Geographic variations in prevalence and underdiagnosis of COPD : Results of the IBERPOC multicentre epidemiological study

To ascertain the prevalence, diagnostic level, and treatment of COPD in Spain through a multicenter study comprising seven different geographic areas. This is an epidemiologic, multicenter, population-based study conducted in seven areas of Spain. A total of 4,035 men and women (age range, 40 to 69 years) who were randomly selected from a target population of 236,412 subjects participated in the study. Eligible subjects answered the European Commission for Steel and Coal questionnaire. Spirometry was performed, followed by a bronchodilator test when bronchial obstruction was present. The prevalence of COPD was 9.1% (95% confidence interval [CI], 8.1 to 10.2%), 15% in smokers (95% CI, 12.8 to 17.1%), 12.8% in ex-smokers (95% CI, 10.7 to 14.8%), and 4.1% in nonsmokers (95% CI, 3.3 to 5.1%). The prevalence in men was 14.3% (95% CI, 12.8 to 15. 9%) and 3.9% in women (95% CI, 3.1 to 4.8%). Marked differences were observed between sexes in smoking; the percentage of nonsmokers was 23% in men and 76.3% in women (p 60 years old, had higher educational levels, had > 15 pack-year smoking history, or had symptoms of chronic bronchitis. COPD is a very frequent disease in Spain, and presents significant geographic variations and a very low level of previous diagnosis and treatment, even in the most advanced cases.