Diagnostic Error in Asthma and COPD Patients

Studies suggesting anywhere from 30% to 50% of patients may be misdiagnosed with asthma or chronic obstructive pulmonary disease (COPD) led to a $1.5 million grant to examine the impact ofdiagnostic erroron patient outcomes and the use of spirometry testing in primary care.

Spirometry tests evaluate lung function by measuring how much and how fast a patient can push air out of their lungs. The test involves a patient taking a deep breath and exhaling as hard and as long as possible into the machine.

It is both the nationally and internationally recommended test for diagnosing COPD and asthma.

“Despite the clinical guidelines supporting the use of spirometry to identify asthma and COPD, many patients do not receive the test prior to receiving a diagnosis,” said principal study investigator Min Joo.

Patients who go without a spirometry test run the risk for worse sickness and even death, according to Joo. Additionally, they are more prone to unnecessary medical costs that disproportionately affect African Americans and other minority populations.

“A shocking number of patients are diagnosed and face a 2-fold danger,” Joo said. “First, they are taking medication for a condition they may not have, creating unnecessary exposure to the side effects and complications of those medications, such a pneumonia from using inhaled corticosteroids. Second, their real conditions are left unidentified and untreated. This may be particularly true for minority and underserved populations who are known to have multi-morbidities and therefore have a number of potential causes for shortness of breath and other breathing-related issues.”

A finding from a previous study revealed that up to 65% of COPD patients who were seen in a federally qualified health center ended up not having COPD after all once they were given spirometry test.

“In the past, attempts to increase the use of spirometry in a primary care setting have had limited long term success, and a new approach is needed to reduce diagnostic error and better understand its impact on patient safety and outcomes,” Joo said. “Our study will test an approach that relies on trained community health workers to facilitate the test, educate patients, and work with primary care physicians.”

The Reducing Diagnostic Error to Improve Patient Safety in COPD and Asthma (REDEFINE) study is a 3-year clinical trial that will enroll 400 adults diagnosed with asthma and/or COPD, but who have not had spirometry testing, and 60 primary care providers.

One group will receive spirometry testing and will be provided with recommended patient education from trained community health workers around the time of their primary care visits. Those in the control group will receive usual care and education from community health workers, but will not undergo spirometry testing.

Each of the groups will be followed for a year, at which the control group will be given a spirometry test to confirm each participant’s initial diagnosis.

In order to evaluate the efficacy of the program, data will be collected on the prevalence of diagnostic error, the efficiency of the REDEFINE program’s intervention on patient-centered outcomes, and the cost of the program.

“We will look at the key indicators of misdiagnosis and poor outcomes for asthma and COPD,” Joo said. “Specifically, we want to track use of respiratory medication, acute visits to primary care physicians, emergency department visits, and hospitalizations. We hope to see these numbers reduced for patients who receive our intervention.”

The grant was given by the Agency for Healthcare Research and Quality.