Disparities in pulmonary fibrosis care in the United States: an analysis from the Nationwide Inpatient Sample

Current Landscape and Future Directions of Patient Education in Adults with Interstitial Lung Disease

Background

Understandable, comprehensive, and accessible educational materials for patients with interstitial lung disease (ILD) are lacking. Patients consistently ask for improved access to evidence-based information about ILD. Nonetheless, few research studies focus directly on developing and evaluating interventions to improve patient knowledge.

Objective

We describe the current landscape of patient education in ILD, identify gaps in current approaches to information delivery, and provide frameworks to address these challenges through novel educational tools.

Methods

A literature review was conducted in collaboration with a medical librarian (M.R.D.) in April 2022 using Ovid MEDLINE (1946-), Embase (1947-), Cochrane Central (1993-), and CINAHL (1961-). Search terms included "interstitial lung disease," "pulmonary fibrosis," "patient education," and "information seeking behavior" (see the data supplement for full search terms). Reference lists from selected articles were used to identify additional studies.

Results

Currently, patient education is commonly combined with exercise regimens in pulmonary rehabilitation programs in which benefits of the educational component alone are unclear. Few studies investigate improving knowledge access and acquisition for patients with ILD and their caregivers regarding self-management, oxygen use, and palliative care plans. Online distribution of health information through social media runs the risk of being unregulated and outdated, although it is an avenue of increasing accessibility.

Conclusion

By expanding access to novel ILD-specific education programs and accounting for social determinants of health that impact healthcare access, patient education has the potential to become more attainable, improving patient-centered outcomes. Further research into optimal development, delivery, and efficacy testing of patient education modalities in ILD is warranted.

Lung transplantation outcomes in patients from socioeconomically distressed communities

BACKGROUND

Previous studies have demonstrated racial and gender disparities in lung allocation, but contemporary data regarding socioeconomic disparities in post-transplant outcomes are lacking. We evaluated the impact of a composite socioeconomic disadvantage index on post-transplant outcomes.

METHODS

The Scientific Registry of Transplant Recipients identified 27,763 adult patients undergoing isolated primary lung transplantation between 2005 and 2020. Zip code-level socioeconomic distress was characterized using the Distressed Communities Index (DCI: 0-no distress, 100-severe distress) based on education level, poverty, unemployment, housing vacancies, median income, and business growth, and patients were stratified into high (DCI ≥60) or low (DCI <60) distressed groups.

RESULTS

Recipients from high-distress communities (n = 8006, 28.8%) were younger (59years [interquartile range {IQR} 50-64] vs 61years [IQR 52-66]), less often white (73 vs 85%), less likely to have a college degree (45 vs 59%), and more likely to have public insurance (57 vs 49%, all p < 0.001) compared to those from low-distress communities. Additionally, high-distress recipients were more likely to have group A diagnoses (32 vs 27%) and undergo bilateral lung transplants (72.4 vs 69.3%, all p < 0.001). Post-transplant survival at 5years was 55.7% (95% confidence interval [CI]: 54.4-56.9) in high-distress recipients and 58.2% (95% CI: 57.4-58.9) in low-distress recipients (p = 0.003). After adjustment, high distress level was independently associated with an increased risk of 5-year mortality (hazard ratio:1.09, 95% CI:1.04-1.15).

CONCLUSIONS

Recipients from distressed communities are at increased mortality risk following lung transplantation. Efforts should be focused on increased resource allocation and further study to better understand factors which may mitigate this disparity.

Supplemental Oxygen Therapy in Interstitial Lung Disease: A Narrative Review

Patients with interstitial lung diseases (ILD) often have hypoxemia at rest and/or with exertion, for which supplemental oxygen is commonly prescribed. The number of patients with ILD who require supplemental oxygen is unknown, although estimates suggest it could be as much as 40%; many of these patients may require high-flow support (>4 L/min). Despite its frequent use, there is limited evidence for the impact of supplemental oxygen on clinical outcomes in ILD, with recommendations for its use primarily based on older studies in patients with chronic obstructive pulmonary disease. Oxygen use in ILD is rarely included as an outcome in clinical trials. Available evidence suggests that supplemental oxygen in ILD may improve quality of life and some exercise parameters in patients whose hypoxemia is a limiting factor; however, oxygen therapy also places new burdens and barriers on some patients that may counter its beneficial effects. The cost of supplemental oxygen in ILD is also unknown but likely represents a significant portion of overall healthcare costs in these patients. Current Centers for Medicare and Medicaid reimbursement policies provide only a modest increase in payment for high oxygen flows, which may negatively impact access to oxygen services and equipment for some patients with ILD. Future studies should examine clinical and quality-of-life outcomes for oxygen use in ILD. In the meantime, given the current limited evidence for supplemental oxygen and considering cost factors and other barriers, providers should take a patient-focused approach when considering supplemental oxygen prescriptions in patients with ILD.

