A comparison of daily physical activity profiles between adults with severe asthma and healthy controls.

Severe asthma is associated with a substantial burden of disease including premature death and reduced quality adjusted life years [1]. Care in specialist centres is associated with reduced exacerbation rates and healthcare utilisation, but at the cost of increased use of systemic steroids and increased body mass index (BMI) [2]. Common co-comorbidities such as metabolic syndrome and type 2 diabetes are associated with low levels of moderate-vigorous physical activity (MVPA) [3]. Guidelines recommend that adults accumulate either =150 minutes of moderate intensity activity or =75 minutes of vigorous intensity activity per week, accumulated in bouts of any length [4]. Adults with severe asthma may avoid MVPA due to negative expectations and fear-avoidance beliefs [5]. A few small studies have reported that daily step count and time spent in MVPA may be reduced in adults with severe asthma compared to controls [6–8]. However, results are conflicting when physical activity levels are adjusted for confounders such as age, gender, obesity and smoking [7]. Furthermore, adults with severe asthma have reduced health-related quality of life (HRQoL) but whether physical activity levels impact on HRQoL is unknown [9].