Publications

Hemodynamic forces regulate vascular functions. Disturbed flow (DF) occurs in arterial bifurcations and curvatures, activates endothelial cells (ECs), and results in vascular inflammation and ultimately atherosclerosis. However, how DF alters EC metabolism, and whether resulting metabolic changes induce EC activation, is unknown. Using transcriptomics and bioenergetic analysis, we discovered that DF induces glycolysis and reduces mitochondrial respiratory capacity in human aortic ECs. DF-induced metabolic reprogramming required hypoxia inducible factor-1α (), downstream of NAD(P)H oxidase-4 ()-derived reactive oxygen species (ROS). increased glycolytic enzymes and pyruvate dehydrogenase kinase-1 (), which reduces mitochondrial respiratory capacity. Swine aortic arch endothelia exhibited elevated ROS, , , and glycolytic enzyme and expression, suggesting that DF leads to metabolic reprogramming in vivo. Inhibition of glycolysis reduced inflammation suggesting a causal relationship between flow-induced metabolic changes and EC activation. These findings highlight a previously uncharacterized role for flow-induced metabolic reprogramming and inflammation in ECs.

Health policies encourage implementing quality measurement with performance targets. The 2010-2015 California Medicaid waiver mandated quality measurement and reporting. In 2013, California safety net hospitals participating in the waiver set a voluntary performance target (the 90th percentile for Medicare preferred provider organization plans) for mammography screening and cholesterol control in diabetes. They did not reach the target, and the difference-in-differences analysis suggested that there was no difference for mammography ( P = .39) and low-density lipoprotein control ( P = .11) performance compared to measures for which no statewide quality improvement initiative existed. California's Medicaid waiver was associated with improved performance on a number of metrics, but this performance was not attributable to target setting on specific health conditions. Performance may have improved because of secular trends or systems improvements related to waiver funding. Relying on condition-specific targets to measure performance may underestimate improvements and disadvantage certain health systems. Achieving ambitious targets likely requires sustained fiscal, management, and workforce investments.