Clarifying the diagnosis of post-inflammatory pulmonary fibrosis: a population-based study

Relation of Pulmonary Diffusing Capacity Decline to HRCT and VQ SPECT/CT Findings at Early Follow-Up after COVID-19: A Prospective Cohort Study (The SECURe Study)

A large proportion of patients exhibit persistently reduced pulmonary diffusion capacity after COVID-19. It is unknown whether this is due to a post-COVID restrictive lung disease and/or pulmonary vascular disease. The aim of the current study was to investigate the association between initial COVID-19 severity and haemoglobin-corrected diffusion capacity to carbon monoxide (DLco) reduction at follow-up. Furthermore, to analyse if DLco reduction could be linked to pulmonary fibrosis (PF) and/or thromboembolic disease within the first months after the illness, a total of 67 patients diagnosed with COVID-19 from March to December 2020 were included across three severity groups: 12 not admitted to hospital (Group I), 40 admitted to hospital without intensive care unit (ICU) admission (Group II), and 15 admitted to hospital with ICU admission (Group III). At first follow-up, 5 months post SARS-CoV-2 positive testing/4 months after discharge, lung function testing, including DLco, high-resolution CT chest scan (HRCT) and ventilation-perfusion (VQ) single photon emission computed tomography (SPECT)/CT were conducted. DLco was reduced in 42% of the patients; the prevalence and extent depended on the clinical severity group and was typically observed as part of a restrictive pattern with reduced total lung capacity. Reduced DLco was associated with the extent of ground-glass opacification and signs of PF on HRCT, but not with mismatched perfusion defects on VQ SPECT/CT. The severity-dependent decline in DLco observed early after COVID-19 appears to be caused by restrictive and not pulmonary vascular disease.

Evaluation for clinical benefit of metformin in patients with idiopathic pulmonary fibrosis and type 2 diabetes mellitus: a national claims-based cohort analysis

Background

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease with high morbidity and limited treatment options. Type 2 diabetes mellitus (T2DM) is a common comorbid illness among patients with IPF and is often treated with metformin, the first-line agent in the management of T2DM. There is growing evidence demonstrating metformin’s anti-fibrotic properties; however, there is little real-world clinical data regarding its potential effectiveness in IPF. This study aims to evaluate the clinical benefit of metformin in patients with IPF and T2DM.

Methods

This nationwide cohort study used de-identified administrative claims data from OptumLabs® Data Warehouse to identify 3599 adults with IPF and concomitant T2DM between January 1, 2014 and June 30, 2019. Two cohorts were created: a cohort treated with metformin (n = 1377) and a cohort not treated with metformin (n = 2222). A final 1:1 propensity score-matched cohort compared 1100 patients with IPF and T2DM receiving metformin to those with both diagnoses but not receiving metformin; matching accounted for age, sex, race/ethnicity, residence region, year, medications, oxygen use, smoking status, healthcare use, and comorbidities. Outcomes were all-cause mortality (primary) and hospitalizations (secondary).

Results

Among 2200 patients with IPF and T2DM included in this matched analysis, metformin therapy was associated with a reduction in all-cause mortality (hazard ratio [HR], 0.46; 95% confidence interval [CI], 0.36–0.58; p < 0.001) and hospitalizations (HR, 0.82; 95% CI, 0.72–0.93; p = 0.003) compared to patients not receiving metformin.

Conclusions

Among patients with IPF and T2DM, metformin therapy may be associated with improved clinical outcomes. However, further investigation with randomized clinical trials is necessary prior to metformin’s broad implementation in the clinical management of IPF.

Adoption of the Antifibrotic Medications Pirfenidone and Nintedanib for Patients with Idiopathic Pulmonary Fibrosis

