Comparison of a partially hydrolyzed infant formula with two extensively hydrolyzed formulas for allergy prevention: a prospective, randomized study

Nutritional evaluation of protein hydrolysate formulas in healthy term infants: plasma amino acids, hematology, and trace elements

BACKGROUND

Protein hydrolysate formulas are used for infants with food allergy. Most studies of such formulas focus on their effect on allergy and rarely evaluate their capacity to provide normal nutritional status.

OBJECTIVE

We compared plasma aminograms, serum urea nitrogen, and trace element status in breastfed infants, infants fed hydrolysate formulas, and infants fed milk formula.

DESIGN

From 6 wk to 6 mo of age, infants were breastfed or fed regular milk formula (RF), 1 of 2 casein-hydrolysate formulas (CH-1 or CH-2), or whey-hydrolysate formula (WH). Anthropometric measures were taken monthly, and blood samples were collected at 6 wk and 6 mo. Plasma amino acids, serum urea nitrogen, hematologic indexes, plasma zinc, and plasma copper were analyzed.

RESULTS

There were no significant differences in hemoglobin, serum transferrin receptor, copper, or zinc among groups. Serum ferritin was significantly lower in infants fed the CH formulas than in the other groups. Infants fed CH-2 had significantly higher serum urea nitrogen than did all other groups. Plasma threonine, valine, phenylalanine, methionine, and tryptophan were significantly higher in the hydrolysate formula groups than in the breastfed group. Plasma tyrosine was significantly lower in infants fed the CH formulas than in the breastfed group, whereas arginine was significantly higher in the WH group than in all other groups. Plasma proline was lower, whereas threonine and tryptophan were higher, in the WH group than in the CH groups.

CONCLUSIONS

The iron status of infants fed CH formula was lower than that of all other groups. The amounts of amino acids provided by hydrolysate formulas appear excessive compared with regular formula, which is reflected by high serum urea nitrogen (CH-2) and high plasma amino acid concentrations. A reduced and more balanced amino acid content of hydrolysate formulas may be beneficial.

[An increase in allergic diseases in childhood--current hypotheses and possible prevention]

During the last few decades there has ben a significant rise in the prevalence of allergic diseases such as asthma, hay fever and atopic dermatitis. Epidemiological studies strongly suggest that this increase is real and not due to changes in diagnostic labelling. It has become increasingly clear that a complex interplay between genetic and environmental factors account for this phenomenon. Genetically predisposed individuals are at an increased susceptibility to develop asthma or other allergic diseases when exposed to certain environmental or lifestyle factors. Particularly passive smoking has been shown to increase the risk for asthma in many studies and for atopy at least in some studies. This association is less clear for the exposure to sulfur dioxide, particulate matter, diesel exhaust and ozone. Lifestyle factors like socioeconomic status, sib-ship size, early childhood infections, dietary habits, growing up in antroposophic families or on a farm are more and more realised to be of great relevance for the development of allergic conditions. At the moment, there is a lot of uncertainty about which recommendations should be given for primary prevention. Recent studies have challenged the old paradigma that avoidance of early allergen contact could prevent the development of allergic disease. However, there is consensus that avoidance of smoking during pregnancy and avoidance of passive smoking during childhood should be recommended for primary prevention of asthma.

Primary dietary prevention of food allergy

OBJECTIVE

To present research and clinical evidence on the use of primary dietary prevention in food allergy management.

DATA SOURCES

We conducted MEDLINE searches for pertinent articles published between January 1986 and October 2001 with use of the following keywords or phrases: prevention and diet and allergy, food allergy and prevention, and dietary prevention and food allergy or allergens. Also included are information and commentary reflecting the authors' cumulative clinical experience in an allergy unit of a city hospital.

RESULTS

We define as "proactive" those strategies centered on "success factors," such as the early postnatal environment, prolonged breast-feeding, and use of formula and probiotic supplementation, in contrast to earlier "prohibitionist" approaches to prevention of food allergy. These two approaches are not antagonistic and may even be synergistic. We introduce this distinction in light of epidemiologic evidence and out of concern about compliance and the quality of life for patients.

CONCLUSIONS

Inasmuch as nutritional and immune maturation are implicated, the prohibitionist measures that are most effective in primary prevention of food allergy are exclusive breast-feeding for at least 6 months (for lifelong immunity and other benefits), delayed (after the sixth month) introduction of solid foods, and on-indication use of "hypoallergenic" formulas. Whether proactive strategies can be contemplated remains a debatable issue. Evidence for and against the scientific use of probiotics as well as microbiologic, epidemiologic, and clinical data are discussed. Review of published epidemiologic studies and randomized clinical trials is essential before planning dietary intervention or prevention.

Therapeutic modalities for cow's milk allergy

OBJECTIVE

To discuss current therapeutic modalities for cow's milk allergy and its prevention.

