Impact of Undiagnosed Chronic Obstructive Pulmonary Disease and Asthma on Symptoms, Quality of Life, Healthcare Use, and Work Productivity
Emily Gerstein, Jared Bierbrier, G. À. Whitmore, Katherine L. Vandemheen, Céline Bergeron, Louis‐Philippe Boulet, Andréanne Côté, Stephen K. Field, Erika Penz, Andrew McIvor, Catherine Lemière, Samir Gupta, Paul Hernandez, Irvin Mayers, Mohit Bhutani, M. Diane Lougheed, Christopher Licskai, Tanweer Azher, Nicole Ezer, Martha Ainslie, Gonzalo G. Alvarez, Sunita Mulpuru, Shawn D. Aaron
Abstract
Abstract Rationale A significant proportion of individuals with chronic obstructive pulmonary disease (COPD) and asthma remain undiagnosed. Objectives The objective of this study was to evaluate symptoms, quality of life, healthcare use, and work productivity in subjects with undiagnosed COPD or asthma compared with those previously diagnosed, as well as healthy control subjects. Methods This multicenter population-based case-finding study randomly recruited adults with respiratory symptoms who had no previous history of diagnosed lung disease from 17 Canadian centers using random digit dialing. Participants who exceeded symptom thresholds on the Asthma Screening Questionnaire or the COPD Diagnostic Questionnaire underwent pre- and post-bronchodilator spirometry to determine if they met diagnostic criteria for COPD or asthma. Two control groups, a healthy group without respiratory symptoms and a symptomatic group with previously diagnosed COPD or asthma, were similarly recruited. Measurements and Main Results A total of 26,905 symptomatic individuals were interviewed, and 4,272 subjects were eligible. Of these, 2,857 completed pre- and post-bronchodilator spirometry, and 595 (21%) met diagnostic criteria for COPD or asthma. Individuals with undiagnosed COPD or asthma reported greater impact of symptoms on health status and daily activities, worse disease-specific and general quality of life, greater healthcare use, and poorer work productivity than healthy control subjects. Individuals with undiagnosed asthma had symptoms, quality of life, and healthcare use burden similar to those of individuals with previously diagnosed asthma, whereas subjects with undiagnosed COPD were less disabled than those with previously diagnosed COPD. Conclusions Undiagnosed COPD or asthma imposes important, unmeasured burdens on the healthcare system and is associated with poor health status and negative effects on work productivity.