Effect of suvorexant on nighttime blood pressure in hypertensive patients with insomnia: The SUPER‐1 study

Clinical studies on pharmacological treatment of hypertension in Japan

Differences in the epidemiology and phenotypes of hypertension in Japan compared with Western countries mean that optimal approaches to the pharmacological management of hypertension should be based on local data. Fortunately, there is a large body of evidence from studies conducted in Japanese populations to inform guidelines and treatment decisions. This article highlights treatment recommendations and BP targets for Japanese patients with hypertension, and summarizes key literature supporting these recommendations. The latest version of the Japanese Society of Hypertension (JSH) guidelines is consistent with US and European guidelines in recommending that the general BP target should be <130/80 mmHg for office blood pressure (BP) and <125/75 mmHg for home BP. There is good local evidence to support these targets. The JSH guidelines also strongly recommend that antihypertensive therapy is managed and monitored based on home BP, due to the closer association of this parameter with cardiovascular risk compared with office BP. Japan is a leader in out-of-office BP research, meaning that there is good evidence for the Japanese recommendations. Key features of antihypertensive agents for use in Japanese patients with hypertension include the ability to reduce stroke risk provide antihypertensive efficacy throughout the 24-h dosing period. Calcium channel blockers appear to be particularly effective in Asian populations, and are the most commonly prescribed agents in Japan. Again consistent with international recommendations, antihypertensive therapy should be started with a combination of agents to maximize the chances of achieving target BP.

Hypertension facilitates age-related diseases. ~ Is hypertension associated with a wide variety of diseases?~

Hypertension, a disease whose prevalence increases with age, induces pathological conditions of ischemic vascular disorders such as cerebral infarction and myocardial infarction due to accelerated arteriosclerosis and circulatory insufficiency of small arteries and sometimes causes hemorrhagic conditions such as cerebral hemorrhage and ruptured aortic aneurysm. On the other hand, as it is said that aging starts with the blood vessels, impaired blood flow associated with vascular aging is the basis for the development of many pathological conditions, and ischemic changes in target organs associated with vascular disorders result in tissue dysfunction and degeneration, inducing organ hypofunction and dysfunction. Therefore, we hypothesized that hypertension is associated with all age-related vascular diseases, and attempted to review the relationship between hypertension and diseases for which a relationship has not been previously well reported. Following our review, we hope that a collaborative effort to unravel age-related diseases from the perspective of hypertension will be undertaken together with experts in various specialties regarding the relationship of hypertension to all pathological conditions.

Targeting Orexin Receptors for the Treatment of Insomnia: From Physiological Mechanisms to Current Clinical Evidence and Recommendations

After a detailed description of orexins and their roles in sleep and other medical disorders, we discuss here the current clinical evidence on the effects of dual (DORAs) or selective (SORAs) orexin receptor antagonists on insomnia with the aim to provide recommendations for their further assessment in a context of personalized and precision medicine. In the last decade, many trials have been conducted with orexin receptor antagonists, which represent an innovative and valid therapeutic option based on the multiple mechanisms of action of orexins on different biological circuits, both centrally and peripherally, and their role in a wide range of medical conditions which are often associated with insomnia. A very interesting aspect of this new category of drugs is that they have limited abuse liability and their discontinuation does not seem associated with significant rebound effects. Further studies on the efficacy of DORAs are required, especially on children and adolescents and in particular conditions, such as menopause. Which DORA is most suitable for each patient, based on comorbidities and/or concomitant treatments, should be the focus of further careful research. On the contrary, studies on SORAs, some of which seem to be appropriate also in insomnia in patients with psychiatric diseases, are still at an early stage and, therefore, do not allow to draw definite conclusions.

Orexin, Sleep, Sympathetic Neural Activity, and Cardiovascular Function

Inadequate sleep duration and quality are associated with reduced cardiovascular health and increased mortality. Experimental evidence points to the sympathetic nervous system as a key mediator in the observed relationship between poor sleep and cardiovascular dysfunction. However, brain mechanisms underpinning the impaired sympathetic function associated with poor sleep remain unclear. Recent evidence suggests the central orexin system, particularly orexins A and B and their receptors, have a key regulatory role for sleep in animal and human models. While orexin system activity has been observed to significantly impact sympathetic regulation in animals, the extension of these findings to humans has been difficult due to an inability to directly assess orexin system activity in humans. However, direct measures of sympathetic activity in populations with narcolepsy and chronic insomnia, 2 sleep disorders associated with deficient and excessive orexin neural activity, have allowed indirect assessment of the relationships between orexin, sleep, and sympathetic regulation. Further, the recent pharmaceutical development of dual orexin receptor antagonists for use in clinical insomnia populations offers an unprecedented opportunity to examine the mechanistic role of orexin in sleep and cardiovascular health in humans. The current review assesses the role of orexin in both sleep and sympathetic regulation from a translational perspective, spanning animal and human studies. The review concludes with future research directions necessary to fully elucidate the mechanistic role for orexin in sleep and sympathetic regulation in humans.

