Smoking, Oxygen Use Linked to Higher Hospitalization Risk in IPF

While receiving treatment at specialized centers lowers the risk of hospitalization among patients with idiopathic pulmonary fibrosis (IPF), being a former smoker and requiring oxygen therapy are both associated with a higher likelihood of hospitalization.

These are some of the findings of multiple studies that Boehringer Ingelheim will present about the management of pulmonary fibrosis associated with interstitial lung disease (IPF-ILD) at the 2021 American Thoracic Society (ATS) International Conference, held online, May 14–19.

All these studies are analyses of data gathered in the idiopathic pulmonary fibrosis – PROspective Outcomes (IPF-PRO) Registry (NCT01915511), one of the largest IPF patient registries that has been created to further understand the natural progression of IPF and current treatment approaches.

IPF-PRO is a collaboration between Boehringer and the Duke Clinical Research Institute that is building on the knowledge collected from multiple clinical sites in the U.S.

“The depth and breadth of research findings from our interstitial lung disease program that we presented at this year’s ATS builds on our company’s legacy and commitment to respiratory medicine for the past 100 years,” Craig Conoscenti, MD, ILD program lead at Boehringer, said in a press release. 

There are around 200 different types of ILDs, all characterized by inflammation and scarring in the lungs that negatively affect lung function. IPF is the most common form of ILD and is both progressive and serious.

Boehringer recently shared highlights of selected registry analyses evaluating the management of IPF-ILD that will be featured across multiple abstracts at the conference.

One of the abstracts, titled “Exploring Relationships Between Resources and Practices of ILD Centers and Outcomes in Patients with Idiopathic Pulmonary Fibrosis: Data from the IPF-PRO Registry,” describes data from a survey that was sent to IPF-PRO recruiting centers to gather information on resources, operations, and self-assessment practices.

Data were provided by 27 centers, staffed mainly by physicians and nurses, but some also had pharmacists, social workers, or respiratory therapists. 

Results showed that patients receiving treatment at sites using an ILD-related quality improvement project had a lower risk of hospitalization. In contrast, patients who participated in routine remote monitoring had a higher risk of hospitalization. Quality improvement projects are initiatives to help improve patients’ care via best practices, with education for providers, patients, and caregivers.

Another abstract, titled “Implementation of Guideline Recommendations and Outcomes in Patients with Idiopathic Pulmonary Fibrosis: Data from the IPF-PRO Registry,” focuses on investigating the extent to which international guidelines for the management of IPF have been implemented at referral centers, and explores possible associations between their implementation and patients’ clinical outcomes. 

The implementation of eight recommendations in clinical practice guidelines was assessed within the six months after registry enrollment, including visits to specialized clinics, lung function tests, use of oxygen in those with low oxygen, referral for pulmonary rehabilitation, treatment of reflux disease, initiation of anti-fibrotic therapy, and referral for lung transplant evaluation.

The analysis revealed that 6.3% of IPF patients across the registry, primarily those with more severe disease, received all the recommended services and treatments they were eligible for. However, after adjusting for disease severity, no association was found between the implementation of these guidelines and clinical outcomes.

Another abstract, titled “Characteristics of Patients with Idiopathic Pulmonary Fibrosis Admitted to Hospital: Data from the IPF-PRO Registry,” describes data from an analysis that evaluated the characteristics of IPF patients who were hospitalized and those who were not during follow-up, with data collected approximately every six months. 

During a maximum follow-up of 67 months (about 5.5 years), 550 out of 1,001 patients (54.9%) were hospitalized. In nearly half of the cases (45.5%), the first hospitalization was due to respiratory issues. Most patients (74.5%) who were admitted to the hospital had one (52.5%) or two (22.0%) hospitalizations during follow-up. 

Compared to non-hospitalized patients, those who were hospitalized were more likely to be former smokers (69.3% vs. 59.9%), require oxygen therapy at rest (22.4% vs. 16.9%), and while performing activities (38.5% vs. 29.3%). However, lung function was similar in participants in both groups.

Another abstract, titled “Disparities in Lung Transplantation Among Patients with Idiopathic Pulmonary Fibrosis: Data from the IPF-PRO Registry,” describes data from a study that identified clinical and socioeconomic characteristics that predicted lung transplant compared with mortality. 

Assessed factors included lung transplant eligibility (age, body-fat content, smoking status), clinical characteristics (sex, evidence of fibrosis, disease severity, quality of life, co-existing conditions, respiratory hospitalizations), as well as socioeconomic factors (distance to enrolling center, lung transplant patients at enrolling center, median household income, type of health insurance).

The event rate was 7.4% for lung transplant and 16.3% for death among 955 IPF patients after two years. Those older than 70 with a high number of co-existing conditions had a significantly greater risk of death versus transplant. 

In contrast, a greater risk of lung transplant versus death was seen in patients who had a higher median household income, who enrolled at a center that conducted more than 30 transplants per year, and had prior respiratory hospitalizations. Oxygen use with activity was linked more strongly with lung transplant, and worse lung function was associated with both lung transplant and death.

Socioeconomic factors impacted the risk of lung transplant compared with death differently, regardless of disease severity or transplant eligibility factors. “Additional interventions are needed to mitigate inequalities based on socioeconomic status,” the authors wrote. 

Finally, another abstract, titled “Post-Hospitalization Mortality in Patients with Idiopathic Pulmonary Fibrosis: Data from the IPF-PRO Registry,” describes findings from a study that examined the association between hospitalization and mortality during hospitalization or within 90, 180, and 360 days of discharge. 

Over a follow-up of 67.0 months (over 5.5 years), a total of 550 patients (54.9%) were hospitalized. During follow-up, deaths occurred in 28.5% of patients who were hospitalized at least once, and in 38.2% of those who were admitted to the hospital at least once due to respiratory issues.

Researchers found significant associations between all-cause hospitalization and respiratory-related hospitalization and the risk of mortality within 90, 180, and 360 days of discharge. There was a greater risk of mortality following hospitalization for respiratory-related issues compared to non-respiratory reasons.

“Hospitalizations are common among patients with IPF and are associated with a high risk of mortality in the year following discharge, particularly among patients hospitalized for a respiratory-related cause,” the authors wrote. 

Conoscenti added: “The IPF-PRO Registry continues to provide critical insights into the current management of IPF patients that will help clinicians improve the care of people living with this disease.”