Rationale: In October 2014, the antifibrotic medications pirfenidone and nintedanib became the first medications approved by the U.S. Food and Drug Administration for use in patients with idiopathic pulmonary fibrosis (IPF). Since approval, there has been no nonregistry analysis of the real-world adoption of these medications in everyday clinical practice. Objectives: To evaluate the adoption, persistence, and out-of-pocket (OOP) costs of pirfenidone and nintedanib since their approval in the United States in 2014. Methods: A retrospective cohort analysis was performed by identifying privately insured and Medicare Advantage beneficiaries with IPF. We then split the patients into three cohorts: those who were untreated and those who filled a prescription for either pirfenidone or nintedanib between October 1, 2014, and July 31, 2019. The primary outcome was adoption of the medications. Secondary outcomes included medication persistence and prescription drug costs. Results: A total of 10,996 patients with IPF were identified in the data set. A minority of patients (26.4%) with IPF identified in the cohort had started either medication since approval in 2014, with the adoption of both medications being comparable at around 13.2%. Those receiving the medications were younger (72 vs. 73.9 yr; P < 0.0001) and healthier (3.9 vs. 4.9 comorbidities; P < 0.0001) than those not receiving treatment. Men were significantly more likely to receive treatment than woman (30.0% vs. 21.9%; P < 0.0001). Among treated patients, 42.8% discontinued the medications during the study period. Patients' OOP expenses per month were high for both drugs (mean, $397.51 for nintedanib; mean, $394.49 for pirfenidone). Conclusions: The adoption of both the antifibrotic medications in the United States in everyday practice has been low since approval and may be associated with the high OOP cost.

Outcomes for hospitalized patients with idiopathic pulmonary fibrosis treated with antifibrotic medications

Background

Idiopathic Pulmonary Fibrosis is a chronic, progressive interstitial lung disease for which there is no cure. However, lung function decline, hospitalizations, and mortality may be reduced with the use of the antifibrotic medications, nintedanib and pirfenidone. Historical outcomes for hospitalized patients with Idiopathic Pulmonary Fibrosis are grim; however there is a paucity of data since the approval of nintedanib and pirfenidone for treatment. In this study, we aimed to determine the effect of nintedanib and pirfenidone on mortality following respiratory-related hospitalizations, intensive care unit (ICU) admission, and mechanical ventilation.

Methods

Using a large U.S. insurance database, we created a one-to-one propensity score matched cohort of patients with idiopathic pulmonary fibrosis treated and untreated with an antifibrotic who underwent respiratory-related hospitalization between January 1, 2015 and December 31, 2018. Mortality was evaluated at 30 days and end of follow-up (up to 2 years). Subgroup analyses were performed for all patients receiving treatment in an ICU and those receiving invasive and non-invasive mechanical ventilation during the index hospitalization.

Results

Antifibrotics were not observed to effect utilization of mechanical ventilation or ICU treatment during the index admission or effect mortality at 30-days. If patients survived hospitalization, mortality was reduced in the treated cohort compared to the untreated cohort when followed up to two years (20.1% vs 47.8%).

Conclusions

Treatment with antifibrotic medications does not appear to directly improve 30-day mortality during or after respiratory-related hospitalizations. Post-hospital discharge, however, ongoing antifibrotic treatment was associated with improved long-term survival.

In-hospital mortality trends among patients with idiopathic pulmonary fibrosis in the United States between 2013-2017: a comparison of academic and non-academic programs

Background

Idiopathic pulmonary fibrosis (IPF) is a devastating condition characterized by progressive lung function decline and early mortality. While early accurate diagnosis is essential for IPF treatment, data evaluating the impact of hospital academic status on IPF-related mortality remains limited. Here we examined in-hospital mortality trends for patients with IPF from 2013 to 2017. We hypothesized that in-hospital IPF mortality would be influenced by hospital academic setting.

Methods

Hospitalization data was extracted from the National Inpatient Sample (NIS) for subjects with an international classification of disease code for IPF. In-hospital mortality stratified by hospital setting (academic versus non-academic) was the primary outcome of interest, with secondary analyses performed for subgroups with and without respiratory failure and requiring mechanical ventilation. Predictors of mortality were then assessed.

Results

Among 93,680 patients with IPF requiring hospitalization, 58,450 (62.4%) were admitted to academic institutions. In-hospital mortality decreased significantly in those admitted to an academic hospital (p < 0.001) but remained unchanged in patients admitted to a non-academic hospital. A plateau in-hospital mortality was observed among all hospitalized patients (p = 0.12), with a significant decrease observed for patients with admitted respiratory failure (p < 0.001) and those placed on mechanic ventilation (p < 0.001).

