Economic burden of incident interstitial lung disease (ILD) and the impact of comorbidity on costs of care

Cardiovascular disease in connective tissue disease-associated interstitial lung disease: A systematic review and meta-analysis of observational studies

OBJECTIVES

We performed a systematic review and meta-analysis to assess whether patients with connective tissue disease (CTD)-associated interstitial lung diseases (ILD) have an increased prevalence of cardiovascular (CV) disease and to validate associated risk factors.

METHODS

The PRISMA guidelines and PICO model were followed. We searched PubMed, Embase, Cochrane Library databases, Scopus, and Directory of Open Access Journals from inception to April 2024.

RESULTS

Thirteen studies comprising of 12,520 patients were included. Patients with CTD-ILD had a significantly increased risk of CV disease than patients with CTD (relative risk [RR] = 1.65, 95 % confidence interval [CI]: 1.41, 1.93), which are related to the proportion of men (P = 0.001) and the proportion of smokers (P = 0.045). Subgroup analysis found that patients with CTD-ILD had a higher risk of heart failure (RR = 2.84, 95 % CI: 1.50, 5.39), arrhythmia (RR = 1.55, 95 % CI: 1.22, 1.97) than patients with CTD. Another subgroup analysis showed that RA-ILD and SSc-ILD were associated with an increased risk of CV disease, but not IIM-ILD and MCTD-ILD (RA-ILD: RR = 2.19, 95 % CI: 1.27, 3.80; SSc-ILD: RR = 1.53, 95 % CI: 1.29, 1.82). Besides, patients with CTD-ILD had a higher prevalence of pulmonary arterial hypertension (RR = 2.48, 95 % CI: 1.69, 3.63) than patients with CTD.

CONCLUSIONS

Patients with CTD-ILD had a 1.65 times increased risk of CV than patients with CTD-non-ILD, with increased prevalence of heart failure and arrhythmia. The risk of CV disease in SSc-ILD and RA-ILD is increased and we should pay more attention to male smokers. In addition, compared with CTD patients, CTD-ILD patients had a higher risk of pulmonary arterial hypertension.

Sarcoidosis-Associated Pulmonary Hypertension

Sarcoidosis-associated pulmonary hypertension (SAPH) is a very severe complication of the disease, largely impacting its morbidity and being one of its strongest predictors of mortality. With the recent modifications of the hemodynamic definition of pulmonary hypertension (mean arterial pulmonary pressure >20 instead of <25 mmHg,) its prevalence is presently not precisely known, but it affects from 3 to 20% of sarcoid patients; mostly, although not exclusively, those with an advanced, fibrotic pulmonary disease. Its gold-standard diagnostic tool remains right heart catheterization (RHC). The decision to perform it relies on an expert decision after a non-invasive work-up, in which echocardiography remains the screening tool of choice. The mechanisms underlying SAPH, very often entangled, are crucial to define, as appropriate and personalized therapeutic strategies will aim at targeting the most significant ones. There are no recommendations so far as to the indications and modalities of the medical treatment of SAPH, which is based upon the opinion of a multidisciplinary team of sarcoidosis, pulmonary hypertension and sometimes lung transplant experts.

Interstitial lung disease hospitalizations, outcomes, and costs in the United States from 2008 to 2018

BACKGROUND

Interstitial lung diseases (ILD) are associated with frequent hospitalizations, however, limited studies have evaluated the hospitalization rates and outcomes.

STUDY DESIGN AND METHODS

We extracted hospitalization data for ILD patients using the National Inpatient Sample Database. Regression models were used to assess trends in hospitalizations and outcomes.

RESULTS

There were 345,063 hospitalizations with a principal diagnosis of ILD from 2008 to 2018. Hospitalization rates were higher in females, older age groups, and those living in rural areas. Rates were lower in those with income levels at or above the median and in the western U.S. Of those hospitalized, 5.1 % died, and ∼37 % required skilled nursing facility/home health. Deaths were lower among females and in those with Medicaid and private insurance. Rates were higher in the older age groups, those with median and above income levels, and those living in medium/small metro and rural areas. The overall hospitalization rate decreased by ∼23 % during this period. The percentage of deaths remained stable (except in rural hospitals) during this period. The average length of stay (LOS) was 5.5 days. The average hospital cost was $10,438 which increased by ∼38 %.

INTERPRETATION

Hospitalizations for ILD have been decreasing, however, the death percentage has been stable. The LOS has remained stable, but hospital costs have been increasing. We identified differences in ILD hospitalization rates and outcomes/costs based on patient and hospital characteristics. Identifying the causes for these differences would be important in reducing health disparities in ILD patients.

