Breastfeeding attenuates reductions in energy intake induced by a mild immunologic stimulus represented by DPTH immunization: possible roles of interleukin-1beta, tumor necrosis factor-alpha and leptin

Low-dose Thimerosal (ethyl-mercury) is still used in infants` vaccines: Should we be concerned with this form of exposure?

In developing countries, Thimerosal-containing vaccines (TCV) are the main causes of organic Hg exposure for newborns, neonates, and infants immunized with TCV. This article addresses early-life exposure to this unique organic mercury compound (ethylmercury-EtHg) and the risks of its exposure. English language studies pertaining to Thimerosal/EtHg toxicity and exposure during early life were searched in PubMed; and, those publications judged to be relevant to the topic of this review were selected. The risk from the neurotoxic effects of pre- and post-natal Hg exposures depend, in part, on aggravating or attenuating environmental and/or genetic-associated factors. Health authorities in charge of controlling infectious disease dismiss the toxicology of mercury (immunological and subtle neurological effects as insignificant) related to low-dose Thimerosal. The review addresses the evidence that brings into question the safety of Thimerosal that is still present in vaccines given to pregnant women, infants, and children in developing countries, and recognizes the ethical imperative to extend the use of Thimerosal-free vaccines to developing countries, not just developed countries.

Exposure to mercury and aluminum in early life: developmental vulnerability as a modifying factor in neurologic and immunologic effects

Currently, ethylmercury (EtHg) and adjuvant-Al are the dominating interventional exposures encountered by fetuses, newborns, and infants due to immunization with Thimerosal-containing vaccines (TCVs). Despite their long use as active agents of medicines and fungicides, the safety levels of these substances have never been determined, either for animals or for adult humans—much less for fetuses, newborns, infants, and children. I reviewed the literature for papers reporting on outcomes associated with (a) multiple exposures and metabolism of EtHg and Al during early life; (b) physiological and metabolic characteristics of newborns, neonates, and infants relevant to xenobiotic exposure and effects; (c) neurobehavioral, immunological, and inflammatory reactions to Thimerosal and Al-adjuvants resulting from TCV exposure in infancy. Immunological and neurobehavioral effects of Thimerosal-EtHg and Al-adjuvants are not extraordinary; rather, these effects are easily detected in high and low income countries, with co-exposure to methylmercury (MeHg) or other neurotoxicants. Rigorous and replicable studies (in different animal species) have shown evidence of EtHg and Al toxicities. More research attention has been given to EtHg and findings have showed a solid link with neurotoxic effects in humans; however, the potential synergic effect of both toxic agents has not been properly studied. Therefore, early life exposure to both EtHg and Al deserves due consideration.

Protective effect of exclusive breastfeeding against hand, foot and mouth disease

BACKGROUND

Infants who are exclusively breastfed receive natural protection against some infectious agents. This study examined whether there was protective effect of exclusive breastfeeding on the occurrence of hand, foot and mouth disease, which was an emerging infectious disease among children in China.

METHODS

A community-based case-control study was carried out among children age 4 years or younger in Guangdong Province, China. Cases were newly diagnosed hand, foot and mouth disease. Controls were randomly sampled from healthy children from the nearby village. Unconditional logistic regression model was used to estimate the odds ratio (OR) for exclusive breastfeeding after adjusting for potential confounding factors.

RESULTS

A total of 316 cases and 566 controls were included in the analysis. Significantly beneficial effect of exclusive breastfeeding during the first 6 months was observed for hand, foot and mouth disease occurrence. The overall OR was 0.63 (95% CI: 0.47-0.85) for exclusive breastfeeding compared with mixed feeding type. The age-specific analyses indicated that the protective effect persisted till the age of 28 months.

CONCLUSIONS

This study suggests that exclusive breastfeeding might have protective effect against HFMD infection among the children within 28 months of age.

Effect of breastfeeding on serum osteoprotegerin and soluble receptor activator of nuclear factor-kappa B ligand in full term neonates

Background

Human breast milk, the sole source of nutrition during the early neonatal period, is rich in nutrients, hormones, growth factors, and immunoactive molecules, which influence the growth, development, and immune status of the newborn infant. It had long been thought that breast milk is an adequate source of anthracitic activity for the newborns and growing child.

Objective

Human milk is a complex biologic fluid which contains nutritional and protective factors such as Osteoprotegerin (OPG), at levels 1000-fold higher than normal human serum. Since OPG and Receptor activator of nuclear factor-kappa B ligand (RANKL) system are tightly involved in bone remodeling and immune activity, the study was designated to evaluate the effect of breastfeeding on serum soluble receptor activator of nuclear factor-kappa B ligand (sRANKL) /OPG ratio in full term neonates in comparison with those of formula feeding full term neonates.

