Impact of Age on the Prevalence of Allergic Sensitization

Study Overview
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Brief Summary
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Worldwide, respiratory diseases have a significant impact on morbidity and mortality of individuals.Tobacco, lifestyle and certain allergens such as dust mites play an important role in the prevalence and morbidity of these diseases. Scientific literature indicates that sensitization to allergens and respiratory diseases (asthma, rhinitis, chronic obstructive pulmonary disease) are closely linked. Moreover, smoking has an effect on allergen sensitivity. To make a diagnosis of allergic sensitization, skin tests are performed in the patient. One of the methods used is the technique of prick test. In practice, a drop of purified allergen extract is placed on the patient's skin (arms or back). A little dosis of the product is then injected in the epidermis. If fifteen minutes later, there is an edematous reaction, its diameter is measured in millimeters. From 4 mm, it is considered that the patient is sensitized to the tested foods or allergens.This technique is painless and convenient to patients of all ages, including newborns or conversely very aged patients. This is a retrospective study based on the encoding and statistical analysis of data collected in patients followed within the Immuno-Allergology Service of the CHU Brugmann Hospital, who received an allergy assessment between 01/01/2015 and 31/12/2015. The allergens tested include: dermatophagoides pteronyssinus (DEPT), dermatophagoides farinae (DPF), blomia, cat, dog, cockroach, orchardgrass, timothy grass, alder, hazel,birch, olive tree, cypress, ash, latex, aspergillus, alternaria, cladosporium, peanut, hazel. At least 1400 files will be analyzed. Patients will be distributed in six age groups.The results of the allergen skin tests will be encoded as the edema diameter. The allergenicity score (mean of the skin reactivities for each allergen) will be compared between each age groups. The impact of tabagism, gender, BMI and residential area on the allergic reactivity will also be assessed in the overall population and within each age group. The main objective is to evaluate the effect of age on the skin test positivity. The secondary objective is to highlight the environmental factors that have an impact on allergic diseases.

Official Title
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Impact of Age on the Prevalence of Allergic Sensitization

Conditions
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Allergy

Intervention / Treatment
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* Other: Retrospective analysis of patient files


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients followed within the Immuno-Allergology Service of the CHU Brugmann Hospital Who received an allergy assessment between 01/01/2015 and 31/12/2015. The allergens tested include: dermatophagoides pteronyssinus (DEPT), dermatophagoides farinae (DPF), blomia, cat, dog, cockroach, orchardgrass, timothy grass, alder, hazel,birch, olive tree, cypress, ash, latex, aspergillus, alternaria, cladosporium, peanut, hazel. Exclusion Criteria: Negative histamine patients

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Immuno-allergology patients<br>Patients followed within the Immuno-Allergology Service of the CHU Brugmann Hospital, who received an allergy assessment between 01/01/2015 and 31/12/2015. At least 1400 dermis will be analyzed. The allergens tested include: dermatophagoides pteronyssinus (DEPT), dermatophagoides farinae (DPF), blomia, cat, dog, cockroach, orchardgrass, timothy grass, alder, hazel,birch, olive tree, cypress, ash, latex, aspergillus, alternaria, cladosporium, peanut, hazel. | Other: Retrospective analysis of patient files<br>* The results of the allergen skin tests will be encoded as the edema diameter. The allergenicity score (mean of the skin reactivities for each allergen) will be compared between each age groups. The impact of tabagism, gender, BMI and residential area on the allergic reactivity will also be assessed in the overall population and within each age group.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Allergenicity score | Mean of the skin reactivities for each allergen. The results of the allergen skin tests are encoded as the edema diameter. Scores will be compared between the different age groups. | one year (01/01/2015 to 31/12/2015) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Smoking status | Effect of the smoking/non smoking status on the allergic reactivity, analysed in the hole group and in the different age groups. | one year (01/01/2015 to 31/12/2015) | 
| Geographic localisation | Effect of the area of residence on the allergic reactivity, analysed in the hole group and in the different age groups. | one year (01/01/2015 to 31/12/2015) | 
| Sex | Gender effect on the allergic reactivity, analysed in the hole group and in the different age groups. | one year (01/01/2015 to 31/12/2015) | 
| Body Mass Index | Effect of the body mass index on the allergic reactivity, analysed in the hole group and in the different age groups. | one year (01/01/2015 to 31/12/2015) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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respiratory disease, allergen sensitization, aging, skin tests, air allergens