title: Association between environmental factors and hospital visits among allergic patients: A retrospective study.
abstract: OBJECTIVE
  This study investigated correlations between meteorological and environmental factors (MEFs) and allergic rhinitis in childhood (ARC).
  
  
  METHODS
  Children who received treatment for AR and meteorological data that might have influenced AR in the same time period were included in this study. Daily average maximum values of sulfur dioxide (SO2), nitrogen dioxide (NO2), and particulate matter (PM10) at 3 a.m. and 8 a.m. were provided by the Shanghai Environmental Bureau for statistical analysis using a generalized additive model (GAM).
  
  
  RESULTS
  Outpatient visits for ARC were higher, with a bimodal shape, for daily average temperatures of about 11 ° C and 21 ° C. However, increasing humidity was associated with a downward trend in outpatient visits for ARC, suggesting that high humidity had a protective effect on AR. When levels of air pollutants such as O3, SO2, and PM10 increased by 10 μg/m3, AR outpatient visits increased by 1.95%, 1.19% and 0.33%, respectively, suggesting that air pollution might increase the risk of AR episodes.
  
  
  CONCLUSIONS
  MEFs were significantly correlated with the incidence of ARC.
authors.affiliation: Department of Ears, Nose, and Throat (ENT), Shanghai Children Medical Center Affiliated of Shanghai Jiaotong University Medical College, Shanghai 200127, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Li
authors.initials: L
authors.lastname: Peng
authors.forename: Shan
authors.initials: S
authors.lastname: He
authors.forename: Youjin
authors.initials: Y
authors.lastname: Li
authors.forename: Zhe
authors.initials: Z
authors.lastname: Mu
mesh_terms: D000293:Adolescent; D000397:Air Pollution / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D006813:Humidity; D015994:Incidence; D008297:Male; D009585:Nitrogen Dioxide / Q000032:analysis; D052638:Particulate Matter / Q000032:analysis; D012189:Retrospective Studies; D065631:Rhinitis, Allergic / Q000453:epidemiology* / Q000209:etiology; D013458:Sulfur Dioxide / Q000032:analysis
chemical_list: D052638:Particulate Matter; D013458:Sulfur Dioxide; D009585:Nitrogen Dioxide