human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Prematurity ( < 37 weeks ) has been inconsistently associated with  asthma and wheezing .  Chorioamnionitis may promote both prematurity and inflammatory pathways in infants ' airways . OBJECTIVE To investigate the relationship of prematurity and chorioamnionitis with the development of early childhood recurrent wheezing .  METHODS The Boston Birth Cohort ( n = 1096 ) were followed prospect ively from birth to a mean age of 2.2 + /- 2 years . Perinatal and postnatal clinical data and placental pathology were collected . The primary outcome was recurrent wheezing ( > or = 2 physician documented episodes ) . Secondary outcomes included physician-diagnosed asthma , food allergy , and eczema . Preterm children were grouped by gestational age into moderately ( 33 - 36.9 weeks ) and very preterm ( < 33 weeks ) with and without chorioamnionitis , and compared with term children without chorioamnionitis ( reference group ) . Chorioamnionitis was diagnosed either by intrapartum fever or by placental histology findings . Logistic regression models were performed to investigate the independent and joint associations of degree of prematurity and chorioamnionitis . RESULTS Prematurity was associated with recurrent wheezing ( odds ratio [ OR ] , 1.7 ; 95 % CI , 1.2 - 2.6 ) . However , when subjects were grouped by degree of prematurity with or without chorioamnionitis , the highest risk of wheezing ( OR , 4.0 ; 95 % CI , 2.0 - 8.0 ) and physician-diagnosed asthma ( OR , 4.4 ; 95 % CI , 2.2 - 8.7 ) was present in the very preterm children with chorioamnionitis . The effect on both wheezing ( OR , 5.4 ; 95 % CI , 2.4 - 12.0 ) and asthma ( OR , 5.2 ; 95 % CI , 2.3 - 11.9 ) was greater in African Americans . Neither prematurity nor chorioamnionitis was associated with food allergy or eczema . CONCLUSION We found a strong joint effect of prematurity and chorioamnionitis on  early childhood wheezing .  This effect was stronger in African American subjects Objectives : To determine the occurrence of respiratory morbidity during infancy after very premature birth and to identify risk factors . Design : Prospect i ve follow up study . Setting : The United Kingdom oscillation study . Patients : 492 infants , all born before 29 weeks gestation . Interventions : Structured question naires were completed by local paediatricians when the infants were seen in out patients at 6 and 12 months of age corrected for prematurity . Main outcome measures : Cough , wheeze , and treatment requirements and the composite measure of respiratory morbidity ( cough , frequent cough , cough without infection , wheeze , frequent wheeze , wheeze without infection , and use of chest medicine ) and their relation to 13 possible explanatory variables . Results : At 6 and 12 months of corrected age , 27 % of the infants coughed and 6 % had frequent ( more than once a week ) cough , and 20 % and 3 % respectively had wheeze or frequent wheeze . At 6 and 12 months , 14 % of infants had taken bronchodilators and 8 % inhaled steroids . After adjustment for multiple outcome testing , four factors were associated with increased respiratory morbidity : male sex , oxygen dependency at 36 weeks postmenstrual age , having older siblings aged less than 5 years , and living in rented accommodation . Conclusions : Male infants are particularly vulnerable to respiratory morbidity in infancy after very premature birth . It is important to identify a safe and effective strategy to prevent chronic oxygen dependency We investigated whether early lung function abnormalities in prematurely born children with a history of chronic lung disease improve in late childhood and adolescence . We performed a prospect i ve , longitudinal evaluations of pulmonary function over an 8 year period . In seventeen patients from the age ( mean + /- SD ) of 8.2 + /- 1.2 years to the age of 15.1 + /- 1.6 years . They had been born at 29.1 + /- 1.9 weeks of gestation , with a birthweight of 1120 + /- 190 g , and they had received supplemental oxygen , with or without mechanical ventilation , for 40.4 + /- 23.8 days