title: Adult asthma exacerbations and environmental triggers: a retrospective review of ED visits using an electronic medical record.
abstract: BACKGROUND
  Despite familiarity with triggers for asthma, there is little recent study on the association of triggers with the emergency department (ED) presentation of adult asthma exacerbation.
  
  
  METHODS
  Retrospective electronic chart review of adult patients treated in an urban teaching hospital ED with chief complaint and diagnostic coding related to asthma and upper respiratory tract infection (URI) was conducted. Monthly aeroallergen data and environmental conditions were obtained from a local allergen extract laboratory and local government sources. Data analysis was performed using Newey-West time series regression modeling with adjustment for autocorrelation or ordinary least squares linear regression modeling using outcome variables of asthma visits and admissions.
  
  
  RESULTS
  There were 56, 747 visits, with 554 asthma visits and 1,514 URI visits. Asthma visits (R(2) = 0.631) were positively correlated with tree pollen counts (correlation coefficient = 0.458 [0.152-0.765]) and average humidity (correlation coefficient = 1.528 [0.296-2.760]). Asthma admissions (R(2) = 0.480) were negatively correlated with average temperature (correlation coefficient = -0.557 [-1.052 to -0.061]) when adjusting for confounding by fine particulate matter.
  
  
  CONCLUSIONS
  The ED acute asthma exacerbation presentation is positively correlated with tree pollen and humidity, whereas need for admission is associated with dropping temperatures. These results reinforce the need for vigilance during periods of increased risk and perhaps focused preventative strategies.
authors: Department of Emergency Medicine, The George Washington University, Washington, DC 20037, USA. larissa.may@gmail.com
authors: Larissa
authors: L
authors: May
authors: Marianne
authors: M
authors: Carim
authors: Kabir
authors: K
authors: Yadav
mesh_terms: D000328:Adult; D001249:Asthma / Q000453:epidemiology / Q000209:etiology*; D004219:District of Columbia / Q000453:epidemiology; D057286:Electronic Health Records; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D004777:Environment; D006801:Humans; D006813:Humidity / Q000009:adverse effects; D016014:Linear Models; D010126:Ozone / Q000009:adverse effects; D052638:Particulate Matter / Q000009:adverse effects; D011058:Pollen / Q000009:adverse effects; D012141:Respiratory Tract Infections / Q000209:etiology; D012189:Retrospective Studies; D012307:Risk Factors; D013696:Temperature; D014197:Trees
chemical_list: D052638:Particulate Matter; D010126:Ozone