Angiotensin Receptor Neprilysin Inhibitor Use and Blood Pressure Lowering in Patients With Heart Failure With Reduced Ejection Fraction Across the Spectrum of Kidney Function: An Analysis of the Veterans Administrative Health System.

BACKGROUND: A substantial proportion of patients with heart failure and kidney disease have poorly controlled blood pressures. This study aimed to evaluate patterns of blood pressure after initiation of an angiotensin receptor neprilysin inhibitor (ARNI) or an angiotensin-converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB) across the spectrum of kidney function. METHODS: Between 2016 and 2020, we evaluated 26,091 patients admitted to a Veterans Affairs hospital for an acute heart failure exacerbation with reduced ejection fraction. We assessed patterns of systolic and diastolic blood pressure among those started on ARNI or ACEI/ARB over 6 months, overall and across estimated glomerular filtration rate (eGFR). To account for differential treatment factors, we applied 1:1 propensity score matching using 15 known baseline covariates. RESULTS: There were 13,781 individuals treated with an ACEI or ARB and 2589 individuals treated with an ARNI prescription. After propensity score matching, 839 patients were matched in each of the ARNI and ACEI/ARB groups. Mean baseline estimated glomerular filtration rate (eGFR) was 63.8 (standard deviation 21.6), and 10% had stage 4 or 5 chronic kidney disease. Patients in the ARNI group experienced greater systolic blood pressure reduction at month 3 (-5.2 mmHg vs -2.2 mmHg, ARNI vs ACEI/ARB; P < 0.001), and month 6 (-4.7 mmHg vs -1.85 mmHg, ARNI vs ACEI/ARB; P < 0.001). These differences in systolic blood pressure by 6 months did not vary by eGFR above and below 60 mL/min/1.73m2 or continuously across a wide range of eGFR (Pinteraction > 0.10 for both). CONCLUSION: The use of ARNI was associated with significant reduction in blood pressure as compared to the ACEI/ARB group overall and across the eGFR spectrum, including in advanced chronic kidney disease.

Complement Drives Synaptic Degeneration and Progressive Cognitive Decline in the Chronic Phase after Traumatic Brain Injury.

Cognitive deficits following traumatic brain injury (TBI) remain a major cause of disability and early-onset dementia, and there is increasing evidence that chronic neuroinflammation occurring after TBI plays an important role in this process. However, little is known about the molecular mechanisms responsible for triggering and maintaining chronic inflammation after TBI. Here, we identify complement, and specifically complement-mediated microglial phagocytosis of synapses, as a pathophysiological link between acute insult and a chronic neurodegenerative response that is associated with cognitive decline. Three months after an initial insult, there is ongoing complement activation in the injured brain of male C57BL/6 mice, which drives a robust chronic neuroinflammatory response extending to both hemispheres. This chronic neuroinflammatory response promotes synaptic degeneration and predicts progressive cognitive decline. Synaptic degeneration was driven by microglial phagocytosis of complement-opsonized synapses in both the ipsilateral and contralateral brain, and complement inhibition interrupted the degenerative neuroinflammatory response and reversed cognitive decline, even when therapy was delayed until 2 months after TBI. These findings provide new insight into our understanding of TBI pathology and its management; and whereas previous therapeutic investigations have focused almost exclusively on acute treatments, we show that all phases of TBI, including at chronic time points after TBI, may be amenable to therapeutic interventions, and specifically to complement inhibition.SIGNIFICANCE STATEMENT There is increasing evidence of a chronic neuroinflammatory response after traumatic brain injury (TBI), but little is known about the molecular mechanisms responsible for triggering and maintaining chronic inflammation. We identify complement, and specifically complement-mediated microglial phagocytosis of synapses, as a pathophysiological link between acute insult and a chronic neurodegenerative response, and further that this response is associated with cognitive decline. Complement inhibition interrupted this response and reversed cognitive decline, even when therapy was delayed until 2 months after injury. The data further support the concept that TBI should be considered a chronic rather than an acute disease condition, and have implications for the management of TBI in the chronic phase of injury, specifically with regard to the therapeutic application of complement inhibition.