Childhood eczema and asthma incidence and persistence: a cohort study from childhood to middle age.
BACKGROUND
The association between eczema and asthma is well documented, but the temporal sequence of this association has not been closely examined.


OBJECTIVE
To examine the association between childhood eczema and asthma incidence from preadolescence to middle age, and between childhood eczema and asthma persisting to middle age. A further aim was to examine any effect modification by nonallergic childhood exposures on the association between childhood eczema and both childhood asthma and later life incident asthma.


METHODS
Data were gathered from the 1968, 1974, and 2004 surveys of the Tasmanian Longitudinal Health Study. Multivariable logistic regression examined the association between childhood eczema and childhood asthma. Cox regression examined the association between childhood eczema and asthma incidence in preadolescence, adolescence, and adult life. Binomial regression examined the association between childhood eczema and childhood asthma persisting to age 44 years.


RESULTS
Childhood eczema was significantly associated with childhood asthma and with incident asthma in preadolescence (hazard ratio [HR], 1.70; 95% CI, 1.05-2.75), adolescence (HR, 2.14; 95% CI, 1.33-3.46), and adult life (HR, 1.63; 95% CI, 1.28-2.09). Although childhood eczema was significantly associated with asthma persisting from childhood to middle age (relative risk, 1.54; 95% CI, 1.17-2.04), this association was no longer evident when adjusted for allergic rhinitis.


CONCLUSIONS
Childhood eczema increased the likelihood of childhood asthma, of new-onset asthma in later life and of asthma persisting into middle age.
Burgess
John A
JA
Centre for Molecular, Environmental, Genetic and Analytic Epidemiology, University of Melbourne, Carlton, Australia. j.burgess@pgrad.unimelb.edu.au
Dharmage
Shyamali C
SC
Byrnes
Graham B
GB
Matheson
Melanie C
MC
Gurrin
Lyle C
LC
Wharton
Cathryn L
CL
Johns
David P
DP
Abramson
Michael J
MJ
Hopper
John L
JL
Walters
E Haydn
EH
D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000453:epidemiology* / Q000276:immunology; D002648:Child; D015331:Cohort Studies; D004485:Eczema / Q000453:epidemiology* / Q000276:immunology; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D016016:Proportional Hazards Models; D013648:Tasmania / Q000453:epidemiology