DATA SOURCES AND STUDY SELECTION

The sources of data include original clinical studies carried out at Ste. Justine Hospital, as well as a systematic search of the published English and French language scientific literature restricted to human subjects using computerized searches (National Public Library of Medicine, Cochrane Database Systems Review) from 1997 to 2002. Search terms for article retrieval included food allergy, milk allergy, therapy, and prevention.

CONCLUSIONS

The therapy of food allergies depends upon an accurate diagnosis, which remains a challenge in non--IgE-mediated cases. Dietary exclusion remains the mainstay of therapy, with medications reserved for exceptional patients. Preliminary evidence suggests that pancreatic enzyme supplementation may be of benefit for cases with multiple food allergies and severe eczema. Hydrolysate formula use is currently recommended for dietary allergy prevention in infants at an increased risk when maternal milk is insufficient or unavailable. The use of partially hydrolyzed formulas to prevent allergic disorders, including atopic dermatitis, is supported by clinical studies, but cannot be used in the already sensitized, milk-allergic child. Probiotics show enormous potential in preventing food allergic disorders as well.

Breast-feeding, infant formulas, and the immune system

OBJECTIVE

Breast-feeding provides many advantages to the offspring, but presently there is an ongoing debate whether or not it prevents allergy any better than certain formulas. This report reviews the mechanisms involved and discusses how breast-feeding may protect against allergy.

DATA SOURCES

The review builds on an internet-based literature search in addition to our own data.

RESULTS

Human milk is the food best adapted to the needs of the offspring, also because it provides efficient protection against infections and actively stimulates the development of the infant's own immune system. The major host defense system is provided via the secretory IgA antibodies produced in the mammary glands by lymphocytes, which have migrated there from the mother's gut mucosa. Therefore, these antibodies in the milk are primarily directed against the microbes in the mother's gut and her food proteins. As a result, breast-feeding starting directly after delivery will provide an excellent defense against the microbes normally meeting the neonate and needed to induce development of its immune system. The milk also contains numerous components, which seem to enhance the infant's host defense as well as capacity to develop tolerance, helping to avoiding allergic reactivity to foods, etc.

CONCLUSIONS

Several studies show that breast-feeding prevents allergic diseases, but there are also good disagreeing studies. Supported by animal data, it seems that protection is enhanced in areas with more advantageous fat intake, inter alia lower ratio of n-6/n-3 fatty acids. Breast-feeding seems to protect against future development of allergic diseases, but possibly less so in countries with an untoward maternal fat intake.

The effect of hydrolyzed cow's milk formula for allergy prevention in the first year of life: the German Infant Nutritional Intervention Study, a randomized double-blind trial

BACKGROUND

The potential of extensively or partially hydrolyzed formulas to reduce the risks for allergies is controversial.

OBJECTIVE

We sought to assess the preventive effect of differently hydrolyzed formulas compared with cow's milk formula (CMF) in high-risk infants.

METHODS

Between 1995 and 1998, 2252 infants with a hereditary risk for atopy were enrolled in the German Infant Nutritional Intervention Study and randomly assigned at birth to one of 4 blinded formulas: CMF, partially hydrolyzed whey formula, extensively hydrolyzed whey formula, and extensively hydrolyzed casein formula (eHF-C). The primary end point at 1 year of age was the presence of allergic manifestation, which was defined as atopic dermatitis (AD), gastrointestinal manifestation of food allergy, allergic urticaria, or a combination of these factors.

RESULTS

At 12 months per protocol, analysis was performed on 945 infants exposed to study formula: 304 (13.5%) infants had left the study, 138 (6.1%) infants were excluded because of noncompliance, and 865 infants were exclusively breast-fed the first 4 months of life. The incidence of allergic manifestation was significantly reduced by using eHF-C compared with CMF (9% vs 16%; adjusted OR, 0.51; 95% CI, 0.28-0.92), and the incidence of AD was significantly reduced by using eHF-C (OR, 0.42; 95% CI, 0.22-0.79) and partially hydrolyzed whey formula (OR, 0.56; 95% CI, 0.32-0.99). Family history of AD was a significant risk factor and modified the preventive effect of the hydrolysates.

CONCLUSIONS

Prevention of allergic diseases in the first year of life is feasible by means of dietary intervention but influenced by family history of AD. The preventive effect of each hydrolyzed formula needs to be clinically evaluated.

