Things We Do for No Reason: Systemic Corticosteroids for Wheezing in Preschool-Aged Children

Some data suggest that there may be clinical benefit from treatment with SCS in preschool children who wheeze. A recent trial by Foster et al. included 605 children, aged 24-72 months, presenting to a pediatric ED with wheeze plus viral upper respiratory symptoms.¹¹ Patients were randomized to receive a three-day course of prednisolone (1 mg/kg) or placebo. The primary outcome was length of hospital stay until ready for discharge, which they found was significantly longer for placebo-treated patients (540 minutes) versus prednisolone (370 minutes).

There are few randomized controlled trials evaluating the efficacy of SCS in preschool-aged children with viral-induced wheezing, and these children are often grouped with younger or older children in studies. While limited in number, these studies have evaluated SCS efficacy with acute wheezing in preschool-aged children in outpatient, ED, and inpatient settings (Appendix Table).^12-16 The majority of trials of SCS in this age group have shown mixed or negative results.

Admission rates for preschoolers with viral wheezing were not statistically different in those receiving oral prednisolone versus placebo in a study conducted by Oomen et al. evaluating outpatient, parent-initiated prednisolone.¹⁴ Tal et al. found overall benefit with reduced admission rate for patients treated in the ED with methylprednisolone versus placebo; however, this finding was not statistically significant in patients 24-54 months old.¹⁶

For those requiring hospitalization, length of hospital stay and time until readiness to discharge were the primary outcomes assessed by Panickar et al. and Jartti et al. Neither study found a statistically significant difference between groups who received oral prednisolone versus placebo for 3 or 5 days. Secondary outcomes such as symptom scores, symptom duration, albuterol use, and 60-day relapse rate were also not improved in those taking oral prednisolone compared with placebo.^14,15

The mixed results of studies assessing the efficacy of SCS in preschool-aged wheezing children may be attributed to the fact that wheezing in this age group likely represents multiple underlying processes. Most acute wheezing at this age is not associated with atopy and is often triggered by viral respiratory tract infections.¹⁷ Furthermore, 90% of wheezing in children under the age of five years does not persist to the asthma phenotype (recurrent episodes with multiple triggers, airway obstruction, and hyper-responsiveness) once they reach school age.¹⁸

While SCS are generally not expensive, their use is not without cost. Studies of oral corticosteroid use in children with asthma have shown adverse effects including vomiting, hypertension, and impaired growth.¹⁹ Children with recurrent wheeze receiving SCS may demonstrate biochemical hypothalamic-pituitary-axis dysfunction.²⁰ Given the high utilization and SCS prescription rates in this age group, reducing the use of SCS with wheezing episodes could have a large clinical and financial impact.^3,4 These medications should be used judiciously in order to balance benefit with potential risks.

Given that there is diversity in the phenotype of preschool-aged children who wheeze, it is possible that a subset of these children would benefit from SCS. Some studies have shown that certain groups of patients derive benefit, including those with rhinovirus infection, eczema, and children at higher risk for multitrigger asthma.^11,13 Children who have atopic wheeze are more likely to have persistent symptoms that may eventually be diagnosed as asthma.¹⁸ These children will have airway inflammation secondary to eosinophilic infiltration and may be responsive to SCS at times of exacerbation. However, attempts to classify preschool children based on risk of asthma have not shown consistent results.