Impact of AIT on Allergic Rhinitis and Asthma

Study Overview
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Brief Summary
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The study will assess the effectiveness of AIT treatment in real clinical practice in Germany.

Detailed Description
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Allergic rhinitis (AR) affects 23-30% of the European population and is associated with a major burden on public health. AR and asthma frequently coexist, and may both be caused by allergen exposure. While the efficacy of AIT, i.e. reduce symptoms and medication use in patients with AR and asthma, has been demonstrated in several randomized clinical trials, little is known about the use and effectiveness of AIT in real world clinical practice. This study is a retrospective database study that uses real-world data from Germany. The study population consists of AR patients with and without asthma treated with AIT and matched controls not treated with AIT. Information about the patients and treatments will be obtained from the 'BKK German Sickness Fund Database' from 2007 until 2017.

Official Title
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Impact of AIT on Allergic Rhinitis and Asthma Using Real World Evidence

Conditions
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Allergy, Respiratory Disease

Intervention / Treatment
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* Drug: Allergy immunotherapy (AIT)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria for the AIT cohort: At least two index-AIT prescriptions during the first FU-year At least one confirmed AR diagnosis during the study period Continuous enrollment (no gaps in insurance time-defined by days) for 12 months before the index event (in the pre-index period) Continuous enrollment (no gaps in insurance time-defined by days) for at least 12 months after the index event (in the post-index period) Inclusion Criteria for the Control Cohort: - For the control groups, the same inclusion criteria will apply, with the exception of inclusion criterion 1, i.e. controls have not received AIT before baseline. Exclusion Criteria: - AIT prescription 12 months before the index event (in the pre-index period) for the AIT treatment group
Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| AIT Cohort<br>Allergic rhinitis patients with and without asthma treated with AIT | Drug: Allergy immunotherapy (AIT)<br>* Immunotherapy for different types of allergies<br>|
| Control Cohort<br>Allergic rhinitis patients with and without asthma not treated with AIT | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Allergic rhinitis medication use | Number of patients with an AR prescription and number of prescriptions by drug class | From pre-index year to follow-up year(s), assessed from 2007 and up to 2017 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Asthma medication use | Number of patients with an asthma prescription and number of prescriptions by drug class | From pre-index to follow-up year(s), assessed from 2007 and up to 2017 | 
| Change in asthma disease severity | Change in asthma disease severity assessed by asthma diagnoses, asthma medication use and severe asthma exacerbation | From pre-index to follow-up year(s), assessed from 2007 and up to 2017 |