Interstitial Lung Disease and Sarcoidosis

Interstitial lung disease (ILD), a clinically recognized group of diseases resulting in pulmonary fibrosis, affects up to 200 individuals per 100,000 in the United States. Sarcoidosis has a wide range of clinical manifestations including pulmonary fibrosis. Health disparities are prevalent in both ILD and sarcoidosis around socioeconomic status, race, gender, and geographic location. This review outlines the known health disparities, discusses possible determinants of disparities, and outlines a path to achieve equity in ILD and sarcoidosis.

Barriers and facilitators to surgical access in underinsured and immigrant populations

BACKGROUND

Marginalized communities are at risk of receiving inequitable access to surgical care. We aimed to examine the barriers and facilitators to access to surgery in underinsured and immigrant populations.

METHODS

A systematic review of disparities in access to surgical care was performed between January 1, 2000-March 2, 2022. Methodological quality was assessed with the Mixed Methods Appraisal Tool. A convergent integrated approach was used to code common themes between studies.

RESULTS

Of 1315 publications, a total of 66 studies were included for systematic review. Eight studies specifically discussed immigrant patient populations. Barriers and facilitators to surgical access were categorized by patient and health systems related factors.

CONCLUSIONS

Established facilitators to improve surgical access are centered on patient-level factors while interventions to address systems-related barriers are limited and may be an area for further investigation. Research focused on access to surgery in immigrant populations remains sparse.

Disparities in Antifibrotic Medication Utilization Among Veterans With Idiopathic Pulmonary Fibrosis

BACKGROUND

Two antifibrotic medications, pirfenidone and nintedanib, are approved for the treatment of idiopathic pulmonary fibrosis (IPF). Little is known about their real-world adoption.

RESEARCH QUESTION

What are the real-world antifibrotic utilization rates and factors associated with uptake among a national cohort of veterans with IPF?

STUDY DESIGN AND METHODS

This study identified veterans with IPF who received care either provided by the Veterans Affairs (VA) Healthcare System or non-VA care paid for by the VA. Patients who had filled at least one antifibrotic prescription through the VA pharmacy or Medicare Part D between October 15, 2014, and December 31, 2019, were identified. Hierarchical logistic regression models were used to examine factors associated with antifibrotic uptake, accounting for comorbidities, facility clustering, and follow-up time. Fine-Gray models were used to evaluate antifibrotic use by demographic factors, accounting for the competing risk of death.

RESULTS

Among 14,792 veterans with IPF, 17% received antifibrotics. There were significant disparities in adoption, with lower uptake associated with female sex (adjusted OR, 0.41; 95% CI, 0.27-0.63; P < .001), Black race (adjusted OR, 0.60; 95% CI, 0.49-0.73; P < .001), and rural residence (adjusted OR, 0.88; 95% CI, 0.80-0.97; P = .012). Veterans who received their index diagnosis of IPF outside the VA were less likely to receive antifibrotic therapy (adjusted OR, 0.15; 95% CI, 0.10-0.22; P < .001).

INTERPRETATION

This study is the first to evaluate the real-world adoption of antifibrotic medications among veterans with IPF. Overall uptake was low, and there were significant disparities in use. Interventions to address these issues deserve further investigation.

Association of County-degree Social Vulnerability with Chronic Respiratory Disease Mortality in the United States

