Role of environmental exposures and filaggrin mutations on associations of ethnic origin with risk of childhood eczema. The Generation R Study.
The prevalence of childhood eczema varies considerably between ethnic groups. However, data from longitudinal studies remain scarce.



We examined the associations of ethnic origin with the development of eczema from birth until the age of 4 years, and whether known environmental and genetic risk factors explain these associations. This study was performed in a multiethnic population-based prospective cohort among 5,082 children. Ethnic origin was based on the parents' country of birth. Data on physician-diagnosed eczema were obtained by annual questionnaires. Information on environmental risk factors was mostly obtained by questionnaires. Filaggrin (FLG) mutations (2282del4, R2447X, R501X, and S3247X) were genotyped for 3,096 children. We used generalized estimating equation models to examine the associations of ethnic origin with the longitudinal odds of eczema at 6 months and 1, 2, 3, and 4 years of age overall and independently.



Compared with Dutch children, Cape Verdean, Dutch Antillean, Surinamese-Creole, and Surinamese-Hindustani children had overall increased risks of eczema (OR (95%-CI): 1.53 (1.15, 2.03), 1.60 (1.21, 2.12), 1.95 (1.56, 2.44), and 2.06 (1.65, 2.57), respectively). Effect estimates for the associations of Cape Verdean and Dutch Antillean origin with eczema became non-significant after adjustment for genetic risk factors or both environmental and genetic risk factors, respectively. Surinamese-Creole and Surinamese-Hindustani children remained to have increased risks of eczema.



Cape Verdean, Dutch Antillean, Surinamese-Creole, and Surinamese-Hindustani children had increased risks of eczema in the first 4 years of life. Environmental and genetic risk factors partly weakened these associations.
The Generation R Study Group, Erasmus Medical Center, Rotterdam, The Netherlands.|Department of Dermatology, Erasmus Medical Center, Rotterdam, The Netherlands.
Niels J
NJ
Elbert
Division of Respiratory Medicine, Department of Pediatrics, Erasmus Medical Center, Rotterdam, The Netherlands.|Division of Neonatology, Department of Pediatrics, Erasmus Medical Center, Rotterdam, The Netherlands.|Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.
Liesbeth
L
Duijts
The Generation R Study Group, Erasmus Medical Center, Rotterdam, The Netherlands.|Division of Respiratory Medicine, Department of Pediatrics, Erasmus Medical Center, Rotterdam, The Netherlands.|Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.
Herman T
HT
den Dekker
The Generation R Study Group, Erasmus Medical Center, Rotterdam, The Netherlands.|Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.|Department of Pediatrics, Erasmus Medical Center, Rotterdam, The Netherlands.
Vincent W V
VW
Jaddoe
The Generation R Study Group, Erasmus Medical Center, Rotterdam, The Netherlands.|Division of Respiratory Medicine, Department of Pediatrics, Erasmus Medical Center, Rotterdam, The Netherlands.|Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.
Agnes M M
AM
Sonnenschein-van der Voort
Division of Respiratory Medicine, Department of Pediatrics, Erasmus Medical Center, Rotterdam, The Netherlands.
Johan C
JC
de Jongste
Department of Dermatology, Erasmus Medical Center, Rotterdam, The Netherlands.
Suzanne G M A
SG
Pasmans
D002675:Child, Preschool; D015331:Cohort Studies; D004485:Eczema / Q000453:epidemiology* / Q000235:genetics; D004781:Environmental Exposure / Q000009:adverse effects; D005006:Ethnicity; D005260:Female; D000091344:Filaggrin Proteins; D005500:Follow-Up Studies; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007381:Intermediate Filament Proteins / Q000235:genetics*; D008297:Male; D009154:Mutation / Q000235:genetics*; D009426:Netherlands / Q000453:epidemiology; D015995:Prevalence; D011446:Prospective Studies; D012306:Risk
C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins
birth cohort; children; eczema; ethnic origin; filaggrin