Can clinical data predict rapid decline of lung function in idiopathic pulmonary fibrosis (IPF) patients

Key feature of IPF is decline in forced vital capacity (FVC) and CO diffusion (DLco), but data on clinical determinants of this change in patients who have established disease are scarce. For a given patient it is unknown if different natural histories represent distinct phenotypes of IPF or if geographic, ethnic or other factors might have influence on progression. The EMPIRE (European Multipartner IPF Registry) is a multicountry IPF register in the CEE region. Out of 1229 patients from the registry 324 with available data on FVC and DLco at inclusion and at 6 months rapid decliners (RD: FVC >10% or DLco >10% in 6 months) and controls (C) were included into the analysis. Clinical characteristics at inclusion were analyzed between groups to find clinical determinants of RD. Average age was 67,4±9.7 years, more males were affected than females (male:female 221:103) most patients had classic signs of UIP on HRCT. Most common comorbidity was hypertension (50.9%), coronary heart disease (20.5%), diabetes (20.1%) and hyperlipidaemia (20.1%). RD of FVC was present in 33.7%, while RD of DLco in 53.3% of patients. Comparison of RD and C patients for smoking status, dyspnoe severity, comorbidities, HRCT pattern, lung function parameters at inclusion, 6 minute walk distance or the presence of pulmonary hypertension did not show any difference between groups. The rate of change in FVC or DLco among IPF patients is highly variable, with 34-53 % of patients showing increased rates of decline in FVC and/or DLco. No clinical characteristics could be identified which can predict rapid decline using the data of EMPIRE registry.