Abstract
Idiopathic pulmonary fibrosis (IPF) is progressive with a median survival of 2-3yrs. The natural history is highly variable and difficult to predict for an individual presenting with early IPF.
Aim: To identify markers associated with disease progression for IPF patients; especially those with early disease.
Method: The Australian IPF Registry recruits IPF patients across Australia collating clinical, physiological and questionnaire data. Using this real-world longitudinal cohort we compared mild disease(FVC >80%) with FVC<80%. Using Cox analysis and logistic regression,we examined associations between pre-specified markers and progression free survival(PFS;fall in FVC>10% or DLco>15% ± death).
Result: Baseline data in 631 participants revealed: 433(69%) male, mean age 70.1±8.5yrs; mean FVC 81±22% and DLco 49±17%. Patients with mild disease(n=235) were older(p=0.001) and more often female(p<0.001), than those with FVC<80%.
Reduced PFS was associated with: male gender, impaired quality of life(SGRQ), depression, cough severity, and lower baseline FVC and DLco. Patients with mild disease had improved PFS compared to those with FVC<80%(HR 1.61;95% CI1.3,2.0;P<0.001).
In the subset of patients with mild disease, 41 (18%) had disease progression at 12mths. In mild IPF, disease progression at 12mths was associated with: 6MWT end SpO2 (OR 0.91, 95%CI 0.84-0.99; p=0.028), 6MWT distance and cough severity. On multivariate regression, the variable most closely associated with death at 12mths was 6MWT end SpO2.
Conclusion: Impaired baseline lung function is associated with a worse PFS in IPF patients. However a significant proportion of patients with mild disease also show disease progression at 12mths.
- Copyright ©the authors 2016
