Prolonged and Exclusive Breastfeeding Reduces the Risk of Infectious Diseases in Infancy Association between breast feeding and asthma in 6 year old children: findings of a prospective birth cohort study Prospective study of breast-feeding in relation to wheeze, atopy, and bronchial hyperresponsiveness in the Avon Longitudinal Study of Parents and Children (ALSPAC). Asthma medication use in infancy: determinants related to prescription of drug therapy. [Prevalence of wheezing in the chest among adults from the 1982 Pelotas birth cohort, Southern Brazil]. Relationship of infant feeding to recurrent wheezing at age 6 years. Breastfeeding protects against adverse respiratory outcomes at 15 months of age. International study of wheezing in infants: risk factors in affluent and non-affluent countries during the first year of life. Ratio of Omega‐6 to Omega‐3 Fatty Acids and Childhood Asthma Effect of breastfeeding on asthma, lung function and bronchial hyperreactivity in ISAAC Phase II Nutritional errors in the first months of life and their association with asthma and atopy in preschool children. Differential effects of risk factors on infant wheeze and atopic dermatitis emphasize a different etiology. The effects of respiratory infections, atopy, and breastfeeding on childhood asthma The association of prolonged breastfeeding and allergic disease in poor urban children Asthma and infant diet. Maternal recall of breastfeeding duration twenty years after delivery Early allergen exposure, skin prick responses, and atopic wheeze at age 5 in English children: a cohort study Factors influencing the relation of infant feeding to asthma and recurrent wheeze in childhood Infant feeding and allergy. Global analysis of breast feeding and risk of symptoms of asthma, rhinoconjunctivitis and eczema in 6-7 year old children: ISAAC Phase Three. A parent-completed respiratory questionnaire for 1-year-old children: repeatability Recurrent wheezing in relation to environmental risk factors in infancy Breastfeeding and the risk of wheeze and asthma in Japanese infants: the Osaka Maternal and Child Health Study. Day-care attendance, position in sibship, and early childhood wheezing: a population-based birth cohort study. Differences between infants and adults in the social aetiology of wheeze. The ALSPAC Study Team. Avon Longitudinal Study of Pregnancy and Childhood. Breast-feeding and atopic disease: a cohort study from childhood to middle age. Promotion of Breastfeeding Intervention Trial (PROBIT): a randomized trial in the Republic of Belarus. Effect of breastfeeding on lung function in childhood and modulation by maternal asthma and atopy. Predictors for wheezing phenotypes in the first decade of life. Breast feeding and allergic diseases in infants—a prospective birth cohort study Neonatal Antibiotic Treatment Is a Risk Factor for Early Wheezing Language bias in randomised controlled trials published in English and German Are all wheezing disorders in very young (preschool) children increasing in prevalence? Exposure to maternal smoking in the first year of life interferes in breast-feeding protective effect against the onset of respiratory allergy from birth to 5 yr.
OBJECTIVE : To examine the associations of duration of exclusive breastfeeding with infections in the upper respiratory ( URTI ) , lower respiratory ( LRTI ) , and gastrointestinal tracts ( GI ) in infancy . METHODS : This study was embedded in the Generation R Study , a population -based prospect i ve cohort study from fetal life onward in the Netherl and s. Rates of breastfeeding during the first 6 months ( never ; partial for < 4 months , not thereafter ; partial for 4–6 months ; exclusive for 4 months , not thereafter ; exclusive for 4 months , partial thereafter ; and exclusive for 6 months ) and doctor-attended infections in the URTI , LRTI , and GI until the age of 12 months were assessed by question naires and available for 4164 subjects . RESULTS : Compared with never-breastfed infants , those who were breastfed exclusively until the age of 4 months and partially thereafter had lower risks of infections in the URTI , LRTI , and GI until the age of 6 months ( adjusted odds ratio [ aOR ] : 0.65 [ 95 % confidence interval ( CI ) : 0.51–0.83 ] ; aOR : 0.50 [ CI : 0.32–0.79 ] ; and aOR : 0.41 [ CI : 0.26–0.64 ] , respectively ) and of LRTI infections between the ages of 7 and 12 months ( aOR : 0.46 [ CI : 0.31–0.69 ] ) . Similar tendencies were observed for infants who were exclusively breastfed for 6 months or longer . Partial breastfeeding , even for 6 months , did not result in significantly lower risks of these infections . CONCLUSIONS : Exclusive breastfeeding until the age of 4 months and partially thereafter was associated with a significant reduction of respiratory and gastrointestinal morbidity in infants . Our findings support health-policy strategies to promote exclusive breastfeeding for at least 4 months , but preferably 6 months , in industrialized countries Abstract Objectives : To investigate the association between the duration of exclusive breast feeding and the development of  asthma related outcomes in children at age 6 years . Design : Prospect i ve cohort study . Setting : Western Australia . Subjects : 2187 children ascertained through antenatal clinics at the major tertiary obstetric hospital in Perth and followed to age 6 years . Main outcome measures : Unconditional logistic regression to model the association between duration of exclusive breast feeding and outcomes related to asthma or atopy at 6 years of age , allowing for several important confounders : sex , gestational age , smoking in the household , and early childcare . Results : After adjustment for confounders , the introduction of milk other than breast milk before 4 months of age was a significant risk factor for all asthma and atopy related outcomes in children aged 6 years : asthma diagnosed by a doctor ( odds ratio 1.25 , 95 % confidence interval 1.02 to 1.52 ) ; wheeze three or more times since 1 year of age ( 1.41 , 1.14 to 1.76 ) ; wheeze in the past year ( 1.31 , 1.05 to 1.64 ) ; sleep disturbance due to wheeze within the past year ( 1.42 , 1.07 to 1.89 ) ; age when doctor diagnosed asthma ( hazard ratio 1.22 , 1.03 to 1.43 ) ; age at first wheeze ( 1.36 , 1.17 to 1.59 ) ; and positive skin prick test reaction to at least one common aeroallergen ( 1.30 , 1.04 to 1.61 ) . Conclusion : A significant reduction in the risk of childhood asthma at age 6 years occurs if exclusive breast feeding is continued for at least the 4 months after birth . These findings are important for our underst and ing of the cause of childhood asthma and suggest that public health interventions to optimise breast feeding may help to reduce the community burden of childhood asthma and its associated traits . Key messages Asthma is the leading cause of admission to hospital in Australian children and its prevalence is increasing Whether breast feeding protects against asthma or atopy , or both , is controversial Asthma is a complex disease , and the relative risks between breast feeding and asthma or atopy are unlikely to be large ; this suggests the need for investigation in a large prospect i ve birth cohort with timely assessment of atopic outcomes and all relevant exposures Exclusive breast feeding for at least 4 months is associated with a significant reduction in the risk of asthma and atopy at age 6 years and with a significant delay in the age at onset of wheezing and asthma being diagnosed by a doctor Public health interventions to promote an increased duration of exclusive breast feeding may help to reduce the morbidity and prevalence of childhood asthma  and BACKGROUND Breast-feeding clearly protects against early wheezing , but recent data suggest that it might increase later risk of atopic disease and asthma . OBJECTIVE We sought to examine the relationship between breast-feeding and later asthma and allergy outcomes by using data from the Avon Longitudinal Study of Parents and Children , a large birth cohort in the United Kingdom . METHODS