Prevalence of Allergic Rhinitis and Associated Risk Factors in 6 to 12 Years Schoolchildren From Wuhan in Central China: A Cross-sectional Study

Abstract

Background Over the past decade, the prevalence of allergic rhinitis (AR) in China increased and showed a trend of younger age. The clinical features of AR in primary schoolchildren are still not clear enough. Objective To investigate the prevalence and epidemiological characteristics of AR among 6- to 12-year-old children in the central region of China. Methods Children from 6 primary schools were randomly selected from urban area of Wuhan, which lies in the central region of China. The questionnaires were distributed by mobile APP and filled out by the children and their parents online together. AR was diagnosed by Score for Allergic Rhinitis. Logistic regression analysis was performed to assess the risk factors for AR. Results A total of 5550 valid questionnaires were returned for evaluation. The prevalence of AR among 6- to 12-year-old children in urban area of Wuhan was 28.6%. Multivariate analysis revealed that male (odds ratio [OR] = 1.521, 95% confidence interval [CI] = [1.335, 1.732]), family history of atopy (OR = 3.220, 95% CI = [2.818, 3.681]), previous food allergy (OR = 1.590, 95% CI = [1.302, 1.942]), air purifier (OR = 1.420, 95% CI = [1.240, 1.625]), exposure to dust (OR = 1.764, 95% CI = [1.410, 2.207]), maternal exposure to smoke during pregnancy (OR = 1.242, 95% CI = [1.047, 1.473]), living in towns (OR = 1.468, 95% CI = [1.043, 2.006]) or metropolis (OR = 1.629, 95% CI = [1.205, 2.201]) before 2 years old, frequent application of antibiotics are risk factors for AR, while daily outdoor time for more than 1 hour (OR = 0.770, 95% CI = [0.673, 0.881]) and breastfeeding for more than 6 months (OR = 0.799, 95% CI = [0.701, 0.910]) reduced the risk significantly. Conclusions We found an unexpectedly high prevalence of AR among primary schoolchildren aged 6 to 12 years in the central region of China. Both genetic and environmental factors were associated with the development of AR.

Prolonged breastfeeding and protective effects against the development of allergic rhinitis: a systematic review and meta-analysis

“…Atopic sensitization was investigated by specific IgE tests in nine studies (6,12,27,(29)(30)(31)34,38,46) . Seventeen out of 23 studies had adequate adjustment for confounding variables (6,12,27,28,(30)(31)(32)(33)(34)(35)(36)(40)(41)(42)(43)(44)46) .…”

“…Eighteen studies assessed the effect of prolonged nonexclusive breastfeeding (≥6 months) (6,12,26,28,29,(31)(32)(33)(34)(35)(36)(39)(40)(41)(42)(43)(44)46) . One study (33) used hazard ratio (HR) and found no association with the risk of seasonal AR.…”

“…One hundred and nine studies were selected for full-text review. Twenty-three observational studies (nine cohort studies (6,(26)(27)(28)(29)(30)(31)(32)(33) and 14 crosssectional studies (12,(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46) ) were included for qualitative synthesis, of which 20 studies (12,(26)(27)(28)(30)(31)(32)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46) were included in meta-analysis.…”

“…Nwaru et al (29) used inappropriate cutoff timepoints (five and 9.5 months) of breastfeeding duration in which data were unable to be pooled in the meta-analysis. The pooled data from 15 studies (n=126,708) showed a significant association between nonexclusive breastfeeding for at least six months and its protective effects against the development of AR (OR 0.76; 95% CI 0.69, 0.83; p<0.01) (12,(26)(27)(28)31,(34)(35)(36)(38)(39)(40)(41)(42)(43)46) (Figure 2). The GRADE rating was very low quality due to substantial heterogeneity (I 2 of 69%) and high risk of bias (Table 4).…”

Editorial

“…Although the precise mechanism of this change is not known, it is thought that the C-to-T transition causes an aberrant overexpression of TGFB1, resulting in elevated IgE levels, tissue remodeling and fibrosis. In another Chinese study of school children in the Wuhan province, Tong et al 2 demonstrates a higher prevalence of AR (27%) than previously-reported population data. This study impressively collected cross-sectional data from over 5500 students, revealing several positive risk factors for the development of disease, including male gender, living in an urban setting, and frequent exposure to antibiotics.…”