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Dr Becker from Manitoba speaking on development of atopic conditions & life trajectories. Dr Allan Becker from U of Manitoba on the CHILD study and the determinants of allergic disease.
Hygiene hypothesis and allergy epidemic
.@allanbecker2 points out that the Hygiene Hypothesis was actually first stated by a Canadian Dr John Gerrard in 1976. A reminder that Canadian allergist John Gerrard postulated the hygiene hypothesis in 1976. John Gerrard 1976 postulated this inverse relationship. Give us this day our daily germs (Immunology Today 1998).
UN general assembly described slow motion epidemic in 2011. UN called non-communicable diseases, including allergy, an epidemic unfolding in slow motion.
Almost half of all children wheeze in the pre-school years. About 1/2 of preschool children will have at least one episode of wheezing. The question: which become asthmatic?
Early changes in lung function by age 3
Things get set off in early life. Pulmonary function while in normal range is in the low range and follows this trend. Structural modification is set by age 10. But kids are not born this way, it occurs around 2-3 years of life. Evidence of airway remodeling in recurrent/frequent wheezers already identified by age 3. Airway remodelling in asthmatic children can already be present at the age of 29 months. The more severe and frequent the airway inflammation, the greater the likelihood of structural changes/remodeling. The Dunedin study showed that asthma was present at childhood. Irreversible structural changes might start early. We need to focus on young kids with window of opportunity to prevent the development of allergies & asthma. Airway remodeling can occur in toddler years, adding more evidence to treat persistent asthma/wheezing.
Canadian Asthma Primary Prevention Study (CAPPS)
CAPPS stands for Canadian Asthma Primary Prevention Study headed by Dr Becker - multidimensional interventional study. Small but significant changes in lung function in young children with asthma dx (age 7) compared to controls in CAPPS study.
Skin test positive status highly associated with asthma: Atopy at 1 yr is the most significant risk factor asthma at age 7 yr
Marked increase in risk for persistent wheeze in teens if positive SPT by age 2. Skin test positive much more likely to develop persistent wheezing. Early life atopy a strong predictor of asthma. Skin test positive status highly associated with asthma at 7 yo in @allanbecker2's study.
Dr. Becker: If you are allergic (skin test positive) in first 2y of life, there is an increased risk for persistent asthma by teen yrs.
Risk factors for asthma at 7 years: Male child, Mother with asthma, Father/sibling with asthma, Atopy at 1 year RSV. Atopy (positive SPT) at age is a bigger risk for persistent asthma than maternal history, RSV, other risk factors, in CAPPS study. Atopy at 1 yr is the most significant risk factor asthma at age 7 yr. Atopy the age of 1 seems to be a huge determinant of likelihood of asthma at age 7. Timing of atopy, even if it disappears, is a risk for developing asthma.
Factors critical to development of asthma: genes, environment AND atopy in early life (in particular food allergy). Factors critical to development of asthma: genes, environment AND atopy in early life (in particular). Genetics play a big role in allergy and asthma, “choose your parents wisely.”
PFT changes worse at 15 years with all wheezy phenotypes: transient wheeze less than late onset less than persistent wheeze.
Canadian healthy infant longitudinal development study @CHILDSTUDY
Child study looked at enviro factors. @CHILDSTUDY came about to fully study the determinants of asthma/atopy in Canadian children.
The @CHILDSTUDY, perhaps luckily, studied the role of gut microbiota. A lot of the articles on this from @MeghanAzad.
It's cool that scientific studies have Twitter handles now, example @CHILDSTUDY - investigators worldwide take note, find a good Twitter handle.
Reminder about CTS/CPS position paper: Diagnosis and management of asthma in preschoolers: https://t.co/vZUJ9jiT4S