Hypocretins (orexins): The ultimate translational neuropeptides

The hypocretins (Hcrts), also known as orexins, are two neuropeptides produced exclusively in the lateral hypothalamus. They act on two specific receptors that are widely distributed across the brain and involved in a myriad of neurophysiological functions that include sleep, arousal, feeding, reward, fear, anxiety and cognition. Hcrt cell loss in humans leads to narcolepsy with cataplexy (narcolepsy type 1), a disorder characterized by intrusions of sleep into wakefulness, demonstrating that the Hcrt system is nonredundant and essential for sleep/wake stability. The causal link between Hcrts and arousal/wakefulness stabilisation has led to the development of a new class of drugs, Hcrt receptor antagonists to treat insomnia, based on the assumption that blocking orexin-induced arousal will facilitate sleep. This has been clinically validated: currently, two Hcrt receptor antagonists are approved to treat insomnia (suvorexant and lemborexant), with a New Drug Application recently submitted to the US Food and Drug Administration for a third drug (daridorexant). Other therapeutic applications under investigation include reduction of cravings in substance-use disorders and prevention of neurodegenerative disorders such as Alzheimer's disease, given the apparent bidirectional relationship between poor sleep and worsening of the disease. Circuit neuroscience findings suggest that the Hcrt system is a hub that integrates diverse inputs modulating arousal (e.g., circadian rhythms, metabolic status, positive and negative emotions) and conveys this information to multiple output regions. This neuronal architecture explains the wealth of physiological functions associated with Hcrts and highlights the potential of the Hcrt system as a therapeutic target for a number of disorders. We discuss present and future possible applications of drugs targeting the Hcrt system for the treatment of circuit-related neuropsychiatric and neurodegenerative conditions.

The efficacy and safety of dual orexin receptor antagonists in primary insomnia: A systematic review and network meta-analysis

The efficacy and safety of dual orexin receptor antagonists (DORAs) for primary insomnia have been well verified in several large randomized controlled trials (RCTs) over the past several decades. However, there have been few systematic comparisons of different DORAs, and the best DORA for insomniacs has remained unclear. Here, Medline, Embase, Cochrane library, and clinicaltrials.gov were searched for RCTs (through December 31, 2020) to evaluate different DORAs versus a placebo. We pooled data from 13 RCTs. DORAs were superior to the placebo in all efficacy outcomes except the subjective number of awakenings (P = 0.90), but also showed higher risks of somnolence, abnormal dreams, fatigue, and dry mouth (somnolence: P < 0.00001; abnormal dreams: P = 0.03; fatigue: P = 0.001; dry mouth: P = 0.007). No statistical differences were found between any two of the DORAs in terms of primary efficacy outcomes. However, lemborexant yielded the three-highest surfaces under the curve ranking area (SUCRA) values (78.25%, 96.25% and 89.13%). Taken together, we conclude that DORAs are superior to the placebo in terms of efficacy and safety measures.

Treating sleep disorders to improve blood pressure control and cardiovascular prevention: a dream come true?-a narrative review

Hypertension is one of the primary risk factors for heart disease and stroke, the leading causes of death worldwide. Current evidence supports the treatment of high blood pressure (BP) values in order to obtain a substantial reduction of cardiovascular burden. Sleep plays an important role in maintaining nocturnal BP control and nocturnal hypertension which, in turn, can be affected by the presence of sleep disorders. Whilst respiratory disturbances have been extensively studied and their causal role in the development of nocturnal hypertension has been demonstrated in both cross sectional and prospective studies, less is known about the impact of other sleep disorders such as insomnia. In this review, we aim to describe the role of sleep disorders in the development of nocturnal and diurnal hypertension. Furthermore, we aim to discuss the potential impact of the treatment of such sleep disorders on BP values as an adjunct treatment for patients with hypertension.

Type 5 phosphodiesterase (PDE5) and the vascular tree: From embryogenesis to aging and disease

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Vascular development depends on the timely differentiation of endothelial and smooth muscle cells.

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Vascular aging and vascular disease are influenced by endothelial and vascular smooth muscle cell compartments.

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A survey of the literature on the role of PDE5 in vascular development, aging and disease is reported.

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The role of PDE5 on vascular development, aging and disease needs to be further investigated by its genetic ablation.

Vascular tree development depends on the timely differentiation of endothelial and vascular smooth muscle cells. These latter are key players in the formation of the vascular scaffold that offers resistance to the blood flow. This review aims at providing an overview on the role of PDE5, the cGMP-specific phosphodiesterase that historically attracted much attention for its involvement in male impotence, in the regulation of vascular smooth muscle cell function. The overall goal is to underscore the importance of PDE5 expression and activity in this cell type in the context of the organs where its function has been extensively studied.

Key Points of the 2019 Japanese Society of Hypertension Guidelines for the Management of Hypertension

The new 2019 Japanese Society of Hypertension (JSH) guidelines for the management of hypertension are now available; these update the previous guidelines published in 2014. The primary objective of the guideline is to provide all healthcare professionals with a standard management strategy and appropriate antihypertensive treatments to prevent hypertension-related target organ damage and cardiovascular events. The major changes in the new guideline relate to the definition of normal blood pressure (BP) and target BP. The terms 'normal BP' and 'high normal BP' used in the JSH 2014 guidelines are replaced with terms 'high normal BP' and 'elevated BP,' respectively. There was no change to the office BP diagnostic threshold for hypertension (140/90 mmHg). Recommended target office and home BP values for patients with hypertension aged <75 years and/or high-risk patients are <130/80 mmHg and <125/75 mmHg, respectively. Corresponding targets for elderly patients with hypertension (age≥75 years) are 140/90 and 135/85 mmHg, respectively. The goal is that these changes will contribute to reducing cardiovascular events, especially stroke and heart failure, in Japan. The dissemination of the JSH 2019 guidelines and implementation of a home BP-based approach by all general practitioners in Japan might be facilitated by digital hypertension management using health information technology.