Respiratory infections in infancy are associated with pre-school asthma

Respiratory infections in infancy are associated with preschool asthma Intro: Respiratory infection(RI) may increase the risk of respiratory morbidity in later life, however the association between infant RI and respiratory disease is not well understood. Using data from the CHILD Cohort Study(n=2364), we sought to determine whether RIs in the first 12 months of life are associated with preschool asthma. Methods: Data on RI was collected at birth to 1 year of age from parent questionnaires. RI was defined as a cold plus fever, and ≥1 of: cough, chest congestion, trouble breathing, stuffy, or runny nose in the last 3/6 months. RIs were further classified as lower tract (LRTI), characterized by cough, congestion or trouble breathing. Or, as upper tract (URTI), characterized by stuffy/runny nose only. Asthma diagnosis at age 5 was based on study physician assessments. Logistic regression was used to examine associations of RI timing (0-3,3-6,6-12m), RI type (URTI, LRTI) and asthma at age 5. Results: Of those with asthma at age 5, 11.3%and 48.5% had an RI between birth and 3m and between 6 and 12m, respectively, compared to non-asthmatics(6.9%and 40.1%). A LRTI between birth and 3m was associated with a 90% increased risk of asthma at age 5 (OR 1.9,95%CI 0.99,3.37, p=0.04). Similarly, an LRTI between 6 and 12m was associated with a 55% increase in odds of asthma diagnosis at age 5 (OR 1.55,95%CI 1.07,2.25, p=0.02). Conclusion: Our preliminary analysis suggests that infant RIs are associated with preschool asthma, and that LRTIs in the first 3m of life may have a higher associated risk than URTIs. Further work is needed to determine if this association extends to objective clinical measures of preschool asthma, like PFTs.