Primary care physicians diagnose and care for a significant portion of the millions of Americans with asthma and COPD. Yet, debate continues regarding the appropriateness, value, and barriers related to in-office spirometry in primary care practices for management of obstructive lung diseases. Studies show that technically adequate spirometry is possible, that screening spirometry of all primary care patients who smoke can identify COPD and modify some COPD treatment and that spirometry in children can be interpreted in primary care practices. A vignette study suggests that family physicians would use spirometry results to modify management of COPD, but no study has assessed the impact of incorporating spirometry into the everyday management of family medicine patients with existing diagnoses of asthma or COPD, We introduced office spirometry into 12 community-based family medicine practices scattered throughout the United States to assess the impact of onsite spirometry in the management of previously diagnosed COPD or asthma (learn more about COPD). We also assessed thetech-nical adequacy and accuracy of interpretation of the tests performed. This real-world study adds another dimension to published data from other countries.
Using a before-and-after quasiexperimental design, spirometers (Easy One; ndd Medizintechnik AG; Zurich, Switzerland) were introduced into 12 nonacademic family medicine practices without prior use of in-office spirometry. The practices were randomly selected from 35 of the 112 practices of the American Academy of Family Physicians National Research Network that volunteered for this study. From each practice, a physician and the person who would administer spirometry participated in an intensive 2-day training session on performance and interpretation of spirometry led by authors E.I., R.L., P.E., B.Y., and S.S.
The Easy One device was chosen for its modem capacity and stability precluding the requirement of daily calibration. The output was standardized: single “best flow volume loop”, FEV1 and FVC in milliliters and percentage of predicted, the FEV1/ FVC ratio, a grade of the technical adequacy (A through F), and a suggested interpretation of the results. FVC was used in preference to forced expiratory volume in 6 s due to the inclusion of children in the study who frequently reach a plateau prior to 6 s of expiration.
After receiving institutional review board approval, each site spent the next 6 months enrolling patients >7 years old with a previously documented diagnosis of asthma or COPD and were attending the office for an asthma- or COPD-related visit. Thus, spirometry was incorporated into everyday practice rather than being used only as a research tool or screening add-on or a test requiring referral. Prior lung function testing was not required to confirm the diagnosis of asthma or COPD. Only two patients refused to participate.
Enrolled patients provided demographic and disease-related information including current symptoms, perceived severity, and level of disease control. Nursing staff documented current medications on the study forms. Physician visits proceeded as usual without the use of spirometry, and at the end of the visit the physician documented the therapy recommended that day using a list of the common asthma and COPD medications with ranges of dosages. This was the “before” data.
The patient then underwent spirometry, and a copy of the results was reviewed by the family physician who recorded his/her interpretation of the results on the study forms. The physician again saw the patient (during the same visit) for a quick follow-up to discuss test results and make any desired changes to the management plan, which were recorded on the “after” section of the study forms using a medication checklist and for nonmedication changes answering the question: “Would you make any nonmedication changes after seeing the spirometry results? If yes, please describe.” Responses included “more frequent follow-up,” “referral to evaluate a non-COPD diagnosis,” or “repeat spirometry testing in 3 months.” A combination of patient-provided symptom information, spirometry results, and before-and-after medications allowed us to judge whether the medications appeared to be consistent or inconsistent with National Asthma Education and Prevention Program or Global Initiative for Chronic Obstructive Lung Disease guidelines. Read an article about the use of spirometry in the diagnosis of bronchial asthma – https://onlineasthmainhalers.com/diagnosis-of-bronchial-asthma-by-clinical-evaluation-methods-and-materials.html.
Copies of the spirometry results and the family physician’s interpretation were sent to one of the experts for their review and scoring. Technical adequacy of all tracings was scored by P.E. based on published American Thoracic Society and European Respiratory Society criteria as adequate or inadequate. The family physician’s interpretation was assessed as concordant or nonconcordant with the expert’s review (R.L, E.I. or H.B) based on standard criteria for obstruction, restriction, and asthma. “Nonconcordant” results were further subclassified into “obstruction reported but not present,” “obstruction present but not reported,” “obstruction less severe than reported,” or “other abnormality present but not reported.” The concordance between the Easy One reading and the expert review was also assessed.
Statistical Analysis
Simple descriptive statistics were used to assess rates of management change by comparing before-and-after data for medications and nonmedication management, rates of technical adequacy, and rates of agreement. Rates of nonconcordance were compared using x2 and Mantel Haenzel tests.