Exposomal research in the context of birth cohorts: What have they taught us?

Addressing Exposome: An Innovative Approach to Environmental Determinants in Pediatric Respiratory Health

Developmental age is particularly vulnerable to impacts of environmental exposures. Until recent years, the field of environment and child health has predominantly relied on the study of single exposure-health effect relationships. The exposome is an emerging concept in epidemiology, encompassing the totality of the exposures experienced by an individual throughout life and their changes over time. This innovative approach provides a risk profile instead of individual predictors. Exposome research may contribute to better understand the complex relationships between environmental exposures and childhood respiratory health, in order to implement prevention strategies and mitigate adverse health outcomes across the life span. Indeed, an accurate assessment of the exposome needs several measurements as well as different technologies. High-throughput "omics" technologies may be promising tools to integrate a wide range of exposures. However, analyzing large and complex datasets requires the development of advanced statistical tools. This narrative review summarizes the current knowledge on exposome-based approaches in pediatric respiratory health. Further, it explores practical implementation, associated evidence gaps, research limitations and future research perspectives.

Achieving Precision Medicine in Allergic Disease: Progress and Challenges

Allergic diseases (atopic dermatitis, food allergy, eosinophilic esophagitis, asthma and allergic rhinitis), perhaps more than many other traditionally grouped disorders, share several overlapping inflammatory pathways and risk factors, though we are still beginning to understand how the relevant patient and environmental factors uniquely shape each disease. Precision medicine is the concept of applying multiple levels of patient-specific data to tailor diagnoses and available treatments to the individual; ideally, a patient receives the right intervention at the right time, in order to maximize effectiveness but minimize morbidity, mortality and cost. While precision medicine in allergy is in its infancy, the recent success of biologics, development of tools focused on large data set integration and improved sampling methods are encouraging and demonstrates the utility of refining our understanding of allergic endotypes to improve therapies. Some of the biggest challenges to achieving precision medicine in allergy are characterizing allergic endotypes, understanding allergic multimorbidity relationships, contextualizing the impact of environmental exposures (the “exposome”) and ancestry/genetic risks, achieving actionable multi-omics integration, and using this information to develop adequately powered patient cohorts and refined clinical trials. In this paper, we highlight several recently developed tools and methods showing promise to realize the aspirational potential of precision medicine in allergic disease. We also outline current challenges, including exposome sampling and building the “knowledge network” with multi-omics integration.

Insights into allergic risk factors from birth cohort studies

OBJECTIVE

To present an update of birth cohort study designs and their contributions to allergic risk.

DATA SOURCES

The PubMed database was used to search for relevant articles.

STUDY SELECTIONS

Peer-reviewed prospective and retrospective studies involving the assessment of allergy using human birth cohorts between 2014 and 2021 were evaluated.

RESULTS

Parental history of allergic diseases, especially in cases involving both parents, is associated with increased risk of allergy. Exposure to prenatal and postnatal smoking and limited diet diversity were associated with increased allergic burden. The impact of early-life infections and antibiotics on disease development may be associated with the onset of asthma, though this remains debated. Cohort studies also revealed that the mode of delivery and breastfeeding duration affect the odds ratio of asthma and eczema development. Household exposures, including pets, house dust mites, and scented aeroallergens may confer protective effects, whereas high air pollution exposure and low socioeconomic status may be risk enhancing. Exposure to antibiotics during early life may be associated with increased asthma risk, whereas viral infections may lead to disease protection, though the impact of the coronavirus disease 2019 pandemic on allergic risk is yet to be understood.

CONCLUSION

Although evaluating the risk of allergic disease development is complex, clinicians can apply these insights on the multifactorial nature of atopy to better understand and potentially mitigate disease development.