A study presented at CHEST found that a higher than expected number of COPD and asthma patients had abnormally low levels of alpha-1 antitrypsin, suggesting the need for broader criteria for AAT deficiency testing.

Althogh AAT deficiency is estimated to affect as many as 100,000 individuals, 95% are undiagnosed or misdiagnosed as having another form of COPD. Study results announced today on World COPD Day emphasize the importance of focusing attention on the need for wider testing for the disorder.

"All patients with moderate or severe persistent asthma and/or COPD with chronic pulmonary symptoms should be tested for AAT deficiency, said Gary Rachelfsky, MD," a study investigator from UCLA. "Many patients are going undiagnosed or misdiagnosed due to screening criteria and practices."

The study, conducted by the Respiratory & Allergic Disease Foundation, tested 454 patients using simple screening criteria: persistent asthma and/or COPD patients with loss of lung function defined by either FEV1 or ratio of FEV1 to FVC of less than 70%. Blood tests were also performed to assess levels of AAT, and additional lab results and patient histories were noted and tabulated.

Of the participants, 3.3% showed deficient levels of AAT, which is associated with progressive severe emphsema that becomes clinically evident by the third to fourth decade of life.

Patients with low AAT did not significantly differ from the COPD/asthma patients with normal levels of AAT in several pulmonary function criteria, including FEV1, FEV1/FVC, or the number of bronchial infections within the past 12 months, thus underscoring the importance of more rigorous screening.

"Physicians cannot depend on typical patient profiles to asses whether AAT deficiency screeing is necessary. The is no ‘face’ to AAT deficiency, " said D Kyle hogarth, MD, FCCP, assistant professor of medicine, University of Chicago Medical Center and director of the AAT Deficiency Clinical Resource Center.