CLINICAL TRIAL REGISTRATION

n/a.

A systematic review on the economic burden of interstitial lung disease and the cost-effectiveness of current therapies

Background

The economic burden of interstitial lung disease (ILD) is unknown, limiting informed resource allocation and planning. We sought to conduct the first systematic review on the direct, indirect, and overall costs associated with ILD and to evaluate the cost-effectiveness of current therapies globally.

Methods

We conducted systematic reviews of ILD disease cost studies and cost-effectiveness analyses (CEAs) using MEDLINE, Embase, and Web of Science databases between 2000 and 2020. We compared ILD costs between countries according to the share of costs towards each country’s respective gross domestic product (GDP) per capita. Costs are reported in 2020 USD.

Results

We identified 25 disease cost studies and 7 CEAs. The direct medical costs ranged between $1824 and $116,927 annually per patient (median $32,834; 14–180% of GDP per capita in Western countries). The leading drivers of direct costs were inpatient (55%), outpatient (22%), and medication costs (18%), based on pooled estimates. Annual indirect costs ranged from $7149 to $10,902 per employed patient (median $9607; 12–23% of GDP per capita). Among the 7 CEAs, only 1 study (14%) showed an ILD therapy (ambulatory oxygen) was cost-effective compared to best supportive care.

Conclusion

The direct and indirect costs associated with ILD are consistently high in all countries with available data, with cost-effectiveness profiles of new therapies generally undesirable. Globally, the median total direct cost for ILD equates to 51% of a country’s GDP per capita and has been increasing over time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01922-2.

Identifying Patients with Group 3 Pulmonary Hypertension Associated with COPD or ILD Using an Administrative Claims Database

BACKGROUND

Group 3 pulmonary hypertension (PH) describes a subpopulation of patients with PH due to chronic lung disease and/or hypoxia, with chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) being two large subgroups. Claims database studies provide insights into the real-world treatment patterns and outcomes among these patients. However, claims data do not provide sufficient detail to assign the clinical subtype of PH required for identifying these patients.

METHODS

A panel of PH clinical experts and researchers was convened to discuss methodologies to identify patients with Group 3 PH associated with COPD or ILD in retrospective claims databases. To inform the discussion, a literature review was conducted to identify claims-based studies of Group 3 PH associated with COPD or ILD published from 2010 through June 2020.

RESULTS

Targeted title and abstract review identified 11 claims-based studies and two conference abstracts (eight based in the United States [US] and five conducted outside the US) that met search criteria. Based on insights from the panel and literature review, the following components were detailed across studies in the identification of Group 3 PH associated with COPD and ILD: (a) COPD or ILD identification, (b) PH identification, (c) defining the sequence between COPD/ILD and PH, and (d) other PH Group and Group 3 PH exclusions.

CONCLUSION

This article provides recommended approaches and considerations for identifying and studying patients with Group 3 PH associated with COPD or ILD using administrative claims data that provide the foundation for future validation studies.

Epidemiology, healthcare utilization, and related costs among patients with IPF: results from a German claims database analysis

Background

Idiopathic pulmonary fibrosis (IPF) is a progressive form of fibrosing interstitial pneumonia with poor survival. This study provides insight into the epidemiology, cost, and disease course of IPF in Germany.

Methods

A cohort of incident patients with IPF (n = 1737) was identified from German claims data (2014–2019). Incidence and prevalence rates were calculated and adjusted for age differences compared with the overall German population. All-cause and IPF-related healthcare resource utilization as well as associated costs were evaluated per observed person-year (PY) following the initial IPF diagnosis. Finally, Kaplan–Meier analyses were performed to assess time from initial diagnosis to disease deterioration (using three proxy measures: non-elective hospitalization, IPF-related hospitalization, long-term oxygen therapy [LTOT]); antifibrotic therapy initiation; and all-cause death.

Results

The cumulative incidence of IPF was estimated at 10.7 per 100,000 individuals in 2016, 10.9 in 2017, 10.5 in 2018, and 9.6 in 2019. The point prevalence rates per 100,000 individuals for the respective years were 21.7, 23.5, 24.1, and 24.1. On average, ≥ 14 physician visits and nearly two hospitalizations per PY were observed after the initial IPF diagnosis. Of total all-cause direct costs (€15,721/PY), 55.7% (€8754/PY) were due to hospitalizations and 29.1% (€4572/PY) were due to medication. Medication accounted for 49.4% (€1470/PY) and hospitalizations for 34.8% (€1034/PY) of total IPF-related direct costs (€2973/PY). Within 2 years of the initial IPF diagnosis (23.6 months), 25% of patients died. Within 5 years of diagnosis, 53.1% of patients had initiated LTOT; only 11.6% were treated with antifibrotic agents. The median time from the initial diagnosis to the first non-elective hospitalization was 5.5 months.

