Distribution and Outcomes of a Phenotype- Based Approach to Guide COPD Management: Results from the CHAIN Cohort

Abstract

Rationale The Spanish guideline for COPD (GesEPOC) recommends COPD treatment according to four clinical phenotypes: non-exacerbator phenotype with either chronic bronchitis or emphy- sema (NE), asthma-COPD overlap syndrome (ACOS), frequent exacerbator phenotype with emphysema (FEE) or frequent exacerbator phenotype with chronic bronchitis (FECB). How- ever, little is known on the distribution and outcomes of the four suggested phenotypes. Objective We aimed to determine the distribution of these COPD phenotypes, and their relation with one-year clinical outcomes. Methods We followed a cohort of well-characterized patients with COPD up to one-year. Baseline characteristics, health status (CAT), BODE index, rate of exacerbations and mortality up to one year of follow-up were compared between the four phenotypes. Results Overall, 831 stable COPD patients were evaluated. They were distributed as NE, 550 (66.2%); ACOS, 125 (15.0%); FEE, 38 (4.6%); and FECB, 99 (11.9%); additionally 19 (2.3%) COPD patients with frequent exacerbations did not fulfill the criteria for neither FEE nor FECB. At baseline, there were significant differences in symptoms, FEV 1 and BODE index (all p<0.05). The FECB phenotype had the highest CAT score (17.1±8.2, p<0.05 compared to the other phenotypes). Frequent exacerbator groups (FEE and FECB) were receiving more pharmacological treatment at baseline, and also experienced more exacer- bations the year after (all p<0.05) with no differences in one-year mortality. Most of NE (93%) and half of exacerbators were stable after one year. Conclusions There is an uneven distribution of COPD phenotypes in stable COPD patients, with signifi- cant differences in demographics, patient-centered outcomes and health care resources use.