Personalized medicine for high blood pressure

Perspectives on improving blood pressure control to reduce the clinical and economic burden of hypertension

The clinical and economic burden of hypertension is high and continues to increase globally. Uncontrolled hypertension has severe but avoidable long-term consequences, including cardiovascular diseases, which are among the most burdensome and most preventable conditions in Europe. Yet, despite clear guidelines on screening, diagnosis and management of hypertension, a large proportion of patients remain undiagnosed or undertreated. Low adherence and persistence are common, exacerbating the issue of poor blood pressure (BP) control. Although current guidelines provide clear direction, implementation is hampered by barriers at the patient-, physician- and healthcare system levels. Underestimation of the impact of uncontrolled hypertension and limited health literacy lead to low adherence and persistence among patients, treatment inertia among physicians and a lack of decisive healthcare system action. Many options to improve BP control are available or under investigation. Patients would benefit from targeted health education, improved BP measurement, individualized treatment or simplified treatment regimens through single-pill combinations. For physicians, increasing awareness of the burden of hypertension, as well as offering training on monitoring and optimal management and provision of the necessary time to collaboratively engage with patients would be useful. Healthcare systems should establish nationwide strategies for hypertension screening and management. Furthermore, there is an unmet need to implement more comprehensive BP measurements to optimize management. In conclusion, an integrative, patient-focused, multimodal multidisciplinary approach to the management of hypertension by clinicians, payers and policymakers, involving patients, is required to achieve long-term improvements in population health and cost-efficiency for healthcare systems.

Primary Prevention of Ischemic Stroke

Ischemic stroke is by far the most common type of cerebrovascular event and remains a major cause of death and disability globally. Despite advancements in acute stroke care, primary prevention is still the most cost-effective approach in reducing the burden of ischemic stroke. The two main strategies for primary stroke prevention include population-wide versus high-risk group interventions. Interventions such as increasing access to primary care, regulation of salt and sugar contents in processed foods, public education, and campaigns to control cerebrovascular risk factors are examples of population-wide interventions. High-risk group interventions, on the other hand, focus on recognition of individuals at risk and aim to modify risk factors in a timely and multifaceted manner. This article provides an overview on conventional modifiable risk factors for ischemic stroke and highlights the emerging risk factors and approaches for high-risk group identification and treatment.

Identifying drug-related attributes to personalise antihypertensive agents: the outcome report of patients receiving metoprolol therapy

Background

Currently, numerous antihypertensive drugs from different pharmacological classes are available; however, blood pressure control is achieved in only less than a third of patients treated for hypertension. Moreover, providing optimal and personalised treatment for hypertension is challenging. Therefore, in this study, we propose a ‘drug-related attributes’ sensitive spectrum. This novel concept can assist clinicians in selecting an optimal antihypertensive drug and improve blood pressure control after examining the attributes of a patient.

Methods

We collected clinical data on attributes related to hypertension and its therapy of inpatients from West China Hospital who received metoprolol therapy and constructed the sensitive spectrum using data-visualisation tools.

Results

Our analysis revealed that haematocrit, haemoglobin, serum creatinine, serum cystatin C, serum urea, age, sex, systolic pressure, diastolic pressure, pulse pressure, and heart rate are metoprolol-related attributes.

Conclusion

Our study showed that all metoprolol-related attributes identified are reasonable and helpful in improving the personalisation of metoprolol therapy. The proposed drug-related attributes spectrum can help personalise antihypertensive medication. Moreover, data-visualisation tools can be effectively used to mine the drug-related attributes sensitive spectrum.

