Evaluation of Changes in Control Status in COPD: An Opportunity for Early Intervention

Background: Control has been proposed as a dynamic tool that can capture changes in the clinical status of patients with COPD.

Methods: This prospective, multicenter, observational study aimed to compare changes in control over a 3-month period with changes in risk level, Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage, and clinical phenotype (nonexacerbator, asthma-COPD overlap, or exacerbator with emphysema or with chronic bronchitis). Control was defined as the presence of low clinical impact, assessed according to the degree of dyspnea, use of rescue medication, physical activity and sputum color, and clinical stability assessed by clinical changes and exacerbations in the last 3 months. Impact and stability were alternatively assessed with COPD Assessment Test (CAT) scores.

Results: We included 354 patients, with a mean FEV₁ of 49.8% ± 16.9%. At 3 months, the proportion of controlled patients was 50.3% according to clinical evaluation and 47.8% according to CAT score. Eighty-seven patients (29.2%) changed their control status as assessed by clinical variables, and 85 patients (28.5%) changed their status according to CAT score. In contrast, the risk level only changed in 26 patients (8.7%) (P < .001), 27 patients (9.1%) experienced changes in their clinical phenotype (P < .001), and 59 patients (19.8%) experienced changes in their GOLD stage (P = .008). Patients who showed an improvement in control status had better CAT scores at the end of follow-up (P < .001).

Conclusions: In only 3 months, almost one-third of patients experienced changes in their control status. Changes in control status were significantly more frequent than changes in phenotype, risk level, and GOLD stage, and resulted in significant changes in health status.