Impact of Undiagnosed Chronic Obstructive Pulmonary Disease and Asthma on Symptoms, Quality of Life, Healthcare Use, and Work Productivity.

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.

Impact of Dyspnea on Adults with Respiratory Symptoms Without a Defined Diagnosis.

BACKGROUND: We investigated dyspnea, its associated risk factors, and its impact on healthcare utilization, quality of life, and work productivity in adults with undiagnosed respiratory symptoms. RESEARCH QUESTION: What is the impact of dyspnea in adults with undiagnosed respiratory symptoms? STUDY DESIGN AND METHODS: This population-based study included 2857 adults who were experiencing respiratory symptoms. These individuals had not been previously diagnosed with any lung conditions and were recruited from 17 Canadian centers using random digit-dialing. Each participant underwent spirometry testing both before and after using a bronchodilator to determine if they met the diagnostic criteria for COPD, asthma, Preserved Ratio Impaired Spirometry (PRISm), or if their spirometry results were normal. An age-matched control group (n= 231) was similarly recruited using random-digit dialing. A dyspnea impact assessment score from 0 to 100 was produced using questions from the COPD Assessment Test and St. George's Respiratory Questionnaire. RESULTS: Individuals with PRISm (n=172) reported more impactful dyspnea (mean score 63.0, 95% CI: 59.5- 66.4) than those with undiagnosed asthma (n=265, mean score 56.6, 95% CI: 53.9-59.3) or undiagnosed COPD (n=330, mean score 57.5, 95% CI: 55.1-59.9). All groups reported significantly more impactful dyspnea compared to controls (mean score 13.8, 95% CI:11.8-15.7). Subject-specific risk factors including age, sex, BMI, smoking, and comorbidities explained 20.6% of the variation in dyspnea. An additional 12.4% of the variation was explained by disease classification and another 1.7% by the severity of lung function impairment assessed with spirometry. After adjusting for age, sex, and BMI, greater dyspnea impact was associated with increased healthcare utilization, lower quality of life, and reduced work productivity. INTERPRETATION: In community-based adults with undiagnosed respiratory symptoms, those identified with PRISm experienced the greatest impact of dyspnea. Dyspnea imposes burdens on the healthcare system and is associated with impaired quality of life and work productivity.