Associations between early life exposure to pollen and adolescent lung function are modified by residential greenness

Abstract

Background: Lung function directly influences metabolic function, stamina and respiratory health. Early life exposures may have a substantial impact on lung development during childhood Objective: To examine the associations between early life ambient grass pollen exposure and lung function up to 18 years and explore potential effect modifications by residential greenness Methods: Using the Melbourne Atopy Cohort Study (MACS), a high-risk allergic disease birth cohort, we examined lung function (FEV1, FVC and FEF25-75) at ages 12 and 18 years. Daily ambient levels of grass pollen (measured with a Burkard trap) and residential greenness levels (derived from satellite imagery) were measured during early life. Instances of URTI before 5 weeks old were collected by parental report Results: Doubling the level of ambient grass pollen a child was exposed to in the first 7 days after birth was associated with a reduction in FVC at both 12 (-16.8mL, 95%CI: -31.9, -1.7) and 18 years (-22.5mL, 95%CI: -44.7, -0.2), after adjustment for levels of residential greenness and URTI before 5 weeks old. Grass pollen exposure in the first 7 days was associated with a reduction in FEV1 at 12 (-13.9mL, 95%CI:-26.9, -1.0), but not 18 years. Associations between quartiles of cumulative grass pollen exposure in the first three months of life and reduced lung function (FEV1, FVC) were stronger in children exposed to high residential greenness (>75%le) in early life (p for interactions Conclusion: Grass pollen exposure in infancy was associated with decreased lung function in children and adolescents, particularly in children living in greener environments