<p>Impact of Prematurity and Severe Viral Bronchiolitis on Asthma Development at 6–9 Years</p>

Abstract

Background Premature birth is associated with increased susceptibility for viral infections and chronic airway morbidity. Preterm children, even moderate and late, may be at risk for short- and long-term respiratory morbidities. Objective Our main goal was to compare the burden of two conditions, severe bronchiolitis and prematurity (early and moderate-late), on asthma development at 6–9 years. Patients and Methods A retrospective cohort of all preterm (<37weeks gestational age) and full-term children hospitalized for bronchiolitis, with current age between 6 and 9 years, was created. A second cohort was made up of preterm children, without admission for bronchiolitis, randomly chosen from the hospital premature births database. Prevalence and risk factors for asthma were analysed. Parents completed the International Study of Asthma and Allergies in Childhood (ISAAC) Questionnaire for asthma symptoms for children 6–7 years. Lung function and aeroallergen sensitization were evaluated. Results Of the 480 selected children, 399 could be contacted and agreed to participate: 133 preterm and 114 full-term cases with admission for bronchiolitis and 146 preterm control children without admission for bronchiolitis. The frequency of current asthma at 6–9 years was higher in preterm cases (27%) compared with full-term-cases (15%) and preterm controls (14%) (p=0.04). Among hospitalized-bronchiolitis children, prematurity (p=0.04), rhinovirus infection (p=0.03), viral coinfection (p=0.04) and paternal asthma (p=0.003) were risk factors for asthma at 6–9 years. Among premature children, with and without bronchiolitis admission, the risk factors for asthma at 6–9 years were admission for bronchiolitis (p=0.03) and aeroallergen sensitisation (p=0.01). Moderate and late preterm children without admission for bronchiolitis showed similar prevalence of current asthma than full-term ones, previously admitted for bronchiolitis. Conclusion Preterm birth is an important early life risk factor for asthma in childhood. The addition of other risk factors, such as severe bronchiolitis, especially by rhinovirus or viral coinfections, are associated with even higher risk for subsequent asthma.

Bronchopulmonary dysplasia as a determinant of respiratory outcomes in adult life

“…Children hospitalized for RSV in early life have also been reported to have a higher risk for developing recurrent wheezing 61 . In a retrospective study, it was shown that preterm infants hospitalized with bronchiolitis were more likely to have asthma at 6–9 years of age 62 . Aeroallergen sensitization was another risk factor for asthma in this study.…”

Impact of breastfeeding on the incidence and severity of respiratory syncytial virus (RSV)-associated acute lower respiratory infections in infants: a systematic review highlighting the global relevance of primary prevention

“…Hospitalisation with a confirmed RSV-associated ALRI in preterm infants was associated with more than twice the risk of acquiring long-term respiratory morbidity, such as asthma. 60 More research needs to be conducted to determine the optimal duration of exclusive breastfeeding and if partial breastfeeding provides adequate protection against RSV-associated ALRI.…”

“…Reflecting on available evidence, it is clear that without passive immunity delivered by MOM at birth, infants with underdeveloped immune systems are subjected to more severe disease outcomes. Hospitalisation with a confirmed RSV-associated ALRI in preterm infants was associated with more than twice the risk of acquiring long-term respiratory morbidity, such as asthma 60. More research needs to be conducted to determine the optimal duration of exclusive breastfeeding and if partial breastfeeding provides adequate protection against RSV-associated ALRI.…”

Childhood asthma: pathogenesis and phenotypes

“…This increased risk of asthma after preterm birth continues into middle-age [86]. Additionally, preterm-born children are at increased risk of severe bronchiolitis with RSV or rhinovirus, infections that may further increase the risk of subsequent asthma [87,88]. The mechanisms underlying the increased risk on lower lung function and asthma development in premature-born children are not fully understood.…”