ABSTRACT In 567 PH‐COPD patients from the PVRI GoDeep Meta‐Registry, ACE inhibitor use was associated with improved survival only in severe PH (PVR > 5 WU), supporting prospective trials targeting this high‐risk subgroup.
The Importance of Liver‐Lung Communication in Pulmonary Vascular Diseases
ABSTRACT In normal health, the liver and lungs enjoy a close anatomic, physiologic, and functional relationship. In the context of pulmonary vascular disease, however, there is accumulating evidence that the interplay between the gut microbiome, hepatic system, and pulmonary vasculature (so‐called “gut‐liver‐lung” axis) plays an important role in driving disease pathogenesis and determining clinical outcomes. Despite recognizing the importance of the gut‐liver‐lung axis in pulmonary vascular disease however, little is known about the clinical characteristics, circulating factors, and physiologic pathways that mediate this important axis of communication. In this clinical and translationally focused review, we provide an overview of liver‐lung communication in normal physiology, and contrast this with gut‐liver‐lung derangements in pulmonary arterial hypertension, portopulmonary hypertension, and hepatopulmonary syndrome. We conclude with identifying key gaps in knowledge that will need to be addressed in order to manipulate the gut‐liver‐lung axis to prevent worsening pulmonary vascular disease, develop novel therapeutics, and improve patient outcomes.
Hemodynamics and Phosphodiesterase-5 Inhibitor Treatment Associated with Survival in Pulmonary Hypertension in Interstitial Lung Disease: A PVRI GoDeep Meta-Registry Analysis
Abstract Rationale Pulmonary hypertension (PH) in interstitial lung disease (ILD) lacks approved therapies. Objectives The Pulmonary Vascular Research Institute GoDeep metaregistry collects real-world data of patients with PH from international PH referral centers. Methods Patients with ILD-PH and relevant subgroups (idiopathic interstitial pneumonia [IIP], idiopathic pulmonary fibrosis [IPF]) were stratified by pulmonary vascular resistance (PVR). Kaplan-Meier survival analyses and adjusted Cox proportional hazards models were employed, additionally accounting for immortal time bias, sensitivity analyses, Heller explained relative risk statistics, and target trial emulation framework analysis. Measurements and Main Results Among 34,482 patients, 940 with hemodynamically fully characterized incident ILD-PH (median age, 67 [IQR, 59–74] yr) were identified. A total of 62% had severe ILD-PH with PVR >5 Wood units (WU) and poor survival rates (29% and 18% at 3 and 5 yr), significantly worse than patients with ILD-PH with PVR ≤5 WU and patients with pulmonary arterial hypertension. Survival was poorest in severe IPF-PH. A total of 59% of all patients ILD-PH received PH-targeted therapy, predominantly phosphodiesterase-5 inhibitors (PDE5is). PDE5i treatment was consistently associated with significantly improved survival in patients with severe PH (hazard ratios of 0.537 [0.370–0.781], 0.461 [0.233–0.913], and 0.435 [0.215–0.8] for IIP-PH, IPF-PH, and IIP-PH with nintedanib/pirfenidone background therapy), but not in patients with less severe hemodynamic impairment, supported by sensitivity analyses, Heller statistics, and target trial emulation framework analysis. The survival statistics of patients with PDE5i-treated IIP-PH or IPF-PH were validated in the independent COMPERA registry. Combination therapy with PDE5is and inhaled prostacyclin analogues was superior to monotherapy using PDE5is (hazard ratio, 0.341; 0.205–0.566). Conclusions Prognosis in ILD-PH was generally very poor and was related to PH severity. PDE5i treatment in severe IIP-PH and IPF-PH was associated with improved survival, which is to be further verified in controlled trials.
