Proportion and predictors of FVC decline in patients with interstitial lung disease.

RATIONALE: The proportion of patients who develop progressive pulmonary fibrosis (PPF), along with risk factors for progression remain poorly understood. OBJECTIVES: To examine factors associated with an increased risk of developing PPF among patients at a referral center. METHODS: We identified patients with a diagnosis of interstitial lung disease (ILD) seen within the Cleveland Clinic Health System. Utilizing a retrospective observational approach we estimated the risk of developing progression by diagnosis group and identified key clinical predictors using the FVC component of both the original progressive fibrotic interstitial lung disease (PFILD) and the proposed PPF (ATS) criteria. RESULTS: We identified 5934 patients with a diagnosis of ILD. The cumulative incidence of progression over the 24 months was similar when assessed with the PFILD and PPF criteria (33.1 % and 37.9 % respectively). Of those who met the ATS criteria, 9.5 % did not meet the PFILD criteria. Conversely, 4.3 % of patients who met PFILD thresholds did not achieve the 5 % absolute FVC decline criteria. Significant differences in the rate of progression were seen based on underlying diagnosis. Steroid therapy (HR 1.46, CI 1.31-1.62) was associated with an increased risk of progressive fibrosis by both PFILD and PPF criteria. CONCLUSION: Regardless of the definition used, the cumulative incidence of progressive disease is high in patients with ILD in the 24 months following diagnosis. Some differences are seen in the risk of progression when assessed by PFILD and PPF criteria. Further work is needed to identify modifiable risk factors for the development of progressive fibrosis.

Association between nintedanib adherence trajectory and healthcare use among idiopathic pulmonary fibrosis patients.

BACKGROUND: Although inverse associations have been found between medication adherence and healthcare use and spending outcomes in many clinical settings, no studies to date have examined these relationships for patients with idiopathic pulmonary fibrosis (IPF) initiating nintedanib. We build on our prior study that used group-based trajectory modeling (GBTM) to compare inpatient hospitalization and medical care spending outcomes between groups of patients with different nintedanib adherence trajectories. METHODS: This analysis used 100% Medicare data and included beneficiaries with IPF who initiated nintedanib during 10/01/2014-12/31/2018. The sample consisted of community-dwelling older adults (≥ 66 years) with continuous coverage in Medicare Parts A (inpatient care), B (outpatient care) and D (prescription drugs) for one year before (baseline) and after (follow-up) initiating nintedanib. Patients were assigned to the GBTM-derived adherence trajectory group closest to their own nintedanib adherence experience. All-cause and IPF-related hospitalization events and total medical spending were measured during the follow-up period. Unadjusted and adjusted regression models were estimated to compare outcomes between patients in different nintedanib adherence trajectories. RESULTS: Among the 1,798 patients initiating nintedanib, the mean age was 75.4 years, 61.1% were male, and 91.1% were non-Hispanic white. The best-fitting GBTM had five adherence trajectories: high adherence, moderate adherence, high-then-poor adherence, delayed-poor adherence, and early-poor adherence. All-cause hospitalizations and total all-cause medical spending were higher among patients in the high-then-poor, delayed-poor and early-poor adherence trajectories than those in the high adherence trajectory. For example, adjusted total all-cause medical spending was $4,876 (95% CI: $1,470 to $8,282) higher in the high-then-poor adherence trajectory, $3,639 (95% CI: $1,322 to $5,955) higher in the delayed-poor adherence trajectory and $3,907 (95% CI: $1,658 to $6,156) higher in the early-poor adherence trajectory compared with the high adherence trajectory. IPF-related hospitalizations and medical care spending were higher among those in the high-then-poor adherence trajectory compared with those in the high adherence trajectory. CONCLUSIONS: Poor adherence to nintedanib was associated with all-cause hospitalizations and medical costs. Therefore, improved adherence programs, such as support programs, can be implemented to reduce economic burden.

Health care costs and utilization of progressive fibrosing lung disease by underlying interstitial lung disease type.

BACKGROUND: Fibrosing interstitial lung disease (ILD) encompasses more than 200 diverse pulmonary disorders, of which up to 40% become progressive. The 4 underlying ILD types most likely to result in progression are unclassified ILD/idiopathic interstitial pneumonia (IIP), autoimmune ILDs, exposure-related ILD/hypersensitivity pneumonitis, and sarcoidosis. OBJECTIVE: To compare health care resource utilization (HCRU) and costs among patients with fibrosing ILD that has progressed ("progressive" fibrosing cohort) vs patients whose fibrosis did not meet criteria set for progression ("not yet progressed" cohort). METHODS: This was a noninterventional study of commercial enrollees and Medicare Advantage with Part D beneficiaries, which used administrative claims data for the period from October 1, 2015, through May 31, 2021. Adult patients (aged ≥18 years) with fibrosing ILD and 12 months of continuous health plan enrollment were included. Patients with idiopathic pulmonary fibrosis, baseline ILD diagnoses, or missing demographic data were excluded. Patients were first classified according to the underlying type of fibrosing ILD. For statistical analyses of outcomes, 2 cohorts were compared within each subtype: progressive fibrosing ILD vs not yet progressed ILD. The final study population included propensity score-matched (PSM) patients (1:1) based on pre-ILD baseline demographic and clinical characteristics. HCRU categories included inpatient hospitalization counts and the number of inpatient days and total costs (in 2021 US dollars), analyzed descriptively and weighted by the per-patient-per-month cost. Lin's regression was used to predict 12-month total cost estimates for comparison by cohort. RESULTS: The distribution by underlying conditions was as follows: autoimmune ILD (n = 4,156), HP (n = 8,181), sarcoidosis (n = 775), and unclassified ILD/IIP (n = 18,635). After PSM, pre-ILD baseline variables were generally well balanced between the progressive and not yet progressed fibrosing ILD cohorts. For all underlying subtypes of ILD, patients in the progressive cohort had significantly more utilization and higher costs compared with patients in the not yet progressed cohort. Progressive cohorts had significantly higher adjusted rates of inpatient days among patients with at least 1 inpatient stay compared with the not yet progressed cohorts (all P < 0.01). In addition, the progressive cohorts had significantly higher adjusted 12-month total costs, with the differences ranging from $24,493 to $55,072 (all comparisons P < 0.001). CONCLUSIONS: Irrespective of underlying ILD type, patients with progressive fibrosing ILD had significantly increased HCRU and cost relative to those whose fibrosing ILD had not yet progressed.