Reduced prevalence of rhinitis and eczema but not wheezing in native-born children from cross-border marriages.

BACKGROUND: Gene-environment interactions may lead to varying predispositions to different allergies. Children from cross-border marriage families were predominantly born in Taiwan. This study aimed to compare allergic disease prevalence in children from families with foreign female spouses to those with Taiwanese female spouses and assess the association between female spouse origin and allergic diseases. METHODS: This population-based, cross-sectional survey on 3172 grade-one schoolchildren aged 6-8 in Taiwan used stratified cluster random sampling. We used logistic regression to examine the association between covariates (including demographics, female spouse origin, perinatal and other exposures) and outcomes (wheezing, allergic rhinitis/hay fever ever, and eczema). RESULTS: Among 3172 children, 13.8% had at least one foreign-born parent, predominantly female spouses (11.7%), with 2.6% being foreign-born male spouses. In families with foreign-born female spouses, children (95.5% born in Taiwan) showed a lower prevalence of allergic diseases than those from Taiwan, including ever having rhinitis [29.4% vs. 51.0% (P-value < 0.001) in boys and 31.4% vs. 42.5% (P-value: 0.009) in girls], current rhinitis [25.6% vs. 46.9% (P-value < 0.001) in boys and 28.1% vs. 38.4% (P-value: 0.013) in girls], ever diagnosed with allergic rhinitis/hay fever [24.9% vs. 34.7% (P-value: 0.034) in boys and 17.0% vs. 29.2% (P-value < 0.001) in girls], and diagnosed eczema [15.3% vs. 27.6% (P-value: 0.001) in boys and 11.2% vs. 22.2% (P-value: <0.001) in girls]. Adjusted for covariates, boys from families with a foreign female spouse had lower odds of ever having rhinitis (adjusted odds ratio = 0.498, 95% confidence interval: 0.322-0.772), current rhinitis (aOR = 0.480, 95% CI: 0.310-0.743) and diagnosed eczema (aOR = 0.472, 95% CI: 0.273-0.815). Similarly, girls from these families had lower odds of ever being diagnosed with allergic rhinitis/hay fever (aOR = 0.591, 95% CI: 0.351-0.994) and diagnosed with eczema (aOR = 0.536, 95% CI: 0.303-0.947). CONCLUSION: Cross-border marriage children had lower odds of developing rhinitis and eczema than those from native families, highlighting the importance of genetics or interactions between genetic and environmental influences on allergies. Additionally, gene-environment interactions exhibited varying impacts on childhood allergies.