during the neonatal period . They all had radiographic evidence of chronic lung disease at 4 weeks of age . Annual measurements of lung volumes using the helium dilution technique , and of airway function with spirometry and maximal expiratory flow-volume curves over a 5 to 8 year period , were obtained . The results indicated that total lung capacity ( TLC ) and vital capacity ( VC ) were within the predicted normal range in all patients and increased over time . In contrast , the initially abnormal residual volume ( RV ) and RV/TLC ratio decreased over time , suggesting gradual resolution of air-trapping . The peak expiratory flow rate ( PEFR ) , forced expiratory volume in 1 second ( FEV1 ) , and the ratio FEV1/FVC remained at or above the predicted normal range in all patients . FEF25 - 75 , FEF50 , and FEF75 were within normal limits in eight patients and abnormally low ( more than 2 SD below the predicted normal value ) in the remaining nine patients , indicating small airway obstruction . Eight of the nine patients with lower airway obstruction showed significant response to inhaled bronchodilator , and four responded to a histamine challenge . None of the eight patients with normal airway function responded to histamine , but four responded to bronchodilators . The perinatal history , family history of asthma , and exposure to smoking were similar in patients with and without airway obstruction . The height and weight were and remained within the normal range . We conclude that gradual normalization of air-trapping continues well into adolescence in virtually all patients with a history of prematurity and chronic lung disease . in contrast , airflow obstruction may persist but does not get worse later in life . Although chronic airflow obstruction probably is the consequence of injury to the small airways during the neonatal period , it is present in only some of the children , and it does not appear to be directly related to the perinatal history . Finally , there is evidence that airway hyperresponsiveness may be a contributing factor to the development and /or persistence of airflow obstruction in chronic lung disease of prematurity Recurrent respiratory symptoms in the first year of life following preterm delivery were documented in two studies . In the first study a question naire was sent to all parents of preterm very low birth weight ( VLBW ) infants who had been admitted during a six-month period to the Neonatal Intensive Care Unit ( NICU ) at King 's College Hospital ( KCH ) and who lived within the local district . Question naires were also sent to parents of a control group of infants who were recruited by r and om selection . All the controls lived locally and were delivered at KCH in the same six-month period as the study group , but were born at 37 - 41 weeks of gestation and had had no neonatal problems . The question naire documented frequency of cough and wheeze , medication and hospital admissions . Recurrent respiratory symptoms ( wheeze or wheeze and cough ) occurred in 65 % of the preterm VLBW infants but only 33 % of the controls p less than 0.001 . Less than 10 % of infants in either group had received bronchodilator therapy . Admission to hospital in both groups was more common amongst children who had recurrent wheeze ( p less than 0.01 ) . In the second study all preterm VLBW infants admitted to the NICU in a six-month period were followed prospect ively over the first year of life . The nature and frequency of respiratory symptoms and frequency and length of re-admission was documented and related to the duration of neonatal ventilation . Twenty-three of the 44 preterm VLBW infants ( 53 % ) followed prospect ively had recurrent wheeze and /or cough . ( ABSTRACT TRUNCATED AT 250 WORDS Pulmonary function and exercise tolerance were evaluated in late childhood in two groups of prematurely born children : one group with bronchopulmonary dysplasia ( BPD ) [ n = 15 ; gestational age at birth ( GA ) : 29.6 + /- 2.8 weeks ; birth weight ( BW ) : 1,367 + /- 548 g ; age at test : 7.9 + /- 0.6 years ] , and a second group without significant neonatal lung disease [ pre-term ( PT ) ] ( n = 9 ; GA : 30.3 + /- 1.7 weeks ; BW : 1,440 + /- 376 g ; age at test : 7.8 + /- 0.22 years ) . The results were compared with a control group of children of similar ages and heights , born at term [ term born ( TB ) ] . We observed that total lung resistance ( RL ) was significantly higher in BPD ( 11 + /- 3 cmH2O/L/s ) , and in PT ( 9 + /- 2 ) than in TB [ 5 + /- 1 ; ( P < 0.001 and P < 0.05 , respectively ) ] . In BPD RL was higher than in PT ( P < 0.05 ) . Dynamic lung compliance ( CLdyn ) was decreased in BPD ( 43 + /- 11 mL/cmH2O ) and in PT ( 56 + /- 17 ) compared with TB ( 76 + /- 20 ) ( P < 0.001 and P < 0.05 ) , and also in BPD compared with PT ( P < 0.05 ) . Forced expiratory volume in 1 second ( FEV1 ) and FEV1/forced vital capacity ( FVC ) were lower in BPD ( 1.07 + /- 0.15 L and 72 + /- 7 % ) than in PT ( 1.29 + /- 0.23 L , and 80 + /- 7 % ) ( P < 0.05 ) . Exercise tests were performed in six boys with BPD . The ratio between minute ventilation at maximal workload ( VEmax ) and the predicted value of maximal voluntary ventilation ( MVV ) was elevated in the six BPD boys tested , compared with five boys of Group 2 and five TB boys ( 87 + /- 15 % vs. 62 + /- 14 % and 65 + /- 13 % ) ( P < 0.05 ) . We conclude that : 1 ) prematurity and BPD is followed by long-term airway obstruction and a mild degree of exercise intolerance and ; 2 ) premature birth without BPD may be followed by a milder degree of airway obstruction in childhood than in infants who developed BPD during the neonatal period AIMS : To document the prevalence of , and identify risk factors for ,  recurrent wheezing treated with bronchodilators in the first year of life . METHODS : Parental history and neonatal data were collected prospect ively in a regional cohort of very preterm infants ( < 33 weeks ) .  Data on maternal smoking , siblings at home , breast feeding , respiratory symptoms , and hospital re-admissions were documented at 12 months . RESULTS : Outcome data were available for 525/560 ( 95 % ) of survivors . The incidence of recurrent wheeze was 76/525 ( 14.5 % ) in very preterm infants and 20/657 ( 3 % ) in a cohort of term newborns . Significant risk factors for recurrent wheeze in very preterm infants were parental history of asthma , maternal smoking , siblings at home , neonatal oxygen supplementation at 28 days , 36 , and 40 weeks of gestation . CONCLUSIONS : Wheezing respiratory illnesses are common in very preterm infants . The factors involved are similar to those in more mature infants , with the addition of immaturity and neonatal lung injury The objective of this analysis was to examine the effect of low birth weight and prematurity on bronchial air-flow , bronchial reactivity , airway symptoms and asthma diagnosis at school age . A cross-sectional epidemiological study was performed in three small towns in the eastern part of Germany on 2470 school children aged 5 - 14 ( 89.1 % of eligible children ) . A 78 item question naire to determine risk factors at birth and in early childhood was employed . 7.8 % of the children were born before completing 38 gestational weeks ; 6.6 % had a birth weight less than 2500 g.  Pulmonary function analysis were done by a mobile plethysmography at the school . There were only weak restrictions in lung volume in term low birth weight ( LBW ) children ( 100 ml lower TLC , p = 0.107 ) , and flow ( 257 ml lower PEFR , p = 0.108 ) , were low . However , bronchial hyper-responsiveness indicated by 292 ml lower FEV1.0 after cold air bronchial provocation , was significantly increased compared to term normal birth weight children ( p < 0.001 ) . The effect of LBW was less in older children , only slightly stronger in girls and increased in children mechanically ventilated during the postnatal period . Correspondingly , there was a higher prevalence of diagnosed asthma in term LBW children ( OR 1.6 , 95%-confidence interval 1.0 - 2.6 ) , however these were without an increased risk for any allergic sensitization . LBW , therefore , seems to be a risk factor for smaller lungs and hyperreactive airways primarily in term 
    Output:
    
