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. Aim To investigate the epidemiology of physician-diagnosed COPD in general practice. Design of study Cross-sectional study. Settings A total of 422 general practices in England contributing to the QRESEARCH database. Method 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]; PPConclusion 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.