Treatment with two approved antifibrotics did not lessen a risk of death in recently hospitalized idiopathic pulmonary fibrosis (IPF) patients, but those using either therapy who went on to be discharged were more likely to live longer than those who were not, a database study reported.
“To our knowledge, this is the first use of real-world data to evaluate the impact of antifibrotics on hospitalization outcomes,” Andrew H. Limper, MD, a pulmonologist at the Mayo Clinic in Minnesota and the study’s senior author, said in a press release.
The study, “Outcomes for hospitalized patients with idiopathic pulmonary fibrosis treated with antifibrotic medications,” was published in BMC Pulmonary Medicine.
Antifibrotics, as the name suggests, are medications that can reduce fibrosis (scarring). Currently, two are approved to treat IPF patients in the U.S. : Esbriet (pirfenidone) and Ofev (nintedanib). Both were approved in 2014.
These medications were approved based on clinical trial data demonstrating they could slow lung function decline for IPF patients. However, the impact of these medications on mortality — both in general and in specific contexts — has not been throughly investigated.
A team led by Mayo scientists analyzed insurance data to better understand how antifibrotic treatment might affect mortality in IPF patients hospitalized for respiratory problems.
“A focus on acutely ill and hospitalized patients … has not been systematically studied since the availability of antifibrotic therapy,” they wrote.
Using insurance codes, researchers identified IPF patients who were hospitalized between 2015 and 2018, grouped as to whether or not they had been regularly filling prescriptions for Esbriet or Ofev prior to hospitalization. They then analyzed data using a method called propensity score matching — essentially, creating pairs of patients with similar demographic and clinical characteristics, but who differed based on whether or not they were taking an antifibrotic.
In all, 402 pairs of hospitalized IPF patients were score matched, as were 274 pairs of treated and untreated IPF patients who were admitted to an intensive care unit (ICU), as well as those who did or did not require mechanical ventilation while in the ICU.
Analyses showed that, at 30 days post-hospitalization, mortality rates were similar — about 10% — between IPF patients on antifibrotics and those who were not.
After two years, however, antifibrotic treatment prior to hospitalization was associated with a lower risk of all-cause mortality, by about 41%, than its non-use.
Subgroup analyses of the ICU pairs generally did not find statistically significant differences. But as these analyses were in smaller patient groups, they had less statistical power to detect significant results, the researchers noted. Nonetheless, “outcomes regarding those receiving ICU care appear more favorable than previously described” for people with IPF, they wrote.
Similar rates of ICU utilization across the groups also suggested antifibrotic treatment prior to hospitalization did not lessen the acuity of hospitalizations. However, if patients lived to be discharged, those with ongoing antifibrotic treatment had better survival rates for the two years they were followed.
“We observed no impact on 30-day mortality following respiratory-related hospitalizations for patients with IPF treated with antifibrotic medications, including those who required ICU care for any reason,” the researchers wrote. “However, if patients survived hospitalization, those with ongoing antifibrotic treatment had improved survival compared to their untreated counterparts up to two years.”
The team noted that antifibrotic treatment has been shown to lower the risk of events requiring hospitalization. They speculated that the reason for this is that, once patients are out of the hospital, antifibrotics use reduces the likelihood of a complication that requires a new hospital admission.
“Our findings are unique in that we tracked patients — with and without antifibrotics — after a hospitalization event, demonstrating the role antifibrotics have in improving survival for up to two years of therapy as well as in decreasing the number of hospitalizations,” said Limper, who is the associate dean and director of the Kern Center for the Science of Health Care Delivery at the Mayo Clinic.
“This study demonstrates the positive impact of these drugs for people with IPF. They are critical therapies to incorporate in the treatment of IPF,” said Bridget Burke, associate director for the Three Lakes Foundation, a nonprofit that helped to fund this study. Burke was not directly involved in the research.
Researchers noted their study could not distinguish between the two therapies in terms of benefits.
“We feel that analyzing differences between these medications to help guide clinicians in management and advances in therapy is of great interest and should be continued,” they added.