agent
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Prematurity ( < 37 weeks ) has been inconsistently associated with  asthma and wheezing .  Chorioamnionitis may promote both prematurity and inflammatory pathways in infants ' airways . OBJECTIVE To investigate the relationship of prematurity and chorioamnionitis with the development of early childhood recurrent wheezing .  METHODS The Boston Birth Cohort ( n = 1096 ) were followed prospect ively from birth to a mean age of 2.2 + /- 2 years . Perinatal and postnatal clinical data and placental pathology were collected . The primary outcome was recurrent wheezing ( > or = 2 physician documented episodes ) . Secondary outcomes included physician-diagnosed asthma , food allergy , and eczema . Preterm children were grouped by gestational age into moderately ( 33 - 36.9 weeks ) and very preterm ( < 33 weeks ) with and without chorioamnionitis , and compared with term children without chorioamnionitis ( reference group ) . Chorioamnionitis was diagnosed either by intrapartum fever or by placental histology findings . Logistic regression models were performed to investigate the independent and joint associations of degree of prematurity and chorioamnionitis . RESULTS Prematurity was associated with recurrent wheezing ( odds ratio [ OR ] , 1.7 ; 95 % CI , 1.2 - 2.6 ) . However , when subjects were grouped by degree of prematurity with or without chorioamnionitis , the highest risk of wheezing ( OR , 4.0 ; 95 % CI , 2.0 - 8.0 ) and physician-diagnosed asthma ( OR , 4.4 ; 95 % CI , 2.2 - 8.7 ) was present in the very preterm children with chorioamnionitis . The effect on both wheezing ( OR , 5.4 ; 95 % CI , 2.4 - 12.0 ) and asthma ( OR , 5.2 ; 95 % CI , 2.3 - 11.9 ) was greater in African Americans . Neither prematurity nor chorioamnionitis was associated with food allergy or eczema . CONCLUSION We found a strong joint effect of prematurity and chorioamnionitis on  early childhood wheezing .  This effect was stronger in African American subjects Objectives : To determine the occurrence of respiratory morbidity during infancy after very premature birth and to identify risk factors . Design : Prospect i ve follow up study . Setting : The United Kingdom oscillation study . Patients : 492 infants , all born before 29 weeks gestation . Interventions : Structured question naires were completed by local paediatricians when the infants were seen in out patients at 6 and 12 months of age corrected for prematurity . Main outcome measures : Cough , wheeze , and treatment requirements and the composite measure of respiratory morbidity ( cough , frequent cough , cough without infection , wheeze , frequent wheeze , wheeze without infection , and use of chest medicine ) and their relation to 13 possible explanatory variables . Results : At 6 and 12 months of corrected age , 27 % of the infants coughed and 6 % had frequent ( more than once a week ) cough , and 20 % and 3 % respectively had wheeze or frequent wheeze . At 6 and 12 months , 14 % of infants had taken bronchodilators and 8 % inhaled steroids . After adjustment for multiple outcome testing , four factors were associated with increased respiratory morbidity : male sex , oxygen dependency at 36 weeks postmenstrual age , having older siblings aged less than 5 years , and living in rented accommodation . Conclusions : Male infants are particularly vulnerable to respiratory morbidity in infancy after very premature birth . It is important to identify a safe and effective strategy to prevent chronic oxygen dependency We investigated whether early lung function abnormalities in prematurely born children with a history of chronic lung disease improve in late childhood and adolescence . We performed a prospect i ve , longitudinal evaluations of pulmonary function over an 8 year period . In seventeen patients from the age ( mean + /- SD ) of 8.2 + /- 1.2 years to the age of 15.1 + /- 1.6 years . They had been born at 29.1 + /- 1.9 weeks of gestation , with a birthweight of 1120 + /- 190 g , and they had received supplemental oxygen , with or without mechanical ventilation , for 40.4 + /- 23.8 days