Discrepancy in the use of confirmatory tests in patients hospitalized with the diagnosis of chronic obstructive pulmonary disease or congestive heart failure

OBJECTIVE: To determine the prevalence of confirmatory use of spirometry in patients admitted to a tertiary-care facility with the diagnosis of chronic obstructive pulmonary disease (COPD), including those with respiratory failure, and compare that to the use of confirmatory 2-dimensional echocardiography (2-D echo) in patients admitted with the diagnosis of congestive heart failure (CHF), to determine preferential confirmatory testing practices. SETTING: Academic tertiary-care hospital. METHODS: A 6-month retrospective review of charts of patients with a primary or secondary discharge diagnosis of COPD, respiratory failure, and CHF, using the appropriate International Classification of Diseases, Ninth Revision, Clinical Modification codes. Pulmonary function and echocardiography laboratory databases were reviewed to determine if the patients had had spirometry or 2-D echo performed during the 8 years prior to the study period. RESULTS: Five hundred fifty-three patients were discharged with the diagnosis of COPD, and 173 patients (31%) had had spirometry. In contrast, 789 patients had the diagnosis of CHF, and a larger proportion of them (619 patients, 78%) had had 2-D echo (p < 0.001). Only 35% of the patients with respiratory failure and COPD had spirometry performed. There were a total of 219 patients with concomitant diagnoses of COPD and CHF. A majority of them (48%) had a 2-D echo as the only confirmatory test, 74 (34%) had both tests performed, 4 (2%) had spirometry only, and 36 (16%) had neither test performed. Of the patients with a diagnosis of COPD who had spirometry, 30% had spirometry findings consistent with restrictive or normal physiology. CONCLUSIONS: A large proportion of patients hospitalized with the diagnosis of COPD have never had a confirmatory test, including those with presumably advanced disease. Compared to patients with CHF, patients with COPD are less likely to have had the confirmatory test performed, even when both conditions coexist. Many patients with the clinical diagnosis of COPD have an inconsistent physiologic diagnosis. To impact the increasingly important problem of COPD, we must raise awareness of the need to confirm its diagnosis and severity with spirometry.