Effects of fast-track anesthesia on miR-1 and neuropeptides in serum of patients undergoing cardiac surgery

Effects of fast-track anesthesia (FTA) on miR-1 and neuropeptides in serum of patients undergoing cardiac surgery were investigated. A total of 147 patients who underwent cardiac surgery at Jining No. 1 people's Hospital from August 2015 to July 2018 were selected. There were 72 patients who received the FTA technology during cardiac surgery in the intervention group, and 75 patients who received routine anesthesia during cardiac surgery in the control group. Venous blood was, respectively, collected before anesthesia (T0), 30 min after artery opening (T1), 60 min after artery opening (T2), and 180 min after artery opening (T3). Expression of serum miR-1 in patients at T0 to T3 were detected by real-time fluorescence quantitative PCR. Expression of neuropeptide indexes such as neuron-specific enolase (NSE), S100β protein (S100β), and amyloid β-protein (Aβ) in serum of patients in the two groups at T0 to T3 were detected by ELISA, and the correlation of expression of serum miR-1, serum NSE, S100β and Aβ was analyzed. There was no significant difference in the expression of serum miR-1 between the two groups at T0 (P>0.05). There was no significant difference in the expression of NSE, S100β and Aβ between the two groups at T0 (P>0.05). Expression of serum NSE, S100β and Aβ in both groups increased gradually, and expression of serum NSE, S100β and Aβ in the intervention group were significantly lower than those in the control group at T1-T3 (P<0.05). There was a positive correlation between expression of serum miR-1, serum NSE, S100β and Aβ (r=0.773, P<0.05; r=0.683, P<0.05; r=0.769, P<0.05). Application of the FTA technology in cardiac surgery can effectively reduce the level of serum miR-1 in patients undergoing surgical treatment and improve their neurological function.

Personalized medicine and treatment approaches in hypertension: current perspectives

In the US, hypertension affects one in three adults. Current guideline-based treatment of hypertension involves little diagnostic testing. A more personalized approach to the treatment of hypertension might be of use. Several methods of personalized treatment have been proposed and vetted to varying degrees. The purpose of this narrative review is to discuss the rationale for personalized therapy in hypertension, barriers to its development and implementation, some influential examples of proposed personalization measures, and a view of future efforts.

Characteristics associated with informed consent for genetic studies in the ACCORD trial

BACKGROUND

Prior studies found that some groups have lower genetic consent rates than others. Participant consent for genetic studies enables randomized trials to examine effects of interventions compared to control in participants with different genotypes.

METHODS

Unadjusted and multivariate associations between genetic consent rates and participant, study, and consent characteristics in 9573 participants approached for genetics consent in the multicenter Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, which used a layered genetics consent.

RESULTS

Eighty-nine percent of eligible participants consented to genetic studies ("Any Consent") and 64.7% consented to studies of any genes by any investigator ("Full Consent"), with similar rates in randomized groups. Controlling for multiple characteristics, African-Americans had lower consent rates than others (Any Consent Odds Ratio, OR = 0.62, p = 0.0004; Full Consent OR = 0.67, p < 0.0001). Those with high school or higher education level had higher rates than less than high school graduates (Full Consent ORs 1.41-1.69, p-values < 0.0001). Consent rates were lower when genetics consent was separate from the main trial consent on the same day (Any Consent OR 0.30; Full Consent OR 0.52, p values < 0.0001) or on a subsequent day (Any Consent OR 0.70, p = 0.0022; Full Consent OR 0.76, p = 0.0002).

CONCLUSION

High rates of consent for genetic studies can be obtained in complex randomized trials, with lower consent rates in African-Americans, in participants with less than high-school education, and for sharing samples with other investigators. A genetics consent separated from the main trial consent was associated with lower consent rates.

Why do hypertensive patients of African ancestry respond better to calcium blockers and diuretics than to ACE inhibitors and β-adrenergic blockers? A systematic review

BACKGROUND

Clinicians are encouraged to take an individualized approach when treating hypertension in patients of African ancestry, but little is known about why the individual patient may respond well to calcium blockers and diuretics, but generally has an attenuated response to drugs inhibiting the renin-angiotensin system and to β-adrenergic blockers. Therefore, we systematically reviewed the factors associated with the differential drug response of patients of African ancestry to antihypertensive drug therapy.

METHODS

Using the methodology of the systematic reviews narrative synthesis approach, we sought for published or unpublished studies that could explain the differential clinical efficacy of antihypertensive drugs in patients of African ancestry. PUBMED, EMBASE, LILACS, African Index Medicus and the Food and Drug Administration and European Medicines Agency databases were searched without language restriction from their inception through June 2012.