Materials and Methods

In this cross-sectional study serum levels of OPG and sRANKL in 45 breastfed infants were compared to those of 44 formula-fed full term infants. The levels of serum OPG, sRANKL, and Tumor necrosis factor alpha (TNFα) were determined by standard techniques using enzyme-linked immunosorbent assay kits.

Results

The serum levels of OPG were significantly higher (P < 0.001), and the concentrations of TNFα was markedly lower (P = 0.024) in breastfed infants than those of formula-fed infants. No marked differences were observed between the serum levels of sRANKL in the two study groups (P = 0.8).

Conclusions

High OPG and low TNFα levels in serum of breastfed infants are important factors involved in remodeling of bone, and immune activity may prove superiority of breastfeeding over formula feeding during infancy.

Prolonged exclusive breastfeeding, autumn birth and increased gestational age are associated with lower risk of fever in children with hand, foot, and mouth disease

Epidemics of hand, foot, and mouth disease (HFMD) have been emerging and reemerging in recent years. This study aims to investigate whether breastfeeding and other factors may affect the profile of fever and disease course in children with HFMD. Three hundred seventy-two preschool children with HFMD were included. The demographics, environmental factors, and delivery- and feeding-associated factors in the children were obtained and their effects on the profile of fever and disease course were analyzed. Of the 372 children, 139 (37.37%) had fever during the disease course. Gender, breastfeeding pattern, birth season and gestational age were significantly different between the children with and without fever (p = 0.034, p < 0.0001, p = 0.035 and p = 0.013, respectively). After multivariate-adjusted analysis, prolonged exclusive breastfeeding (p = 0.001, OR 0.401, 95% CI 0.229-0.704), autumn birth (p = 0.007, OR 0.409, 95% CI 0.214-0.784) and higher gestational age (p = 0.029, OR 0.089, 95% CI 0.010-0.781) were protective factors for the incidence of fever.

Breastfeeding and risk for fever after immunization

OBJECTIVE

The objective of this study was to evaluate the effects of breastfeeding on the risk for fever after routine immunizations.

METHODS

A prospective cohort study was conducted at a pediatric vaccination center in Naples, Italy. The mothers of the infants scheduled to receive routine immunizations were instructed on how to measure and record infant temperature on the evening of the vaccination and for the subsequent 3 days. The information about the incidence of fever was obtained by telephone on the third day after vaccination. The relative risk for fever in relation to the type of breastfeeding was estimated in multivariate analyses that adjusted for vaccine dose, maternal education and smoking, and number of other children in the household.

RESULTS

A total of 460 infants were recruited, and information on the outcome was obtained for 450 (98%). Fever was reported for 30 (25%), 48 (31%), and 94 (53%) of the infants who were being exclusively breastfed, partially breastfed, or not breastfed at all, respectively (P < .01). The relative risk for fever among infants who were exclusively and partially breastfed was 0.46 (95% confidence interval: 0.33-0.66) and 0.58 (95% confidence interval: 0.44-0.77), respectively. The protection conferred by breastfeeding persisted even when considering the role of several potential confounders.

CONCLUSIONS

In this study, breastfeeding was associated with a decreased incidence of fever after immunizations.

Breastfeeding is an essential complement to vaccination

AIM

This article explores the role of breastfeeding in different aspects of vaccination in the first 6 months when infants are still developing: (1) pain management; (2) immunomodulation of infants' vaccine responses; (3) metabolism of thimerosal.

METHODS

Major databases were searched for studies that addressed outcomes of related issues.

RESULTS

Studies reveal that breastfeeding can: (1) help mothers and infants to cope with the stressful situations that accompany parenteral vaccines; (2) improve response to vaccines in the still maturing immunologic and enterohepatic systems of infants; (3) influence physiologic parameters that can change metabolism of ethylmercury derived from some vaccines.

CONCLUSION

Health promotion that supports vaccinations should also emphasize early initiation and maintenance of exclusive breastfeeding up until 6 months for maximum protection of the infants with a possible beneficial effect on the vaccine response. Paediatric professionals should inform mothers of the proven benefits of breastfeeding and its importance in complementing vaccination and lowering stress and the risk of untoward reactions on susceptible infants.

Breastfeeding's protection against illness-induced anorexia is mediated partially by docosahexaenoic acid

OBJECTIVE

To test whether breastfeeding's protection against anorectic responses to infection is mediated by n-3 fatty acids' attenuation of interleukin (IL)-1beta and tumor necrosis factor (TNF)alpha.

DESIGN

Experimental and observational studies.

SETTING

A hospital-based study was conducted.

SUBJECTS

Five groups of infants were followed; three in the experimental and two in the observational study.

