Figure 2.

Participants with chronic obstructive pulmonary disease, without identifiable appropriate indication for inhaled corticosteroid (ICS), were observed by research staff using a metered-dose inhaler, and their technique was compared with manufacturer’s recommendation for correct sequence and procedure. For each individual step, we present adjusted prevalence ratios (APRs) measuring the association between failure to perform that step correctly and ICS overuse. Prevalence ratios were adjusted for potential confounders, including patient demographics (age, race, and sex), specific comorbidities associated with dyspnea (coronary artery disease, congestive heart failure, and obesity), disease severity (forced expiratory volume in 1 second), symptom severity (modified Medical Research Council dyspnea scale), and spacer use. Failure to exhale before activation, to close lips around mouthpiece, and to repeat sequence for a second inhalation were individually associated with increased likelihood of ICS overuse. Percentages reported in the table reflect the proportion of patients with ICS overuse among those who performed the step correctly or incorrectly. *Adjusted for age, gender, race, congestive heart failure, coronary artery disease, obesity, mMRC score, GOLD Stage of airflow obstruction, and spacer use. CI = confidence interval; GOLD = Global Initiative for Chronic Obstructive Lung Disease; mMRC = modified Medical Research Council.