Background: A relationship between hypertension and risk of incident cardiovascular disease, coronary artery disease, and stroke is widely reported in type 2 diabetes. However, trials testing intensive blood pressure control therapy versus standard therapy to reduce cardiovascular events have reported conflicting results, which could potentially be due to an unmeasured biological factor such as the common Hp (haptoglobin) phenotype.
Methods: Multivariable-adjusted Cox proportional hazards regression models assessed the relationship between intensive (versus standard) blood pressure control therapy and risk of composite cardiovascular disease, coronary artery disease, and stroke events in the ACCORD (Action to Control Cardiovascular Risk in Diabetes) blood pressure trial in participants with the Hp2-2 phenotype (n=1527) separately from Hp1 allele carriers (n=2748).
Results: Intensive blood pressure therapy (versus standard therapy) was associated with a lower risk of composite cardiovascular disease among Hp1 allele carriers (hazard ratio, 0.76 [95% CI, 0.59-0.99]) but not among participants with the Hp2-2 phenotype (hazard ratio, 1.12 [95% CI, 0.80-1.55]; P-interaction=0.07). No significant hazard ratio was observed for intensive therapy versus standard therapy on risk of coronary artery disease (Hp1 allele carriers: hazard ratio, 0.85 [95% CI, 0.67-1.08]; Hp2-2 phenotype: hazard ratio, 1.12 [95% CI, 0.84-1.51]; P-interaction=0.11). Intensive therapy was associated with a lower risk of stroke among Hp1 allele carriers (hazard ratio, 0.53 [95% CI, 0.31-0.91]) but not among Hp2-2 participants (hazard ratio, 0.70 [95% CI, 0.33-1.46]; P-interaction=0.56).
Conclusions: The lack of an effect of intensive blood pressure control on composite cardiovascular disease events in the original ACCORD blood pressure trial may be explained in part by variation in response among the Hp phenotypes. Further study and replication are required.
Registration: URL: https://www.clinicaltrials.gov/study/NCT00000620?id=NCT00000620; Unique identifier: NCT00000620.
The second Asia Renal Denervation Consortium consensus conference shared information and developed updated recommendations for renal denervation (RDN). Current evidence confirms that RDN significantly reduces blood pressure across all metrics (office, home, and ambulatory) throughout 24 hours. Modern RDN approaches target the distal main renal artery and branches where nerves more closely approximate the vessel wall. Understanding renal artery anatomy is crucial; the main renal artery typically divides into anterior and posterior divisions as first-order branches, which further subdivide into second-order segmental arterial branches. Renal artery electrical stimulation shows promise as a procedural end point, with blood pressure response attenuation after successful RDN suggesting adequate denervation, though the optimal procedural end point remains to be established. The indication for RDN is resistant or uncontrolled hypertension, with high office, home, or 24-hour ambulatory blood pressure readings despite appropriate lifestyle modification and antihypertensive drug therapy. Preprocedure assessment includes comprehensive screening for secondary causes and detailed renal artery imaging. Checklists for preprocedure and postprocedure assessment are provided. Nocturnal hypertension and morning hypertension, which are common in Asia, are more closely associated with cardiovascular risk than daytime hypertension and are more difficult to control with current guideline-driven medication. Based on these Asian characteristics and RDN's long-term durability, RDN should be considered an effective option for facilitating optimal 24-hour blood pressure control. Future research through real-world data collection will help determine ethnic differences in RDN response between Asians and Westerners and identify optimal candidates. In addition, studies are needed to evaluate RDN's ability to prevent organ damage and cardiovascular events.
Background: Ang II (angiotensin II) causes hypertension and vascular inflammation both directly and indirectly via cytokines, including TNFα (tumor necrosis factor-α). In vascular smooth muscle cells (VSMCs), Ang II and TNFα activate Nox1 (NADPH oxidase 1) to produce superoxide. TNFα receptors associate with Nox1 and LRRC8A (leucine-rich repeat containing 8A) anion channels to modulate inflammation and contractility in a RhoA-dependent manner. VSMC-specific LRRC8A knockout mesenteric arteries are protected from TNFα-induced injury, and vasodilation is preserved. We hypothesized that LRRC8A knockout would preserve vascular function and decrease blood pressure (BP) in Ang II-infused mice.
Methods: Wild-type and knockout mice received Ang II infusions for 14 days. BP was measured by radiotelemetry, and aortic and mesenteric artery function was measured by wire myography. VSMCs were isolated from male wild-type and knockout mice.
