Asthma in changing environments--chances and challenges of international research collaborations between South America and Europe--study protocol and description of the data acquisition of a case-control-study.
BACKGROUND
Asthma in children is an emerging public health problem in South America. So far, research in this part of the world is limited. This paper presents the methodology and description of the data acquisition of an asthma case-control study conducted in the Central South of Chile.


METHODS
A hospital-based case-control study about asthma (188 cases, 294 controls) in children (6-15 years) was carried out in Valdivia, Chile between November 2008 and December 2009. Data on asthma risk factors were collected by computer-assisted personal interview using validated questions from e.g. ISAAC phase II. Data on household dust exposure (endotoxin, allergen analyses), skin prick tests to most common allergens, stool examinations for parasitic infection, and blood samples (total IgE, genetics) were collected. Additionally, 492 randomly chosen blood donors were recruited in order to assess allele frequencies in the population of Valdivia.


CONCLUSIONS
Overall 1,173 participants were contacted. Response was 82% among cases and 65% among controls. Atopic sensitization was high (78% among cases, 47% among controls). Cases had a statistically significantly (p < .0001) increased self-reported 12-month prevalence of symptoms of rhinitis (82% vs. 51%) and wheeze (68% vs. 16%). The study is well placed to address current hypotheses about asthma and its correlates in the South American context. Results of this study might help develop novel, innovative and individualized prevention strategies in countries in transition with respect to the South American context.
Boneberger
Anja
A
Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Hospital of the Ludwig-Maximilians-University Munich, Ziemssenstrasse 1, 80336 Munich, Germany.
Radon
Katja
K
Baer
Jennifer
J
Kausel
Leonie
L
Kabesch
Michael
M
Haider
Daniel
D
Schierl
Rudolf
R
von Kries
Rüdiger
R
Calvo
Mario
M
D000293:Adolescent; D000328:Adult; D000485:Allergens; D001249:Asthma / Q000453:epidemiology* / Q000235:genetics / Q000276:immunology; D001782:Blood Donors / Q000706:statistics & numerical data*; D016022:Case-Control Studies; D002648:Child; D002677:Chile / Q000453:epidemiology; D004391:Dust; D004731:Endotoxins; D004777:Environment; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D005787:Gene Frequency; D014644:Genetic Variation; D006239:Haplotypes; D006801:Humans; D006967:Hypersensitivity / Q000453:epidemiology* / Q000276:immunology; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D008875:Middle Aged; D012220:Rhinitis / Q000453:epidemiology / Q000276:immunology; D012307:Risk Factors; D012882:Skin Tests; D011795:Surveys and Questionnaires; D055815:Young Adult
D000485:Allergens; D004391:Dust; D004731:Endotoxins; D007073:Immunoglobulin E