Diagnostic practices for patients with shortness of breath and presumed obstructive airway disorders: a cross-sectional analysis.

backgroundDyspnea is a common symptom that has many causes, including obstructive airway disorders. We sought to examine previous diagnosis of obstructive airway disorders and other conditions in patients receiving treatment with inhaled medications for shortness of breath in a community setting.

methodsThis cross-sectional study included consecutive patients aged 18 years and older receiving treatment for shortness of breath with inhaled medications for a minimum of 6 months. Study participants were recruited through community pharmacies in Edmonton and Saskatoon, Canada, between February 2009 and February 2012. Previous diagnosis of obstructive airway disorders by a primary care provider was assessed by patient self-report and review of health records. We conducted an assessment (as per guidelines from the American Thoracic Society and the European Respiratory Society), including pulmonary function tests; diagnoses were adjudicated by an expert physician panel (2 respirologists and 1 emergency physician). The agreement between diagnoses derived from pulmonary function tests and diagnoses from primary care providers was evaluated.

resultsA total of 328 patients (median age 50 yr, 57.3% female) underwent assessment; 134 (40.9%) of patients reported ever having a pulmonary function test performed. After adjudication, 138 (42.1%) were diagnosed with asthma only, 86 (26.2%) with chronic obstructive pulmonary disease only and 11 (3.4%) with both. Some patients (93, 28.4%) had no evidence of obstructive airway disorders and 20 (6.1%) had evidence of other conditions that cause shortness of breath, such as heart failure and pulmonary hypertension. Overall, 62 (18.9%) patients could not be assigned a diagnosis.

interpretationIn a group of community-based patients with shortness of breath being treated with inhalers, less than half ever had pulmonary function tests performed, and a considerable proportion had no evidence of lung disease or other conditions. These findings highlight the need for confirmatory testing, including pulmonary function tests, before prescribing inhalers for patients with presumed obstructive airway disorders.