Conclusion

The incidence and prevalence of IPF in Germany are at the higher end of the range reported in the literature. The main driver for all-cause cost was hospitalization. IPF-related costs were mainly driven by medication, with antifibrotic agents accounting for around one-third of the total medication costs even if not frequently prescribed. Most patients with IPF do not receive pharmacological treatment, highlighting the existing unmet medical need for effective and well-tolerated therapies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-01976-0.

Prevalence of Sarcoidosis-Associated Pulmonary Hypertension: A Systematic Review and Meta-Analysis

Background

Sarcoidosis-associated pulmonary hypertension (SAPH) is associated with poor prognosis, conferring up to a 10-fold increase in mortality in patients with sarcoidosis, but the actual prevalence of SAPH is unknown.

Methods

The PubMed, Embase, and Cochrane Library databases were systematically searched for epidemiological studies reporting the prevalence of SAPH up to July 2021. Two reviewers independently performed the study selection, data extraction, and quality assessment. Studies were pooled using random-effects meta-analysis.

Results

This meta-analysis included 25 high-quality studies from 12 countries, with a pooled sample of 632,368 patients with sarcoidosis. The prevalence of SAPH by transthoracic echocardiography in Europe, the United States and Asia was 18.8% [95% confidence interval (CI): 11.1–26.5%], 13.9% (95% CI: 5.4–22.4%) and 16.2% (95% CI: 7.1–25.4%) separately, and the overall pooled prevalence was 16.4% (95%CI: 12.2–20.5%). By right heart catheterization (RHC), the pooled prevalence of SAPH was 6.4% (95% CI: 3.6–9.1%) in general sarcoidosis population, and subgroup analyses showed that the prevalence of SAPH was 6.7% (95% CI: 2.4–11.0%) in Europe and 8.6% (95% CI: −4.1 to 21.3%) in the United States. Further, the prevalence of pre-capillary PH was 6.5% (95% CI: 2.9–10.2%). For the population with advanced sarcoidosis, the pooled prevalence of SAPH and pre-capillary PH by RHC was as high as 62.3% (95% CI: 46.9–77.6%) and 55.9% (95% CI: 20.1–91.7%), respectively. Finally, the pooled prevalence of SAPH in large databases with documented diagnoses (6.1%, 95% CI: 2.6–9.5%) was similar to that of RHC. Substantial heterogeneity across studies was observed for all analyses (I² > 80%, P < 0.001).

Conclusions

The sarcoidosis population has a relatively low burden of PH, mainly pre-capillary PH. However, as the disease progresses to advanced sarcoidosis, the prevalence of SAPH increases significantly.

The prevalence and burden of interstitial lung diseases in the USA

Interstitial lung diseases (ILDs) are a heterogeneous group of diseases (i.e. idiopathic interstitial pneumonias, autoimmune ILDs, environmental exposure-related ILDs, sarcoidosis) but share several common clinical and pathophysiological features [1, 2]. ILDs are associated with significant morbidity, mortality and increased financial burden [3, 4].

Interstitial lung diseases (ILDs) are a significant contributor to disability and deaths in the USA. The prevalence and deaths from ILDs have increased but when adjusted for age, have been stable since 2010. https://bit.ly/3IDlZrg

Cost drivers in the pharmacological treatment of interstitial lung disease

INTRODUCTION

Treatments of interstitial lung diseases (ILDs) mainly focus on disease stabilization and relief of symptoms by managing inflammation or suppressing fibrosis by (in part costly) drugs. To highlight economic burden of drug treatment in different ILD-subtypes we assessed cost trends and therewith-associated drivers.

METHODS

Using data from the German, observational HILDA study we estimated adjusted mean medication costs over 36-month intervals using one- and two-part Generalized Estimating Equation (GEE) regression models with a gamma distribution and log link. Next, we determined factors associated with costs.

