Current guidelines on diagnosis and management of asthma are flawed at both the personalised and population levels, according to a group of Australian and international experts.
The group, which includes Professor Peter Gibson of Newcastle University, NSW, and Professor Richard Beasley of the Medical Research Institute of New Zealand, have proposed a new combined approach aimed at improving outcomes.
“Despite major advancements in asthma management and therapies, and the introduction of care pathways, hospital admission rates continue to be higher than expected, and tragically preventable deaths from asthma still occur in young people,” they wrote in The Lancet Respiratory Medicine.
In their paper they argue that these persistent high asthma mortality and morbidity rates are due to the current approach to diagnosis and management of asthma based on symptoms and basic lung function tests.
“This approach is flawed because the inadequate specificity of symptoms, as well as the low sensitivity of variable airflow obstruction, means that a diagnosis of asthma is often difficult to exclude with confidence,” they said.
“Moreover, even if diagnosed correctly, dissociation between inflammation, airflow obstruction, and symptoms means that a generalised stepwise approach to managing asthma on the basis of symptoms is unlikely to be successful in a substantial proportion of patients. As a result, effective treatments are used inefficiently, and outcomes are often worse than they could be.”
They therefore conclude that a major change in asthma guidelines is needed, which builds on important evidence and moves away from a general stepwise approach on managing asthma on the basis of symptoms.
They recommend that initial assessments should be based on history and physical examination as well as demonstration of variable airflow obstruction, as per current guidance from the British Thoracic Society-Scottish Intercollegiate Guidelines Network. Initial treatment, though, should include the combination of low-dose inhaled corticosteroids and rapid-onset β-agonists given as needed, an approach known as anti-inflammatory reliever therapy.
“Regular inhaled corticosteroids are a less attractive initial candidate because the response to treatment is slow, adherence is poor, and there is evidence of potential net harm in patients with a blood eosinophil count below 150 cells per μL,” the authors noted.
If symptoms do not improve over several weeks or months, it should then be determined whether asthma is the wrong diagnosis, if the asthma is refractory, or if other factors are involved. This is an important step before simply escalating treatment. Early measurement of spirometry and type 2 airway inflammation biomarkers will allow more precise and evidence-based treatment decisions.
The use of digital inhaler technologies that can record symptoms, inhaler use, and other measures can also assist patients and help identify those who are likely to have persisting type 2 airway inflammation likely requiring escalation to monoclonal antibody therapies. This approach can help prevent unnecessary prolonged exposure to corticosteroids.
“This approach is feasible in primary care and allows for more expensive and resource-demanding assessments to be targeted at individuals for whom they are needed, thereby improving costs and acceptability to patients and clinicians,” the authors wrote.