We used adjusted logistic regression models to evaluate the association between breast-feeding and atopy at age 7 years , bronchial responsiveness to methacholine at age 8 years , and wheeze at ages 3 and 7 1/2 years . Bayesian methods were used to assess the possibility of bias caused by an influence of early wheezing on the duration of breast-feeding , as well as selection bias . RESULTS Breast-feeding was protective for wheeze in the first 3 years of life ( odds ratio [ OR ] of 0.80 [ 95 % CI , 0.70 - 0.90 ] for > or = 6 months relative to never ) but not wheeze ( OR , 0.98 ; 95 % CI , 0.79 - 1.22 ) , atopy ( OR , 1.12 ; 95 % CI , 0.92 - 1.35 ) , or bronchial hyperresponsiveness ( OR , 1.07 ; 95 % CI , 0.82 - 1.40 ) at ages 7 to 8 years . Bayesian models adjusting for the longer duration of breast-feeding among children with wheezing in early infancy produced virtually identical results . CONCLUSIONS We did not find consistent evidence for either a deleterious effect or a protective effect of breast-feeding on later risk of allergic disease in a large prospect i ve birth cohort of children with objective outcome measures and extensive data on potential confounders and effect modifiers . Neither reverse causation nor loss to follow-up appears to have material ly biased our results BACKGROUND Little is known about factors that determine prescribing of  asthma therapy in infancy . OBJECTIVE To describe factors related to the initiation and refill of asthma therapy in infancy . METHODS This study included 1202 infants who participated in a prospect i ve birth cohort study : the ' Wheezing Illnesses Study Leidsche Rijn ( WHISTLER ) ' . Outcomes ,  asthma therapy initiation and refill , were assessed using prescription data . Logistic regression analysis was used to study determinants of therapy initiation in two groups : total population and infants with a respiratory system symptom diagnosis . In addition , determinants of refilling prescriptions were studied in infants who started therapy in their first year of life . RESULTS Fifteen per cent of all infants started asthma therapy in their first year of life . Respiratory symptoms were an important driver of both initiation and refill of prescriptions . In the total population , therapy initiation was associated with male gender [ odds ratio ( OR ) : 1.6 , 95 % confidence interval ( CI ) : 1.1 - 2.6 ] , day-care attendance ( OR : 1.6 , 95 % CI : 1.0 - 2.5 ) and breastfeeding ( OR : 0.6 , 95 % CI : 0.3 - 1.0 ) . For infants with a respiratory system symptom diagnosis , day-care attendance was associated with an increased chance of therapy initiation ( OR : 5.3 , 95 % CI : 1.8 - 16.2 ) and breastfeeding was associated with a lower chance of starting therapy ( OR : 0.4 , 95 % CI : 0.1 - 1.1 ) . Dutch children had a higher chance of refilling prescriptions in infancy ( OR : 5.3 , 95 % CI : 1.1 - 26.8 ) . CONCLUSIONS Apart from other factors involved , the principal reason for initiation and refill of asthma therapy in infancy was the presence of respiratory symptoms . This appeared the only reason to prescribe medication and physicians are not distracted by other factors OBJECTIVE To estimate the prevalence of  wheezing in the chest among adults , and to explore the effect of some variables on the prevalence of this condition . METHODS This was a prospect i ve cohort study on individuals born in the city of Pelotas ( Southern Brazil ) in 1982 . A total of 4,297 subjects was traced in 2004 - 5 , representing 77.4 % of the original cohort . Data were collected by means of interviews using the ISAAC ( International Study of Asthma and Allergies in Childhood Steering Committee ) question naire . Associations between the outcome ' occurrence of wheezing in the chest within the 12 months prior to the interview ' and the variables of socioeconomic , demographic and birth characteristics were tested by means of multivariable analyses , using Poisson regression . RESULTS The prevalence of wheezing over the preceding year was 24.9 % . Among the individuals reporting wheezing , 54.6 % reported difficulty in sleeping , and 12.9 % reported difficulty in speaking due to wheezing . The prevalence of wheezing in the chest was significantly higher among women . This association was maintained in analyses adjusted for non-white skin color , family history of asthma and low socioeconomic level . Among men , there was no significant association in the analyses adjusted for skin color and family income at birth . Family histories of asthma and poverty throughout life presented significant associations with wheezing in the chest . For both sexes , there were no associations with the variables of birth weight and breastfeeding duration . CONCLUSIONS The prevalence of wheezing in the chest was high , and subjects with low family income at birth were more likely to have had wheezing in the chest over the preceding year OBJECTIVES To investigate the relationship of infant feeding to  recurrent wheezing at age 6 years and to assess whether this relationship is altered by a history of wheezing lower respiratory tract illnesses . DESIGN Prospect i ve , longitudinal study of healthy infants followed up from birth to 6 years of age . SETTING Nonselected health maintenance organization population in Tucson , Arizona . PARTICIPANTS There were 1246 healthy infants enrolled at birth , 988 of whom had data on both infant feeding and wheezing at age 6 years . INTERVENTIONS None . MAIN OUTCOME MEASURES Recurrent wheeze ( four or more episodes in the past year ) was assessed by a question naire that was completed by parents when the children were 6 years old . Children were classified by atopic status on the basis of skin prick tests . RESULTS Breast-feeding information was collected prospect ively , and lower respiratory tract illnesses in the first 3 years of life were diagnosed by the pediatrician . Being breast-fed was associated with lower rates of recurrent wheeze at age 6 years ( 3.1 % vs 9.7 % , P < .01 ) for nonatopic children ; this relationship was not significant for atopic children . The relationship of breast-feeding with recurrent wheeze was apparent among nonatopic children both with and without a wheezing lower respiratory tract illness in the first 6 months of life . When potential confounders , including early wheezing lower respiratory tract illness , were included in a multivariate model , nonatopic children who had not been breast-fed had three times the odds of wheezing recurrently ( odds ratio , 3.03 ; confidence interval , 1.06 to 8.69 ) . Eleven percent of recurrent wheeze among nonatopic children could be attributed to not breast-feeding . CONCLUSIONS Recurrent wheeze at age 6 years is less common among nonatopic children who were breast-fed as infants . This effect is independent of whether the child wheezed with a lower respiratory tract illness in the first 6 months of life The relationship between  breastfeeding , respiratory and other allergic disorders has been controversial . Our aim was to investigate the relationships between  breastfeeding  , respiratory outcomes , eczema and atopy at 15 months of age in a prospect i ve birth cohort in New Zeal and . A total of 1105 children were enrolled at birth , and 1011 ( 91.2 % ) were followed up at 15 months .  