title: Identifying Risk of Future Asthma Attacks Using UK Medical Record Data: A Respiratory Effectiveness Group Initiative.
abstract: BACKGROUND
  Asthma attacks are common, serious, and costly. Individual factors associated with attacks, such as poor symptom control, are not robust predictors.
  
  
  OBJECTIVE
  We investigated whether the rich data available in UK electronic medical records could identify patients at risk of recurrent attacks.
  
  
  METHODS
  We analyzed anonymized, longitudinal medical records of 118,981 patients with actively treated asthma (ages 12-80 years) and 3 or more years of data. Potential risk factors during 1 baseline year were evaluated using univariable (simple) logistic regression for outcomes of 2 or more and 4 or more attacks during the following 2-year period. Predictors with significant univariable association (P < .05) were entered into multiple logistic regression analysis with backward stepwise selection of the model including all significant independent predictors. The predictive accuracy of the multivariable models was assessed.
  
  
  RESULTS
  Independent predictors associated with future attacks included baseline-year markers of attacks (acute oral corticosteroid courses, emergency visits), more frequent reliever use and health care utilization, worse lung function, current smoking, blood eosinophilia, rhinitis, nasal polyps, eczema, gastroesophageal reflux disease, obesity, older age, and being female. The number of oral corticosteroid courses had the strongest association. The final cross-validated models incorporated 19 and 16 risk factors for 2 or more and 4 or more attacks over 2 years, respectively, with areas under the curve of 0.785 (95% CI, 0.780-0.789) and 0.867 (95% CI, 0.860-0.873), respectively.
  
  
  CONCLUSIONS
  Routinely collected data could be used proactively via automated searches to identify individuals at risk of recurrent asthma attacks. Further research is needed to assess the impact of such knowledge on clinical prognosis.
authors.affiliation: Clinical Sciences, Liverpool School of Tropical Medicine, and Respiratory Medicine, Royal Liverpool Hospital, Liverpool, United Kingdom. Electronic address: John.Blakey@lstmed.ac.uk.
authors.forename: John D
authors.initials: JD
authors.lastname: Blakey
authors.affiliation: Academic Primary Care, University of Aberdeen, Aberdeen, United Kingdom; Observational and Pragmatic Research Institute Pte Ltd, Singapore.
authors.forename: David B
authors.initials: DB
authors.lastname: Price
authors.affiliation: NUPAIVA (Asthma Research Centre), University Hospital, Federal University of Santa Catarina, Florianуpolis, Santa Catarina, Brazil.
authors.forename: Emilio
authors.initials: E
authors.lastname: Pizzichini
authors.affiliation: Medical University Sofia, Sofia, Bulgaria.
authors.forename: Todor A
authors.initials: TA
authors.lastname: Popov
authors.affiliation: Primary Care and Population Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; NIHR Southampton Respiratory Biomedical Research Unit, Southampton, United Kingdom.
authors.forename: Borislav D
authors.initials: BD
authors.lastname: Dimitrov
authors.affiliation: Department of Pulmonology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
authors.forename: Dirkje S
authors.initials: DS
authors.lastname: Postma
authors.affiliation: Primary Care and Population Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom.
authors.forename: Lynn K
authors.initials: LK
authors.lastname: Josephs
authors.affiliation: Department of Family and Community Medicine, University of Toronto, Toronto, Canada.
authors.forename: Alan
authors.initials: A
authors.lastname: Kaplan
authors.affiliation: Department of Medicine, University of Ferrara, Ferrara, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Papi
authors.affiliation: Observational and Pragmatic Research Institute Pte Ltd, Singapore.
authors.forename: Marjan
authors.initials: M
authors.lastname: Kerkhof
authors.affiliation: Observational and Pragmatic Research Institute Pte Ltd, Singapore.
authors.forename: Elizabeth V
authors.initials: EV
authors.lastname: Hillyer
authors.affiliation: Respiratory Effectiveness Group, Cambridge, United Kingdom.
authors.forename: Alison
authors.initials: A
authors.lastname: Chisholm
authors.affiliation: Primary Care and Population Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; NIHR Southampton Respiratory Biomedical Research Unit, Southampton, United Kingdom.
authors.forename: Mike
authors.initials: M
authors.lastname: Thomas
mesh_terms: D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000322:Adrenergic Agonists / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000188:drug therapy / Q000453:epidemiology*; D002648:Child; D016208:Databases, Factual; D004636:Emergency Service, Hospital; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D008954:Models, Biological; D012008:Recurrence; D012307:Risk Factors; D006113:United Kingdom; D055815:Young Adult
chemical_list: D000305:Adrenal Cortex Hormones; D000322:Adrenergic Agonists
keywords: Asthma; Attack; Control; Medical record; Observational; Risk factor