Low age, low birthweight and congenital heart disease are risk factors for intensive care in infants with bronchiolitis

Aim: This study evaluated the incidence and risk factors for intensive care and respiratory support in infant bronchiolitis. Methods: This retrospective descriptive case-control study focused on 105 patients treated in the paediatric intensive care unit (PICU) and 210 controls treated in the emergency department or on the paediatric ward in Tampere University Hospital in Finland between 2000 and 2015. Statistically significant risk factors in nonadjusted analyses were included in the adjusted logistic regression. Results: The average age-specific annual incidence of bronchiolitis requiring PICU admission under the age of 12 months was 1.5/1000/year (range 0.18-2.59). Independently, significant risk factors for PICU admission were as follows: being less than two months old with an adjusted odds ratio (aOR) of 11.5, birthweight of <2000 g (aOR of 15.9), congenital heart disease (CHD) (aOR of 15.9), apnoea (aOR of 7.2) and the absence of wheezing (aOR of 2.2). Significant risk factors for needing respiratory support were a birthweight of <2000 g, an age of less than two months and CHD. Conclusion: Less than 0.1% of infants under the age of 12 months were admitted to the PICU for bronchiolitis. Low age, low birthweight or prematurity and CHD were independently significant risk factors for both intensive care and respiratory support.