“Planetary science” – just esoteric blahblah? Embracing the whole world? Exposome instead of enviromental exposure? The desperate reaction to many unresolved questions?

The importance of the exposome and allostatic load in the planetary health paradigm.
Logan AC, Prescott SL, Haahtela T, Katz DL.
In 1980, Jonas Salk encouraged professionals in anthropology and related disciplines to consider the interconnections between “planetary health,” sociocultural changes associated with technological advances, and the biology of human health. The concept of planetary health emphasizes that human health is intricately connected to the health of natural systems within the Earth’s biosphere; experts in physiological anthropology have illuminated some of the mechanisms by which experiences in natural environments (or the built environment) can promote or detract from health. For example, shinrin-yoku and related research (which first emerged from Japan in the 1990s) helped set in motion international studies that have since examined physiological responses to time spent in natural and/or urban environments. However, in order to advance such findings into planetary health discourse, it will be necessary to further understand how these biological responses (inflammation and the collective of allostatic load) are connected to psychological constructs such as nature relatedness, and pro-social/environmental attitudes and behaviors. The exposome refers to total environmental exposures-detrimental and beneficial-that can help predict biological responses of the organism to environment over time. Advances in “omics” techniques-metagenomics, proteomics, metabolomics-and systems biology are allowing researchers to gain unprecedented insight into the physiological ramifications of human behavior. Objective markers of stress physiology and microbiome research may help illuminate the personal, public, and planetary health consequences of “extinction of experience.” At the same time, planetary health as an emerging multidisciplinary concept will be strengthened by input from the perspectives of physiological anthropology.

There is an update of our eosinophil SNP paper now in the Lancet with 27 new asthma CpG associations. The authors claim 3 overlaps to Cookson’s  36 IgE loci while I see only cpg0177040, maybe there are two more conicidental findings in the supplement? At least the paper says

eosinophil counts were not significantly different between patients with asthma and controls in our discovery cohorts, suggesting that our results reflect the presence of a different subset or activation state of eosinophils, rather than a change in eosinophil counts per se. Although eosinophils are linked to sub-phenotypes of asthma such as the T helper 2-type subset, our study provides unequivocal data supporting their involvement at the epigenetic level in mild-to-moderate asthma in children.

maybe, maybe not – this could be just residual confounding…

Additionally, CpG methylation patterns identified an early-life shift from naive T cell populations towards effector and memory CD8 and natural killer cell subsets, indicating a potentially crucial role for host virus interactions

maybe, maybe not – this could be vaccine effects, some other antigens, allergens or vitamin D

A new analysis of the GINI-LISA study published this month in Pediatr Allergy Immunol has an interesting plot showing the eczema incidence in the first 15 years of life. Eczema is a major allergy symptom.

On the right side (FIG1C), we find the untreated group, and on the left (FIG1A) we find the intervention group. Overlying both figures with Photoshop gives an interesting perspective.

When we use the lower opaque double line as reference, all types of baby feeding  give an increased eczema risk. To be more comparable, the opaque upper two lines should be used, which will result in zero effect size.

The question is: Why is breast feeding / breast milk (BF) a risk factor in the interventional (left figure)  but not in the observational arm (right figure)?

1. In accordance with national and international guidelines full BF was recommended for 4 months in the interventional group. “Only in case of insufficient BF, children were randomized to one of the baby foods”. “Insufficient BF” is not clearly defined and the reasons seem to be complex.
2. The general pediatric recommendation at the time of the study was that BF is allergy-preventive and that allergic children should be BF as long as possible.
3. BF in the interventional arm therefore is a self-selected biased group primarily by allergic mothers and children with unclear criteria. The authors acknowledge in the discussion “Even adjustment for the potential confounders does not eliminate the phenomenon of reverse causality. Particular early eczema occurring in the first months of life may influence the mother’s decision regarding full breastfeeding versus formula supplementation.”
4. BF is a complex chemical mixture that even varies over time – there is is a long-standing controversy on the effect of BF on allergy  with many negative, null and positive associations to allergy. From this discussion we can assume, that there is probably no direct effect of BF on allergy development. More likely BF is a proxy for something else – setting up a further biological argument that the interventional BF group should NOT be used as a  reference.

Children who receive “antiallergic” formula food will not have any benefit which is in accordance with a recent review in the BMJ. Nevertheless Nestlé Beba Pro HA is further advertising as “reducing allergy risk to milk protein”, Hipp HA Combobiotik as “reducing allergy risk by strong protein cleavage”, Nutramigen 1 LGG as “extensively hydrolysed, hypoallergenic formula … suitable for babies with … allergy”.

Postscriptum

The revised blog entry has been published as a letter to PAI. Unfortunately it turned out only after submission that there are also some major issues with the number of individuals included when comparing the 2003 with the 2013 and 2018 report.