Environmental risk factors for allergic rhinitis differ by income level: A Global Asthma Network survey.

BACKGROUND

Estimating the prevalence and identifying risk factors for allergic rhinitis (AR) provides critical burden of disease data and offers opportunity to intervene in early-life preventing morbidity.

METHODS

We conducted a Global Asthma Network (GAN) Phase I cross-sectional study in children (6-7 years) and adolescents (13-14 years). Multilevel logistic regression models were fitted with random intercepts for school, center, and country, adjusting for sex and country income at the child level. Associations between symptoms and a range of lifestyle and environmental risk factors were assessed using odds ratios and corresponding 95% confidence intervals for mean individual and school exposure. Participants provided informed consent/assent, and each center was required to provide proof of ethical clearance.

RESULTS

We analysed data from 266,182 children and adolescents across 1688 schools in 65 centers for AR symptoms. Prevalence was 8.5% in children and 13.3% in adolescents. Early-life exposures strongly associated with AR included paracetamol use (OR: 2.03; 95% CI: 1.89-2.18) and antibiotics (OR: 1.67; 95% CI: 1.56-1.78), with a stronger effect for antibiotics in low- and middle-income countries (LMICs). Farm animal exposure increased AR risk among LMIC children (OR: 1.31; 95% CI: 1.12-1.53). In adolescents, computer use (OR: 1.28; 95% CI: 1.22-1.35) and tobacco use (OR: 1.37; 95% CI: 1.29-1.46) were significant risk factors. Heavy truck traffic consistently elevated AR risk in both age groups.

CONCLUSION

The prevalence of AR is stable; early-life exposures to animals increased the risk for AR in children from LMICs. Lifestyle factors and poor air quality from traffic-related pollutants increase the risk of AR.