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Competing Interests: The authors report no conflicts of interest.

Background and Purpose- Albuminuria is associated with stroke risk among individuals with diabetes. However, the association of albuminuria with incident stroke among nondiabetic patients is less clear. Methods- We performed a post hoc analysis of the SPRINT (Systolic Blood Pressure Intervention Trial), which examined the effect of higher versus lower intensity blood pressure management on mortality in 8913 participants without diabetes. We fit unadjusted and adjusted Cox proportional hazards models to estimate the association of baseline albuminuria (urinary albumin-to-creatinine ratio ≥30 mg/g versus<30 mg/g) with stroke risk. We also assessed effect modification according to treatment arms. Results- Mean age was 68±9 years, 35% were female, and 30% were black. Median follow-up was 3.2 years, and 19% patients had baseline albuminuria. Incident stroke occurred in 129 individuals during follow-up. Albuminuria was associated with increased stroke risk (unadjusted hazard ratio, 2.24; 95% CI, 1.55-3.23; adjusted hazard ratio 1.73; 95% CI, 1.17-2.56). The association of albuminuria with incident stroke differed according to the randomized treatment arm ( P interaction=0.03). In the intensive treatment arm, the association of albuminuria and stroke was nonsignificant (unadjusted hazard ratio, 1.25; 95% CI, 0.69-2.28), whereas, in the standard treatment arm, it was significant (unadjusted hazard ratio, 3.44; 95% CI, 2.11-5.61). Conclusions- In a post hoc analysis of SPRINT, baseline albuminuria (versus not) was associated with a higher risk of incident stroke, but this relationship appeared to be restricted to those in the standard treatment arm. Further studies are required to conclusively determine if reduction of albuminuria in itself is beneficial in reducing stroke risk. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT01206062.

Objectives: Septic shock is a life-threatening clinical situation associated with acute myocardial and vascular dysfunction, whose pathophysiology is still poorly understood. Herein, we investigated microRNA-155-dependent mechanisms of myocardial and vascular dysfunction in septic shock., Design: Prospective, randomized controlled experimental murine study and clinical cohort analysis., Setting: University research laboratory and ICU at a tertiary-care center., Patients: Septic patients, ICU controls, and healthy controls. Postmortem myocardial samples from septic and nonseptic patients. Ex vivo evaluation of arterial rings from patients undergoing coronary artery bypass grafting., Subjects: C57Bl/6J and genetic background-matched microRNA-155 knockout mice., Interventions: Two mouse models of septic shock were used. Genetic deletion and pharmacologic inhibition of microRNA-155 were performed. Ex vivo myographic studies were performed using mouse and human arterial rings., Measurements and Main Results: We identified microRNA-155 as a highly up-regulated multifunctional mediator of sepsis-associated cardiovascular dysfunction. In humans, plasma and myocardial microRNA-155 levels correlate with sepsis-related mortality and cardiac injury, respectively, whereas in murine models, microRNA-155 deletion and pharmacologic inhibition attenuate sepsis-associated cardiovascular dysfunction and mortality. MicroRNA-155 up-regulation in septic myocardium was found to be mostly supported by microvascular endothelial cells. This promoted myocardial microvascular permeability and edema, bioenergetic deterioration, contractile dysfunction, proinflammatory, and nitric oxide-cGMP-protein kinase G signaling overactivation. In isolate cardiac microvascular endothelial cells, microRNA-155 up-regulation significantly contributes to LPS-induced proinflammatory cytokine up-regulation, leukocyte adhesion, and nitric oxide overproduction. Furthermore, we identified direct targeting of CD47 by microRNA-155 as a novel mechanism of myocardial and vascular contractile depression in sepsis, promoting microvascular endothelial cell and vascular insensitivity to thrombospondin-1-mediated inhibition of nitric oxide production and nitric oxide-mediated vasorelaxation, respectively. Additionally, microRNA-155 directly targets angiotensin type 1 receptor, decreasing vascular angiotensin II reactivity. Deletion of microRNA-155 restored angiotensin II and thrombospondin-1 vascular reactivity in LPS-exposed arterial rings., Conclusions: Our study demonstrates multiple new microRNA-155-mediated mechanisms of sepsis-associated cardiovascular dysfunction, supporting the translational potential of microRNA-155 inhibition in human septic shock.