Moving house or the separation of parents
can significantly increase the risk of children developing
allergies later on. These are the results from a long-term
study correlating life-style, immune system development
and allergies, led by the Helmholtz Center for Environmental
Research in Leipzig (UFZ), the Helmholtz Zentrum München
and the "Institut für Umweltmedizinische Forschung"
(IUF) in Duesseldorf.
The researchers had examined blood samples taken from
234 six-year old children and discovered increased blood
concentrations of the stress-related peptide VIP (vasoactive
intestinal polypeptide) in connection with moving house
or the separation of parents. The neuropeptide VIP could
take on a mediator role between stress events in life
and the regulation of immune responses, researchers
write in the scientific journal Pediatric Allergy and
Immunology. The fact that stress events can have an
influence on the development of allergies has been known
for a while. The mechanisms behind this however remained
unexplained for a long time. In the study that has now
been published, stress events were investigated for
the first time during early childhood within a large
epidemiological study using immune and stress markers.
Stress events during childhood are increasingly suspected
of playing a role in the later development of asthma,
allergic skin disorders, or allergic sensitisations.
Dramatic life events like the death of a family member,
serious illnesses of a family member or the separation
of parents, but also harmless events like for example
moving house are suspected of increasing the risk of
allergies for the children affected. The immune system
obviously plays a mediator role between stress on the
one hand and allergies on the other. Since these mechanisms
had hardly been understood before, researchers attempted
to identify stress-related factors showing an influence
on the immune system, in the context of an epidemiological
study (LISA). At the same time as the blood tests, researchers
together with colleagues from the Institute for Social
Medicine at the University of Lübeck also analysed the
most diverse social factors in the children’s
environment, in order to find out which factors are
causing stress-related regulation deficiencies of the
immune system. With children, whose parents had separated
over the last year, researchers found increased blood
concentrations of the neuropeptide VIP (vasoactive intestinal
polypeptide) as well as an increased concentration of
immune markers, which are related to the occurrence
of allergic reactions, like for example the cytokine
IL-4. By comparison, serious diseases or the death of
close relatives led to no remarkable changes. Likewise,
the unemployment of parents was not associated with
increased concentrations of the stress-related peptides
in the children’s blood.
As tragic as these events are, they are obviously however
of less significance for the stress reactions of children
than for example a separation or the divorce of parents,
UFZ researchers have concluded. As was already shown
in an earlier publication from the same study, increased
concentrations of the stress peptide VIP can also be
proven in the blood of children after moving house (similar
to the separation of parents). Preceding investigations
in LISA showed that there is a relationship between
an increased concentration of the neuropeptide VIP and
allergic sensitisations among six-year old children.
Even if the results were to be interpreted carefully,
because of the comparatively small number of children
affected, they nevertheless provide valuable indications
as to what exactly happens to the body through stress.
The investigations are based on data from 6-year old
children from the LISA study. LISA stands for "Lifestyle
- Immune System - Allergy" and investigates the influences
of lifestyles on the immune system development in early
childhood and the emergence of allergies. In addition
to the Helmholtz Center for Environmental Research in
Leipzig (UFZ), the Helmholtz Zentrum München, the German
Research Center for Environmental Health, and the "Institut
für Umweltmedizinische Forschung" (IUF) in Duesseldorf,
other universities and clinics are also participating
partners, including the Municipal Hospital "St. Georg"
in Leipzig. For the LISA study over 3000 newborn children
in the cities of Munich, Leipzig, Wesel and Bad Honnef
were recruited between the end of 1997 and the beginning
of 1999. Parents were repeatedly asked about various
lifestyle-related factors and disease outcomes. Furthermore,
blood tests were carried out at different times. At
the age of six a total of 565 children were examined
in Leipzig, and for 234 participants, blood analyses
regarding stress and immune parameters were carried
out. Over the course of the 6-year study nearly one
third of the families living in Leipzig were affected
by unemployment. For approximately half of all families,
severe illnesses were experienced by close family members.
By comparison, cases of death among family members or
the separation of parents only affected every sixth
or tenth child.