Conclusion

In-hospital mortality decreased significantly for patients with IPF admitted to an academic hospital, suggesting that management strategies may differ by hospital setting. Mortality among those with respiratory failure and those requiring mechanical ventilation has dropped significantly. Our findings may underscore the importance of promoting early referral to an academic institution and adherence to international treatment guidelines.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-020-01328-y.

Impact of Idiopathic Pulmonary Fibrosis on Longitudinal Health-care Utilization in a Community-Based Cohort of Patients

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a rare, chronic lung disease associated with substantial symptom burden, morbidity, and cost. Delivery of high-quality effective care in IPF requires understanding health-care resource utilization (HRU) patterns; however, longitudinal data from real-world populations are limited.

RESEARCH QUESTION

This study aimed to define HRU attributable to IPF by evaluating a longitudinal cohort of community patients with IPF compared with matched control subjects.

STUDY DESIGN AND METHODS

Incident IPF cases were identified in the Kaiser Permanente Northern California electronic health records (2000-2015) using case-validated code-based algorithms. IPF cases were compared with matched control subjects by age, sex, and length of enrollment. Annual rates of HRU measures were assessed during the 5 years pre- and postdiagnosis. Poisson generalized estimating equations were used to estimate adjusted case-control differences in HRU. IPF treatment trends were assessed before and after the availability of IPF-specific medications.

RESULTS

A total of 691 IPF cases were identified and matched with 3,452 control subjects. Adjusted rates of all diagnostic procedures were significantly increased (P < .001) for IPF cases compared with control subjects in both the pre- and postindex periods, including chest CT scans (pre-relative risk [RR], 80.35; post-RR, 32.79), 6-min walk tests (pre-RR, 20.81; post-RR, 34.49), and pulmonary function tests (pre-RR, 9.50; post-RR, 13.24). All-cause hospitalizations (pre-RR, 1.42; post-RR, 2.33) and outpatient visits (pre-RR, 1.22; post-RR, 1.80) were significantly higher among cases compared with control subjects during both the preindex (P < .05) and postindex (P < .001) periods. We observed use of immunosuppressive and IPF-specific therapies prior to diagnosis, and high rates of corticosteroid use before and after diagnosis.

INTERPRETATION

This study defines a marked increase in HRU in patients with IPF compared with control subjects, with accelerated use beginning at least 1 year prediagnosis and elevated use sustained over the following 5 years. To our knowledge, this is the first study to evaluate longitudinal medication trends in IPF. Collectively, this information is foundational to advancing IPF care delivery models and supporting clinical decision-making.

Clinical Effectiveness of Antifibrotic Medications for Idiopathic Pulmonary Fibrosis

Rationale: Since their approval, there has been no real-world or randomized trial evidence evaluating the effect of the antifibrotic medications pirfenidone and nintedanib on clinically important outcomes such as mortality and hospitalizations. Objectives: To evaluate the clinical effectiveness of the antifibrotic medications pirfenidone and nintedanib in patients with idiopathic pulmonary fibrosis. Methods: Using a large U.S. insurance database, we identified 8,098 patients with idiopathic pulmonary fibrosis between October 1, 2014 and March 1, 2018. A one-to-one propensity score-matched cohort was created to compare patients treated with antifibrotic medications (n = 1,255) with those not on treatment (n = 1,255). The primary outcome was all-cause mortality. The secondary outcome was acute hospitalizations. Subgroup analyses were performed to evaluate mortality differences by drug. Measurements and Main Results: The use of antifibrotic medications was associated with a decreased risk of all-cause mortality (hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.62-0.98; P value = 0.034). However, this association was present only through the first 2 years of treatment. There was also a decrease in acute hospitalizations in the treated cohort (HR, 0.70; 95% CI, 0.61-0.80; P value <0.001). There was no significant difference in all-cause mortality between patients receiving pirfenidone and those on nintedanib (HR, 1.14; 95% CI, 0.79-1.65; P = 0.471). Conclusions: Among patients with idiopathic pulmonary fibrosis, antifibrotic agents may be associated with a lower risk of all-cause mortality and hospitalization compared with no treatment. Future research should test the hypothesis that these treatments reduce early, but not long-term, mortality as demonstrated in our study.