Safety of bronchodilator reversibility test in elderly subjects: a prospective study

Introduction
The reversibility test measures an increase in ventilation parameters after the administration of 400 mg of a short-acting b-agonist (SABA). It is worth noting that a typical dosage, applied as a rescue medicine for bronchospastic dyspnoea, is significantly less, i.e., 100–200 mg.

Aim
To assess the effects of inhaled 400 mg fenoterol (in the bronchodilator reversibility test) on the heart rate and the development of tachyarrhythmias in subjects aged 65 and above.

Material and methods
A total of 53 subjects (45 women) aged 77; 68–82 (median; interquartile range) in stable clinical condition were included in the study. Data including medical history, physical examinations, blood biochemistry, chest X-ray, 12-lead electrocardiogram, 24-hour Holter ECG monitoring, bronchodilator test, and echocardiography were obtained. During the Holter ECG monitoring, the bronchodilator test using 400 mg fenoterol (Berotec pMDI) was performed.

Results
A slight but statistically significant (p = 0.02) increase in heart rate from 71 to 75 per min (median) was noted after the administration of fenoterol. No statistically significant differences were found in the number of extrasystolic beats of either supraventricular (p = 0.42) or ventricular origin (p = 0.50). In addition, the subjects did not show any potentially dangerous arrhythmias or significant signs of coronary artery disease. However, there was a significant increase in the number of supraventricular beats in the subjects who were not taking β-blockers.

Conclusions
The use of 400 mg fenoterol in a bronchodilator reversibility test in elderly subjects does not entail any significant cardiovascular risk.