title: Trends in the epidemiology of chronic obstructive pulmonary disease in England: a national study of 51 804 patients.
abstract: BACKGROUND
  Patients with chronic obstructive pulmonary disease (COPD) constitute a substantial burden to healthcare services. Analysis of national healthcare datasets offers the possibility to advance understanding about the changing epidemiology of COPD.
  
  
  OBJECTIVE
  To investigate the epidemiology of physician-diagnosed COPD in general practice.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  A total of 422 general practices in England contributing to the QRESEARCH database.
  
  
  METHODS
  Data were extracted on 2.8 million patients, including age, sex, socioeconomic status, and geographical area. Trends over time for recorded physician diagnosis of COPD were analysed (2001-2005).
  
  
  RESULTS
  There was little change over time in the incidence rate of COPD (2005: 2.0 per 1000 patient-years, 95% confidence interval [CI] = 2.0 to 2.1), but a significant increase in lifetime prevalence rate (2001: 13.5 per 1000 patients [95% CI = 13.4 to 13.7]; 2005: 16.8 [95% CI = 16.7 to 17.0]; P<0.001). In 2005, 51 804 individuals or one in 59 people in England were recorded with physician-diagnosed COPD. The most deprived people (31.1 per 1000 patients; 95% CI = 30.6 to 31.7) and those living in the north east of England (29.2 per 1000 patients; 95% CI = 28.4 to 30.1) had the highest prevalence. The observed reduction in the rate of smoking by patients with COPD (overall decrease: 2.5%; P<0.001) varied according to socioeconomic group (most affluent: 6.5% decrease, most deprived: 1.3% decrease).
  
  
  CONCLUSIONS
  Given the peak in the incidence rate of COPD, we may be approaching the summit of COPD incidence and prevalence in England. However, the number of people affected remains high and poses a major challenge for health services, particularly those in the north east of the country and in the most deprived communities in England. The very limited decrease in smoking rates among the more deprived groups of patients with COPD is also a cause for concern.
authors.affiliation: Allergy and Respiratory Research Group, Centre for Population Health Sciences, University of Edinburgh, Medical School (Doorway 3), Teviot Place, Edinburgh. c.simpson@ed.ac.uk
authors.forename: Colin R
authors.initials: CR
authors.lastname: Simpson
authors.forename: Julia
authors.initials: J
authors.lastname: Hippisley-Cox
authors.forename: Aziz
authors.initials: A
authors.lastname: Sheikh
mesh_terms: D003430:Cross-Sectional Studies; D004739:England / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology*; D012111:Residence Characteristics; D012907:Smoking / Q000453:epidemiology; D012959:Socioeconomic Factors