CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 9, October 2012
AFRICA
505
non-invasive characterisation of chronic disease risk in children,
together with other salivary biomarkers (e.g. cortisol,
α
-
amylase,
dehydroepiandrosterone) and BMI, CRF and percentage body fat.
There are a number of limitations that may have influenced
the salivary CRP measurements in our study. Although salivary
flow rate was controlled for, blood contamination, saliva pH, and
health condition of the children’s gums were not determined using
standardised methods. Specifically, a competitive immunoassay
to quantify the presence of transferrin should be used to
determine blood contamination of saliva,
7
while saliva pH should
be determined using calibrators with a known pH.
7
It is possible
that the determination of salivary CRP could be contaminated by
small blood leakages or crevicular fluid overflow due to micro-
injuries or in participants with poor oral health, as well as local
inflammatory processes, which may elevate salivary CRP levels.
7
However, in an attempt to reduce the impact of these
confounding variables, clear instructions were provided to the
parents as well as the participants regarding brushing teeth as
well as dietary and hydration practices prior to saliva collection.
It is recommended that future studies should include a complete
oral health examination as part of the participant’s health
assessment to eliminate the possibility that bucco-dental features
trigger high CRP levels in saliva in the absence of elevations in
the serum.
7
Related to the issue of oral health in the children and the possible
existence of periodontitis, a link was recently found between
periodontitis, systemic inflammation and CVD.
28
Specifically,
it was found that intensive periodontal therapy reduced local as
well as systemic reductions in inflammation, which correlated
with an improvement in endothelial functioning.
28
This finding
suggests that children with a high CRF and normal weight may
still have elevated serum/salivary CRP levels (systemic/local
inflammation) and be at risk for developing chronic disease, if
they have poor oral health.
Conclusion
The study provides initial support for a possible association
between poor CRF and/or overweight/obesity and inflammatory
status in children, based on elevated salivary CRP levels. Saliva
sampling is non-invasive, stress-free, can easily be performed
in a participant’s natural setting and can be repeated over time.
Furthermore, saliva collection has considerable economic and
logistic advantages over venipuncture because it does not require
immediate manipulations, access to specialised laboratory
equipment and qualified personnel.
Replication of the study with larger samples is required
together with longitudinal follow up of clinical outcomes.
This may contribute to a better understanding of the pathways
mediating the development and treatment of inflammation and
chronic disease in children and subsequently adults.
The authors thank Miss Melissa Naidoo for her technical assistance.
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