Results: Systolic BP was not different, but knockout mice had more BP dipping during inactive periods at baseline, and dipping was preserved after Ang II. The function of knockout aortic and mesenteric vessels was less impaired by Ang II, as reflected by less augmented contraction to norepinephrine and serotonin and preserved relaxation to acetylcholine and sodium nitroprusside. Western blotting revealed increased soluble guanylate cyclase alpha and reduced CPI-17 in hypertensive knockout aortae. Consistent with lower Rho kinase activity, phosphorylation of ERM (ezrin/radixin/moesin) and cofilin was reduced in knockout VSMCs. Ang II caused less proliferation (lower PCNA [proliferating cell nuclear antigen]) and less induction of senescence in knockout vessels.
Conclusions: LRRC8A anion channels support VSMC inflammation and the associated vascular dysfunction, which impairs BP dipping in hypertension.
Background: The rice diet (RD), a low-sodium (<200 mg/d), low-protein (≈20 g/d), and low-fat (<5 g/d) diet was used to treat patients with malignant hypertension beginning in the 1940s, before any effective antihypertensive drugs were available. We retrospectively analyzed a curated cohort of RD patients with malignant hypertension to assess factors, including dietary adherence, associated with blood pressure (BP) reduction.
Methods: From 17 487 RD charts, we identified 544 malignant hypertension patients (baseline systolic BP ≥170 mm Hg and with concurrent retinal hemorrhage or papilledema), excluding those with diabetes, brain tumor, or prior sympathectomy. Outcome data were censored after any 30-day break in consecutive data. Baseline features, BP changes from baseline to week 4, and diet adherence (assessed by urinary chloride, UCl) were evaluated using summary statistics, univariate, and multivariable analyses.
Results: Most patients participated in the RD program before antihypertensive drugs were available; only 48 (8.8%) received any antihypertensive medications in the first month. The cohort (68.9% male) had a median baseline BP of 213/128 mm Hg and body mass index of 23.6 kg/m2. Median time in the program before censoring was 109 days; median total time in the RD program was 333 days. BP declined significantly within the first week, reaching 179/108 mm Hg at week 4. UCl dropped from 217 to 21 mg/dL by week 4. Lower UCl, higher baseline BP, and female sex, but not retinal hemorrhage or papilledema, were associated with greater systolic BP reduction.
Conclusions: The low-sodium, low-fat, low-protein RD effectively lowered BP in malignant hypertension patients in 4 weeks, independent of antihypertensive medications.
Background: Chronic unfolded protein response due to endoplasmic reticulum stress has been proposed as a therapeutic target for hypertension. Here, we tested our hypothesis that inactivation of one of the central unfolded protein response effectors, inositol-requiring enzyme 1α, mitigates hypertension and vascular remodeling in mice infused with angiotensin II.
Methods: C57BL6 mice were infused with angiotensin II for 2 weeks with or without an inositol-requiring enzyme 1α inhibitor KIRA6 treatment to evaluate blood pressure and cardiovascular remodeling. Mouse small mesenteric arteries were used to assess vascular reactivity. Rat vascular smooth muscle cells were used to assess inositol-requiring enzyme 1α activation, intracellular Ca2+ concentration, and secretory phenotype via proteomics.
Results: KIRA6 treatment mitigated hypertension induced by angiotensin II infusion. KIRA6 treatment also prevented angiotensin II-induced vascular thickening and perivascular fibrosis. Immunohistochemical staining of aortas indicated that phosphorylated inositol-requiring enzyme 1α signal in vascular smooth muscle cells was elevated with angiotensin II infusion and attenuated with KIRA6 treatment. Vasoconstriction in small mesenteric arteries after incubation with angiotensin II was attenuated by KIRA6 coincubation. Angiotensin II-induced elevation in intracellular Ca2+ concentration was partially reduced by KIRA6 pretreatment in vascular smooth muscle cells. Proteomic analysis demonstrated that angiotensin II induced a unique secretory phenotype in vascular smooth muscle cells, which was mitigated by KIRA6.
Conclusions: Targeting inositol-requiring enzyme 1α is a potential therapy for hypertension and vascular remodeling by reducing vascular resistance, mitigating intracellular Ca2+ elevation, and protecting against secretory phenotype in vascular smooth muscle cells.

