Presentation on theme: "Allergy related symptoms and Infections Questionnaire with ISAAC and hygiene questions. Children aged 6-7 years, in two different schools: 1-a middle class."— Presentation transcript:
Allergy related symptoms and Infections Questionnaire with ISAAC and hygiene questions. Children aged 6-7 years, in two different schools: 1-a middle class school (43 children) 2-a low class school (20 children) Laura Vega (MD Paediatrician) Marcelo Escobar (biologist) Neuquén Argentina
Hygiene Hypothesis: « This theory claims that hygiene removed a protective influence against atopy and asthma that was once provided by exposure to infections in early life. » Matricardi PM, Bouyque GR, Tripodi S. Inner-city asthma and the hygiene hypothesis. Ann Allergy Asthma Immunol 2002 Dec; 89 (6 Suppl 1) : Background
« In children aged 6-7 years the prevalence of asthma ever ranged from 4,1-26,9% and the prevalence of wheezing in the last 12 months from 8,6-26,9%.» « The high figures for asthma in a region with a high level of gastrointestinal parasite infestation, and a high burden of acute respiratory infections occurring early in life, suggest that these factors, considered as protective in other regions, do not have the same effect in this region. The prevalence of asthma and related symptoms in Latin America is as high and variable as described in industrialized or developed regions of the world. » Mallol, J et al. Prevalence of asthma symptoms in Latin America: The International Study of Asthma and Allergies in Childhood (ISAAC).Pediatr.Pulmonol.2000 Dec;30 (6): Background
Objective To study the relationship between hygiene conditions and allergy related symptoms in this region, in order to verify the hygiene hypothesis.Introduction In my personal experience as a paediatrician and allergy specialist, I do not see differences in allergic disease`s frequency between people belonging to different social classes, despite their huge differences in quality of life.
A questionnaire filled by parents, with ISAAC* core questions to which hygiene** questions were added, for school children 6-7 years old. Weight and Height were obtained by the authors in all the children that completed the questionnaire. * Asher MI, Anderson JIR, Beasley R, et al.International Study of Asthma and Allergies in Childhood (ISAAC): rationale and methods. Eur Respir J 1995;8: ** Breast feeding, tobacco smoking, respiratory infections, diarrhea, parasites, hepatitis, vaccinations,hospitalisations, pets at home, lodging conditions, cooking conditions, heating conditions, number of family members, day care attendance, sports. Methods
Climate: -Temperate: mean temperature 15 centigrades (max 40, min –15) -Dry: 56% Humidity,Year Av., Rain 199 mm year Av. -High Winds (gusts until 120 km/hr, mainly in Spring) -230 m above sea level -Soil typical of the desert, with a superficial lay of muds, sands and clays
Neuquén Downtown Bidonville
Middle Class School (43 children) Current wheezing 30% Ever wheezing 51% Current rhinitis 21% Ever rhinitis 27% Atopic dermatitis 16% Low Class School (20 children) Current wheezing 30% Ever wheezing 45% Current rhinitis 30% Ever rhinitis 30% Atopic dermatitis 20% Results:
Middle Class School (43 children) Diarrhea 44% Diarrhea once 16% Diarrhea many times 25% Low Class School (20 children) Diarrhea 55% Diarrhea once 20% Diarrhea many times 25% Diarrhea
There is a positive correlation between infections and allergy related symptoms: Utilizing descriptive statistics (chi-square tests for cross tabs),we found that some variables are not independent, and statistically significants, for a P-Value = 0,05 Parasites and current wheezing (p= 0,002) Parasites and ever wheezing (p= 0,016) Respiratory infections and ever wheezing (p= 0,005) Bronchiolitis and ever wheezing (p= 0,010) Bronchiolitis and current rhinitis (p= 0,013) Diarrhea and current rhinitis (p= 0,022) Giardia Lamblia and ever rhinitis (p= 0,023) Diarrhea and ever rhinitis (p= 0,013) Hepatitis and Atopic dermatitis (p= 0,002)
Univariate logistic regression analysis (SPSS) Factor current rhinitis OR 95% CI Diarrhea 11 4,20 1,16-15,13 Diarrhea 3 6 3,91 1,06-14,43 Factor ever rhinitis OR 95% CI Diarrhea 13 4,28 1,30-14,13 Diarrhea 2 5 5,39 1,13-25,64 Giardia L 5 5,39 1,13-25,64 In a multivariate logistic regression analysis, diarrhea is a risk factor for current rhinitis and ever rhinitis.
Allergy related symptoms frequency (ISAAC questions), is high and similar in both groups of children. Infectious diseases (questionnaire) are frequent in both groups of children. Could it be that diarrhea and other infectious diseases do not have the protective effect for allergy that has been suggested in the hygiene hypothesis? Conclusion
1- continue inviting school children`s parents to answer the questionnaire in different schools from Neuquén City, and other villages in the interior of the province. 2- perform objective tests in allergic individuals detected by the questionnaire, and in non allergic controls : - Skin Prick Tests (with common regional allergens) - Spirometry (basal conditions and after exercise) Future research
Jean Luc Malo Heberto Ghezzo Denyse Gautrin Sylvie Levesque Andrés Finzi Thanks