Cost of illness of atopic dermatitis in children: a societal perspective

Childhood atopic dermatitis is a disorder with considerable social and financial costs. Consideration of these costs is increasingly important in view of the growing prevalence of atopic dermatitis, particularly in developed countries over recent decades. The family stress related to the care of children with moderate or severe atopic dermatitis is significantly greater than that of the care of children with type 1 diabetes mellitus. The factors contributing to family stress include sleep deprivation, loss of employment, time taken for care of atopic dermatitis and financial costs. The financial costs for the family and community include medical and hospital direct costs of treatments and indirect costs from loss of employment. There are many interventions utilised in the treatment of childhood atopic dermatitis which involve not only medical practitioners but nurses, pharmacists, dieticians, psychologists and purveyors of so-called alternative therapies such as naturopathy, aromatherapy and bioresonance, all of which contribute to the financial burdens on the parents and the community. It is possible that appropriate interventions directed to reducing trigger factors might produce worthwhile savings, although the cost benefit of these measures has not been demonstrated. In conclusion, atopic dermatitis should not be regarded as a minor skin disorder but as a condition which has the potential to be a major handicap with considerable personal, social and financial consequences both to the family and the community.

Effect of exclusive breast-feeding and early solid food avoidance on the incidence of atopic dermatitis in high-risk infants at 1 year of age

The aim of this study was to assess the preventive effect of exclusive breast-feeding and early solid food avoidance on atopic dermatitis (AD) in infancy. This study is part of a dietary clinical trial in a prospective cohort of healthy term newborns at risk of atopy. It was recommended to breast-feed for at least 4 months and to avoid solid food in the same time-period. Eight hundred and sixty-five infants exclusively breast-fed, and 256 infants partially or exclusively formula-fed, were followed-up until the end of the first year following birth. AD and sensitization to milk and egg were considered as study end-points. The 1-year incidence of AD was compared between the two study groups. Adjusted odds ratios (OR) with 95% confidence intervals (CI) were calculated by multiple logistic regression. The incidence of AD was calculated in relation to age at introduction of solid food and amount of food given. In the breast-fed group, the adjusted OR for AD was 0.47 (95% CI 0.30-0.74). The strongest risk factor was the occurrence of AD in the subject's core family. The risk of infants with AD to be sensitized to milk was four times higher, and to egg eight times higher, than in infants without AD. Age at first introduction of solid food and diversity of solid food showed no effect on AD incidence. We conclude that in infants at atopic risk, exclusive breast-feeding for at least 4 months is effective in preventing AD in the first year of life.

Cow's milk allergy in infancy

Cow's milk allergy affects approximately 2% of infants under 2 years of age. This review summarizes the recent advances in understanding its pathophysiology and immunological mechanisms. Apart from IgE-mediated atopic manifestations, T cell-mediated reactions have been demonstrated in infants with cow's milk allergy. The clinical spectrum ranges from immediate-type reactions, presenting with urticaria and angioedema to intermediate and late-onset reactions, including atopic dermatitis, infantile colic, gastro-oesophageal reflux, oesophagitis, infantile proctocolitis, food-associated enterocolitis and constipation. The exact mechanisms of these disorders are still poorly understood. Double-blind, placebo controlled food challenge, the definitive diagnostic test for cow's milk allergy, is increasingly being replaced by the measurement of food-specific antibodies, in combination with skin-prick or atopy patch testing. The treatment of cow's milk allergy relies on allergen avoidance and hypoallergenic formulae, or maternal elimination diets in breast-fed infants.

Food allergy

Allergic disease is a major contributor to illnesses and mortality worldwide. Food hypersensitivity is often the first phenomenon in the allergic march that includes gastroenteropathy, eczema, asthma and hay fever. Recent evidence indicates that prevention of food hypersensitivity in early life is associated with reduction in the incidence of eczema and asthma in later childhood. Strategies for prevention include exclusive breast feeding, restriction of mother's diet during lactation, hydrolyzed formula, delayed introduction of allergenic solid foods and reduced exposure to house dust mites and tobacco smoke. This is a highly cost-beneficial and cost-effective approach.

Cow's milk protein avoidance and development of childhood wheeze in children with a family history of atopy

BACKGROUND

In infants with a family history of atopy, food allergen avoidance has been advocated as means of preventing the development of atopic disease when breast-feeding is not possible or supplemental feeding is needed. Most infant formulas are based on cow's milk protein. Alternative choices include soya based and hydrolysed cows milk formulas.

OBJECTIVES

To estimate the effect of dietary avoidance of cow's milk protein on the development of asthma or wheeze in children.

SEARCH STRATEGY

The Cochrane database was searched for eligible trials until February 2002. The full text papers of all abstracts identified as RCTs were obtained and reviewed independently by two reviewers.

SELECTION CRITERIA

Randomised controlled trials involving children with a family history of atopy in at least one first degree relative were considered if feeding with cow's milk based standard formula was compared to dietary avoidance of cow's milk protein using soya or other hypoallergenic formula during the initial four months of life or longer.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data independently. A priori defined subgroups were the types of hypoallergenic artificial feed and dietary restrictions on mother and/or child's diet.