during the neonatal period . They all had radiographic evidence of chronic lung disease at 4 weeks of age . Annual measurements of lung volumes using the helium dilution technique , and of airway function with spirometry and maximal expiratory flow-volume curves over a 5 to 8 year period , were obtained . The results indicated that total lung capacity ( TLC ) and vital capacity ( VC ) were within the predicted normal range in all patients and increased over time . In contrast , the initially abnormal residual volume ( RV ) and RV/TLC ratio decreased over time , suggesting gradual resolution of air-trapping . The peak expiratory flow rate ( PEFR ) , forced expiratory volume in 1 second ( FEV1 ) , and the ratio FEV1/FVC remained at or above the predicted normal range in all patients . FEF25 - 75 , FEF50 , and FEF75 were within normal limits in eight patients and abnormally low ( more than 2 SD below the predicted normal value ) in the remaining nine patients , indicating small airway obstruction . Eight of the nine patients with lower airway obstruction showed significant response to inhaled bronchodilator , and four responded to a histamine challenge . None of the eight patients with normal airway function responded to histamine , but four responded to bronchodilators . The perinatal history , family history of asthma , and exposure to smoking were similar in patients with and without airway obstruction . The height and weight were and remained within the normal range . We conclude that gradual normalization of air-trapping continues well into adolescence in virtually all patients with a history of prematurity and chronic lung disease . in contrast , airflow obstruction may persist but does not get worse later in life . Although chronic airflow obstruction probably is the consequence of injury to the small airways during the neonatal period , it is present in only some of the children , and it does not appear to be directly related to the perinatal history . Finally , there is evidence that airway hyperresponsiveness may be a contributing factor to the development and /or persistence of airflow obstruction in chronic lung disease of prematurity Recurrent respiratory symptoms in the first year of life following preterm delivery were documented in two studies . In the first study a question naire was sent to all parents of preterm very low birth weight ( VLBW ) infants who had been admitted during a six-month period to the Neonatal Intensive Care Unit ( NICU ) at King 's College Hospital ( KCH ) and who lived within the local district . Question naires were also sent to parents of a control group of infants who were recruited by r and om selection . All the controls lived locally and were delivered at KCH in the same six-month period as the study group , but were born at 37 - 41 weeks of gestation and had had no neonatal problems . The question naire documented frequency of cough and wheeze , medication and hospital admissions . Recurrent respiratory symptoms ( wheeze or wheeze and cough ) occurred in 65 % of the preterm VLBW infants but only 33 % of the controls p less than 0.001 . Less than 10 % of infants in either group had received bronchodilator therapy . Admission to hospital in both groups was more common amongst children who had recurrent wheeze ( p less than 0.01 ) . In the second study all preterm VLBW infants admitted to the NICU in a six-month period were followed prospect ively over the first year of life . The nature and frequency of respiratory symptoms and frequency and length of re-admission was documented and related to the duration of neonatal ventilation . Twenty-three of the 44 preterm VLBW infants ( 53 % ) followed prospect ively had recurrent wheeze and /or cough . ( ABSTRACT TRUNCATED AT 250 WORDS Pulmonary function and exercise tolerance were evaluated in late childhood in two groups of prematurely born children : one group with bronchopulmonary dysplasia ( BPD ) [ n = 15 ; gestational age at birth ( GA ) : 29.6 + /- 2.8 weeks ; birth weight ( BW ) : 1,367 + /- 548 g ; age at test : 7.9 + /- 0.6 years ] , and a second group without significant neonatal lung disease [ pre-term ( PT ) ] ( n = 9 ; GA : 30.3 + /- 1.7 weeks ; BW : 1,440 + /- 376 g ; age at test : 7.8 + /- 0.22 years ) . The results were compared with a control group of children of similar ages and heights , born at term [ term born ( TB ) ] . We observed that total lung resistance ( RL ) was significantly higher in BPD ( 11 + /- 3 cmH2O/L/s ) , and in PT ( 9 + /- 2 ) than in TB [ 5 + /- 1 ; ( P < 0.001 and P < 0.05 , respectively ) ] . In BPD RL was higher than in PT ( P < 0.05 ) . Dynamic lung compliance ( CLdyn ) was decreased in BPD ( 43 + /- 11 mL/cmH2O ) and in PT ( 56 + /- 17 ) compared with TB ( 76 + /- 20 ) ( P < 0.001 and P < 0.05 ) , and also in BPD compared with PT ( P < 0.05 ) . Forced expiratory volume in 1 second ( FEV1 ) and FEV1/forced vital capacity ( FVC ) were lower in BPD ( 1.07 + /- 0.15 L and 72 + /- 7 % ) than in PT ( 1.29 + /- 0.23 L , and 80 + /- 7 % ) ( P < 0.05 ) . Exercise tests were performed in six boys with BPD . The ratio between minute ventilation at maximal workload ( VEmax ) and the predicted value of maximal voluntary ventilation ( MVV ) was elevated in the six BPD boys tested , compared with five boys of Group 2 and five TB boys ( 87 + /- 15 % vs. 62 + /- 14 % and 65 + /- 13 % ) ( P < 0.05 ) . We conclude that : 1 ) prematurity and BPD is followed by long-term airway obstruction and a mild degree of exercise intolerance and ; 2 ) premature birth without BPD may be followed by a milder degree of airway obstruction in childhood than in infants who developed BPD during the neonatal period AIMS : To document the prevalence of , and identify risk factors for ,  recurrent wheezing treated with bronchodilators in the first year of life . METHODS : Parental history and neonatal data were collected prospect ively in a regional cohort of very preterm infants ( < 33 weeks ) .  Data on maternal smoking , siblings at home , breast feeding , respiratory symptoms , and hospital re-admissions were documented at 12 months . RESULTS : Outcome data were available for 525/560 ( 95 % ) of survivors . The incidence of recurrent wheeze was 76/525 ( 14.5 % ) in very preterm infants and 20/657 ( 3 % ) in a cohort of term newborns . Significant risk factors for recurrent wheeze in very preterm infants were parental history of asthma , maternal smoking , siblings at home , neonatal oxygen supplementation at 28 days , 36 , and 40 weeks of gestation . CONCLUSIONS : Wheezing respiratory illnesses are common in very preterm infants . The factors involved are similar to those in more mature infants , with the addition of immaturity and neonatal lung injury The objective of this analysis was to examine the effect of low birth weight and prematurity on bronchial air-flow , bronchial reactivity , airway symptoms and asthma diagnosis at school age . A cross-sectional epidemiological study was performed in three small towns in the eastern part of Germany on 2470 school children aged 5 - 14 ( 89.1 % of eligible children ) . A 78 item question naire to determine risk factors at birth and in early childhood was employed . 7.8 % of the children were born before completing 38 gestational weeks ; 6.6 % had a birth weight less than 2500 g.  Pulmonary function analysis were done by a mobile plethysmography at the school . There were only weak restrictions in lung volume in term low birth weight ( LBW ) children ( 100 ml lower TLC , p = 0.107 ) , and flow ( 257 ml lower PEFR , p = 0.108 ) , were low . However , bronchial hyper-responsiveness indicated by 292 ml lower FEV1.0 after cold air bronchial provocation , was significantly increased compared to term normal birth weight children ( p < 0.001 ) . The effect of LBW was less in older children , only slightly stronger in girls and increased in children mechanically ventilated during the postnatal period . Correspondingly , there was a higher prevalence of diagnosed asthma in term LBW children ( OR 1.6 , 95%-confidence interval 1.0 - 2.6 ) , however these were without an increased risk for any allergic sensitization . LBW , therefore , seems to be a risk factor for smaller lungs and hyperreactive airways primarily in term 
    Output:
    