Distribution and outcomes of the new Spanish phenotype-based guideline for COPD

Rationale : The new Spanish guideline for COPD recommends COPD treatment according to clinical phenotypes, but little is known on the distribution and outcomes of the four suggested phenotypes. Objective : We aimed to determine the distribution of COPD phenotypes and their differences in terms of demographic and clinical outcomes. Methods : We analyzed demographic, clinical and health-care consumption data from the CHAIN study, a multicenter observational cohort of stable well-characterized COPD out-patients in Spain, at baseline and after one year of follow up. Patients were classified as non-exacerbator phenotype (NE), asthma-COPD overlap syndrome (ACOS), frequent exacerbator phenotype with emphysema (EE) or with chronic bronchitis (ECB), according to guideline criteria. Results : Overall, 831 stable COPD patients were evaluated. They were distributed as phenotype NE, 550 (66.2%); ACOS, 125 (15.0%); EE, 38 (4.6%); and ECB, 99 (11.9%). Nineteen (2.3%) COPD patients with frequent exacerbations did not fulfill the criteria for EE nor ECB. At baseline, there were significant differences by age and gender within the four phenotypes, as well as by symptoms, FEV1 and BODE index (all p<0.05). The mean±SD CAT score was the highest 17.1±8.2 in the ECB phenotype compared to the other phenotypes (p<0.05). Both EE and ECB were more frequently receiving treatment at baseline with long-acting antimuscarinics, inhaled corticosteroids, beta2-agonists and theophyillines, and also experienced more exacerbations after one year of follow-up (all p<0.05). Conclusions : There is an uneven distribution of COPD phenotypes in stable COPD patients, with significant clinical and use of health resources differences.