Logistic regression was used to model associations between  breastfeeding  duration and respiratory outcomes , eczema and atopy after adjusting for relevant confounding variables : ethnicity , socio-economic status , parity , body mass index , smoking in pregnancy , gender and respiratory infections in the first 3 months of life . Breastfeeding was associated with a significant reduction in the risk of adverse respiratory outcomes at 15 months . After adjustment for confounders , each month of exclusive breastfeeding reduced the risk of doctor-diagnosed asthma by 20 % ( odds ratio 0.80 , 95 % confidence interval 0.71 to 0.90 ) , wheezing by 12 % ( 0.88 , 0.82 to 0.94 ) and inhaler use by 14 % ( 0.86 , 0.78 to 0.93 ) . Associations for both exclusive and additional  breastfeeding duration s , and respiratory outcomes remained independently significant when modelled simultaneously . Although independently associated with all respiratory outcomes , adjusting for parental history of allergic disease or maternal history of asthma did not alter our findings . Breastfeeding was not associated with eczema or atopy at 15 months . In conclusion , there was a significant protective effect of breastfeeding on infant wheezing and other adverse respiratory outcomes that may be early indicators of asthma in New Zeal and children Risk factors for  wheezing during the first year of life  ( a major cause of respiratory morbidity worldwide ) are poorly known in non-affluent countries . We studied and compared risk factors in infants living in affluent and non-affluent areas of the world . A population -based study was carried out in r and om sample s of infants from centres in Latin America ( LA ) and Europe ( EU ) . Parents answered vali date d question naires referring to the first year of their infant 's life during routine health visits . Wheezing was stratified into occasional ( 1 - 2 episodes , OW ) and recurrent ( 3 + episodes , RW ) . Among the 28687 infants included , the most important independent risk factors for OW and RW ( both in LA and in EU ) were having a cold during the first 3 months of life [ OR for RW 3.12 ( 2.60 - 3.78 ) and 3.15 ( 2.51 - 3.97 ) ; population attributable fraction ( PAF ) 25.0 % and 23.7 % ] ; and attending nursery school [ OR for RW 2.50 ( 2.04 - 3.08 ) and 3.09 ( 2.04 - 4.67 ) ; PAF 7.4 % and 20.3 % ] . Other risk factors were as follows : male gender , smoking during pregnancy , family history of asthma/rhinitis , and infant eczema . Breast feeding for > 3 months protected from RW [ OR 0.8 ( 0.71 - 0.89 ) in LA and 0.77 ( 0.63 - 0.93 ) in EU ] . University studies of mother protected only in LA [ OR for OW 0.85 ( 0.76 - 0.95 ) and for RW 0.80 ( 0.70 - 0.90 ) ] . Although most risk factors for wheezing are common in LA and EU ; their public health impact may be quite different . Avoiding nursery schools and smoking in pregnancy , breastfeeding babies > 3 months , and improving mother 's education would have a substantial impact in lowering its prevalence worldwide Asthma is a leading cause of morbidity for children and is a major public health problem in Australia . Ecological and temporal data suggest that dietary factors may have a role in recent increases in the prevalence of asthma . Aim : The aim of conducting this study was to investigate whether  childhood asthma was associated with the ratio of omega 6 ( n‐6 ) to omega 3 ( n‐3 ) fatty acids in the diet ( n‐6:n‐3 ) . Method : The Western Australian Pregnancy Cohort Study is a prospect i ve birth cohort of 2602 children . Using a nested case‐control cross‐sectional study design within this cohort , a group of children were identified as cases with current asthma at 6 or at 8 years of age or as controls with no asthma at 6 or at 8 years .  Dietary details including n‐6 and n‐3 fatty acid intake data were collected by parent response to a question naire when the children were 8 years old . Logistical regression was used to compare quartiles of n‐6:n‐3 intake in cases and controls . Adjustment was made for covariates : gender , gestational age , breastfeeding , older siblings , maternal smoking during pregnancy , maternal age , maternal asthma , child 's current age in months , body mass index , total energy intake , and antioxidant intake  ( vitamins A , C , E , and zinc ) . Results : A response rate of 83 % was achieved by providing complete data from 335 children [ 49 % cases with current asthma ( n = 166 ) , 51 % controls ( n = 169 ) ] . Following adjustment for covariates the association between the ratio of n‐6:n‐3 fatty acids and risk for current asthma was statistically significant ( p = 0.022 ) . Conclusion : We found evidence for a modulatory effect of the dietary n‐6:n‐3 fatty acid ratio on the presence of asthma in children . Our results provide evidence that promotion of a diet with increased n‐3 fatty acids and reduced n‐6 fatty acids to protect children against symptoms of asthma is warranted The association between  breastfeeding and wheezing , lung function and atopy  was evaluated in the International Study of Asthma and Allergy in Childhood ( ISAAC ) Phase II . Cross-sectional studies were performed in 27 centres in 20 countries . Information on disease and exposure factors was collected by parental question naires . Data from 54,000 r and omly selected school children ( aged 8–12 yrs , 31,759 with skin prick testing ) and a stratified sub sample ( n = 4,888 ) were used for testing the correlation of breastfeeding with bronchial hyperreactivity and lung function . R and om effect models for meta- analysis were applied to calculate combined odds ratios ( ORs ) . Any breastfeeding was associated with less wheeze both in affluent ( adjusted OR ( ORadj ) 0.87 , 95 % confidence interval ( CI ) 0.78–0.97 ) and nonaffluent countries ( ORadj 0.80 , 95 % CI 0.68–0.94 ) . Further analyses revealed that this was true only for nonatopic wheeze in nonaffluent countries ( ORadj 0.69 , 95 % CI 0.53–0.90 ) . Breastfeeding was not associated with atopic wheeze and objective measures of allergy in both affluent and nonaffluent countries . In contrast , breastfeeding was associated with higher predicted forced expiratory volume in one second in affluent countries only ( mean ratio 1.11 , 95 % CI 1.02–1.20 ) . Breastfeeding is associated with protection against nonatopic wheeze , which becomes particularly evident in nonaffluent countries . Overall , breastfeeding was not related to any measure of allergy . These findings may explain some of the controversy regarding breastfeeding , since the direction of the association with breastfeeding depends on the predominating wheeze phenotype ( e.g. atopic , nonatopic ) OBJECTIVE To evaluate the impact of exclusive breastfeeding and introduction of cow 's milk in the first year of life on the diagnosis of  asthma , wheezing , and atopy in children aged 3 to 4 years . METHODS This is a cohort study nested in a r and omized field trial investigating the effectiveness of dietary guidelines during the first year of life of children in the city of São Leopoldo , southern Brazil . Children who had their diet monitored during the first year of life , in a primary study , were revisited three years later , when their parents answered a question naire related to respiratory problems , applied during home visits by trained interviewers . Children were also skin-prick tested to assess responses to common environmental allergens . RESULTS Of the 397 children followed during the first year of life , 354 were reassessed between 3 and 4 years of age . Prevalence of wheezing , evaluated for the 12 months prior to question naires , was 21.3 % , while prevalence of asthma and atopy was 5.5 and 28.7 % , respectively . Children  fed cow 's milk previous to being four months of life were significantly more likely to have asthma between three and four years of age ( OR 3.22 ; 95%CI 1.05 - 9.80 ) . In the same line , exclusive breastfeeding for a period shorter than six months was marginally associated with atopy . CONCLUSIONS The early introduction of cow 's milk was an important risk factor for triggering asthma/wheeze symptoms at the age of 4 years . Exclusive breastfeeding for longer than six months was also potentially associated with protection against the development of atopy . The results of this study suggest that dietary interventions during the first year of life have the potential to reduce the impact of asthma , and possibly , atopy BACKGROUND Atopic dermatitis ( AD ) often develops in infancy as the first manifestation of the atopic phenotype . Wheezing is also common in infancy , but it is less clear whether infant wheezing should be considered as an atopic phenotype . If infant wheeze and AD share a common aetiology , this would indicate that infant wheezing is an atopic phenotype . OBJECTIVE To investigate whether potential