Early Intervention, Targeted Strategies Needed to Improve Disparities, Survival in Patients With IPF

Two posters presented last week at the CHEST 2024 annual meeting in Boston, Massachusetts, aimed to improve outcomes among patients with idiopathic pulmonary fibrosis (IPF) by understanding underlying socioeconomic and clinical risk factors.

Two posters highlighted the importance of addressing socioeconomic disparities and identifying clinical predictors to improve outcomes and survival rates among patients with idiopathic pulmonary fibrosis (IPF). | Image Credit: jirsak - stock.adobe.com

Impact of Socioeconomic Disparities on Inpatient Outcomes in Patients With IPF

About 30,000 to 40,000 new IPF cases are diagnosed annually, and as of 2022, nearly 100,000 Americans are living with the disease.¹ Consequently, the first poster analyzed how inpatient admissions of patients with IPF are divided by median income and insurance; it also explored pneumonia and respiratory failure rates within the population.

Through a retrospective cohort analysis of the 2020 National Inpatient Sample (NIS) database, the researchers grouped all adult patients with IPF according to the estimated median household income quartiles (EMHIQ) of residents in the patient’s ZIP code. Quartiles Q1 through Q4 contained patients with an EMHIQ of less than $50,000, $50,000 to $65,000, $65,000 to $85,000, and above $85,000, respectively.

The researchers also compared the expected primary payer (EPP), or insurance type, and rates of respiratory failure, mortality, and pneumonia across the different quartile groups. Within the database, they identified 5440 patients with IPF, with a mean (SD) age of 73.4 (10.8) years. The median length of stay (LOS) of those admitted with IPF was 5 days (IQR, 3-9).

When grouped by EMHIQ, 24.2%, 27.6%, 24.5%, and 23.7% of patients were distributed in the Q1, Q2, Q3, and Q4 groups, respectively. As for EPP, 78.3% of patients had Medicare, 13% had private insurance, and 5.4% had Medicare. The researchers determined that the EPP most prevalent in Q1 was Medicare (74.8%), followed by private insurance (12.8%) and Medicaid (7.8%). In comparison, a higher proportion of patients in Q4 had Medicare (81.4%) and private insurance (13.4%), while a lower amount had Medicaid (3.0%).

Additionally, when comparing pneumonia rates leading to acute exacerbations among the different quartile groups, they found an increased rate of pneumonia in Q1 when compared with Q4 (Q1, 29.4%; Q2, 28.2%; Q3, 25.8%; Q4, 24.9%). However, there were no significant differences in the rates of respiratory failure or mortality.

The researchers noted that these findings suggest a potential association between socioeconomic status and susceptibility to certain IPF complications. Consequently, they stated that addressing socioeconomic determinants is “imperative” for the timely identification of factors causing acute exacerbations of IPF, like pneumonia, and the implementation of early intervention strategies.

“Further research is warranted to explore the underlying mechanisms driving these disparities and to develop targeted interventions to reduce health inequities in the IPF population,” the authors concluded.

Predictors of Long-Term Survival in Patients With IPF

Building on the socioeconomic factors affecting IPF complications, the second poster took a clinical approach, using the IPF-PRO Registry to identify characteristics predictive of long-term survival in patients with IPF.² Patients diagnosed with IPF at the enrolling center within the past 6 months were included in the registry, which enrolled patients at 46 sites nationwide between June 2014 and October 2018.

Therefore, the researchers followed patients prospectively, with follow-up data collected until death, lung transplant, or withdrawal from the registry, for up to 5 years. Also, they used a Classification and Regression Tree (CART) to identify predictors of shorter (≤ 5 years) vs longer (> 5 years) survival following registry enrollment; the CART algorithm makes predictions based on relationships in the data. They considered the impact of various variables on survival, like age, IPF symptoms, and antifibrotic drug use.

The study population consisted of 819 patients, 278 of whom survived for more than 5 years after registry enrollment. The researchers identified the top 4 predictors that patients would survive more than 5 years: oxygen use, predicted forced vital capacity percentage (FVC %), body mass index (BMI), and age.

They noted that patients on oxygen had a 12% probability of surviving more than 5 years than those not on oxygen. However, a patient not on oxygen with a predicted FVC % of less than 65.2 had a 24% probability of surviving more than 5 years.

Overall, the researchers discovered that patients were more likely to survive beyond 5 years if they were younger than 81.5, not on oxygen, and had either an FVC % predicted of 76.6 or greater or an FVC % predicted between 65.2 and 76.6 combined with a BMI of 32.7 or higher. In these groups, 61% and 77% of patients, respectively, survived for more than 5 years.

Lastly, the optimism-corrected area under the curve (AUC) of the final CART was 0.73, with a 0.69 accuracy, indicating that it accurately predicted shorter vs longer survival in 69% of patients.

“Discussion with patients with IPF around prognosis should reflect that IPF has a variable course and that some patients will survive for more than 5 years,” the authors concluded. “Variables known at diagnosis can aid these decisions.”

Overall, both posters emphasize the importance of early identification and intervention in patients with IPF, highlighting how socioeconomic disparities affect complications and how clinical variables predict long-term survival. Consequently, the authors of both posters call for targeted strategies to improve patient outcomes.

References

1. Limon RR, Allu S, Allena N, Khaja M, Anto A. Unveiling the impact of socioeconomic status on hospitalization and complication in idiopathic pulmonary fibrosis. Poster presented at: CHEST Annual Meeting 2024; October 6-9, 2024; Boston, MA. doi:10.1016/j.chest.2024.06.1941
2. Kim HJ, Weber J, Neely ML, et al. Predicting long-term survival in patients with idiopathic pulmonary fibrosis: data from the IPF-PRO Registry. Poster presented at: CHEST Annual Meeting 2024; October 6-9, 2024; Boston, MA. doi:10.1016/j.chest.2024.06.1949