Survival Outcomes and Impact of Targeted PAH Therapy in Portopulmonary Hypertension in the PVRI GoDeep Meta‐Registry
ABSTRACTPortopulmonary hypertension (PoPH), a type of pulmonary arterial hypertension (PAH) in patients with liver disease, is associated with high morbidity and mortality. The relationship between cardiopulmonary hemodynamics, PAH therapy, and survival in PoPH remains unclear. We performed a retrospective cohort study of PoPH patients from the international pulmonary hypertension (PH) meta‐registry, PVRI GoDeep. PAH was defined by a mean pulmonary arterial pressure > 20 mmHg, pulmonary arterial wedge pressure ≤ 15 mmHg, and a pulmonary vascular resistance (PVR) > 2 Wood Units. PoPH diagnoses were assigned by each center's PH specialist based on international guidelines at the time of enrollment. 246 incident PoPH patients met eligibility criteria and were included in the analysis, equally split between males (51%) and females (49%), with a median age of 54 years. When compared to both patients with IPAH and those with other subtypes of PAH (not classified as PoPH or IPAH), those with PoPH had significantly lower 5‐year survival rates (46% vs. 68% vs. 65%, log‐rank p < 0.001). Amongst the PoPH patients, however, there was no significant difference in 5‐year survival when dichotomized by disease severity, either by a PVR of 5 Wood Units or a CI of 2.5 L/min/m2. Treatment of the PoPH patients with PAH‐targeted therapies was associated with significantly higher 5‐year survival rates compared to those not receiving such treatments, as shown by Kaplan–Meier analysis. This survival benefit was observed for PDE5i (50% vs. 34%, log‐rank p = 0.029), ERA (58% vs. 34%, log‐rank p < 0.001), and the combination of PDE5i and/or ERA (51% vs. 22%, log‐rank p < 0.001), as well as any PAH‐targeting treatment (50% vs. 26%, log‐rank p = 0.007). Corresponding survival advantage was noted when including only PoPH patients with MELD Score ≥ 13. PoPH is a disease with significantly worse long‐term survival than other PAH subtypes, but targeted PAH therapy is associated with a robust survival benefit. Survival did not differ across high‐risk PVR and cardiac index thresholds, suggesting the factors that influence prognosis and survival in PoPH may be unique as compared to other PAH subtypes, and warrant further investigation.
Medication Nonadherence in Patients with Pulmonary Arterial Hypertension: The Pulmonary Hypertension Association Registry (PHAR)
Abstract Rationale Pulmonary arterial hypertension (PAH) is associated with significant morbidity and mortality. The extent of medication nonadherence in PAH is uncertain and may be linked to adverse outcomes. There has been a lack of multicenter, registry-based studies assessing medication nonadherence and patient-centered outcomes in PAH. Objectives To determine the prevalence of self-reported nonadherence in Pulmonary Hypertension Association Registry (PHAR) participants with PAH or chronic thromboembolic pulmonary hypertension and the relationship of nonadherence with several patient-centered outcomes (mortality, hospitalization rates, emergency department visits, and health-related quality of life). Methods Self-reported PAH medication nonadherence was captured at PHAR enrollment and during follow-up visits. Predictors of nonadherence were modeled using generalized estimating equations assuming a binary distribution. Outcomes associated with nonadherence were modeled using generalized estimating equations with a Poisson distribution. Results A total of 1,543 patients were included, of whom 1,092 (70.8%) were female and 1,340 (86.8%) had PAH. The overall rate of any self-reported nonadherence was 6.1% (95% confidence interval [CI], 5.3–6.9). Predictors of nonadherence included self-reported male sex at birth (odds ratio [OR], 1.4; 95% CI, 1.0–1.9; P = 0.02), poverty (OR, 1.6; 95% CI, 1.2–2.3; P = 0.01), not being married or partnered (OR, 1.5; 95% CI, 1.1–1.9; P = 0.01), having Medicaid or no health insurance (OR, 2.1; 95% CI, 1.5–2.9; P < 0.001), and having completed high school but not having a college degree (OR, 1.7; 95% CI, 1.1–2.9; P < 0.001). PHAR participants who reported any nonadherence had 50.0% more emergency department visits (P < 0.001), 13.3% more hospital admissions (P = 0.03), and 61.9% more days hospitalized (P = 0.01). No relationship was observed between nonadherence and the type or number of PAH therapies or all-cause mortality. Participants reporting nonadherence had worse mean Short Form-12 scores (P < 0.001) and worse emPHasis-10 scores (P = 0.02). Conclusions The rate of self-reported nonadherence in PHAR registrants was low but was associated with male sex and several social determinants of health. Although the complexity or type of PAH regimen did not appear to influence nonadherence, nonadherence was associated with numerous adverse patient-centered outcomes, including greater healthcare use and worse health-related quality of life. Because of limitations in the structure of the gathered data, relationships between exposure and outcomes were not temporally definitive; these observations warrant additional prospective studies.
Erratum: Health disparities and treatment approaches in portopulmonary hypertension and idiopathic pulmonary arterial hypertension: An analysis of the Pulmonary Hypertension Association Registry
Background Current mortality data for pulmonary arterial hypertension (PAH) in the United States are based on registries that enrolled patients prior to 2010. We sought to determine mortality in PAH in the modern era using the PHAR (Pulmonary Hypertension Association Registry). Methods and Results We identified all adult patients with PAH enrolled in the PHAR between September 2015 and September 2020 (N=935). We used Kaplan‐Meier survival analysis and Cox proportional hazards models to assess mortality at 1, 2, and 3 years. Patients were stratified based on disease severity by 3 validated risk scores. In treatment‐naïve patients, we compared survival based on initial treatment strategy. The median age was 56 years (44–68 years), and 76% were women. Of the 935 patients, 483 (52%) were ≤6 months from PAH diagnosis. There were 121 deaths (12.9%) during a median follow‐up time of 489 days (281–812 days). The 1‐, 2‐, and 3‐year mortality was 8% (95% CI, 6%–10%), 16% (95% CI, 13%–19%), and 21% (95% CI, 17%–25%), respectively. When stratified into low‐, intermediate‐, and high‐risk PAH, the mortality at 1, 2, and 3 years was 1%, 4% to 6%, and 7% to 11% for low risk; 7% to 8%, 11% to 16%, and 18% to 20% for intermediate risk; and 12% to 19%, 22% to 38%, and 28% to 55% for high risk, respectively. In treatment‐naïve patients, initial combination therapy was associated with better 1‐year survival (adjusted hazard ratio, 0.43 [95% CI, 0.19–0.95]; P =0.037). Conclusions Mortality in the intermediate‐ and high‐risk patients with PAH remains unacceptably high in the PHAR, suggesting the importance for early diagnosis, aggressive use of available therapies, and the need for better therapeutics.