Rationale: Chronic respiratory diseases, the third leading cause of death worldwide, have been associated with significant morbidity, mortality, and increased economic burden that make a profound impact on individuals and communities. However, limited research has delineated complex relationships between specific sociodemographic disparities and chronic respiratory disease outcomes among U.S. counties. Objectives: To assess the association of county-level sociodemographic vulnerabilities with chronic respiratory disease mortality in the United States. Methods: Chronic respiratory disease mortality data among U.S. counties for 2014-2018 was obtained from the CDC WONDER (Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research) database. The social vulnerability index (SVI), including subindices of socioeconomic status, household composition and disability, minority status and language, and housing type and transportation, is a composite, percentile-based measure developed by the CDC to evaluate county-level sociodemographic vulnerabilities to disasters. We examined county-level sociodemographic characteristics from the SVI and classified the percentile rank into quartiles, with a higher quartile indicating greater vulnerability. The associations between chronic respiratory disease mortality and overall SVI, its four subindices, and each county characteristic were analyzed by negative binomial regression. Results: From 2014 to 2018, the age-adjusted mortality per 1,000,000 population attributed to chronic lower respiratory disease was 406.4 (95% confidence interval [CI], 405.5-407.3); chronic obstructive pulmonary disease (COPD), 393.7 (392.8-394.6); asthma, 10.0 (9.9-10.2); interstitial lung disease (ILD), 50.5 (50.1-50.8); idiopathic pulmonary fibrosis (IPF), 37.0 (36.7-37.3); and sarcoidosis, 5.3 (5.2-5.4). Counties in the higher quartile of overall SVI were significantly associated with greater disease mortality (chronic lower respiratory disease, incidence rate ratios: fourth vs. first quartile, 1.43 [95% CI, 1.39-1.48]; COPD, 1.44 [1.39-1.49]; asthma, 2.06 [1.71-2.48]; ILD, 1.07 [1.02-1.13]; IPF, 1.14 [1.06-1.22]; sarcoidosis, 2.01 [1.44-2.81]). In addition, higher mortality was also found in counties in the higher quartile of each subindex and most sociodemographic characteristics. Conclusions: Chronic respiratory disease mortalities were significantly associated with county-level sociodemographic determinants as measured by the SVI in the United States. These findings suggested sociodemographic determinants may add a considerable barrier to establishing health equity. Multidegree public health strategies and clinical interventions addressing inequitable outcomes of chronic respiratory disease should be developed and targeted in areas with greater social vulnerability and disadvantage.

Disparities in Lung Transplant among Patients with Idiopathic Pulmonary Fibrosis: An Analysis of the IPF-PRO Registry

Rationale: Lung transplant offers the potential to extend life for patients with idiopathic pulmonary fibrosis (IPF); yet, this therapeutic modality is only available to a small proportion of patients. Objectives: To identify clinical characteristics and social determinants of health that differentially associate with lung transplant compared with death in patients with IPF. Methods: We evaluated data from the Idiopathic Pulmonary Fibrosis Prospective Outcomes (IPF-PRO) Registry, a multicenter U.S. registry of patients with IPF that was diagnosed or confirmed at the enrolling center in the previous 6 months. Patients were enrolled between June 2014 and October 2018. Patients who were listed for lung transplant were not eligible to enroll in the registry, but patients could be listed for transplant after enrollment. We performed a multivariable time-to-event analysis incorporating competing risks methodology to examine differential associations between prespecified covariates and the risk of lung transplant versus death. Covariates included factors related to lung transplant eligibility, clinical characteristics of IPF, and social determinants of health. Covariates were modeled as time independent or time dependent as appropriate. Results: Among 955 patients with IPF, event rates of lung transplant and death were 7.4% and 16.3%, respectively, at 2 years. Covariates with the strongest differential association were age, median zip code income, and enrollment at a center with a lung transplant program. Lung transplant was less likely (hazard ratio [HR], 0.13 [95% confidence interval (CI), 0.06-0.28] per 5-yr increase) and death more likely (HR, 1.41 [95% CI, 1.22-1.64] per 5-yr increase) among those older than 70 years of age. Higher median zip code income was associated with lung transplant (HR, 1.22 [95% CI, 1.13-1.31] per $10,000 increase) but not death (HR, 0.99 [95% CI, 0.94-1.04] per $10,000 increase). Enrollment at a center with a lung transplant program was associated with lung transplant (HR, 4.31 [95% CI, 1.76-10.54]) but not death (HR, 0.99 [95% CI, 0.69-1.43]). Oxygen use with activity was associated with both lung transplant and death, but more strongly with lung transplant. A higher number of comorbidities was associated with an increased likelihood of death but not lung transplant. Conclusions: For patients in the Idiopathic Pulmonary Fibrosis Prospective Outcomes Registry, median zip code income and access to a lung transplant center differentially impact the risk of lung transplant compared with death, regardless of disease severity measures or other transplant eligibility factors. Interventions are needed to mitigate inequalities in lung transplantation based on socioeconomic status. Clinical trial registered with www.clinicaltrials.gov (NCT01915511).

Relative environmental and social disadvantage in patients with idiopathic pulmonary fibrosis

BACKGROUND

Air pollution exposure is associated with disease severity, progression and mortality in patients with idiopathic pulmonary fibrosis (IPF). Combined impacts of environmental and socioeconomic factors on outcomes in patients with IPF are unknown. The objectives of this study were to characterise the relationships between relative environmental and social disadvantage with clinical outcomes in patients with IPF.

METHODS

Patients with IPF were identified from a longitudinal database at University of California, San Francisco. Residential addresses were geocoded and linked to the CalEnviroScreen 3.0 (CES), a tool that quantifies environmental burden in California communities, combining population, environmental and pollution vulnerability into individual and composite scores (higher scores indicating greater disadvantage). Unadjusted and adjusted linear and logistic regression and Fine and Gray proportional hazards models were used.

