August 15, 2007 — Spirometry testing is a widely accepted and encouraged diagnostic method for chronic obstructive pulmonary disease (COPD), but new research shows that it is not used nearly enough.
The study appears in the August issue of CHEST, the peer-reviewed journal of the American College of Chest Physicians (ACCP) and reports that only one-third of patients with a COPD diagnosis ever received spirometry testing.
"Without proper testing, both underdiagnosis and misdiagnosis may occur, which can lead to improper therapies being prescribed," said lead author MeiLan Han, MD, MS, University of Michigan, Division of Pulmonary and Critical Care Medicine. "This study shows that we have a lot of work ahead of us in terms of raising awareness among both patients and physicians."
Along with colleagues from Johns Hopkins University, the University of Washington, and the National Committee for Quality Assurance, Dr. Han identified patients with newly diagnosed COPD by data collected from five health plans. The study examined patients aged 40 years and older, and determined if patients with a new diagnosis of COPD had received spirometry in the preceeding 720 days. Of the 5,039 eligible patients identified, only 32% were found to have received spirometry testing. Furthermore, only half of those patients received follow-up bronchodilator testing to confirm their diagnosis.
"In order to distinguish COPD from other diseases, such as asthma, spirometry must be measured both before and after administration of medication that dilates the airways," Dr. Han explained. "As such, if COPD is suspected, initial spirometric testing should include bronchodilator testing too, in order for that patient to receive a truly diagnostic test."
In addition, the study notes that these numbers contradict previous findings in which over 70% of physicians reported using spirometry for establishing a COPD diagnosis. Given the contrast, Dr. Han suggests a possible difference between what physicians say and what they actually do. Also of particular concern was that, according to this study, spirometry testing in those patients who were 75 years and older was performed less frequently, with only 28% of patients in this population receiving spirometry. Researchers point to the issue of ageism and question whether or not a patient's age influences a physician's decision to order diagnostic testing.
"The bad news is that we have significant room for improvement. The good news is that we have to know a problem exists before we can fix it, and now we know," said Dr. Han. Other good news is that women and men fared virtually the same when it came to spirometry testing, despite previous reports suggesting women were tested less often.
For more information: www.chestnet.org