RESULTS

We retrieved 3,763 papers, and included 72 reports that mainly considered the 4 major classes of antihypertensive drugs, calcium blockers, diuretics, drugs that interfere with the renin-angiotensin system and β-adrenergic blockers. Pharmacokinetics, plasma renin and genetic polymorphisms did not well predict the response of patients of African ancestry to antihypertensive drugs. An emerging view that low nitric oxide and high creatine kinase may explain individual responses to antihypertensive drugs unites previous observations, but currently clinical data are very limited.

CONCLUSION

Available data are inconclusive regarding why patients of African ancestry display the typical response to antihypertensive drugs. In lieu of biochemical or pharmacogenomic parameters, self-defined African ancestry seems the best available predictor of individual responses to antihypertensive drugs.

Patients with neovascular age-related macular degeneration in Spain display a high cardiovascular risk

PURPOSE

Cardiovascular disease and its risk factors may have a significant role in the development of neovascular age-related macular degeneration (NV-AMD). This study aims to assess the impact of these factors in this population and define their level of cardiovascular risk according to the Framingham model.

METHODS

This was a cross-sectional, observational, multicenter study that included patients aged 50 years or older who attended ophthalmic centers for the diagnosis or follow-up of NV-AMD. Information collected included demographic and AMD data, a complete history of cardiovascular disease and its risk factors, lipid profile, blood pressure, and treatment history.

RESULTS

The study population consisted of 901 patients, predominantly Caucasian, with a mean age of 75.7 years, receiving anti-vascular endothelial growth factor therapy for their NV-AMD in 77.7% of the cases. Blood pressure measurement during the study visit and lipid analyses revealed poor control in 67.7% and 93.3% of the patients, respectively. Hypertension was the most prevalent cardiovascular risk factor (77.7%), followed by a history of cardiac disease or other forms of atherosclerotic disease (53.8%). Diabetes was present in 28% of the subjects. The study population was considered a high-risk population according to the National Cholesterol Education Program Expert Panel Clinical Guidelines (NCEP ATP III), with a probability of a cardiovascular event in 10 years of 19.3% according to the Framingham model.

CONCLUSIONS

This NV-AMD population is associated with a significant cardiovascular risk, and the Framingham model can help us identify those subjects with higher risk levels in order to improve their overall management.

Power to identify a genetic predictor of antihypertensive drug response using different methods to measure blood pressure response

BACKGROUND

To determine whether office, home, ambulatory daytime and nighttime blood pressure (BP) responses to antihypertensive drug therapy measure the same signal and which method provides greatest power to identify genetic predictors of BP response.

METHODS

We analyzed office, home, ambulatory daytime and nighttime BP responses in hypertensive adults randomized to atenolol (N = 242) or hydrochlorothiazide (N = 257) in the Pharmacogenomic Evaluation of Antihypertensive Responses Study. Since different measured BP responses may have different predictors, we tested the "same signal" model by using linear regression methods to determine whether known predictors of BP response depend on the method of BP measurement. We estimated signal-to-noise ratios and compared power to identify a genetic polymorphism predicting BP response measured by each method separately and by weighted averages of multiple methods.

RESULTS

After adjustment for pretreatment BP level, known predictors of BP response including plasma renin activity, race, and sex were independent of the method of BP measurement. Signal-to-noise ratios were more than 2-fold greater for home and ambulatory daytime BP responses than for office and ambulatory nighttime BP responses and up to 11-fold greater for weighted averages of all four methods. Power to identify a genetic polymorphism predicting BP response was directly related to the signal-to-noise ratio and, therefore, greatest with the weighted averages.

CONCLUSION

Since different methods of measuring BP response to antihypertensive drug therapy measure the same signal, weighted averages of the BP responses measured by multiple methods minimize measurement error and optimize power to identify genetic predictors of BP response.