RESULTS

In Idiopathic pulmonary fibrosis (IPF) mean per capita medication costs increased from €1442 before to €11,000€ at the end of study. In non-IPF subtypes, the increase took place at much lower level. Mean per capita ILD-specific medication costs at the end of the study ranged between €487 (other ILD) and €9142 (IPF). At baseline, higher FVC %predicted values were associated with lower medication costs in IPF (-9%) and sarcoidosis (-1%). During follow up higher comorbidity burden escalated costs in progressive fibrosing ILD (PF-ILD) (+52%), sarcoidosis (+60%) and other ILDs (+24%). The effect of disease duration was not uniform, with cost savings in PF-ILD (-8%) and sarcoidosis (-6%), but increased spending in IPF (+11%).

CONCLUSION

Pharmacological management of ILD, in particular of IPF imposes a substantial economic burden on the healthcare system. Strategies to reduce comorbidity burden and early treatment may reduce the impact of ILDs on the healthcare system.

Comparative analysis of the bronchoalveolar microbiome in Portuguese patients with different chronic lung disorders

The lung is inhabited by a diverse microbiome that originates from the oropharynx by a mechanism of micro-aspiration. Its bacterial biomass is usually low; however, this condition shifts in lung cancer (LC), chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD). These chronic lung disorders (CLD) may coexist in the same patient as comorbidities and share common risk factors, among which the microbiome is included. We characterized the microbiome of 106 bronchoalveolar lavages. Samples were initially subdivided into cancer and non-cancer and high-throughput sequenced for the 16S rRNA gene. Additionally, we used a cohort of 25 CLD patients where crossed comorbidities were excluded. Firmicutes, Proteobacteria and Bacteroidetes were the most prevalent phyla independently of the analyzed group. Streptococcus and Prevotella were associated with LC and Haemophilus was enhanced in COPD versus ILD. Although no significant discrepancies in microbial diversity were observed between cancer and non-cancer samples, statistical tests suggested a gradient across CLD where COPD and ILD displayed the highest and lowest alpha diversities, respectively. Moreover, COPD and ILD were separated in two clusters by the unweighted UniFrac distance (P value = 0.0068). Our results support the association of Streptoccocus and Prevotella with LC and of Haemophilus with COPD, and advocate for specific CLD signatures.

Providing Patient-Centered Care in Interstitial Lung Disease

There have been growing interest in and emphasis on health systems adopting a patient-centered care (PCC) approach, which focuses on providing care that is respectful and responsive to patient preferences, needs, and values. The features of PCC can fall into 3 domains: structure, process, and outcomes. These domains encompass the necessary infrastructure and culture required to facilitate respectful and compassionate care and patient engagement. This review discusses the features that characterize each of these PCC domains and how they can be applied specifically to clinical care and research within the field of interstitial lung disease.

Frailty in patients with interstitial lung disease

PURPOSE OF REVIEW

The incidence of age-related diseases such as interstitial lung disease (ILD) is rising, and the importance of multimorbidity and accumulation of health deficits in patients with chronic lung diseases is increasingly recognized. There are multiple relationships between aging and ILD on a demographic and a biological level. Frailty conceptualizes the decline of a patient's physiological reserves and complements the chronological and biological aspects of aging.

RECENT FINDINGS

Frailty affects more than 50% of patients with ILD, with respiratory impairment, accelerated biological aging, comorbidities, medication adverse effects, and social factors collectively playing important roles. Frailty is an independent risk factor for adverse health outcomes such as hospitalizations and early mortality, including before and after lung transplant. Given the multicomponent determinants of frailty, programs such as pulmonary rehabilitation are promising strategies for managing this complex issue.

SUMMARY

Frailty is a common risk factor for adverse outcomes in patients with ILD. The multiple pathways leading to frailty are not completely understood, and further studies are needed to determine the optimal tools for assessment and to develop strategies to prevent and counteract frailty in the aging ILD population.

Diagnostic and Therapeutic Applications of Extracellular Vesicles in Interstitial Lung Diseases

Interstitial lung diseases (ILDs) are chronic irreversible pulmonary conditions with significant morbidity and mortality. Diagnostic approaches to ILDs are complex and multifactorial. Effective therapeutic interventions are continuously investigated and explored with substantial progress, thanks to advances in basic understanding and translational efforts. Extracellular vesicles (EVs) offer a new paradigm in diagnosis and treatment. This leads to two significant implications: new disease biomarker discovery that enables reliable diagnosis and disease assessment and the development of regenerative medicine therapeutics that target fibroproliferative processes in diseased lung tissue. In this review, we discuss the current understanding of the role of diseased tissue-derived EVs in the development of interstitial lung diseases, the utility of these EVs as diagnostic and prognostic tools, and the existing therapeutic utility of EVs. Furthermore, we review the potential therapeutic application of EVs derived from various cellular sources.