PIPO project

2 February 2011

UA meets ULg

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Overview

• Epidemiology of asthma and allergies• Cross-sectional vs. longitudinal research• The PIPO birth cohort• The PIPO staff

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Overview

• Epidemiology of asthma and allergies• Cross-sectional vs. longitudinal research• The PIPO birth cohort• The PIPO staff

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Epidemiology of asthma and allergies

• ≥300 million (4.3%) people worldwide • 2 large international epidemiological studies:

- ECRHS in adults- ISAAC in schoolchildren

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ISAAC• International Study on Asthma and Allergies in Children

• School children: 6-7 years and 13-14 years

• Assessment of prevalence of symptoms of asthma, atopic eczema and rhinoconjunctivitis

• Phases:

• Phase 1 (1994-1995): 156 centres in 56 countries

• Phase 2 (1998): 30 centres in 22 countries

• Phase 3 (2002-2003): 237 centres in 98 countries

• Cross-sectional data

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ECRHS

• European Community Respiratory Health Survey• Adults: aged 20-44 years• Assessment of asthma, asthma-like symptoms, atopic

sensitization, bronchial hyper responsiveness• Stages:

- ECRHS 1 (1991-1992) :56 centres in 25 countries - ECRHS 2 (1998): 29 centres in 14 countries- ECRHS 3 (2010-?)

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Results of ISAAC and ECRHS

1. Both studies showed a particularly high prevalence of reported asthma and allergy symptoms in English-speaking countries (i.e. Australia, New Zealand, the UK, the USA and Canada)

2. Both studies showed high asthma and allergy prevalence in Western Europe, with lower prevalences in Eastern and Southern Europe

3. The ISAAC showed that centres in Latin America also had particularly high symptom prevalence

4. The rest of the world outside of the Americas and Western Europe generally showed relatively low asthma prevalence, in particular in developing countries

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Is the prevalence of asthma and allergies still increasing?

• Recent reports of a decline in prevalence of allergies• Review of 48 high quality reports by Anandan et al.

Allergy 2010: 65: 152-167

• Conclusions: - the isolated reports of a decline in asthma prevalence appear to

reflect improvements in the quality of care - the asthma prevalence is continuing to increase or remaining

stable in most parts of the world.

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Overview

• Epidemiology of asthma and allergies• Cross-sectional vs. longitudinal research• The PIPO birth cohort• The PIPO staff

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Cross-sectional vs. longitudinal research

Cross-sectional Longitudinal birth cohort

Quick Time consuming

Retrospective data collection Prospective data collection

Prevalence studies Etiognostic studies

Case-control studies Nested case-control studies

Large chance of recall bias Small chance of recall bias

Difficulty to document antecedents of outcome

Accurate assessment of timing of exposures and outcomes

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Overview

• Epidemiology of asthma and allergies• Cross-sectional vs. longitudinal research• The PIPO birth cohort• The PIPO staff

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The PIPO birth cohort• Prospective birth cohort on the Influence of

Perinatal factors on the Occurrence of Asthma and Allergies (PIPO)

• Recruitment: - 1997-2001- ± 5 months of pregnancy- Gynaecologists- Province of Antwerp, Belgium

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The PIPO birth cohort: Aims

• To study associations between early life factors and health outcomes

• To study the natural course of respiratory and allergy symptoms

• To study immunological profiles

• To study evolution in lung function

Perspective: To study associations between asthma and allergy phenotypes and

genotypes and gene-environment interactions

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Flowchart up to 1 year

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Flowchart 1,5 to 4 years

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Flowchart up to 8 years

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Content of the questionnaires

• Screening Questionnaire: History of asthma and allergies of mother. Father and mother questionnaire: asthma and allergy history of father and mother

• First home visit: - Family composition - Family history (respiratory, eye and nasal symptoms,

hay fever, skin, food allergy) - Maternal smoking - Bedroom+ mattress mother

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Content of the questionnaires

• Second home visit: - Delivery (type, complications, length, weight, head circumference,

