Mortality and survival in idiopathic pulmonary fibrosis: a systematic review and meta-analysis

Background:There are substantial advances in diagnosis and treatment for idiopathic pulmonary fibrosis (IPF), but without much evidence available on recent mortality and survival trends.

Methods: A narrative synthesis approach was used to investigate the mortality trends, then meta-analyses for survival trends were carried out based on various time periods. Results: Six studies reported the mortality data for IPF in 22 countries, and 62 studies (covering 63,307 patients from 20 countries) reported survival data for IPF. Age-standardised mortality for IPF varied from approximately 0.5 to 12 per 100,000 population per year after year 2000. There were increased mortality trends for IPF in Australia, Brazil, Belgium, Canada, Czech Republic, Finland, France, Germany, Hungary, Italy, Lithuania, Netherlands, Poland, Portugal, Spain, Sweden, and UK, while Austria, Croatia, Denmark, Romania, and US showed decreased mortality trends. The overall 3-year and 5-year cumulative survival rates (CSRs) were 61.8% (95% CI, 58.7-64.9; I2=97.1%) and 45.6% (95% CI, 41.5-49.7; I2=97.7%), respectively. Prior to 2010, the pooled 3-year CSRs was 59.9% (95% CI, 55.8-64.1; I2>95.8%), then not significantly (P=0.067) increased to 66.2% (95% CI, 62.9-69.5; I2=92.6%) in the 2010s decade. After excluding three studies in which no patients received antifibrotics after year 2010, the pooled 3-year CSRs significantly (P=0.039) increased to 67.4% (95% CI, 63.9- 70.9; I2=93.1%) in the 2010s decade.

Discussion: IPF is a diagnosis associated with high mortality. There was no observed increasing survival trend for patients with IPF before year 2010, with then a switch to an improvement, which is probably multifactorial.