After evaluating chronic obstructive pulmonary disease patients with spirometry, considered to be the final word in the diagnosis of the disease, researchers have found that two in five patients currently receiving treatment at a federally funded clinic do not have the disease.
"While there have been many studies of the under-diagnosis of COPD, there has not been a U.S.-based study that has quantified the problem of over-diagnosis," said Christian Ghattas, MD., MSc, a second-year medical resident at Saint Elizabeth Health Center in Youngstown, Ohio, who will present the research at ATS 2013. "And yet, the cost of treating someone for COPD is high."
A survey published in 2003 in Respiratory Medicine found the average cost of treating a patient with COPD in the United States was $4,119 per year.
Between February 2011 to June 2012, researchers evaluated 80 patients had been given either a diagnosis of COPD or had been prescribed an anticholinergic inhaler, a therapy used to treat COPD symptoms, usually by a primary health care providers.Among those who received the diagnosis were three patients under the age of 35 and five patients who had never smoked—members of demographic groups unlikely to have COPD. Despite the Global Obstructive Lung Disease (GOLD) recommendation that no COPD diagnosis be made without spirometry, only 17.5 percent of patients had been given the test.
As part of this study, all 80 patients underwent spirometry performed by trained professionals following American Thoracic Society recommendations. Results showed that 42.5 percent of patients had no obstruction at all, so by definition, did not have COPD. Another 23 percent had reversible obstruction, more characteristic of asthma than COPD. Only 35 percent of the patients had non-reversible obstruction, a defining characteristic of COPD.
Dr. Ghattas said he and his colleagues undertook the study because he had known patients with a COPD diagnosis who came to his clinic and were seen in the emergency department clutching their inhalers, but never seeming to get better.
"We were shocked at the percentage," Dr. Ghattas said, adding that the true rate of misdiagnosis was probably closer to half. Although they did not evaluate the 23 percent with reversible obstruction further, the investigators felt certain that many of those patients were misdiagnosed with COPD.
"This study confirms that symptoms alone are insufficient to make a COPD diagnosis," said Dr. Awad.. "Shortness of breath, cough, and sputum production can indicate other respiratory problems like allergies—or they may be symptoms of a heart problems or of simply being overweight"
The average age of a study participant was 53 years, with a 38-year-smoking-pack history. Most of the participants were female (60 percent), Caucasian (88.8 percent) and uninsured (71.3 percent).
Both Drs. Ghattas and Awad believe that studies like theirs should be conducted in other settings with different patient populations.
"Although the number of patients in our study was small, I believe this study is representative of an uninsured and underserved patient population," Dr. Ghattas said, "However, the findings might be different among patients who are insured. They might be higher or lower—we simply don't know."
Such studies, the investigators agree, are likely to pay for themselves by reducing unnecessary medical expenses. Presented with the results of this study, the Axess Pointe Board of Directors, decided to offer spirometry to uninsured patients on a sliding scale, with most patients paying just $5 for the test.
When it comes to properly diagnosing COPD, the benefits to patients' physical and mental health may be even greater than the savings to the healthcare system, the researchers believe.
"It is obviously detrimental to be on medications that won't work for you," said Dr. Ghattas. "You won't feel better—and that by itself can take a psychological toll— and you may experience side effects that can compromise other aspects of your health."