High baseline prevalence of atopic comorbidities and medication use in children treated with allergy immunotherapy in the REAl-world effeCtiveness in allergy immunoTherapy (REACT) study

Abstract

Background: Respiratory allergy, commonly manifesting as allergic rhinitis (AR) and asthma, is a chronic progressive disease that frequently starts in childhood. Allergy immunotherapy (AIT) is the only causal treatment for respiratory allergy with the potential to modify the underlying cause of allergy and, ultimately, prevent disease progression. This analysis aimed to determine if AIT is received sufficiently early to halt the progression of allergic disease, by characterizing the burden and progression of disease in children prior to AIT initiation in real-life clinical practice.

Methods: The REAl-world effeCtiveness in allergy immunoTherapy (REACT) study was a large retrospective cohort study using German claims data between 2007 and 2017. Characteristics of two pre-defined AIT age cohorts from the REACT study - children (aged <18 years) and adults (aged ≥18 years) - were evaluated during the 1-year period before the first AIT prescription. For comparison, a control group of all subjects with a confirmed diagnosis of AR and without prescriptions for AIT was included. Burden of disease was assessed using diagnostic codes for atopic comorbidities [e.g., atopic dermatitis (AD), asthma, and acute allergic conjunctivitis] and non-atopic comorbidities (e.g., migraine, headache); medication use, recorded as prescriptions for symptom-relieving AR medication and reliever/controller medication for asthma, was also assessed. Data were analyzed descriptively, using summary statistics.

Results: Both children (n = 11,036) and adults (n = 30,037) showed a higher prevalence of atopic comorbidities and a greater drug burden prior to AIT initiation compared to AR patients not treated with AIT (n = 1,003,332). In the two age-specific AIT cohorts, children consistently showed the highest prevalence of atopic comorbidities compared to adults (AIT children, AIT adults - asthma: 41.4%, 34.5%; AD: 19.9%, 10.2%; acute allergic conjunctivitis: 13.6%, 10.2%). Generally, prescriptions per year for symptom-relieving AR and asthma treatments were also higher for children initiating AIT vs. adults (AIT children, AIT adults - AR prescriptions per subject: 1.72, 0.73; asthma prescriptions per subject: 1.42, 0.79).

Conclusions: Children with AR who are offered AIT in real-life show considerable disease burden prior to initiation. As AIT may alleviate the burden and halt the progression of allergic disease, considering AIT earlier in the disease course may be warranted.

Keywords: Allergic rhinitis; allergy immunotherapy; asthma; atopic comorbidities; atopic dermatitis; disease burden; pediatric; real-world evidence (RWE).

Figure 1

Subject selection in the main REACT study (2007–2017). Data are adapted from the main publication (47). The AIT age cohorts were formed by re-matching subjects from the main cohort, by age. AIT subjects who could not find a match were excluded from the cohorts. In addition to the children and adults in the AIT group, the entire group of subjects diagnosed with AR and without prescriptions for AIT were included as controls. AIT, allergy immunotherapy; AR, allergic rhinitis; REACT, REAl-world effeCtiveness in allergy immunoTherapy.

Figure 2

Prevalence of key atopic comorbidities in subjects with AR. Data presented are from the 1-year period before the index date (i.e., the first prescription for AIT during the study period) for children and adults in the AIT group, and for control subjects (i.e., all AR subjects without prescriptions for AIT) (published previously) (47). Asthma was defined based on the ICD-10 diagnostic code J45.x, or J46 and/or at least two prescriptions of SABA/ICS within an index year. AD and acute allergic conjunctivitis were defined according to the ICD-10 diagnostic codes L20–L20.9 and H10.1, respectively. AIT, allergy immunotherapy; AR, allergic rhinitis; ICD-10, International Statistical Classification of Diseases and Related Health Problems 10th Revision; ICS, inhaled corticosteroid; SABA, short-acting beta agonist.

Figure 3

Prevalence of comorbidities in subjects with AR who had received AIT prescriptions. Data presented are from the 1-year period before the index date (i.e., the first prescription for AIT during the study period) for subjects in the AIT group. ICD-10 diagnostic codes – asthma: J45.x, J46; bronchitis: J20.x, J40.x–J42, J44.x; pneumonia: J12.x–J18.x; chronic cough: R05; viral illness pharyngitis: J10.1, B00.2, B08.5, B08.8, B27.x; otitis media: H65.x–H67.x; Eustachian tube dysfunction: H68.1–H69.x; conjunctivitis: H10.x; eczema: L20.x–L30.x, L50.x–L54.x; skin rash: R21; eosinophilic esophagitis: K20; GERD: K21.x; sleep apnea: G47.3; sleep disturbance: G47.0–G47.2, F51.x; ADD: F90.x; migraine: G43.x; headache: R51, G44.x; depression: F32.x–F33.x. ADD, attention deficit disorder; AIT, allergy immunotherapy; CNS, central nervous system; GERD, gastroesophageal reflux disorder; GI, gastrointestinal; ICD-10, International Statistical Classification of Diseases and Related Health Problems 10th Revision.

Figure 4

Medication use for AR (A) and asthma (B). Data presented are from the 1-year period before the index date (i.e., the first prescription for AIT during the study period) for children and adults in the AIT group, and for control subjects (i.e., all AR subjects without prescriptions for AIT) (47). The “All AR prescriptions” and “All asthma prescriptions” data for AR subjects without AIT have been published previously (47). AIT, allergy immunotherapy; AR, allergic rhinitis; ICS, inhaled corticosteroid; INCS, intranasal corticosteroid; LABA, long-acting beta agonist; SABA, short-acting beta agonist.