related quality of life (HR-QoL) in this patient population.

METHODS

This cross-sectional study was conducted within the Lifelines Cohort Study via sending an add-on digital questionnaire, including (among others) questions on atopic dermatitis, to all adult participants (n = 135,950) between February and May 2020. Data on asthma, allergic rhinitis, lifestyle factors, HR-QoL, and SES were extracted from baseline assessment between 2006 and 2013. Functional, communicative, and critical HL were measured by validated items from Chew and the Dutch Functional Communicative and Critical Health Literacy questionnaires between 2012 and 2016. Food allergy was measured by the Food Allergy Questionnaire between 2014 and 2016.

RESULTS

In total, 11.8% of the overall study population reported ever having multiple atopic diseases; of those, 23.6% reported having limited functional HL, with a higher prevalence among those with a low SES. Limited functional HL showed positive associations with smoking, obesity, chronic stress, a low diet quality, and decreased HR-QoL among subjects with multiple atopic diseases.

CONCLUSIONS

We identified an HL deficit, and its association with a low SES and poor health outcomes among patients with multiple atopic diseases. Further research is warranted to utilize a more extensive assessment to measure HL and include more health outcomes, such as treatment adherence and disease control.

Epigenetic regulation of immune function in asthma

Asthma is a common complex respiratory disease characterized by chronic airway inflammation and partially reversible airflow obstruction resulting from genetic and environmental determinants. Because epigenetic marks influence gene expression and can be modified by both environmental exposures and genetic variation, they are increasingly recognized as relevant to the pathogenesis of asthma and may be a key link between environmental exposures and asthma susceptibility. Unlike changes to DNA sequence, epigenetic signatures are dynamic and reversible, creating an opportunity for not only therapeutic targets but may serve as biomarkers to follow disease course and identify molecular subtypes in heterogeneous diseases such as asthma. In this review, we will examine the relationship between asthma and 3 key epigenetic processes that modify gene expression: DNA methylation, modification of histone tails, and noncoding RNAs. In addition to presenting a comprehensive assessment of the existing epigenetic studies focusing on immune regulation in asthma, we will discuss future directions for epigenetic investigation in allergic airway disease.

European progress in working towards a tobacco-free generation

Children have the right to grow up free from the hazards associated with tobacco smoking. Tobacco smoke exposure can have detrimental effects on children's health and development, from before birth and beyond. As a result of effective tobacco control policies, European smoking rates are steadily decreasing among adults, as is the proportion of adolescents taking up smoking. Substantial variation however exists between countries, both in terms of smoking rates and regarding implementation, comprehensiveness and enforcement of policies to address smoking and second-hand smoke exposure. This is important because comprehensive tobacco control policies such as smoke-free legislation and tobacco taxation have extensively been shown to carry clear health benefits for both adults and children. Additional policies such as increasing the legal age to buy tobacco, reducing the number of outlets selling tobacco, banning tobacco display and advertising at the point-of-sale, and introducing plain packaging for tobacco products can help reduce smoking initiation by youth. At societal level, health professionals can play an important role in advocating for stronger policy measures, whereas they also clearly have a duty to address smoking and tobacco smoke exposure at the patient level. This includes providing cessation advise and referring to effective cessation services.Conclusion: Framing of tobacco exposure as a child right's issue and of comprehensive tobacco control as a tool to work towards the ultimate goal of reaching a tobacco-free generation can help accelerate European progress to curb the tobacco epidemic. What is Known: • Tobacco exposure is associated with a range of adverse health effects among babies and children. • Comprehensive tobacco control policies helped bring down smoking rates in Europe and benefit child health. What is New: • Protecting the rights and health of children provides a strong starting point for tobacco control advocacy. • The tobacco-free generation concept helps policy-makers set clear goals for protecting future generations from tobacco-associated harms.