King, Wendy C.

ABSTRACT Background Pulmonary arterial hypertension (PAH) is characterized by circulating metabolic alterations, but whether these reflect disease-specific metabolic programs or reorganization of normal metabolic architecture, and how they relate to right ventricular-pulmonary vascular function (RV-PV), remains unclear. We hypothesized that the PAH metabolome is organized into biologically coherent, co-regulated metabolic modules whose relationships to RV-PV function would provide insight into known and novel metabolic pathways. Methods We applied weighted gene co-expression network analysis (WGCNA) to untargeted metabolomic data from 412 PAH patients enrolled in the multicenter PVDOMICS study. Module preservation analysis was performed in 85 healthy controls, with external replication in an independent single-center pulmonary hypertension cohort of 89 patients. Results WGCNA identified 16 distinct metabolic modules organized around biologically coherent programs. A coherent fatty acid axis, spanning substrate pools, β-oxidation intermediates, and conjugated fatty acid disposal products, formed a central organizing structure, with downstream fatty acid oxidation modules strongly associated with adverse hemodynamics and worse RV-pulmonary artery (PA) coupling. Acylcholine-enriched and 5α-reduced androgen metabolite modules were associated with favorable hemodynamic indices. Module architecture was largely preserved in healthy controls, with subtle disease-associated modular reorganization, rather than emergence of novel modules, observed in PAH. Core modules were recovered in the replication cohort with conserved hub metabolites. Conclusions These findings establish a systems-level framework demonstrating that PAH involves structured intensification and reorganization of interconnected metabolic programs associated with favorable and adverse RV-PV phenotypes. This work provides new insight into the metabolic architecture underlying PAH and identifies coordinated metabolic pathways linked to pulmonary vascular and right ventricular function.

ImportanceDisparities in treatment initiation may affect outcomes, but data on racially diverse populations with chronic hepatitis B virus (HBV) infection are limited.ObjectiveTo examine whether HBV treatment initiation and outcomes differ among racial groups.Design, Setting, and ParticipantsFrom January 14, 2011, to January 28, 2018, hepatitis B surface antigen—positive adults (age ≥18 years) not receiving anti-HBV therapy were enrolled and followed up at weeks 12, 24, and every 24 weeks thereafter in a multicenter longitudinal cohort study (Hepatitis B Research Network [HBRN] adult cohort study) conducted in North America. The last study visit and data collection were completed January 28, 2019. Data were analyzed from August 27, 2021, to August 25, 2022. All HBRN participants were included unless they had acute HBV, HIV, hepatitis C or D, less than 24-weeks of follow-up after enrollment, initiated treatment at or immediately after enrollment, or had unknown race.ExposuresParticipants had clinical and laboratory assessments and could receive anti-HBV treatment after enrollment.Main Outcomes and MeasuresHepatitis B virus treatment initiation and major adverse liver outcomes (hepatic decompensation, hepatocellular carcinoma, liver transplant, and death).ResultsOf 1550 participants, 193 (12%) were African American or Black, 1157 (75%) were Asian, 157 (10%) were White, and 43 (3%) were other races; 789 (51%) were women, and the median age was 41.2 (IQR, 32.9-51.6) years. Sociodemographic and virologic parameters differed between groups. During 5727 person-years of follow-up, 504 participants initiated treatment, with incidences of 4.8 per 100 person-years in African American or Black individuals, 9.9 per 100 person-years in Asian individuals, 6.6 per 100 person-years in White individuals, and 7.9 per 100 person-years in those of other races (P < .001). A lower proportion (14%) of African American or Black participants met treatment criteria compared with Asian (22%) and White (27%) individuals (P = .01). The cumulative probabilities of treatment initiation after meeting the criteria were not significantly different among racial groups (African American or Black, 0.45; Asian, 0.38; White, 0.40 at 48 weeks and African American or Black, 0.45; Asian, 0.51; White, 0.51 at 72 weeks; P = .68). The incidence of major adverse liver outcomes was 0.1 per 100 person-years and did not differ by race.Conclusions and RelevanceIn this observational study of chronic HBV, African American or Black participants were less likely than individuals of other races to meet treatment criteria, but among those who did, HBV treatment receipt did not differ significantly by race or socioeconomic factors. Not all eligible participants initiated treatment, but adverse liver outcomes were rare. These findings may not be generalizable to patients with chronic HBV receiving care in other settings.

ObjectiveTo determine effects of physical activity (PA) with diet‐induced weight loss on energy metabolism in adults with severe obesity.MethodsAdults with severe obesity (n = 11) were studied across 6 months of intervention, then compared with controls with less severe obesity (n = 7) or normal weight (n = 9). Indirect calorimetry measured energy metabolism during exercise and rest. Markers of muscle oxidation were determined by immunohistochemistry. Data were presented as medians.ResultsThe intervention induced 7% weight loss (P = 0.001) and increased vigorous PA by 24 min/wk (P = 0.02). During exercise, energy expenditure decreased, efficiency increased (P ≤ 0.03), and fatty acid oxidation (FAO) did not change. Succinate dehydrogenase increased (P = 0.001), but fiber type remained the same. Post‐intervention subjects’ resting metabolism remained similar to controls. Efficiency was lower in post‐intervention subjects compared with normal‐weight controls exercising at 25 W (P ≤ 0.002) and compared with all controls exercising at 60% VO2peak (P ≤ 0.019). Resting and exercise FAO of post‐intervention subjects remained similar to adults with less severe obesity. Succinate dehydrogenase and fiber type were similar across all body weight statuses.ConclusionsWhile metabolic adaptations to PA during weight loss occur in adults with severe obesity, FAO does not change. Resulting FAO during rest and exercise remains similar to adults with less severe obesity.