Bronchodilator responsiveness is lower with afternoon and wintertime spirometry: study
Adelaide GP Dr Kerry Hancock said the finding probably reflected that patient lung function was generally worse in winter or in the morning.
Bronchodilator responsiveness falls by 8% for each hour of the day that has elapsed, showing the importance of spirometry timing, UK researchers say.
The retrospective study by Cambridge University Hospitals NHS doctors also found that bronchodilator responsiveness was lower in summer or spring than winter, based on 1620 patients (62% female) with diagnosed or suspected asthma.
The data were collected directly from testing software between 2016 and 2023, they wrote in Thorax last month.
They performed testing before and 20 minutes after inhalation of 400µg of salbutamol delivered via a metered dose inhaler and spacer.
