Spirometry in the primary care setting: influence on clinical diagnosis and management of airflow obstruction.

STUDY OBJECTIVE: To determine if screening spirometry in the primary care setting influences the physician's diagnosis and management of obstructive lung disease. DESIGN: Diagnosis and management assessed before and after the intervention of screening spirometry. PARTICIPANTS: A total of 1,034 patients who had ever smoked and were at least 35 years of age presenting to primary care practices for any reason. SETTING: Rural primary care practices. MEASUREMENTS AND RESULTS: Physicians were asked prior to and following presentation of spirometry test results if they thought airflow obstruction was present and if they planned to change management based on the results. A new diagnosis of unsuspected airflow obstruction was made by the physician in 93 patients (9%), and a prior diagnosis of airflow obstruction was removed after spirometry in 115 patients (11%). After viewing the spirometry results, physicians reported that they would change patient management in 154 patients (15%). Most planned management changes occurred when airflow obstruction was newly diagnosed (57 of 93 patients, 61%) and when the diagnosis of airflow obstruction remained unchanged (80 of 195 patients, 41%). A 6-month chart review documented the addition of respiratory medications in 8% of patients. CONCLUSION: Screening spirometry influences physicians' diagnosis of airflow obstruction and management plans especially in patients with moderate-to-severe obstruction.