Clinical Effect of FeNO Measurement for Asthma Treatment in Primary Care: A Real-world Cluster-randomised Controlled Trial

Asthma is a chronic inflammatory respiratory disease that affects people of all ages and of both sexes. It is a common disease and is present in 8-10 % of the population. Despite drug treatment, many patients have poor control of their asthma with an impact on quality of life and restriction of daily activities. The purpose of this study in primary care is to investigate if measurement of airway inflammation (FeNO) can improve the treatment results and the overall care of adult patients with asthma. The main question in the study is whether the use of FeNO measurements can reduce the number of deterioration periods. The study is conducted under real clinical conditions where the effect of the intervention is measured (pragmatic intervention study). Eight to twelve primary health care centers with functional asthma / COPD clinics are selected within the Stockholm County and are randomly assigned to two groups with four to six primary health care centers each, an active group and a control group (cluster randomization). Instruments for FeNO measurements are made available to the active group and this group is also trained on FeNO measurements and how the value should be interpreted and used to control the treatment, while the control group continues to take care of their asthma patients as usual. The study can lead to improved treatment decisions and patients gaining an increased understanding of their asthma by being informed on the actual degree of inflammation in the airways. Optimized treatment can provide better asthma control with increased quality of life and fewer periods of deterioration, which results in reduced burden on healthcare and lower costs for patients and society.