At least two thirds of patients with chronic obstructive pulmonary disease (COPD) do not receive lung function testing that is recommended for the accurate diagnosis and effective management of the disease, suggesting that the majority of patients are diagnosed with COPD based on symptoms alone. New research published in the June issue of CHEST, the peer-reviewed journal of the American College of Chest Physicians (ACCP), finds that only one third of patients recently diagnosed with COPD underwent spirometry, a noninvasive lung function test, to confirm COPD or to manage their condition. Current national guidelines recommend spirometry for the diagnosis and management of COPD.

"Spirometry testing is necessary for the diagnosis and staging of COPD, yet the majority of patients with COPD are being diagnosed based on symptoms and smoking history," says Todd A. Lee, PharmD, PhD, Hines VA Hospital, Hines, Ill. "While these patients may indeed have COPD, spirometry is needed to make a definite diagnosis. As a result, patients who do not have COPD may be receiving unnecessary chronic therapy."

Lee and colleagues examined the use of spirometry among 197,878 patients (98 percent men) from the Veterans Health Administration (VHA) healthcare system who were newly diagnosed with COPD. Patient records were reviewed for the general use of spirometry and spirometry related to exacerbation or surgery over a 12-month period. Of the patients, 33.7 percent had at least one spirometry through the VHA over the course of a year. A random sample of 6,000 patients revealed an additional 4.3 percent of patients underwent spirometry in non-VHA settings. Among patients who experienced acute exacerbation of COPD, spirometry was performed only 21.4 percent of the time, despite current guidelines that recommend spirometry four to six weeks after an exacerbation. Spirometry was used most frequently around surgical procedures that required general anesthesia, with 85.5 percent of patients having spirometry performed 30 days or less before their procedure.

A pulmonary clinic visit was the factor that had the highest association with having a spirometry test. Patients seen by a pulmonologist were three times more likely to have a spirometry test than those with no pulmonary visit. Younger age was significantly associated with the likelihood of having spirometry performed. Compared to patients younger than 50 years old, the likelihood of having a spirometry performed was 18 percent lower in those 60 to 69 years old, 32 percent lower in those 70 to 79 years old, and 48 percent lower in those 80 years or older. In addition, mental health and substance abuse diagnosis were also associated with lower likelihood of having spirometry performed.

"Providers may be more reluctant to use spirometry in older patients because of concerns about the validity and acceptability of the test results," says Lee. "Providers also may be interested in a definitive diagnosis for younger patients that are experiencing symptoms associated with COPD and thus refer these patients for spirometry." Although the role of spirometry in routine clinical practice remains unclear, researchers believe there is a need to increase the training and use of lung function testing in the primary care setting.

"COPD is a highly preventable disease most commonly caused by long-term smoking," says W. Michael Alberts, MD, FCCP, president of the ACCP. "Symptoms of COPD may not be noticeable for several years, making it difficult to diagnose and treat the disease in its early stages. Lung function testing for smokers and other high-risk patients may help with early identification of COPD and more effective disease management."

Source: ACCP