Prevalence of chronic obstructive pulmonary disease in the Canary Islands.

INTRODUCTION The prevalence of chronic obstructive pulmonary disease (COPD) varies significantly among the different geographical areas reported. In Spain, two epidemiological studies have shown a prevalence of 9-10% in the population aged over 40. However, neither of these studies included the Canary Islands, which are of interest due to their climatic conditions and high incidence of smoking. MATERIALS AND METHODS A random group of 1,353 subjects aged between 40 and 70years was selected from a sample population of 596,478 individuals. Participants completed a questionnaire and then performed spirometry with bronchodilator testing if obstruction was observed. COPD was diagnosed when the post-bronchodilator FEV1/FVC ratio was less than 0.70. RESULTS The prevalence of COPD was 7.3% (95%CI: 5.5-9.5) and was higher in males than in females (8.7% vs. 6.3%, P=.134). The incidence of smoking was 29.4% (95%CI: 25.4-33.1) and was also higher in males than in females (35.1% vs 25.4%, P<.001). The prevalence of COPD stratified by severity of obstruction, according to the GOLD criteria, was 16% in groupi, 69.9% in groupii, 10.4% in groupiii and 3.3% in groupiv. 71.6% of the subjects were underdiagnosed and 63.5% undertreated. CONCLUSIONS Despite having one of the highest rates of smoking in Spain, the prevalence of COPD in the Canary Islands is lower than in most of the Spanish regions studied.