Apgar)- Nutrition of the child (breastfeeding, bottle feeding, solids) - Diseases of children (vaccination, skin, respiratory, nasal and eye

symptoms, gastrointestinal symptoms, drugs, smoke exposure) - Pets - House (age of the building, heating, stove, insulation) - Pregnancy (active and passive maternal smoking, diet, diseases,

medications, vitamins and minerals, animals) - Outside (traffic and industry) - Washing habits at 3 months - Data from father and mother (professional, work-related complaints) - Day care (furnishing, heating, animals)

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Content of the questionnaires

• 6 months: - Nutrition (breastfeeding, bottle feeding) - Vaccination - Interior of the house (the child's bed, mattress) - Child care (facility, traffic, heating) - Smoke exposure - Pets

• 12 months telephonic anamnesis: - Fever (reason, medication) - Respiratory symptoms (upper and lower respiratory medication) - Skin symptoms + treatment - Gastrointestinal symptoms- Weight curve

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Content of the questionnaires• 12 months environmental factors

- Food - Other severe familial disorders - Interior of the house - Vaccination - Pets - Smoke exposure - Childcare - Washing habits - Education of parents

• 12 months food frequency questionnaire - Breastfeeding - Bottle feeding - Introduction of solid food

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Content of the questionnaires

• 18, 24, 30, 36, 42 months questionnaire - Food - Interior of the house - Vaccinations - Pets - Smoke exposure - Childcare - Washing habits - Diseases of the child (skin, respiratory, nasal and eye complaints, hay

fever, fever, otitis media, gastrointestinal symptoms, medication)

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Content of the questionnaires• 4, 5, 6, 7, 8 years questionnaire

- Family composition - Food - Interior of the house - Pets - Smoke exposure - Childcare - Diseases of the Child (skin, respiratory, nasal and eye complaints,

hay fever, fever, medication otitis media, other diseases, homeopathy)

- Sleep and behaviour of the child (sleep patterns, polyps, tonsils, behavioural problems, bedwetting, teeth)

- Physical activity - Traffic

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Lung function tests

• At 4 years of age: - Forced oscillation technique (FOT) + reversibility

• At 8-10 years of age: - FOT + reversibility- Spirometry + reversibility- Exhaled nitric oxide (eNO)

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Blood samples: Immunology

Total IgE serum specific IgE

• Parents:

- D. pteronyssinus, cat, dog, birch pollen, grass pollen, mugwort pollen and Cladosporium herbarum

• Child:

- 1 year: D. pteronyssinus, cat, dog, hen’s egg, cow’s milk

- 4 & 8 years: D. pteronyssinus, cat, dog, hen’s egg, cow’s milk, grass pollen, birch pollen

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Blood samples: Genetics

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Strengths of PIPO

• Inclusion before the end of pregnancy information on prenatal exposures

• Longitudinal follow-up: prenatal to pre-puberty temporal relationships between early-life factors and development of asthma and allergies

• Data collection: questionnaires + objective measurements

• Blood samples for genetic analyses• Multidisciplinary approach

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Overview

• Epidemiology of asthma and allergies• Cross-sectional vs. longitudinal research• The PIPO birth cohort• The PIPO staff

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PIPO staff: supervisors

• Supervisor: Joost Weyler, MD, PhD (Epidemiology and Social Medicine)

• Co-supervisor: Ellie Oostveen, MSc, PhD (Respiratory Medicine)

• Co-supervisor: Margo Hagendorens, MD, PhD (Pediatrics and Immunology)

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PIPO staff: scientific personnel

• ESOC:- Jos Droste, MD- Sandra Dom, MSc

• Immunology: Chris Bridts, MSc• Pediatrics: Elke Dierckx, MD

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PIPO staff: ATP

• Administrative management: Chris Daenen (ESOC)

• Lab technician: Christel Mertens (Immunology)• Lung function technician: Ria Heyndrickx

(Respiratory Medicine)