Currently, around 32,000 people in the UK have the severe and chronic lung disease idiopathic pulmonary fibrosis (IPF) which is characterised by progressive and irreversible scarring of the lungs. Approximately 6,000 people are diagnosed with IPF each year. Medications for IPF developed specifically to reduce the progression of scarring of the lungs have been available since 2011. Two antifibrotic medications have been shown to slow the rate of lung function decline in IPF, but whether they increase survival remains unclear with conflicting reports.
This study will use the Clinical Practice Research Datalink to investigate whether the use of these two medications that reduce scarring in IPF is associated with a longer survival. This study will provide much needed information on the effectiveness of these medications on survival, which will be of value to health agencies, doctors, and patients.
Recent observational studies have reported that the use of the antifibrotics pirfenidone and nintedanib is associated with lower mortality in patients with idiopathic pulmonary fibrosis (IPF), in contrast with randomized trials that report conflicting data on mortality with these drugs. However, the observational studies were shown to be affected by immortal time bias which tends to exaggerate the effectiveness of drugs. To date, no well-designed observational study that avoids this bias and with a sufficiently large sample size and follow-up has investigated the effectiveness of antifibrotics for IPF on mortality. Thus, the primary objective of this study will be to assess the association between antifibrotics and all-cause mortality in a cohort of patients with IPF at least 40 years of age and newly diagnosed with IPF on or after January 1, 2003, until December 31, 2020. A prevalent new-user cohort design will be used by which patients with IPF initiating antifibrotics will be matched to non-users using time-conditional propensity scores. All patients will be followed until death, lung transplant, end of registration with the practice, or end of the study period (December 31, 2021). Cox proportional hazard models will be used to estimate hazard ratios and 95% confidence intervals of death associated with the use of antifibrotics when compared to non-use, controlling for informative censoring.
All-cause and respiratory-related mortality
Samy Suissa - Chief Investigator - Sir Mortimer B Davis Jewish General Hospital
Samy Suissa - Corresponding Applicant - Sir Mortimer B Davis Jewish General Hospital
Deborah Assayag - Collaborator - Research Institute of the McGill University Health Centre
Sophie Dell'Aniello - Collaborator - McGill University
Tanja Tran - Collaborator - UCB Biopharma SRL - Belgium Headquarters
HES Admitted Patient Care;ONS Death Registration Data