Factors associated with mild bronchiolitis in young infants

Area of Science:

• Pediatrics
• Respiratory Medicine
• Epidemiology

Background:

• Bronchiolitis in early infancy (first 3 months) is a risk factor for severe illness.
• Identifying mild cases in infants under 90 days is crucial for appropriate care and resource allocation.

Purpose of the Study:

• To identify clinical characteristics associated with mild bronchiolitis in infants 90 days or younger presenting to the emergency department (ED).

Main Methods:

• Secondary analysis of a prospective cohort study involving infants 90 days or younger with clinically diagnosed bronchiolitis.
• Mild bronchiolitis defined by discharge from ED without subsequent hospitalization or brief (<24 hours) inpatient stay.
• Multivariable logistic regression used to determine factors associated with mild illness.

Main Results:

• Of 333 eligible infants (≤90 days), 47% experienced mild bronchiolitis; none required mechanical ventilation.
• Older age (61-90 days vs. 0-60 days) was associated with mild bronchiolitis (OR 2.72).
• Adequate oral intake (OR 4.48) and lowest ED oxygen saturation ≥94% (OR 3.12) were also significantly associated with mild illness.

Conclusions:

• Approximately half of infants aged 90 days or younger presenting to the ED with bronchiolitis had a mild course.
• Older age, adequate oral intake, and higher oxygen saturation are key predictors of mild bronchiolitis in this age group.
• These findings can inform strategies to reduce unnecessary hospitalizations for young infants with bronchiolitis.