Physical activity is associated with disease severity in idiopathic pulmonary fibrosis: a cross-sectional study

Abstract BackgroundPhysical inactivity is associated with poor outcomes in patients with many chronic lung diseases, however little is known about physical activity in patients with idiopathic pulmonary fibrosis (IPF). Our aim was to describe daily physical activity (DPA) in patients with a confirmed diagnosis of IPF and analyse its associations with traditional markers of disease severity and quality of life.MethodsFifty-nine patients with IPF had DPA parameters and sedentary time assessed with the Sensewear armband for seven consecutive days. Participants completed the Hospital Anxiety and Depression scale (HADS), St Georges Respiratory Questionnaire (SGRQ) and Leicester Cough Questionnaire (LCQ). Data on current markers of disease severity; forced vital capacity (FVC), carbon monoxide diffusion capacity (DLCO) and 6-minute walk test (6MWT) as well as prognostic markers; composite physiologic index (CPI) and gender age and physiology (GAP) was collected.ResultsPatients had a median daily step count of 3957 (300–7614), mean daily moderate to vigorous (MV) physical activity duration of 8.6 minutes (-13.1 to 30.3) and mean total daily sedentary time of 1234.6 minutes (± 122.8). Patients with early stages of IPF according to GAP stage had significantly higher daily step count than those with more severe disease (p < 0.003). Age, BMI and DLCO accounted for 54% variability in physical activity duration. The 6-minute walk distance and DLCO accounted for 44% variability in daily step count. Patient reported outcomes had weak association with daily step count and MV physical activity duration.ConclusionIn IPF, increasing disease severity is associated with reduced DPA. DPA may be a meaningful outcome for future trials of therapies designed to enhance patient functioning and wellbeing.Trial Registration: please note that a request has been made for retrospective registration with the Australian New Zealand Clinical Trial Registry with the request number being 381161. Due to holiday period closure, this is yet to be processed. I will supply this as soon as accepted.