ObjectiveTo determine the association of urbanicity, defined as living in an urban area, with cognitive development at five years of age in preterm children who were free of any disabilities or neurodevelopmental delays.DesignProspective population-based cohort.SettingFrench regional Loire Infant Follow-up Team (LIFT) network.ParticipantsIncluded in the study were 1738 surviving infants born between March 2003 and December 2008 before 35 weeks of gestational age. At two years of age, the children were free of any disabilities and neurodevelopmental delays and were living in the Pays de la Loire region from their birth to five years of age.Main Outcome MeasuresThe cognitive development at five years of age was evaluated with the Global School Adaptation score (GSA). The urbanicity of the residence for each child was classified into three groups: urban, quasi-rural, and rural area.ResultsQuantile regression approaches were used to identify a significant association between urbanicity and the GSA score at five years of age (adjusting for child and family characteristics). We found that the negative impact of urbanicity on the GSA score was more important for the lower quantile of the GSA scores.ConclusionsUrbanicity was significantly associated with cognitive neurodevelopment at five years of age in preterm children born before 35 weeks of gestation. Complementary results additionally suggest that this relation could be mediated at the residence level by a high socioeconomic deprivation level. If these results are confirmed, more personalized follow-ups could be developed for preterm children. Further studies are needed to finely identify the contextual characteristics of urbanicity that underlie this association.

Preterm infants are at greater risk of bronchopulmonary dysplasia, which is associated with neurodevelopmental impairment. These infants are also more likely to develop severe bronchiolitis, which can contribute to neurodevelopmental impairment. The aim of this study was to determine whether severe bronchiolitis in very preterm infants (born before 33 weeks of gestation) was associated with an increased risk of neurodevelopmental impairment at 2 years of age. We analyzed a population-based cohort of infants (the Loire Infant Follow-up Team cohort) born between 1 January 2003 and 31 December 2009. Severe bronchiolitis was defined as hospitalization due to bronchiolitis during the first year of life. Neurodevelopmental outcome was assessed at 2 years of corrected age. A total of 2,405 infants were included in this analysis and categorized based on neonatal respiratory status: 1,308 (54.4 %) received no respiratory assistance, 864(35.9 %) received oxygen for <28 days, and 167 (6.9 %) had mild and 66 (2.7) moderate or severe bronchopulmonary dysplasia. At 2 years, 502 children displayed non-optimal neurodevelopmental outcome (20.9 %). Moderate or severe bronchopulmonary dysplasia was significantly associated with non-optimal neurodevelopmental outcome at 2 years (adjusted odds ratios (OR) = 2.3 [95 % confidence interval (CI): 1.3-3.9], p = 0.003). In the first year, 318 infants acquired severe bronchiolitis (13.2 %), which was not associated with non-optimal neurodevelopmental outcome (adjusted OR = 1.0 [95 % CI: 0.8-1.4]; p = 0.88). In conclusion, respiratory status in the neonatal period was significantly associated with non-optimal neurodevelopmental outcome at 2 years, while severe bronchiolitis was not.