Changes in determination of bronchodilator response in patients diagnosed with asthma

<bold>Introduction:</bold> bronchodilator response is often used in the diagnosis of asthma. In 2005 Pellegrino et al1 published interpretation strategies for spirometry, bronchodilator response (BR) was defined as an increase of 12% in FEV1 and 200ml, based on the measured values. In 2021 an update was published by Stanojevic et al 2 defining BR as an increase of 10% of the predicted value. <bold>Methods:</bold> data were obtained from the database in a general hospital. 123 patients with a new diagnosis of asthma, who performed spirometry (pre and post medication, SABA) were included in the analysis. BR was calculated using Excel. A chi-square test was performed to define any statistical differences using SPSS (Version 28). <bold>Results:</bold> characteristics are shown in table 1. Using the 2005 definition 23 patients showed a BR, with the 2021 definition 24 patients demonstrated a response. Figure 1 shows the difference in response between both methods. The chi-square test showed no significant difference. <table-wrap><object-id>erj;64/suppl_68/PA3919/T1</object-id><object-id>T1</object-id><object-id>t1</object-id><table><colgroup><col></col><col></col><col></col></colgroup><tbody><tr><td></td><td><bold>Male (N = 45)</bold></td><td><bold>Female (N =78)</bold></td></tr><tr><td><bold>Age (y)</bold></td><td>52 (18)</td><td>50 (16)</td></tr><tr><td><bold>FEV1 pre (L)</bold></td><td>3,1 (0,8)</td><td>2,4 (0,7)</td></tr><tr><td><bold>FEV1 pre (%)</bold></td><td>85,7 (15,7)</td><td>87,7 (16,3)</td></tr><tr><td><bold>FEV1 post(L)</bold></td><td>3,4 (0,9)</td><td>2,6 (0,7)</td></tr><tr><td><bold>FEV1 post (%)</bold></td><td>92,4 (11,4)</td><td>94 (16,8)</td></tr><tr><td><bold>Change 2005 (%)</bold></td><td>8,3 (7,6)</td><td>7,7 (8,2)</td></tr><tr><td><bold>Change 2021 (%)</bold></td><td>6,7 (5,7)</td><td>6,3 (5,7)</td></tr></tbody></table></table-wrap> <fig><object-id>erj;64/suppl_68/PA3919/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig> <bold>Conclusion:</bold> Using the new cut-off values in the determination of BR resulted in minor differences of BR in comparison with the 2005 values.