Childhood obesity and allergic rhinitis: A meta-analysis

Allergic rhinitis (AR) is a prevalent chronic condition in childhood, and its increasing incidence has prompted research into potential associations with modifiable factors such as obesity. This meta-analysis aimed to assess the multivariate-adjusted relationship between childhood obesity and AR. A systematic search was conducted across PubMed, Embase, and Web of Science for observational studies that reported on the association between obesity and AR in children. Only studies that included multivariate adjustments for at least age and sex were considered. Random-effects models were employed to pool odds ratios (ORs) with 95% confidence intervals (CIs), accounting for heterogeneity. Fifteen cross-sectional studies comprising 23 datasets involving a total of 569,856 children were included in the analysis. The overall results indicated that obesity was not significantly associated with AR (adjusted OR: 1.04, 95% CI: 1.00-1.09; p = 0.08; I² = 24%). However, subgroup analyses revealed a significant association in Western countries (OR: 1.12, 95% CI: 1.00-1.24; p = 0.04; I² = 0%), while no significant association was found in Asian countries (OR: 1.04, 95% CI: 0.97-1.12; p = 0.27; I² = 52%). Notable associations were identified in studies utilizing national or international BMI cutoffs (OR: 1.06, 95% CI: 1.01-1.10; p = 0.02) and those with physician-diagnosed AR (OR: 1.07, 95% CI: 1.02-1.13; p = 0.006), but not in studies employing the 95th percentile BMI definition or ISAAC-based AR diagnosis. No significant differences were observed based on age or sex. Meta-regression analysis indicated that age, sex, and study quality score did not significantly influence the results (p all > 0.05). Egger's test revealed no evidence of publication bias (p = 0.43). In conclusion, while no significant overall association between childhood obesity and AR was found, subgroup analyses suggest potential links within specific populations and under particular methodological definitions. These findings should be interpreted with caution, and further longitudinal studies are necessary to determine whether preventive strategies aimed at reducing childhood obesity may also impact allergic outcomes.