title: Detection of COPD Exacerbations and compliance with patient-reported daily symptom diaries using a smart phone-based information system [corrected].
abstract: BACKGROUND
  Paper-based diaries and self-report of symptom worsening in COPD may lead to underdetection of exacerbations. Epidemiologically, COPD exacerbations exhibit seasonal patterns peaking at year-end. We examined whether the use of a BlackBerry-based daily symptom diary would detect 95% or more of exacerbations and enable characterization of seasonal differences among them.
  
  
  METHODS
  Fifty participants with GOLD (Global Initiative for Chronic Obstructive Lung Disease) stage I to IV COPD began a community-based study in December 2007. Another 30 began in December 2008. Participants transmitted daily symptom diaries using a BlackBerry. Alerts were triggered when symptom changes, missed diary transmissions, or medical care for a respiratory problem occurred. Participant encounters were initiated if COPD exacerbations were suspected. Participants used their BlackBerrys to report returns to normal breathing.
  
  
  RESULTS
  Participants transmitted 99.9% of 28,514 possible daily diaries. All 191 (2.5/participant-year) COPD exacerbations meeting Anthonisen criteria were detected. During 148 of the 191 exacerbations (78%, 1.97/participant-year), patients were hospitalized and/or ordered prednisone, an antibiotic, or both. Respiratory viruses were detected in 78 of the 191 exacerbations (41%). Those coinciding with a respiratory viral infection averaged 12.0 days, and those without averaged 8.9 days (P &lt; .04), with no difference in Anthonisen score. Respiratory symptom scores before exacerbations and after normal breathing return showed no differences. Exacerbations were more frequent during the Christmas period than the rest of the year but were not more frequent than in the rest of winter alone.
  
  
  CONCLUSIONS
  Smartphone-based collection of COPD symptom diaries enables near-complete identification of exacerbations at inception. Exacerbation rates in the Christmas season do not reach levels that necessitate changes in disease management.
authors.affiliation: Firestone Institute for Respiratory Health, McMaster University, Hamilton, ON, Canada. Electronic address: njohnsto@mcmaster.ca.
authors.forename: Neil W
authors.initials: NW
authors.lastname: Johnston
authors.affiliation: Firestone Institute for Respiratory Health, McMaster University, Hamilton, ON, Canada.
authors.forename: Kim
authors.initials: K
authors.lastname: Lambert
authors.affiliation: Firestone Institute for Respiratory Health, McMaster University, Hamilton, ON, Canada.
authors.forename: Patricia
authors.initials: P
authors.lastname: Hussack
authors.affiliation: Respiratory and Inflammation Therapy Area, AstraZeneca, Molndal, Sweden.
authors.forename: Maria Gerhardsson
authors.initials: MG
authors.lastname: de Verdier
authors.affiliation: TranScrip-Partners LLP, Reading, England.
authors.forename: Tim
authors.initials: T
authors.lastname: Higenbottam
authors.affiliation: Respiratory and Inflammation Therapy Area, AstraZeneca, Molndal, Sweden.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Lewis
authors.affiliation: MedImmune LLC, Gaithersburg, MD.
authors.forename: Paul
authors.initials: P
authors.lastname: Newbold
authors.affiliation: Biometrics and Information Sciences, AstraZeneca, Alderley Park, Macclesfield, England.
authors.forename: Martin
authors.initials: M
authors.lastname: Jenkins
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada.
authors.forename: Geoffrey R
authors.initials: GR
authors.lastname: Norman
authors.affiliation: Regional Virology Laboratory, Belfast Health and Social Care Trust, Belfast, Northern Ireland.
authors.forename: Peter V
authors.initials: PV
authors.lastname: Coyle
authors.affiliation: Firestone Institute for Respiratory Health, McMaster University, Hamilton, ON, Canada.
authors.forename: R Andrew
authors.initials: RA
authors.lastname: McIvor
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D040421:Cell Phone; D018450:Disease Progression; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario; D011241:Prednisone / Q000627:therapeutic use; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000188:drug therapy / Q000382:microbiology / Q000503:physiopathology*; D012129:Respiratory Function Tests; D012621:Seasons; D057566:Self Report
chemical_list: D000900:Anti-Bacterial Agents; D005938:Glucocorticoids; D011241:Prednisone