risk factors for infant wheeze and AD have similar effects on these 2 phenotypes , indicating a common etiology . METHODS A total of 34.793 mother-child pairs enrolled in the Danish National Birth Cohort were followed prospect ively . Information on wheezing episodes , AD , and prenatal , perinatal , and postnatal risk factors was collected by interview at 12 and 30 weeks of gestation , at 6 and 18 months of age , and by linkage to the Danish Medical Birth Register . Data were analyzed by binary and polytomous logistic regression models . RESULTS The following variables had significantly differential effects on infant wheezing and AD : parental hay fever , parental asthma , parental AD , sex , maternal age , maternal occupation , smoking during pregnancy , season of birth , birth weight , gestational age , head circumference , breast-feeding , number of older siblings , day care attendance , and pets in the home . CONCLUSION The majority of risk factors had differential effects on infant wheeze and AD indicative of a different etiology . Infant wheezing does not seem to be etiologically linked to the epidemic of atopic disease , and infant wheezing should not be used as an indicator of the atopic phenotype The objectives of the present study were to quantify the association of atopy and respiratory infections with asthma , and exclusive breastfeeding with  respiratory illness , atopy and asthma in children . A cohort study of 2,602 children enrolled prior to birth and followed prospect ively , provided data on respiratory illness , the method of feeding in the first year of life , as reported on a prospect i ve diary card , and current asthma at the age of 6 yrs ( defined as doctor-diagnosed asthma with wheeze in the last year or cough without a cold , and currently taking either preventer or reliever asthma medication ) , as reported by parental question naire .  Atopy  was defined by a positive skin-prick test assessed at the age of 6 yrs . Wheezing lower respiratory illness ( LRI ) in the first year of life , particularly multiple episodes of wheezing LRI , increased the risk for current asthma in both nonatopic ( odds ratio ( OR ) 4.10 , p⪕0.0005 ) and atopic children ( OR 9.00 , p⪕0.0005 ) , but did not increase the risk for atopy . In contrast , up to three upper respiratory tract infections demonstrated a negative association and four or more a positive risk for current asthma in unadjusted ( p=0.006 ) and adjusted ( p=0.057 ) analysis . Following adjustment , exclusive breastfeeding for < 4 months was associated with an increased risk for current asthma ( OR 1.36 , 95 % confidence interval 1.00–1.85 , p=0.047 ) . Wheezing lower respiratory illness in the first year of life and atopy are independently associated with increased risk for current asthma at the age of 6 yrs , suggesting that their effects are mediated via different causal pathways and that these risk factors are multiplicative when they operate concomitantly within individual children . Exclusive breastfeeding protects against asthma via effects on both these pathways , as well as through other as yet undefined mechanisms The fact that breastfeeding may protect against allergic disease remains controversial , with hardly any reports from developing countries . This study investigated the association between allergic disease in children and prolonged breastfeeding .  Data were collected from a 15 % r and om sample of households from two poor suburbs of Cape Town , South Africa . Parents completed a vali date d International Study on Asthma and Allergies in Childhood question naire on allergic diseases for children aged 6–14 yrs . Other questions included breastfeeding duration , maternal smoking and parental allergy . Results were adjusted for possible confounders and for possible clustering within the household . Out of the 861 children included in the study , allergic disease in general , and hay fever in particular , were significantly less frequent in those with prolonged ( ≥6 months ) breastfeeding . There was a significant linear inverse association between breastfeeding duration and allergic disease in children without allergic parents , but not in children with an allergic predisposition . In conclusion , these results from a developing country suggest a protective effect of prolonged breastfeeding on the development of allergic disease , particularly hay fever , in children born to nonallergic parents . This protective effect was not found in children with an allergic predisposition The relationship of milk diet and solid feeding practice s during the first 4 months of life to rates of early childhood asthma  was studied prospect ively in a birth cohort of 1110 children . The results of the analysis showed no significant association between rates of asthma and breast feeding or solid feeding practice s. This was true for children both of asthmatic and non-asthmatic parentage . It is concluded that there is no evidence to indicate that early breast feeding had any detectable effect on the risk of subsequent asthma in this birth cohort . However , the possibility still remains that breast feeding may have a prophylactic effect for children from highly atopic families Background Studies on the health benefits from breastfeeding often rely on maternal recall of breastfeeding . Although short-term maternal recall has been found to be quite accurate , less is known about long-term accuracy . The objective of this study was to assess the accuracy of long-term maternal  recall of breastfeeding duration . Methods In a prospect i ve study of pregnancy and birth outcome , detailed information on breastfeeding during the child ’s first year of life was collected from a cohort of Norwegian women who gave birth in 1986–88 . Among 374 of the participants , data on  breastfeeding  initiation and duration  were compared to recalled data obtained from mailed question naires some 20 years later .  Intraclass correlation coefficient ( ICC ) , Bl and -Altman plot , and Kappa statistics were used to assess the agreement between the two sources of data .  Logistic  regression was used to assess predictors of misreporting breastfeeding duration by more than one month . Results Recorded and recalled breastfeeding duration were strongly correlated ( ICC=0.82 , p < 0.001 ) . Nearly two thirds of women recalled their breastfeeding to within one month . Recall data showed a modest median overestimation of about 2 weeks . There were no apparent systematic discrepancies between the two sources of information , but recall error was predicted by the age when infants were introduced to another kind of milk . Across categories of breastfeeding , the overall weighted Kappa statistic showed an almost perfect agreement ( κ = 0.85 , 95 % confidence interval [ CI ] 0.82 – 0.88 ) . Conclusion  Breastfeeding duration  was recalled quite accurately 20 years after mothers gave birth in a population where breastfeeding is common and its duration long Background : For many years it has been assumed that the risk of childhood respiratory allergies is related to allergen exposures in early life . There are , however , few prospect i ve data in support . We aim ed to examine this relationship in a representative cohort of children born in Ashford , Kent ( UK ) . Methods : 625 children ( 94 % of those eligible ) were followed from birth to the age of 5.5 years at which time 552 underwent skin prick testing to extracts of house dust mite and cat fur allergens . Maternal reports of wheeze in the last year were collected by interview . These outcomes were related to individual domestic concentrations of Der p 1 and Fel d I allergens estimated from dust collection at the age of 8 weeks . Results : 10 % of children were sensitised to house dust mite or cat at age 5.5 years ; 7 % had atopic wheeze . No significant relationships between allergen exposure and either sensitisation or wheeze were found but , on examination , the exposure-response relationships for both allergens and for each outcome rose steeply at low levels of exposure and were