PURPOSE: α1-Antitrypsin deficiency (α1-ATD) is a serious genetic disorder estimated to affect up to 100,000 Americans. The disorder is underrecognized, with frequent long delays (ie, 5-7 years or more) between onset of symptoms and initial diagnosis. This study, conducted by the Respiratory & Allergic Disease Foundation, sought to determine whether a testing protocol in adult patients with persistent asthma and/or chronic obstructive pulmonary disease (COPD) would uncover patients with α1-ATD, who would thus require further investigation.
METHODS: Over a 1-month period, 40 office-based pulmonologists across the United States tested a total of 454 adult patients with persistent asthma and/or COPD and loss of lung function, defined by either a forced expiratory volume at 1 second (FEV1) or a ratio of FEV1 to forced vital capacity (FEV1/FVC) <70%. Blood serum α1-antitrypsin (α1-AT) levels were initially assessed. Lab results and detailed patient histories were reported and tabulated. Physicians reporting patients with low α1-AT levels were asked to determine the α1-AT Pi phenotype.
RESULTS: Fifteen of 454 patients tested (3.3%) showed low α1-AT levels. Multiple abnormal phenotypes were reported. There was no distinguishing feature among this cohort of patients to help identify patients with an abnormal α1-AT level or phenotype. FEV1, FEV1/FVC, and number of bronchial infections in past 12 months were similar between these patients and normal controls.
CONCLUSION: Testing all patients with persistent asthma and/or COPD with FEV1 and/or FEV1/FVC ratio <70% in an office-based setting uncovered patients with abnormal α1-AT levels and phenotypes. These patients are not easily differentiated from other patients with asthma and/or COPD without testing for α1-AT levels.
CLINICAL IMPLICATIONS: All patients with persistent asthma and/or COPD with loss of lung function should be tested for α1-ATD. Recent studies have indicated that α1-ATD is more common than is generally believed by physicians. The testing criteria utilized in this study may be practical in an office-based clinical setting.
DISCLOSURE: Douglas Hogarth, No Product/Research Disclosure Information; University grant monies NA; Grant monies (from industry related sources) Contracted research-Baxter; Shareholder NA; Employee NA; Fiduciary position (of any organization, association, society, etc, other than ACCP NA; Consultant fee, speaker bureau, advisory committee, etc. Consulting fees-CSL Behring and Fees for non-CME Services received directly from a commercial interest-CSL Behring and Talecris.; Other