METHODS

Breast-fed- (BF-1), DHA-supplemented formula- (SFF-1), and non-DHA-supplemented formula-fed (FF-1) infants were studied before and after immunization against diphtheria, tetanus, pertussis and haemophilus influenzae type b. Pre- and post-immunization energy intakes (EI) and serum IL-1beta and TNFalpha were measured. The two other groups, breast-fed (BF-2) and formula-fed (FF-2) infants with pneumonia were followed throughout hospitalization. EI, IL-1beta and TNFalpha were measured at admission and discharge. Baseline erythrocyte fatty acid contents were determined.

RESULTS

Both cytokines increased following immunization in all feeding groups. Post-immunization reductions in EI of SFF-1 infants (-11.8+/-5%, CI(95)=-23.3, 1.4%, P=0.07) were intermediate to those observed in BF-1 (-5.2+/-4.2%, CI(95)=-15.2, 5.9%, P=0.27) and FF-1 infants (-18+/-4.4%, CI(95)=-29%, -5.4%, P=0.02). In the observational study, TNFalpha (17.2+/-8.3 vs 3.4+/-3.0 ng/l, P=0.001) and decreases in EI (-31+/-43 vs -15+/-31%, CI(95)=-34%, 0.001%, P=0.056) were greater in FF-2 than in BF-2 infants at admission. Breastfeeding duration was associated positively with docosahexaenoic acid (DHA) erythrocyte contents, and negatively with admission TNFalpha. Decreases in EIs were associated with IL-1beta and TNFalpha concentrations.

CONCLUSION

Reductions in EI following immunologic or infectious stimuli were associated with increases in IL-1beta and TNFalpha. Those reductions were attenuated by breastfeeding, and mediated in part by tissue DHA.

Risk factors for overweight among Brazilian adolescents of low-income families: a case-control study

OBJECTIVE

To study risk factors for overweight among Brazilian adolescents of low-income families.

DESIGN

Case-control study of obese and non-obese adolescents.

SETTING

Anthropometric survey including 1420 students (aged 14-19 years) attending a public high school in São Paulo, Brazil.

METHODS

Selection of 83 overweight (body mass index (BMI) >85th percentile) and 89 non-overweight (BMI >5th percentile and <85th percentile) subjects, frequency-matched by age, gender, pubertal development and socio-economic status. Among the nutritional, familial and behavioural data available, five covariates (parents' obesity, adolescents' past obesity, to have a best friend, dietary restriction and habit of napping) were included in the fitted hierarchical conditional logistic regression models.

MEASUREMENTS

Parents or guardians and adolescents were weighed, measured and answered a pre-tested questionnaire applied by trained nutritionists and paediatricians.

RESULTS

The prevalence of overweight was 15.2%. As previous risks, obese parents and obesity during infancy presented odds ratios (OR) and 95% confidence intervals (CI) of 2.23 (1.15-4.35) and 3.60 (1.47-8.80), respectively. As concurrent factors, the habit of napping, to have a best friend and reported dietary restriction presented OR (95% CI) of 3.43 (1.32-8.92), 5.15 (1.76-15.07) and 7.26 (2.95-17.88), respectively. Dietary patterns, frequency of obesogenic foods and other physical activity indicators presented no statistical significance.

CONCLUSION

In case-control studies, OR may overestimate the true risks. Parents' obesity and previous childhood obesity were identified as risk factors; therefore these factors should be the target for preventive programmes and policies in order to prevent the burden of obesity in the near future.

Neonatal leptin levels are strongly associated with female gender, birth length, IGF-I levels and formula feeding

OBJECTIVE

To investigate predictors of circulating leptin in healthy full-term newborns and to explore the relationship with anthropometric variables, serum levels of adiponectin and the major components of the IGF system at birth. To explore whether leptin levels are regulated by breastfeeding vs. formula feeding.

DESIGN

Observational cross-sectional study.

PATIENTS

Three hundred and nineteen healthy full-term newborns delivered during 1999 in Athens, Greece.

MEASUREMENTS

Anthropometric measurements, formula feeding information and blood samples were obtained. Leptin and adiponectin determinations were performed using a radioimmunoassay (RIA).

RESULTS

Multivariate regression analyses showed that leptin levels were positively associated with female gender, newborn length, ponderal index and IGF-I levels, but not with adiponectin levels. Newborns who were fed exclusively with milk formulas had more than twice the leptin levels of those who were exclusively breastfed.

CONCLUSIONS

Leptin levels are positively related to female gender and anthropometric characteristics of neonates but, contrary to studies in adults, are not correlated with adiponectin levels. We also found evidence that formula feeding imparts a considerable increase in leptin levels in newborns.