Health‐related quality of life and hospitalizations in chronic thromboembolic pulmonary hypertension versus idiopathic pulmonary arterial hypertension: an analysis from the Pulmonary Hypertension Association Registry (PHAR)
Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare, morbid, potentially curable subtype of pulmonary hypertension that negatively impacts health‐related quality of life (HRQoL). Little is known about differences in HRQoL and hospitalization between CTEPH patients and idiopathic pulmonary arterial hypertension (IPAH) patients. Using multivariable linear regression and mixed effects models, we examined differences in HRQoL assessed by emPHasis‐10 (E10) and SF‐12 between CTEPH and IPAH patients in the Pulmonary Hypertension Association Registry, a prospective multicenter cohort of patients newly evaluated at a Pulmonary Hypertension Care Center. Multivariable negative binomial regression models were used to estimate incidence rate ratios (IRR) for hospitalization amongst the two groups. We included 461 IPAH patients and 169 CTEPH patients. Twenty‐one percent of CTEPH patients underwent pulmonary thromboendarterectomy (PTE) before the end of follow‐up. At baseline, patients with CTEPH had significantly worse HRQoL (higher E10 scores) (ß 2.83, SE 1.11, p = 0.01); however, differences did not persist over time. CTEPH patients had higher rates of hospitalization (excluding the hospitalization for PTE) compared to IPAH patients after adjusting for age, sex, body mass index, WHO functional class and six‐minute walk distance (IRR 1.66, 95%CI 1.04–2.65, p = 0.03). CTEPH patients who underwent PTE had improved HRQoL as compared to those who were medically managed, but patients who underwent PTE were younger, had higher cardiac outputs and greater six‐minute walk distances. In this large, prospective, multicenter cohort, CTEPH patients had significantly worse baseline HRQoL and higher rates of hospitalizations than those with IPAH. CTEPH patients who underwent PTE had significant improvements in HRQoL.
Health disparities and treatment approaches in portopulmonary hypertension and idiopathic pulmonary arterial hypertension: an analysis of the Pulmonary Hypertension Association Registry
Compared to idiopathic pulmonary arterial hypertension (IPAH), patients with portopulmonary hypertension (POPH) have worse survival. Health disparities may contribute to these differences but have not been studied. We sought to compare socioeconomic factors in patients with POPH and IPAH and to determine whether socioeconomic status and/or POPH diagnosis were associated with treatment and health‐care utilization. We performed a cross‐sectional study of adults enrolled in the Pulmonary Hypertension Association Registry. Patients with IPAH (n = 344) and POPH (n = 57) were compared. Compared with IPAH, patients with POPH were less likely to be college graduates (19.6% vs. 34.9%, p = 0.02) and more likely to be unemployed (54.7% vs. 30.5%, p < 0.001) and have an annual household income below poverty level (45.7% vs. 19.0%, p < 0.001). Patients with POPH had similar functional class, quality of life, 6‐min walk distance, and mean pulmonary arterial pressure with a higher cardiac index. Compared with IPAH, patients with POPH were less likely to receive combination therapy (46.4% vs. 62.2%, p = 0.03) and endothelin receptor antagonists (28.6% vs. 55.1%, p < 0.001) at enrollment with similar treatment at follow‐up. Patients with POPH had more emergency department visits (1.7 ± 2.1 vs. 0.9 ± 1.2, p = 0.009) and hospitalizations in the six months preceding enrollment (1.5 ± 2.1 vs. 0.8 ± 1.1, p = 0.02). Both POPH diagnosis and lower education level were independently associated with a higher number of emergency department visits. Compared to IPAH, patients with POPH have lower socioeconomic status, are less likely to receive initial combination therapy and endothelin receptor antagonists but have similar treatment at follow‐up, and have increased health‐care utilization.
Prediction of Health-related Quality of Life and Hospitalization in Pulmonary Arterial Hypertension: The Pulmonary Hypertension Association Registry