attenuated at high levels of exposure . These patterns were modified by paternal atopy and by birth order . Conclusions : There are no linear relationships between early allergen exposure and the induction of childhood respiratory allergy ; rather , the risks of IgE sensitisation and asthma rise at very low levels of exposure and are attenuated thereafter . These patterns are influenced by parental atopy and birth order . These findings suggest important gene-environment interactions in the development of atopy and asthma and imply that reductions in domestic allergen exposure alone are unlikely to have a major impact in decreasing the incidence of these diseases in childhood BACKGROUND The relationship between infant feeding and childhood asthma is controversial . This study tested the hypothesis that the relation between breast feeding and childhood asthma is altered by the presence of maternal asthma . METHODS Healthy non-selected newborn infants ( n=1246 ) were enrolled at birth . Asthma was defined as a physician diagnosis of asthma plus asthma symptoms reported on ⩾2 question naires at 6 , 9 , 11 or 13 years . Recurrent wheeze ( ⩾4 episodes in the past year ) was reported by question naire at seven ages in the first 13 years of life . Duration of exclusive breast feeding was based on prospect i ve physician reports or parental question naires completed at 18 months . Atopy was assessed by skin test responses at the age of 6 years . RESULTS The relationship between  breast feeding , asthma , and wheeze differed with the presence or absence of maternal asthma and atopy in the child . After adjusting for confounders , children with asthmatic mothers were significantly more likely to have asthma if they had been exclusively breast fed ( OR 8.7 , 95 % CI 3.4 to 22.2 ) . This relationship was only evident for atopic children and persisted after adjusting for confounders . In contrast , the relation between recurrent wheeze and breast feeding was age dependent . In the first 2 years of life exclusive breast feeding was associated with significantly lower rates of recurrent wheeze ( OR 0.45 , 95 % CI 0.2 to 0.9 ) , regardless of the presence or absence of maternal asthma or atopy in the child . Beginning at the age of 6 years , exclusive breast feeding was unrelated to prevalence of recurrent wheeze , except for children with asthmatic mothers in whom it was associated with a higher odds ratio for wheeze ( OR 5.7 , 95 % CI 2.3 to 14.1 ) , especially if the child was atopic . CONCLUSION The relationship between breast feeding and asthma or recurrent wheeze varies with the age of the child and the presence or absence of maternal asthma and atopy in the child . While associated with protection against recurrent wheeze early in life , breast feeding is associated with an increased risk of asthma and recurrent wheeze beginning at the age of 6 years , but only for atopic children with asthmatic mothers The effect of withholding cows ' milk was examined in 487 infants at high risk of allergic disease . Before birth they were r and omly allocated either to a control group , most of whom received cows ' milk preparations , or to an intervention group , who were offered a soya based substitute .  Eczema and wheezing occurred to a similar extent in the two groups during the first year of life , although napkin rash , diarrhoea , and oral thrush were commoner in the intervention group , especially during the first three months . Breast feeding for any length of time was associated with a reduced incidence of wheezing and diarrhoea BACKGROUND In Phase Three of the International Study of Asthma and Allergies in Childhood ( ISAAC ) , we investigated the relationship between breast feeding in infancy and symptoms of asthma , rhinoconjunctivitis and eczema in 6 - 7 year old children . METHODS Parents or guardians of 6 - 7 year old children completed written question naires on current symptoms of asthma , rhinoconjunctivitis and eczema , and on a range of possible asthma risk factors including a history of  breast feeding ever . Prevalence odds ratios were estimated using logistic regression , adjusted for gender , region of the world , language , per capita gross national income , and other risk factors . RESULTS In all 206,453 children from 72 centres in 31 countries participated in the study . Reported breast feeding ever was not associated with current wheeze , with an odds ratio ( adjusted for gender , region of the world , language , per capita gross national income , and factors encountered in infancy ) of 0.99 ( 95 % CI 0.92 - 1.05 ) , current rhinoconjunctivitis ( OR 1.00 , 95 % CI 0.93 - 1.08 ) , current eczema ( OR 1.05 , 95 % CI 0.97 - 1.12 ) , or symptoms of severe asthma ( OR 0.95 , 95 % CI 0.87 - 1.05 ) . Breast feeding was however associated with a reduced risk of severe rhinoconjunctivitis ( OR 0.74 , 95 % CI 0.59 - 0.94 ) and severe eczema ( OR 0.79 , 95 % CI 0.66 - 0.95 ) . CONCLUSIONS There was no consistent association between breast feeding use in the first year of life and either a history or current symptoms of wheezing , rhinoconjunctivitis or eczema in 6 - 7 year old children , but possibly an effect on severe symptoms of the latter two conditions Background and aims : There are few st and ardised question naires for the assessment of respiratory symptoms  in preschool children . We have developed and tested the short-term repeatability of a postal question naire on respiratory symptoms for 1-year-old children . Methods : A newly developed postal question naire for the assessment of wheeze and other respiratory symptoms was sent to parents of a population -based r and om sample of 4300 children aged 12–24 months . After an interval of 3 months , a r and om sample of 800 respondents received the question naire a second time . The responses were compared using Cohen ’s kappa ( & kgr ; ) to assess agreement corrected for chance . Results : The first question naire was returned by 3194 ( 74 % ) families , the second one by 460/800 ( 58 % ) . Repeatability was excellent ( & kgr ; 0.80–0.96 ) for questions on household characteristics , environmental exposures and family history , good ( & kgr ; 0.61–0.80 ) for questions on prevalence , severity and treatment of wheeze , and moderate ( & kgr ; 0.39–0.66 ) for chronic cough and upper respiratory symptoms . Conclusions : This short postal question naire design ed for use in population -based studies has excellent repeatability for family and household characteristics and good repeatability for questions on wheeze . Short-term changes in symptom status might be responsible for variable answers on recent chronic cough and upper respiratory symptoms . Overall , the question naire is a valuable instrument for community-based research on respiratory symptoms in 1 to 2-year-old children Clinical course and environmental factors were recorded in a prospect i ve study of 276 unselected infants followed from birth to the age of 18 months . The study was performed with a question naire at the age of 6 and 12 months and a physical examination at 18 months . Fifty‐nine ( 21 % ) of the children had ≥2 episodes of wheezing before they were 18 months old . A total of 58 ( 21 % ) of the children belonged to the lowest social class V , 182 ( 66 % ) were daily exposed to passive tobacco smoking at home and /or in daycare , 164 ( 59 % ) were breastfed ≥3 months , 192 ( 70 % ) were in daycare , 62 ( 22 % ) lived in Hats and 167 ( 61 % ) were in daily contact with furred pets at home and /or in daycare . In social class V a preponderance of children were exposed to passive tobacco smoking , a majority were living in flats and a minority were breastfed ≥ 3 months . Linear logistic regression analysis was used for the purpose of assessing the causal effect of environmental risk factors on the risk of recurrent episodes of wheezing before the age of 18 months . The study demonstrated that male sex and daily exposure to passive tobacco smoking were significant risk factors with estimated odds ratios 1.9 and 2.4 , respectively . Maternal tobacco