Wheezing phenotypes in young children: an historical cohort study

Abstract

Background: Wheezing phenotypes in young children have usually been described on the basis of questionnaire surveys instead of prospectively doctor-diagnosed episodes, and have never been described in terms of incidence rates. Aims: To identify wheezing phenotypes in the first three years and describe their incidence trends, and to investigate their relationship with asthma at six years of age. Methods: Doctor-diagnosed wheezing episodes in the first 36 months and active asthma at six years were identified in a historical cohort of 3,739 children followed from birth in 29 primary care health centres in Spain. Wheezing phenotypes were identified by means of latent class analysis. Changes in incidence rates of wheezing were identified through joinpoint regression models and their predictive ability for asthma was analysed. Results: One never/infrequent wheeze phenotype and three wheezing phenotypes were identified. There were two early phenotypes which started wheezing at a median age of six months, one of which was transient while the other had a heavy recurrence of episodes. A third phenotype exhibited a delayed onset of wheezing, a constant rise in incidence through the first 36 months, and a relationship with allergic asthma. These three phenotypes had a higher prevalence of active asthma at six years than the never/infrequent wheeze phenotype, but the classification had a weak predictive ability for asthma due to low sensitivity. Conclusions: The use of incidence rates contributes to the clarification of the natural history of infant wheezing.

Maternal and cord blood vitamin D status and childhood infection and allergic disease: a systematic review

“…The prevalence of childhood wheezing is much higher than that of asthma, and it is difficult to know which "wheezers" have predilection for asthma. 70,71 Given the strong link between childhood wheezing and viral respiratory tract infection (due to smaller airway caliber and inflammation), wheezing could also act as a marker for increased risk of infection or for higher symptom severity when infected. 72 Four studies looked at both of these outcomes: Camargo et al 32 found a negative association (similar in size as well) between cord blood 25(OH)D and both wheeze and respiratory infection.…”

Factors associated with the time to the first wheezing episode in infants: a cross-sectional study from the International Study of Wheezing in Infants (EISL)

“…Wheezing during the first months of life might be associated with later asthma, especially when episodes are severe and/or frequent. 14 , 16 , 17 Time to the first episode of wheeze has been associated with the frequency of recurrence: the earlier the first episode occurs, the more frequently wheezing recurs. 18 It is possible that some environmental factors could influence the innate immune response during the first months of life, a critical period for immune system development, resulting in more frequent and severe episodes of wheezing.…”

Criteria heterogeneity in the diagnosis of acute bronchiolitis in Spain

“…29---31 Among the scarce evidence that may contribute to resolve this issue, we ought to highlight a Spanish community-based study of incident cases that identified a specific wheezing pattern consisting of a single episode typically occurring before age 13 months, with the incidence peak at 7 months. 32 On the other hand, both experts and clinical paediatricians agreed that AB is a term that should only be applied to a first episode. McConnochie 20 was the first to include this criterion in his definition of AB in 1983.…”