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Introduction: Many people suffer from obstructive pulmonary diseases, such as asthma or chronic obstructive pulmonary disease. To support diagnoses of obstructive pulmonary diseases, spirometry is the most common used method. An alternative method is impulse oscillometry, which researchers have become more interested in lately. The aim of this study was to investigate possible associations between response in impulse oscillometry and spirometry to bronchodilators in relation to respiratory symptoms or respiratory disease diagnosis. Method: A total of 138 Burden of Obstructive Lung Disease (BOLD) -participants and the 3566 Swedish CArdioPulmonary bioImage Study (SCAPIS) -participants performed impulse oscillometry and spirometry before and after inhalation of bronchodilators. For impulse oscillometry, the measurements of the resistance at 5 Hz (R5) and the reactance at 5 Hz were used. The measurements of forced expiratory volume under 1 second (FEV1) were used for spirometry. Results: In the SCAPIS-study, a significant association between the response in R5 with wheezing (15,6 % ± 14,9 % with wheezing vs 10,7 % ± 13,9 % without wheezing) and asthma (16,0 % ± 13,5 % with asthma vs 10,6 % ± 14,0 % without asthma) was observed. The same relationship was found in the response in FEV1 with wheezing and asthma. However, no relationship for the response in R5 with wheezing (8,0 % ± 12,4 % with wheezing vs 6,7 % ± 13,1 % without wheezing) or asthma (5,1 % ± 15,2 % with asthma vs 7,3 % ± 12,4 % without asthma) could be discerned in the BOLD-study. Only a significant association between the response in FEV1 with wheezing and asthma could be observed. Conclusion: The conflicting results regarding response to bronchodilators in impulse oscillometry in relation to asthma and wheezing indicates a continued need for research on impulse oscillometry. This is needed to be able to implement impulse oscillometry clinically in the future.