smoking seemed to be associated with the higest risk . There was a tendency – though not significant – indicating that breastfeeding ≥ 3 months had a protective effect . Low social status , daycare , daily contact with furred pets , having carpeted floor in bedroom , and living in a flat proved not to affect significantly the risk of recurrent wheezing Epidemiological evidence for an effect of breastfeeding on asthma continues to be inconclusive . The present prospect i ve study examined the relationship between breastfeeding and the  risk of wheeze and asthma in Japanese infants . A birth cohort of 763 infants was followed . The first survey during pregnancy and the second survey between 2 and 9 months postpartum collected information on potential confounding factors . Data on  breastfeeding , wheeze , and asthma were obtained from question naires in the third survey from 16 to 24 months postpartum . Adjustment was made for maternal age , maternal and paternal history of asthma , atopic eczema , and allergic rhinitis , indoor domestic pets ( cats , dogs , birds , or hamsters ) , family income , maternal and paternal education , maternal smoking during pregnancy , baby 's sex , baby 's older siblings , household smoking in the same room as the infant , and time of delivery before the third survey . By the third survey , the cumulative incidence of wheeze and asthma was 22.1 % and 4.3 % , respectively . Neither exclusive breastfeeding for 4 months or more nor partial breastfeeding for 6 months or more were material ly related to the risk of wheeze . No measurable association was observed between exclusive breastfeeding for 4 months or more and the risk of asthma .  Partial breastfeeding for 6 months or more was inversely related to the risk of asthma although the adjusted odds ratio ( OR ) was not statistically significant . When infants were stratified according to whether there was a negative or positive allergic history in at least 1 parent , a nearly 40 % and 60 % decrease , respectively , in the ORs were found for exclusive and partial breastfeeding only in infants without a parental allergic history , although the ORs were not statistically significant . The present prospect i ve study showed no statistically significant relationship between  breastfeeding duration and the risk of wheeze or asthma in Japanese infants BACKGROUND There are conflicting data on the effect of day-care attendance and position in sibship on the development of wheezing . OBJECTIVE To investigate the relationship between day-care attendance and position in sibship with early childhood wheeze .  METHODS Prospect i ve population -based birth cohort . At age 5 years , we collected information on parentally  reported symptoms ( n = 922 ) ; lung function was ascertained using plethysmography ( n = 745 ) and allergic sensitization by skin testing ( n = 815 ) . Participants were assigned into categories according to the age of entry to day-care ( 0 - 6 , 6 - 12 , > 12 mo ) and number of older siblings ( 0 , 1 , 2 , > 2 ) . RESULTS Current wheeze  was reported by 203 participants ( 22 % ) ; 224 ( 28 % ) were sensitized . In the multivariate model , sensitization ( odds ratio , 2.47 ; 95 % CI , 1.66 - 3.67 ) , male sex ( 1.49 , 1.01 - 2.20 ) , maternal asthma ( 1.72 , 1.10 - 2.68 ) , and maternal smoking during pregnancy ( 2.15 , 1.26 - 3.66 ) significantly increased the risk of wheezing . Entering day-care between 6 and 12 or after 12 months of age was significantly and inversely associated with current wheeze ( 0.25 , 0.11 - 0.60 ; and 0.65 , 0.44 - 0.98 , respectively ) . Entry into nursery between 6 and 12 months reduced the risk of persistent wheezing ( P = .04 ) . We found no association between day-care attendance and lung function . Entering nursery in the first 6 months of life was associated with increased risk of atopy ( 2.47 , 1.23 - 4.95 ) . Having older siblings was associated only with rhinoconjunctivitis ( 0.72 , 0.54 - 0.97 ) . CONCLUSION Day-care attendance was associated with a reduced risk of  current wheezing in 5-year-old children . The protective effect appeared strongest for children who entered day-care between the ages of 6 and 12 months OBJECTIVES : To compare the relation between relative deprivation , its associated social risk factors and the prevalence of wheeze in infancy and in adulthood . DESIGN : A cross sectional population study . SETTING : The three District Health Authorities of Bristol . SUBJECTS : A r and om sample of 1954 women stratified by age and housing tenure to be representative of women with children < 1 in Great Britain and selected from the Avon Longitudinal Study of Pregnancy and Childhood ( ALSPAC ) . MAIN OUTCOME MEASURES : The prevalence of wheeze for infants at six months after birth and for their mothers and fathers at eight months postpartum . Potential mediators of the relation between  relative deprivation  and wheeze measured were overcrowded living conditions , number of other siblings in the household , damp or mouldy housing conditions , maternal and paternal smoking behaviour , and infant feeding practice . RESULTS : 63.4 % ( 1239 ) of the sample lived in owner occupied/mortgaged accommodation ( relatively affluent ) and 36.6 % ( 715 ) lived in council house/rented accommodation ( relatively deprived ) . Wheeze was significantly more likely for infants living in council house/rented accommodation ( chi 2 = 15.93 , df = 1 , p < 0.0001 ) , their mothers ( chi 2 = 9.28 , df = 1 , p < 0.001 ) and their fathers ( chi 2 = 7.41 , df = 1 , p < 0.01 ) . For those living in council house/rented accommodation backward stepwise logistic regression analyses showed that infants with other siblings in the household were significantly more likely to wheeze ( OR = 1.83 , 95 % CI = 1.27 , 2.65 ) , as were infants whose mothers smoked ( OR = 1.82 , 95 % CI = 1.30 , 2.55 ) and those who were breast fed for less than three months ( OR = 0.66 , 95 % CI = 0.44 , 0.98 ) . Mothers with a partner who smoked were significantly more likely to report wheeze ( OR = 1.73 , 95 % CI = 1.05 , 2.85 ) . There was no independent association between the social factors included in the analysis and the likelihood of wheeze for fathers . CONCLUSIONS : This study identified differences in the social factors associated with a higher prevalence of wheeze in infancy and in adulthood ; results suggested that this symptom was commonly linked to infection in infancy , but not in adulthood . While environmental tobacco smoke was associated with a higher prevalence of wheeze in infancy and in adulthood , this does not necessarily indicate a common underlying mechanism ; possible explanations are discussed BACKGROUND The literature regarding the association between breast-feeding and atopic diseases has been contradictory . OBJECTIVE We have assessed the relationship between breast-feeding and atopic disorders in a cohort followed into middle age . METHODS The Tasmanian Asthma Study is a population -based prospect i ve cohort study that has followed participants from the age of 7 to 44 years .  