Raza, Farhan

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.

Abstract Deep phenotyping of pulmonary hypertension (PH) with multimodal diagnostic exercise interventions can lead to early focused therapeutic interventions. Herein, we report methods to simultaneously assess pulmonary impedance, differential biventricular myocardial strain, and right ventricular:pulmonary arterial (RV:PA) uncoupling during exercise, which we pilot in subjects with suspected PH. As proof-of-concept, we show that four subjects with different diagnoses [pulmonary arterial hypertension (PAH); chronic thromboembolic disease (CTEPH); PH due to heart failure with preserved ejection fraction (PH-HFpEF); and noncardiac dyspnea (NCD)] have distinct patterns of response to exercise. RV:PA coupling assessment with exercise was highest-to-lowest in this order: PAH > CTEPH > PH-HFpEF > NCD. Input impedance (Z0) with exercise was highest in precapillary PH (PAH, CTEPH), followed by PH-HFpEF and NCD. Characteristic impedance (ZC) tended to decline with exercise, except for the PH-HFpEF subject (initial Zc increase at moderate workload with subsequent decrease at higher workload with augmentation in cardiac output). Differential myocardial strain was normal in PAH, CTEPH, and NCD subjects and lower in the PH-HFpEF subject in the interventricular septum. The combination of these metrics allowed novel insights into mechanisms of RV:PA uncoupling. For example, while the PH-HFpEF subject had hemodynamics comparable to the NCD subject at rest, with exercise coupling dropped precipitously, which can be attributed (by decreased myocardial strain of interventricular septum) to poor support from the left ventricle (LV). We conclude that this deep phenotyping approach may distinguish afterload sensitive vs. LV-dependent mechanisms of RV:PA uncoupling in PH, which may lead to novel therapeutically relevant insights.