Perinatal Predictors of Wheezing in the First Year of Life a Prospective Study in the South of Brazil

Abstract Introduction: Prematurity has been associated with the occurrence of respiratory symptoms throughout childhood, such as bronchiolitis and pneumonia. The identification of factors related to respiratory morbidity in childhood has direct implications for management and prevention. Objective: Evaluate the perinatal factors associated with wheezing in the first year of life in a prospective cohort of premature babies at a referral maternity hospital in southern Brazil.Methods: This is a prospective cohort of premature babies, less than 37 weeks of gestational age (defined by the Capurro Method or by ultrasound), and non-premature babies. The sample was non-probabilistic and defined by the ability to schedule follow-up appointments at the pulmonology outpatient clinic. The incidence rate for the occurrence of wheezing in the first year was estimated among full-term, premature, and extremely premature babies and adjusted for 1000 babies / year. Results: The number of newborns considered in the final analysis was 138 children (64 premature babies and 74 term babies). Regarding the general characteristics of the mothers, there was a predominance of low education (65.9%), of white ethnicity (79.7%), with an average age of 26 years. During the first year of life, 91 children (65.9%) visited the emergency room and 43 (31.2%) had at least one episode of wheezing. The occurrence of wheezing was 42.6% in male children (p = 0.010) 3). There was a higher percentage of wheezing episodes (35.9%) in preterm infants, especially those younger than 33 weeks (45%); however, this result was not statistically significant (p 0.260). In the multivariate analysis, only the male gender remained associated with the occurrence of wheezing in the first year of life (HR 2.24; 95% CI 1.19-4.21; p 0.012). Conclusions: In this follow-up study, the occurrence of wheezing in preterm infants in the first year of life was high, with twin pregnancy as the main risk factors, the male gender and the use of mechanical ventilation