Exclusive breast-feeding in the first 3 months of life was examined as a risk factor for atopic diseases by using multiple logistic regression and generalized estimating equation analyses . RESULTS At age 7 years , exclusively breast-fed children with a maternal history of atopy had a marginally lesser risk of current asthma than those not exclusively breast-fed ( odds ratio [ OR ] , 0.8 ; 95 % CI , 0.6 - 1.0 ) . However , after age 7 years , the risk reversed , and exclusively breast-fed children had an increased risk of current asthma at 14 ( OR , 1.46 ; 95 % CI , 1.02 - 2.07 ) , 32 ( OR , 1.84 ; 95 % CI , 1.06 - 3.3 ) , and 44 ( OR , 1.57 ; 95 % CI , 1.15 - 2.14 ) years . Exclusively breast-fed children also had a reduced risk of food allergy at age 7 years but an increased risk of food allergy ( OR , 1.26 ; 95 % CI , 1.1 - 1.5 ) and allergic rhinitis ( OR , 1.2 ; 95 % CI , 1.0 - 1.3 ) at 44 years . CONCLUSION Exclusively breast-fed babies with a maternal history of atopy were less likely to develop asthma before the age of 7 years , but more likely to develop asthma after the age of 7 years . CLINICAL IMPLICATION S The current recommendation to breast-feed high-risk infants for protection against early wheezing illness can be confirmed . However , the recommendation should be reconsidered for protection against allergic asthma and atopy in the longer term CONTEXT Current evidence that breastfeeding is beneficial for infant and child health is based exclusively on observational studies . Potential sources of bias in such studies have led to doubts about the magnitude of these health benefits in industrialized countries . OBJECTIVE To assess the effects of breastfeeding promotion on breastfeeding duration and exclusivity and gastrointestinal and respiratory infection and atopic eczema among infants . DESIGN The Promotion of Breastfeeding Intervention Trial ( PROBIT ) , a cluster-r and omized trial conducted June 1996-December 1997 with a 1-year follow-up . SETTING Thirty-one maternity hospitals and polyclinics in the Republic of Belarus . PARTICIPANTS A total of 17 046 mother-infant pairs consisting of full-term singleton infants weighing at least 2500 g and their healthy mothers who intended to breastfeed , 16491 ( 96.7 % ) of which completed the entire 12 months of follow-up . INTERVENTIONS Sites were r and omly assigned to receive an experimental intervention ( n = 16 ) modeled on the Baby-Friendly Hospital Initiative of the World Health Organization and United Nations Children 's Fund , which emphasizes health care worker assistance with initiating and maintaining breastfeeding and lactation and postnatal breastfeeding support , or a control intervention ( n = 15 ) of continuing usual infant feeding practice s and policies . MAIN OUTCOME MEASURES Duration of any breastfeeding , prevalence of predominant and exclusive breastfeeding at 3 and 6 months of life and occurrence of 1 or more episodes of gastrointestinal tract infection , 2 or more episodes of respiratory tract infection , and atopic eczema during the first 12 months of life , compared between the intervention and control groups . RESULTS Infants from the intervention sites were significantly more likely than control infants to be breastfed to any degree at 12 months ( 19.7 % vs 11.4 % ; adjusted odds ratio [ OR ] , 0.47 ; 95 % confidence interval [ CI ] , 0.32 - 0.69 ) , were more likely to be exclusively breastfed at 3 months ( 43.3 % vs 6.4 % ; P<.001 ) and at 6 months ( 7.9 % vs 0.6 % ; P = .01 ) , and had a significant reduction in the risk of 1 or more gastrointestinal tract infections ( 9.1 % vs 13.2 % ; adjusted OR , 0.60 ; 95 % CI , 0.40 - 0.91 ) and of atopic eczema ( 3.3 % vs 6.3 % ; adjusted OR , 0.54 ; 95 % CI , 0.31 - 0.95 ) , but no significant reduction in respiratory tract infection ( intervention group , 39.2 % ; control group , 39.4 % ; adjusted OR , 0.87 ; 95 % CI , 0.59 - 1.28 ) . CONCLUSIONS Our experimental intervention increased the duration and degree ( exclusivity ) of breastfeeding and decreased the risk of gastrointestinal tract infection and atopic eczema in the first year of life . These results provide a solid scientific underpinning for future interventions to promote breastfeeding RATIONALE The protective effect of breastfeeding on early respiratory infections is well established , but its relationship to the development of subsequent asthma remains controversial . OBJECTIVES To clarify these complex issues , we examined the association between lung function and infant-feeding practice s. METHODS In the Tucson Children 's Respiratory Study , feeding practice s were assessed prospect ively based on question naires completed at enrollment and well-child visits . Formula introduction was categorized as having occurred before 2 months ( n = 143 , " early formula introduction ") , from 2 and before 4 months ( n = 336 ) , or at 4 months and older ( n = 200 , " longer breastfed " ) . Lung function was measured at age 11 and 16 years . A r and om-effects model was used to assess the relationship of infant-feeding practice s to measures of lung function . MEASUREMENTS AND MAIN RESULTS FVC by age 16 was increased by 103 + /- 40.0 ml ( P = 0.01 ) , and the FEV1/FVC ratio was lower ( -1.9 + /- 0.6 % , P = 0.004 ) in the longer breastfed children compared with children with early formula introduction . This effect was modified after stratifying by maternal asthma . Compared with children with early formula introduction , longer breastfed children with asthmatic mothers had an FVC that was not increased ( P = 0.7 ) and an FEV1/FVC ratio ( -5.7 + /- 2.4 % , P = 0.02 ) that was significantly decreased by age 16 . Longer breastfed children with nonatopic , nonasthmatic mothers demonstrated an increased FVC ( 142 + /- 71.1 ml , P = 0.047 ) and no decrease in FEV1/FVC ( P = 0.7 ) compared with children with early formula introduction . CONCLUSIONS Longer duration of breastfeeding favorably influences lung growth  in children . However , in the presence of maternal asthma , longer breastfeeding is associated with decreased airflows BACKGROUND AND OBJECTIVE This study examined prenatal , perinatal and early childhood predictors of wheezing phenotypes in the first decade of life . METHODS Information on current wheezing , was collected prospect ively from five surveys conducted every 2 years over the first decade of life . Five wheezing phenotypes were defined : non-wheezers , preschool , primary -school , intermittent and persistent wheezers .  Logistic regression with adjustment for survey design was used to determine the predictors of wheezing phenotypes . RESULTS Data on 2711 children were used in the analysis . Early respiratory infection , the child 's allergy and parental asthma were significant risk factors for preschool , intermittent and persistent wheeze . The child 's allergy and parental asthma had stronger associations with persistent wheeze than with preschool wheeze . Breastfeeding was a significant predictor of both preschool and intermittent wheezing . Daycare attendance  was a risk factor for preschool wheeze but a protective factor for primary -school wheezing . Crowding at home was a protective factor for both preschool and primary -school wheeze . Parental smoking was a significant factor for preschool wheeze . CONCLUSION This study identified different predictors for each wheezing phenotype with some degree of overlap . The observed differential effects for these conditions raises the possibility that there are different aetiologies for asthma among children Aims : To investigate the effect of breast feeding on  allergic disease in infants up to 2 years of age . Methods : A birth cohort of 4089 infants was followed prospect ively in Stockholm , Sweden . Information about various exposures was obtained by parental question naires when the infants were 2 months old , and about allergic symptoms and feeding at 1 and 2 years of age . Duration of exclusive and partial breast feeding was assessed separately . Symptom related definitions of various allergic diseases were used . Odds ratios ( OR ) and 95 % confidence intervals ( CI ) were estimated in a multiple logistic regression model . Adjustments were made for potential confounders . Results : Children exclusively breast fed during four months or more exhibited less asthma ( 7.7 % v 12 % , ORadj = 0.7 , 95 % CI 0.5 to 0.8 ) , less atopic dermatitis ( 24 % v 27 % , ORadj = 0.8 , 95 % CI 0.7 to 1.0 ) , and less suspected allergic rhinitis ( 6.5 % v 9 % , ORadj = 0.7 , 95 % CI 0.5 to 1.0 ) by 2 years of age . There was a significant risk reduction for asthma related to partial breast feeding during six months or more ( ORadj = 0.7 , 95 % CI 0.5 to 0.9 ) . Three or more of five possible allergic disorders — asthma , suspected allergic rhinitis , atopic dermatitis , food allergy related symptoms , and suspected allergic respiratory symptoms after exposure to pets or pollen — were found in 6.5 % of the children . Exclusive breast feeding prevented children from having multiple allergic disease ( ORadj = 0.7 , 95 % CI 0.5 to 0.9 ) during the first two years of life . Conclusion : Exclusive breast feeding seems to have a preventive effect on the early development of allergic disease — that is , asthma , atopic dermatitis , and suspected allergic rhinitis , up to 2 years of age . This protective effect was also evident for multiple allergic disease OBJECTIVE . The use of antibiotics in infancy and subsequent changes in the intestinal bacterial flora have been discussed as risk factors for the development of  asthma .  