MAIN RESULTS

Six trials used hydrolysed formula for at least 4 months in addition to dietary restrictions and in some cases dust-mite reduction measures. The risk of infants experiencing asthma or wheeze during the first year of life was reduced compared to standard cow's milk based formula (Relative Risk =0.40, 95% Confidence Intervals 0.19, 0.85). Feeding soya-based formula as opposed to standard cow's milk formula did not reduce the risk of having asthma or wheeze at any age.

REVIEWER'S CONCLUSIONS

Breast-milk should remain the feed of choice for all babies. In infants with at least one first degree relative with atopy, hydrolysed formula for a minimum of 4 months combined with dietary restrictions and environment measures may reduce the risk of developing asthma or wheeze in the first year of life. There is insufficient evidence to suggest that soya-based milk formula has any benefit.

Treatment principles of atopic dermatitis

Atopic dermatitis (AD) is today the most common, chronic inflammatory skin disease among children in developed countries. Its cumulative prevalence varies from 20% in northern Europe and the USA to approximately 5% in Mediterranean countries. As a chronic disease it puts a special demand on treatment. There is no curative therapy, but competent guidance on treatment principles can control the disease in most, if not all children. This article summarizes the evidence-based knowledge that relates to the treatment of atopic eczema. It also gives advice and opinions on prophylactic measures as these are the focus of interest from most parents.

LEARNING OBJECTIVE

This article should enable you to give advice and guidance to parents of children with AD, including what is necessary for diagnosis, what is of value and importance considering allergies and allergological investigations, allergen exposure, prophylactic measures, diets and indoor environment. Finally, you should be able to explain the diversity of treatment principles for parents.

Cow's milk-specific cellular and humoral immune responses and atopy skin symptoms in infants from atopic families fed a partially (pHF) or extensively (eHF) hydrolyzed infant formula

BACKGROUND

Hydrolyzed milk formulas are recommended to feed infants at high risk of atopy if breast-feeding is not possible. We studied the specific cellular and humoral immune response to cow's milk proteins and occurrence of atopic dermatitis under different feeding regimens: two hydrolyzed infant milk formulas (partially [pHF] and extensively hydrolyzed [eHF]) and under exclusive breast-feeding (BF).

METHODS

Seventy-two infants from families with atopic symptoms were randomized in the pHF and eHF groups, respectively. At 6 and 12 months of age, peripheral blood mononuclear cell proliferation along with specific IgG and IgE to cow's milk proteins was determined in infants fed pHF or eHF, respectively, and those who had not yet received any formula at 6 months of age (BF). Cases of atopic dermatitis were recorded throughout the first 12 months of life, and their severity was evaluated with SCORAD points.

RESULTS

A significantly decreased proliferation to cow's milk caseins was found in the pHF group compared to the exclusively breast-fed group. Medians of stimulation indexes for CAS at 6 months were as follows: pHF 1.18; n=24; BF 1.70; n=24 (P=0.033, Mann-Whitney U-test). Higher levels of plasma IgG antibodies to BCAS were found in infants fed pHF than in those fed eHF at 12 months. Optical density (OD): (25th percentile; median; 75th percentile): pHF: 0.00; 0.14; 0.38; n=30; eHF: 0.00; 0.03; 0.14; n=28; P=0,089, Mann-Whitney U-test. Cow's milk-specific IgE was detected at 6 months as follows: BF: 3 of 24; eHF: 2 of 21; pHF: 0 of 23. The number of cases of atopic dermatitis and their severity did not differ among the groups during the first 12 months.

CONCLUSIONS

Feeding pHF appears to suppress cow's milk-specific cellular responses and stimulate specific IgG production. Specific IgE sensitization can occur also with breast-feeding.

Food allergen avoidance in primary prevention of food allergy

Approximately 5-10% of children suffer from allergy to one or more foods. Primary prevention through a hypoallergenic diet may reduce the prevalence of food allergy and associated co-morbidity, such as eczema and urticaria. Breastfeeding has many advantages and should be recommended for all children. Those with a history of atopy in the immediate family are at a higher risk and maternal diet during lactation, avoiding highly allergenic foods, may enhance the benefit. Cow's milk should be strictly avoided, and supplements, if required, should be with a hypoallergenic formula. Delayed introduction of egg, nuts, wheat and fish has also been suggested. Dietary restriction may have nutritional consequences for the mother and child and supervision by a dietician is essential. Maternal diet during pregnancy is not advisable as the benefit is minimal and there may be adverse effects on the foetal nutrition. In high risk infants, a combined approach, where breastfeeding with maternal avoidance of highly allergenic foods, supplemented by extensively hydrolysed formula during the first 6 months of life, in addition to the delayed introduction of solid foods, has been shown to reduce the development of food allergy in infants.