The evolving clinical management of hypertension

Uncontrolled blood pressure and its risk factors among hypertensive patients, Marrakech, Morocco

Hypertension is a public health problem. Failure to control blood pressure figures is responsible for morbidity and premature mortality. This study aims to describe the characteristics of hypertensive patients followed at primary health care centers in Marrakech. Between May 2021 and December 2022, a cross-sectional study of 922 hypertension patients attending primary health care centers in Marrakech was done. To gather socio-demographic, behavioral, and clinical data, as well as hypertension treatment features and the care-patient-physician triad, a face-to-face questionnaire was employed. To identify risk factors associated with uncontrolled blood pressure, multivariate logistic regression was used. Uncontrolled blood pressure was found in 73.5% of people. The patients' average age was 63.4 ± 9.4 years (mean ± standard deviation), and 524 (77.3%) were women. Tobacco consumption (Adjusted Odd Ratio of 4.34; 95% CI [1.58-11.9]); lack of self-monitoring of hypertension (AOR of 1.69; 95% CI [1.14-2.52]); a family history of hypertension (AOR of 1.58; 95% CI [1.12-2.22]); overweight or obesity (AOR of 1.73; 95% CI [1.15-2.58]); and nonadherence to antihypertensive medication (AOR of 1.58; 95% CI [1.05-2.38]) were identified as risk factors for uncontrolled blood pressure. In hypertensive individuals, the percentage of uncontrolled blood pressure is considerable. It is essential to provide therapeutic education classes for hypertension patients in order to strengthen their power and autonomy in managing their hypertension.

Hypertension Subtypes among Thai Hypertensives: An Analysis of Telehealth-Assisted Instrument in Home Blood Pressure Monitoring Nationwide Pilot Project

Background

White-coat hypertension (HT), masked HT, HT with white-coat effect, and masked uncontrolled HT are well-recognized problems of over- and undertreatment of high blood pressure in real-life practice. However, little is known about the true prevalence in Thailand.

Objectives

To examine the prevalence and characteristics of each HT subtype defined by mean home blood pressure (HBP) and clinic blood pressure (CBP) using telemonitoring technology in Thai hypertensives.

Methods

A multicenter, observational study included adult hypertensives who had been diagnosed for at least 3 months based on CBP without the adoption of HBP monitoring. All patients were instructed to manually measure their HBP twice a day for the duration of at least one week using the same validated automated, oscillometric telemonitoring devices (Uright model TD-3128, TaiDoc Corporation, Taiwan). The HBP, CBP, and baseline demographic data were recorded on the web-based system. HT subtypes were classified according to the treatment status, CBP (≥or <140/90 mmHg), and mean HBP (≥or <135/85 mmHg) into the following eight subtypes: in nonmedicated hypertensives, there are four subtypes that are normotension, white-coat HT, masked HT, and sustained HT; in treated hypertensives, there are four subtypes that are well-controlled HT, HT with white-coat effect, masked uncontrolled HT, and sustained HT.

Results

Of the 1,184 patients (mean age 58 ± 12.7 years, 59% women) from 46 hospitals, 1,040 (87.8%) were taking antihypertensive agents. The majority of them were enrolled from primary care hospitals (81%). In the nonmedicated group, the prevalence of white-coat and masked HT was 25.7% and 7.0%, respectively. Among the treated patients, the HT with white-coat effect was found in 23.3% while 46.7% had uncontrolled HBP (a combination of the masked uncontrolled HT (9.6%) and sustained HT (37.1%)). In the medicated older subgroup (n = 487), uncontrolled HBP was more prevalent in male than in female (53.6% vs. 42.4%, p=0.013).

Conclusions

This is the first nationwide study in Thailand to examine the prevalence of HT subtypes. Almost one-fourth had white-coat HT or HT with white-coat effect. Approximately half of the treated patients especially in the older males had uncontrolled HBP requiring more intensive interventions. These results emphasize the role of HBP monitoring for appropriate HT diagnosis and management. The cost-effectiveness of utilizing THAI HBPM in routine practice needs to be examined in the future study.

Carotid sinus denervation ameliorates renovascular hypertension in adult Wistar rats

KEY POINTS

Peripheral chemoreflex sensitization is a feature of renovascular hypertension. Carotid sinus nerve denervation (CSD) has recently been shown to relieve hypertension and reduce sympathetic activity in other rat models of hypertension. We show that CSD in renovascular hypertension halts further increases in blood pressure. Possible mechanisms include improvements in baroreceptor reflex sensitivity and renal function, restoration of cardiac calcium signalling towards control levels, and reduced neural inflammation. Our data suggest that the peripheral chemoreflex may be a viable therapeutic target for renovascular hypertension.

ABSTRACT

The peripheral chemoreflex is known to be hyper-responsive in both spontaneously hypertensive (SHR) and Goldblatt hypertensive (two kidney one clip; 2K1C) rats. We have previously shown that carotid sinus nerve denervation (CSD) reduces arterial blood pressure (ABP) in SHR. In the present study, we show that CSD ameliorates 2K1C hypertension and reveal the potential underlying mechanisms. Adult Wistar rats were instrumented to record ABP via telemetry, and then underwent CSD (n = 9) or sham CSD (n = 9) 5 weeks after renal artery clipping, in comparison with normal Wistar rats (n = 5). After 21 days, renal function was assessed, and tissue was collected to assess sympathetic postganglionic intracellular calcium transients ([Ca²⁺ ]_i ) and immune cell infiltrates. Hypertensive 2K1C rats showed a profound elevation in ABP (Wistar: 98 ± 4 mmHg vs. 2K1C: 147 ± 8 mmHg; P < 0.001), coupled with impairments in renal function and baroreflex sensitivity, increased neuroinflammatory markers and enhanced [Ca²⁺ ]_I in stellate neurons (P < 0.05). CSD reduced ABP in 2K1C+CSD rats and prevented the further progressive increase in ABP seen in 2K1C+sham CSD rats, with a between-group difference of 14 ± 2 mmHg by week 3 (P < 0.01), which was accompanied by improvements in both baroreflex control and spectral indicators of cardiac sympatho-vagal balance. Furthermore, CSD improved protein and albuminuria, decreased [Ca²⁺ ]_i evoked responses from stellate neurons, and also reduced indicators of brainstem inflammation. In summary, CSD in 2K1C rats reduces the hypertensive burden and improves renal function. This may be mediated by improvements in autonomic balance, functional remodelling of post-ganglionic neurons and reduced inflammation. Our results suggest that the peripheral chemoreflex may be considered as a potential therapeutic target for controlling renovascular hypertension.

The function and regulation of acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC): IUPHAR Review 19

Acid-sensing ion channels (ASICs) and the epithelial Na(+) channel (ENaC) are both members of the ENaC/degenerin family of amiloride-sensitive Na(+) channels. ASICs act as proton sensors in the nervous system where they contribute, besides other roles, to fear behaviour, learning and pain sensation. ENaC mediates Na(+) reabsorption across epithelia of the distal kidney and colon and of the airways. ENaC is a clinically used drug target in the context of hypertension and cystic fibrosis, while ASIC is an interesting potential target. Following a brief introduction, here we will review selected aspects of ASIC and ENaC function. We discuss the origin and nature of pH changes in the brain and the involvement of ASICs in synaptic signalling. We expose how in the peripheral nervous system, ASICs cover together with other ion channels a wide pH range as proton sensors. We introduce the mechanisms of aldosterone-dependent ENaC regulation and the evidence for an aldosterone-independent control of ENaC activity, such as regulation by dietary K(+) . We then provide an overview of the regulation of ENaC by proteases, a topic of increasing interest over the past few years. In spite of the profound differences in the physiological and pathological roles of ASICs and ENaC, these channels share many basic functional and structural properties. It is likely that further research will identify physiological contexts in which ASICs and ENaC have similar or overlapping roles.

Improved Blood Pressure Control Using an Interactive Mobile Phone Support System

This explorative, longitudinal study evaluated the effect of the daily use of a mobile phone-based self-management support system for hypertension in reducing blood pressure (BP) among 50 primary care patients with hypertension over 8 weeks. The self-management system comprises modules for (1) self-reports of BP, pulse, lifestyle, symptoms, and well-being; (2) delivery of reminders and encouragements; and (3) graphical feedback of self-reports. Daily use of the support system significantly reduced BP (systolic BP -7 mm Hg, diastolic BP -4.9 mm Hg) between baseline and week 8, with daily improvements leveling off as the study progressed. Three homogenous subsets of patients were identified who, despite different initial BP levels, showed similar decreases in BP during the study, indicating that patients benefited irrespective of baseline BP. In showing significant reductions in BP, our results suggest that the self-management support system may be a useful tool in clinical practice to help patients self-manage their hypertension.

Difficult Hypertension Clinic Utilizing a Nurse Specialist: A Cost-Efficient Model for the Modern Era?

In the modern era in New Zealand, there has been a lack of specialist hypertension clinics where family practitioners might refer patients with difficult-to-treat or resistant hypertension. A new specialist referral hypertension clinic was established in 2009 at North Shore Hospital, Auckland, employing a model of care where much of the follow-up work is done by a nurse specialist. The authors review data from the first 1000 patients discharged from the clinic. Mean (treated) blood pressure improved by -26/12 mm Hg over an average of three visits, two thirds of which were to nurse specialist clinics. The authors propose this as a cost-efficient model that could easily be duplicated in other centers.