Personalized vascular medicine: individualizing drug therapy

Personalized medicine refers to the application of an individual's biological fingerprint - the comprehensive dataset of unique biological information - to optimize medical care. While the principle itself is straightforward, its implementation remains challenging. Advances in pharmacogenomics as well as functional assays of vascular biology now permit improved characterization of an individual's response to medical therapy for vascular disease. This review describes novel strategies designed to permit tailoring of four major pharmacotherapeutic drug classes within vascular medicine: antiplatelet therapy, antihypertensive therapy, lipid-lowering therapy, and antithrombotic therapy. Translation to routine clinical practice awaits the results of ongoing randomized clinical trials comparing personalized approaches with standard of care management.

Prolonged head down bed rest-induced inactivity impairs tonic autonomic regulation while sparing oscillatory cardiovascular rhythms in healthy humans

BACKGROUND

Physical inactivity represents a major risk for cardiovascular disorders, such as hypertension, myocardial infarction or sudden death; however, underlying mechanisms are not clearly elucidated. Clinical and epidemiological investigations suggest, beyond molecular changes, the possibility of an induced impairment in autonomic cardiovascular regulation. However, this hypothesis has not been tested directly.

METHODS

Accordingly, we planned a study with noninvasive, minimally intrusive, techniques on healthy volunteers. Participants were maintained for 90 days strictly in bed, 24 h a day, in head-down (-6 degrees ) position (HDBR). Physical activity was thus virtually abolished for the entire period of HDBR. We examined efferent muscle sympathetic nerve activity, as a measure of vascular sympathetic control, baroreceptor reflex sensitivity, heart rate variability (assessing cardiovagal regulation), RR and systolic arterial pressure and low-frequency and high-frequency normalized components (as a window on central oscillatory regulation). Measures were obtained at rest and during simple maneuvers (moderate handgrip, lower body negative pressure and active standing) to assess potential changes in autonomic cardiovascular responsiveness to standard stimuli and the related oscillatory profiles.

RESULTS

HDBR transiently reduced muscle sympathetic nerve activity, RR, heart rate variability and baroreceptor reflex sensitivity late during HDBR or early during the recovery phase. Conversely, oscillatory profiles of RR and systolic arterial pressure variability were maintained throughout. Responsiveness to test stimuli was also largely maintained.

CONCLUSION

Prolonged inactivity as induced by HDBR in healthy volunteers reduces both cardiovagal and vascular sympathetic regulation, while largely maintaining peripheral responsiveness to standardized stimuli and sparing the functional structure of central oscillatory cardiovascular regulation.

Hemodynamic, autonomic and baroreflex changes after one night sleep deprivation in healthy volunteers

BACKGROUND

Sleep disorders are associated to a number of cardiovascular disturbances that might increase cardiovascular risk. Sleep deprivation, in particular, might, by inducing autonomic dysregulation, raise arterial pressure and hypertensive risk. Available evidence however is contradictory.

METHODS

We tested the main hypothesis that one night sleep deprivation in 24 volunteers might alter hemodynamics (heart rate and Arterial Pressure - AP), autonomic regulation (mono and bivariate spectral analysis of RR and non invasive AP variability) and baroreflex control (spectral index alpha and spontaneous baroreflex slope), performance indices (reaction time) and subjective stress (questionnaires and salivary cortisol). Volunteers were studied in normal living conditions and while kept in isolation and confinement, to test the presence of possible bias related to environmental stress.

RESULTS

Results indicate that there were no differences between normal living conditions and isolation and confinement (Intraclass Correlation Coefficient >0.75 for most variables). Conversely, after one night sleep deprivation subjects felt tired (p<0.05), and performance deteriorated (p<0.05), while cortisol profile was substantially maintained, hemodynamic parameters did not change and HRV and index alpha increased slightly.

CONCLUSIONS

Findings support the contention that one night sleep deprivation, in absence of significant additional stress or disturbances, does not lead to increased arterial pressure values or to changes in autonomic or baroreflex profiles that could conceivably favor hypertension development, but induces the expected increase in tiredness and reduction in performance.

