Breastfeeding and family history of atopy as predictors of clinical course for acute uncomplicated bronchiolitis in infants: a prospective, longitudinal, cohort study.

Background: Acute bronchiolitis (AB) is the most common lower airway disease in infants. The high incidence of this pathology and the risk of severe complications make it necessary to identify prognostic factors. The aim of this study was to determine whether there is an association between a family history of atopy and breastfeeding for more than six months and clinical outcomes in patients with AB. Methods: This was a prospective, longitudinal cohort study. Patients who visited the emergency department of the General Hospital of Cuautitlán from October 1, 2020, to January 31, 2021 were included. Data collection was performed by means of a questionnaire with open-ended questions. Oxygen saturation data were collected at admission at 6, 12, 24, 24, 48, 72 and 120 hours. Results: A sample of 108 participants was analyzed. We found a decrease of -3.69% (p=0.005, 95% CI: -6.24, -1.14) in oxygen saturation at admission in participants with a history of paternal atopy and an increased risk for hospitalization. Breastfeeding increased SaO2 by 2.41% (p=0.001, 95% CI: 1.02, 3.81) but was also a protective factor against hospitalization (OR=0.13, p=0.001 95% CI: 0.041 - 0.44). Conclusions: A history of paternal atopy is a poor prognostic factor for the clinical course of AB. Breastfeeding proved to be a protective factor.