However , it has been difficult to exclude the possibility that antibiotics have been given in early episodes of wheezing . As a result , there has been a risk of reverse causation . To minimize the risk of reverse causation , we have focused on the effect of antibiotics that are already administered on the neonatal ward . METHODS . In a cohort study of infants born in western Sweden in 2003 , we studied the development of wheezing . The families of the infants were r and omly selected and sent a question naire at child ages 6 and 12 months . The response rate was 68.5 % to the 6-month question naire and 68.9 % to the 12-month question naire . RESULTS . At 12 months , 20.2 % of infants had had 1 or more episodes of wheezing , and 5.3 % had had 3 or more episodes . Inhaled corticosteroids had been taken by 4.1 % of the infants . Independent risk factors for wheezing disorder treated with inhaled corticosteroids were neonatal antibiotic treatment , male gender , gestational age of < 37 weeks , having a mother with asthma , having a sibling with asthma or eczema , and breastfeeding for < 5 months . CONCLUSIONS . Treatment with antibiotics in the neonatal period was an independent risk factor for wheezing that was treated with inhaled corticosteroids at 12 months of age . These results indirectly support the hypothesis that an alteration in the intestinal flora can increase the risk of subsequent wheezing BACKGROUND Some r and omised controlled trials ( RCTs ) done in German-speaking Europe are published in international English- language journals and others in national German- language journals . We assessed whether authors are more likely to report trials with statistically significant results in English than in German . METHODS We studied pairs of RCT reports , matched for first author and time of publication , with one report published in German and the other in English . Pairs were identified from reports round in a manual search of five leading German- language journals and from reports published by the same authors in English found on Medline .  Quality of methods and reporting were assessed with two different scales by two investigators who were unaware of authors ' identities , affiliations , and other characteristics of trial reports . Main study endpoints were selected by two investigators who were unaware of trial results . Our main outcome was the number of pairs of studies in which the levels of significance ( shown by p values ) were discordant . FINDINGS 62 eligible pairs of reports were identified but 19 ( 31 % ) were excluded because they were duplicate publications . A further three pairs ( 5 % ) were excluded because no p values were given . The remaining 40 pairs were analysed . Design characteristics and quality features were similar for reports in both language s. Only 35 % of German- language articles , compared with 62 % of English- language articles , reported significant ( p < 0.05 ) differences in the main endpoint between study and control groups ( p = 0.002 by McNemar 's test ) . Logistic regression showed that the only characteristic that predicted publication in an English- language journal was a significant result . The odds ratio for publication of trials with significant results in English was 3.75 ( 95 % CI 1.25 - 11.3 ) . INTERPRETATION Authors were more likely to publish RCTs in an English- language journal if the results were statistically significant . English language bias may , therefore , be introduced in review s and meta-analyses if they include only trials reported in English . The effort of the Cochrane Collaboration to identify as many controlled trials as possible , through the manual search of many medical journals published in different language s will help to reduce such bias BACKGROUND Distinct wheezing disorders co-exist in young ( preschool ) children , some of which ( early transient wheeze and viral wheeze ) are thought to be unrelated to atopy . Investigation of changes in prevalence of wheezing disorders in preschool children could provide important clues about underlying mechanisms responsible for increasing prevalence of asthma in schoolchildren . METHODS Repeated population surveys of the prevalence of respiratory symptoms were done by parent-completed postal question naires in r and om sample s of 1650 ( 1990 ) and 2600 ( 1998 ) caucasian children aged 1 - 5 years living in the county of Leicestershire , UK . FINDINGS The response rates were 86 % ( 1422 of 1650 ) in 1990 and 84 % ( 2127 of 2522 ) in 1998 . Between 1990 and 1998 , there was a significant increase in the prevalance of reported wheeze ever ( 16 % to 29 % , p<0.0001 ) , current wheeze ( 12 % to 26 % , p<0.0001 ) , diagnosis of asthma ( 11 % to 19 % , p<0.0001 ) , treatment for wheeze ( 15 % to 26 % , p<0.0001 ) , and admission for wheeze or other chest trouble ( 6 % to 10 % , p<0.0001 ) . The increase occurred both in children with viral wheeze ( 9 % to 19 % ) and in those with the classic asthma pattern of wheezing with multiple triggers ( 6 % to 10 % ) . There was also an increase in transient early wheezers ( 3 % to 5 % ) , persistent wheezers ( 5 % to 13 % ) , and late-onset wheezers ( 6 % to 8 % ) , and in all severity groups . The increase could not be accounted for by putative household risk factors because these declined between the 2 years . INTERPRETATION The fact that all preschool wheezing disorders increased ( including viral wheeze ) makes it probable that factors unrelated to atopy are implicated in the changing epidemiology of wheeze in childhood The aim of this study was to evaluate the interaction between the exclusive breast-feeding protective effect and the exposure to tobacco smoke at domicile in the first year of life , on the onset of respiratory allergy ( asthma and rhinitis ) in children until 5 yr of age . This is prospect i ve cohort study , observational , institutional based . Three hundred children born in a public hospital of Salvador-Bahia ( Brazil ) were followed from birth to 5 yr of age . Data from 268 children at 60 months of life were analyzed . Occurrence of allergic symptoms were studied and correlated with gender , allergic relatives in first degree , exclusive breast-feeding duration , smoking mother , and presence of other smoker at home , considering the first year of life . Exclusive breast-feeding for at least 6 months showed a protection effect against the onset of respiratory allergy in children from birth to 5 yr ( p < 0.05 ) ; odds ratio ( OR ) : 0.33 ( 95 % CI : 0.18 - 0.59 ) . Breast-fed children for less then 6 months compared with those breast-fed for 6 months or more , presented a higher risk ( OR : 2.34 - 95 % CI : 1.4 - 3.74 ) for developing allergic respiratory symptoms just to 5 yr . The protective effect of exclusive prolonged breast-feeding on the onset of respiratory allergy in children from birth until 5 yr was lost when their mothers were smokers ( OR : 2.50 - 95 % CI 1.19 - 5.19 ) . Therefore , the protective effect of breast-feeding in the first year of life on the onset of allergic symptoms until the age of 5 yr was confirmed . This study proposes a confounding effect of maternal smoking on this protection , exposed by a higher risk for present allergic symptoms until the age of 5 yr , in children exclusively breast-fed for 6 months or more , when their mothers smoked
Asthma and wheezing disorders are common chronic health problems in childhood .
Breastfeeding provides health benefits , but it is not known whether or how breastfeeding decreases the risk of developing asthma .