Canadian Asthma Primary Prevention Study (CAPPS)

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Canadian Asthma Primary Prevention Study (CAPPS)
Chris Carlsten, MD MPH University of British
Columbia
Chris Carlsten University of British
Columbia Genesis of Asthma and Allergy Workshop,
Mar-1-09
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Initiating PIs (early 1990s)
Allan Becker Moira Chan-Yeung Funding
CIHR BC Lung Association Manitoba Medical
Service Fund

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Establishment of cohort

• mothers of high-risk infants (n 545) from
  Vancouver and Winnipeg were recruited during the
  third trimester of pregnancy
• high-risk was defined as having at least one
  first-degree relative with asthma or two
  first-degree relatives with IgE-mediated allergic
  disease
• families were randomized to the control (usual
  care) or intervention group
• avoidance of HDM, pet allergen, and ETS
• breast-feeding encouraged
• formula supplementation if necessary
• introduction of solid foods delayed

Chris Carlsten, MD MPH University of British
Columbia
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Establishment of cohort

Chris Carlsten, MD MPH University of British
Columbia
Chan-Yeung Arch Ped 2000
Note 380 (70) returned for assessment at 7
years of age
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Establishment of cohort

Chris Carlsten, MD MPH University of British
Columbia
Chan-Yeung Arch Ped 2000
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Exposures and related analytes(http//genapha.ica
pture.ubc.ca)

Chris Carlsten, MD MPH University of British
Columbia
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Outcomes

• A pediatric allergist-based diagnosis of asthma
  and rhinitis
• Questionnaire-based symptoms and medication use
• IgE in blood
• Atopy (skin prick positive to 1 of 13 antigen
  panel)
• URI (by report)
• Methacholine challenge PC20
• Another attractive discussion point PC202
  best AUC for sensitivity and specificity relative
  to MD diagnosis preliminary data from Helen
  Ward, PhD

Chris Carlsten, MD MPH University of British
Columbia
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Strengths

• high-risk cohort (enhanced for outcomes of
  interest)
• detailed phenotyping (including PC20)
• detailed early life exposure (including cord
  blood)
• LUR
• 7 year follow-up, with recent new funding for 14
  years

Chris Carlsten, MD MPH University of British
Columbia
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Weaknesses

• High risk design limits generalizability
• Randomized intervention within study complicates
  the analysis of gene-environment interactions
• Modest N
• a great topic for discussion in this meeting

Chris Carlsten, MD MPH University of British
Columbia
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Selected publications
Becker A, Manfreda J, Chan-Yeung M.
Environmental tobacco smoke exposure and breast
feeding. Archives Pediatr Adoles Med
1999153689-691 Chan-Yeung M, Becker A.
Umbilical cord blood mononuclear cell
proliferative response does not predict the
development rhinitis and asthma. JACI
99 Kaan A, Chan-Yeung M. Cord blood IgE
development of asthma and other allergic
disorders at 12 months. Ann Allergy, Asthma and
Immunol 20008437-42. Zhu S, Sandford A.
Polymorphisms of IL-4, TNF-alpha, and FceRIb
genes and the risk of allergic disorders in
at-risk infants. AJRCCM 20001611658-9. Chan-Ye
ung M, Becker A. A randomized clinical trial
the primary prevention of asthma in high risk
infants. Arch Pediatr Adolescent Med 2000 154
657-663. Hegele RG, Chan-Yeung M. The
association between respiratory viruses and
symptoms in 2-week-old infants ... J Pediatrics
2001 138 831-7. Chan-Yeung M, Becker A.
Effectiveness in reducing allergen levels in a
primary prevention of asthma study. Annals of
AAI 2002 8852-58. He J-Q, Sandford AJ.
Genetic variants of the IL13 and IL4 genes and
atopic diseases in at-risk children. Genes and
Immunity (2003) 4, 385389 Becker A,
Chan-Yeung M. The Canadian Primary Prevention of
Asthma study- outcomes at 2 years of age. J
Allergy Clin Immunol 2004 113650-656. Chan-Yeun
g M, Becker A. The Canadian Primary Prevention
of Asthma in Childhood- outcomes at 7 years. JACI
2005 116 49-55 Chan-Yeung M, Becker A.
Primary prevention of asthma and allergies in
childhood. Cur Opinion Allergy Clin Immunol
20066146-51 Lee KK, Chan-Yeung M. Exposure
to respiratory viruses and onset of asthma and
atopy outcome at 2 years of age. Pediatrics
Pulmonol 2007 42290-7 Begin P, Laprise C.
Association of urokinase-type plasminogen
activator with asthma and atopy. Am J Respir
Crit Care Med 20071751109-16 Chan-Yeung M,
Becker A. Early life factors for bronchial
hyperrepsonsiveness at age 7 in a high risk
cohort. Am J Respir Crit Care Med 2007175 A270
Chan-Yeung M, Becker A. Atopy in early life
and impact of a primary prevention program for
asthma in a high risk cohort. J Allergy Clin
Immunol 2007 Ferguson A, Chan-Yeung M. Elevated
cord blood IgE is associated with recurrent
wheeze and atopy at 7 years in a high risk
cohort. PAI 2009
Chris Carlsten, MD MPH University of British
Columbia