Persistence and remission in childhood asthma: a population-based asthma birth cohort study.
OBJECTIVE
To examine and predict the persistence of childhood asthma.


METHODS
Longitudinal population-based cohort study.


METHODS
Ontario, Canada.


METHODS
Children born in 1994 and diagnosed with asthma before age 6 years were followed up until age 11 years. Diagnosis of asthma was defined as 1 asthma hospitalization or 2 asthma physician claims within 3 years prior to age 6 years.


METHODS
Intensity of health services use within 1 year postdiagnosis.


METHODS
Those who continued to have asthma events (hospitalization and/or physician visit) between ages 6 and 11 years were considered to have "persistent asthma," while others were in "remission." Cumulative rates of health services use for asthma during follow-up were calculated. Logistic regression analysis was used to estimate risks of persistent asthma.


RESULTS
The study included 34,216 children diagnosed with asthma before age 6 years. More than half (54.4%) experienced a second asthma health care encounter within 1 year after diagnosis. By age 12 years, nearly half (48.6%) were in remission. Children with asthma hospitalization during the first year postdiagnosis had a 3-fold risk of persistent asthma by age 12 years (95% confidence interval, 2.69-3.39; P < .001). Those with at least 4 physician visits also had a 2.6-fold risk of persistent asthma during follow-up (95% confidence interval, 2.34-2.81; P < .001).


CONCLUSIONS
The concentration of health services use within 1 year following the initial diagnosis of childhood asthma points to the need for attentive follow-up and ongoing management and education strategies in the early years.
To
Teresa
T
Child Health Evaluative Sciences, Research Institute, The Hospital for Sick Children, 555 University Ave, Toronto, ON M5G 1X8, Canada. teresa.to@sickkids.on.ca
Gershon
Andrea
A
Wang
Chengning
C
Dell
Sharon
S
Cicutto
Lisa
L
D000367:Age Factors; D001249:Asthma / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D002669:Child Welfare; D002675:Child, Preschool; D002908:Chronic Disease; D019992:Databases as Topic; D018450:Disease Progression; D005260:Female; D006296:Health Services / Q000706:statistics & numerical data; D006305:Health Status Indicators; D006801:Humans; D008297:Male; D009864:Ontario; D011446:Prospective Studies; D012008:Recurrence; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors