Severe asthma in children: Description of a large multidisciplinary clinical cohort

Abstract

Background: Children with severe asthma have substantial morbidity and healthcare utilization. Pediatric severe asthma is a heterogeneous disease, and a multidisciplinary approach can improve the diagnosis and management of these children.

Methods: We reviewed the electronic health records for patients seen in the Severe Asthma Clinic (SAC) at UPMC Children's Hospital of Pittsburgh between August 2012 and October 2019.

Results: Of the 110 patients in whom we extracted data, 46% were female, 48% were Black/African American, and 41% had ≥1 admission to the pediatric intensive care unit (PICU) for asthma. Compared to patients without a PICU admission, those with ≥1 PICU admission were more likely to be non-White (64.4% vs. 41.5%, p = 0.031) and more atopic (eosinophil count geometric mean = 673 vs. 319 cells/mm³ , p = 0.002; total IgE geometric mean = 754 vs. 303 KU/L, p = 0.003), and to have lower pre-bronchodilator FEV1 (58.6% [±18.1%] vs. 69.9% [±18.7%], p = 0.002) and elevated FeNO (60% vs. 22%, p = 0.02). In this cohort, 84% of patients were prescribed high-dose ICS/LABA and 36% were on biologics. Following enrollment in the SAC, severe exacerbations decreased from 3.2/year to 2.2/year (p < 0.0001); compared to the year before joining the SAC, in the following year the group had 106 fewer severe exacerbations.

Conclusions: This large cohort of children with severe asthma had a high level of morbidity and healthcare utilization. Patients with a history of PICU admissions for asthma were more likely to be nonwhite and highly atopic, and to have lower lung function. Our data support a positive impact of a multidisciplinary clinic on patients with severe childhood asthma.

Keywords: multidisciplinary clinic; severe asthma; severe childhood asthma.

Figure 1 –. Baseline lung function of Severe Asthma Clinic (SAC) cohort

Figure shows the baseline lowest FEV1 as percent-of-predicted (FEV1pp) upon clinic entry, before and after bronchodilator administration. Bronchodilator response (BDR) defined as percent change from pre-bronchodilator FEV1.

Figure 2 –. Atopy biomarkers in SAC cohort

Eosinophil counts (cells/μL) and total IgE (IU/mL) were highly skewed, as seen in the figure, and therefore were log10-transformed for analysis. Results in the text are reported as medians and interquartile ranges (IQR) or as geometric means.

Figure 3 –. Change in annual rate of severe asthma exacerbations

Numbers represent the difference in severe asthma exacerbations between the year after joining the SAC, and the average of the two years prior to joining the clinic (e.g., −5 means the patient had 5 fewer events in the year after their index clinic visit, compared to the average of the two years before that date).