RESULTS

603 patients were included. Higher CES was associated with lower baseline forced vital capacity (β=-0.073, 95% CI -0.13 to -0.02; p=0.006) and diffusion capacity of the lung for carbon monoxide (β=-0.11, 95% CI -0.16 to -0.06; p<0.001). Patients in the highest population vulnerability quartile were less likely to be on antifibrotic therapy (OR=0.33; 95% CI 0.18 to 0.60; p=0.001) at time of enrolment, compared with those in the lowest quartile. An association between CES and mortality was suggested, but sensitivity analyses demonstrated inconsistent results. Relative disadvantage of the study cohort appeared lower compared with the general population.

CONCLUSIONS

Higher environmental exposures and vulnerability were associated with lower baseline lung function and lower antifibrotic use, suggesting that relative socioenvironmental disadvantage has meaningful impacts on patients with IPF.

Neighborhood-level Disadvantage Impacts on Patients with Fibrotic Interstitial Lung Disease

RATIONALE

Fibrotic interstitial lung diseases (fILDs) represent a group of pathologic entities characterized by scarring of the lungs and high morbidity and mortality. Research investigating how socioeconomic and residential factors impact outcomes in patients with fILDs is lacking.

OBJECTIVES

To determine the association between neighborhood-level disadvantage and presentation severity, disease progression, lung transplant, and mortality in patients with fILD from the United States (U.S.) and Canada.

METHODS

Multi-center, international, prospective cohort study of 4729 patients with fILD from one U.S. and eight Canadian ILD registry sites. Neighborhood-level disadvantage was measured by the area deprivation index (ADI) in the U.S. and the Canadian Index of Multiple Deprivation (CIMD) in Canada.

MEASUREMENTS AND MAIN RESULTS

In the U.S., but not Canadian cohort, patients with fILD living in neighborhoods with the greatest disadvantage (top quartile) experience the highest risk of mortality (hazard ratio=1.51, p=0.002) and in subgroups of patients with idiopathic pulmonary fibrosis (IPF), the top quartile of disadvantage experienced the lowest odds of lung transplant (odds ratio=0.46, p=0.04). Greater disadvantage was associated with reduced baseline diffusion capacity for carbon monoxide (DLCO) in both cohorts, but it was not associated with baseline forced vital capacity (FVC) or FVC or DLCO decline in either cohort.

CONCLUSIONS

Patients with fILD who live in areas with greater neighborhood-level disadvantage in the U.S. experience higher mortality, and patients with IPF experience lower odds of lung transplant. These disparities are not seen in Canadian patients, which may indicate differences in access to care between the U.S. and Canada.

Social Disparities in Benign Lung Diseases

The many socioeconomic disparities in the myriad of diagnoses that make up benign lung diseases are unfortunately a global issue that was most recently highlighted by the COVID-19 pandemic of 2020. In this chapter, we will be reviewing the socioeconomic disparities in benign lung disease from both a United States perspective as well as a global perspective. We will cover the spectrum of infectious, obstructive, and restrictive lung disease and review the evidence on how social disparities affect these populations and their access to medical care.

Low income and outcome in idiopathic pulmonary fibrosis: An association to uncover

BACKGROUND

Low income, a known prognostic indicator of various chronic respiratory diseases, has not been properly studied in idiopathic pulmonary fibrosis (IPF). We hypothesize that a low income has an adverse prognostic impact on IPF.

METHODS

Patients were selected from the French national prospective cohort COFI. Patients' income was assessed through the median city-level income provided by the French National Institute of Statistics and Economic Studies according to their residential address. Patients were classified in two groups as "low income" vs. "higher income" depending on whether their annual income was estimated to be < or ≥18 170 €/year (the first quartile of the income distribution in the study population). The survival and progression-free survival (PFS) of the groups were compared by a log-rank test and a Cox model in multivariate analysis.

RESULTS

200 patients were included. The average follow-up was 33.8 ± 22.7 months. Patients in the low income group were significantly more likely to be of non-European origin (p < 0.006), and to have at least one occupational exposure (p < 0.0001), and they tended to have a higher cumulative exposure to fine particles PM_2.5 (p = 0.057). After adjusting for age, gender, forced vital capacity at inclusion, geographical origin, and occupational exposure having a low-income level was a factor associated with a worse PFS (HR: 1.81; CI_95%: 1.24-2.62, p = 0.001) and overall survival (HR: 1.49; CI_95%: 1.0006-2.23, p = 0.049).

CONCLUSIONS

Low income appears to be a prognostic factor in IPF. IPF patients with low incomes may also be exposed more frequently to occupational exposures.