A Real-World Analysis to Create Real-World Change: The Need for an Individualized Approach to Improving Physical Activity in Asthma

“Treatable traits” have been proposed as a new paradigm for the management of airway diseases, particularly complex disease, which aims to apply personalised medicine to each individual to improve outcomes. Moving new treatment approaches from concepts to practice is challenging, but necessary. In an effort to accelerate progress in research and practice relating to the treatable traits approach, the Treatable Traits Down Under International Workshop was convened in Melbourne, Australia in May 2018. Here, we report the key concepts and research questions that emerged in discussions during the meeting. We propose a programme of research that involves gaining international consensus on candidate traits, recognising the prevalence of traits, and identifying a potential hierarchy of traits based on their clinical impact and responsiveness to treatment. We also reflect on research methods and designs that can generate new knowledge related to efficacy of the treatable traits approach and consider multidisciplinary models of care that may aid its implementation into practice.

Asthma is a heterogeneous and complex disease, and a description of asthma phenotypes based on extrapulmonary treatable traits has not been previously reported. The objective of this study was to identify and characterise clusters based on clinical, functional, anthropometrical and psychological characteristics in participants with moderate-to-severe asthma. This was a cross-sectional multicentre study involving centres from Brazil and Australia. Participants (n=296) with moderate-to-severe asthma were consecutively recruited. Physical activity and sedentary time, clinical asthma control, anthropometric data, pulmonary function and psychological and health status were evaluated. Participants were classified by hierarchical cluster analysis and the clusters compared using ANOVA, Kruskal­–Wallis and Chi-squared tests. Multiple logistic and linear regression models were performed to evaluate the association between variables. We identified four clusters: 1) participants with controlled asthma who were physically active; 2) participants with uncontrolled asthma who were physically inactive and more sedentary; 3) participants with uncontrolled asthma and low physical activity, who were also obese and experienced anxiety and/or depression symptoms; and 4) participants with very uncontrolled asthma who were physically inactive, more sedentary, obese and experienced anxiety and/or depression symptoms. Higher levels of sedentary time, female sex and anxiety symptoms were associated with increased odds of exacerbation risk, while being more active showed a protective factor for hospitalisation. Asthma control was associated with sex, the occurrence of exacerbation, physical activity and health status. Physical inactivity, obesity and symptoms of anxiety and/or depression were associated with worse asthma outcomes, and closely and inextricably associated with asthma control. This cluster analysis highlights the importance of assessing extrapulmonary traits to improve personalised management and outcomes for people with moderate and severe asthma.