A comparison of the genetic and clinical profile of men that respond and do not respond to the immediate antihypertensive effects of aerobic exercise

We compared the genetic and clinical profile of men who lower and do not lower blood pressure (BP) after acute aerobic exercise. Volunteers were 45 men (Mean ± SEM, 43.5 ± 1.5 yr) with high BP (145.7 ± 1.5/85.7 ± 1.1 mmHg). They completed three experiments: nonexercise control and two cycle exercise sessions at 40% and 60% peak oxygen consumption, and were then instrumented to an ambulatory BP monitor. Logistic regression determined the genetic and clinical profile of men who lowered BP after exercise (responders [ExR n = 36]); and those who did not (nonresponders [ExNR n = 9]). ExR had higher C-reactive protein (CRP), high-density lipoprotein (HDL), the metabolic syndrome, family history of hypertension, more renin-angiotensin system (RAS) common alleles, and α-adducin Trp(460) and endothelial nitric oxide synthase (ENOS) C(786) risk alleles. ExNR had lower CRP and HDL, did not have the metabolic syndrome and a family history of hypertension, had more RAS risk alleles, and had the α-adducin Gly460Gly and ENOS T786T genotypes. This model had a sensitivity of 97.1%, specificity of 75.0%, and accounted for 46.3%-74.4% of the BP response. These results suggest genetic and clinical information may eventually be used to characterize people who do and do not respond to exercise as antihypertensive therapy.

Hypertension-induced renal fibrosis and spironolactone response vary by rat strain and mineralocorticoid receptor gene expression

Introduction. Aldosterone promotes renal fibrosis via the mineralocorticoid receptor (MR), thus contributing to hypertension-induced nephropathy. We investigated whether MR gene expression influences renal fibrosis and MR antagonist response in a two-kidney, one-clip hypertensive rat model.

Materials and methods. Brown Norway (BN), Lewis, and ACI rats were randomised to spironolactone 20 mg/kg/day or water by gavage, starting four weeks after left renal artery clipping. Blood pressure was measured bi-weekly by tail cuff. After eight weeks of treatment, right kidneys were removed and examined for fibrosis and gene expression. Rats of each strain undergoing no intervention served as controls.

Results. Blood pressure increased similarly among strains after clipping and was unaffected by spironolactone. Hypertension caused the greatest renal fibrosis in BN rats (p < 0.001 by ANOVA compared to other strains). Real-time PCR analysis showed greater renal collagen type I and MR gene expression in untreated, hypertensive BN rats (both p < 0.05 compared to other strains). Spironolactone attenuated fibrosis, with similar fibrosis among strains of spironolactone-treated rats.

Conclusion. Hypertension-induced renal fibrosis was greatest in rats with the highest MR gene expression. Spironolactone abolished inter-strain differences in fibrosis. Our data suggest that MR genotype may influence aldosterone-induced renal damage, and consequently, renal response to aldosterone antagonism.

Genomic association analysis suggests chromosome 12 locus influencing antihypertensive response to thiazide diuretic

We conducted a genome-wide association study to identify novel genes influencing diastolic blood pressure (BP) response to hydrochlorothiazide, a commonly prescribed thiazide diuretic preferred for the treatment of high BP. Affymetrix GeneChip Human Mapping 100K Arrays were used to measure single nucleotide polymorphisms across the 22 autosomes in 194 non-Hispanic black subjects and 195 non-Hispanic white subjects with essential hypertension selected from opposite tertiles of the race- and sex-specific distributions of age-adjusted diastolic BP response to hydrochlorothiazide (25 mg daily, PO, for 4 weeks). The black sample consisted of 97 "good" responders (diastolic BP response [mean+/-SD]=-18.3+/-4.2 mm Hg; age=47.1+/-6.1 years; 51.5% women) and 97 "poor" responders (diastolic BP response=-0.18+/-4.3; age=47.4+/-6.5 years; 51.5% women). Haplotype trend regression identified a region of chromosome 12q15 in which haplotypes constructed from 3 successive single nucleotide polymorphisms (rs317689, rs315135, and rs7297610) in proximity to lysozyme (LYZ), YEATS domain containing 4 (YEATS4), and fibroblast growth receptor substrate 2 (FRS2) were significantly associated with diastolic BP response (nominal P=2.39 x 10(-7); Bonferroni corrected P=0.024; simulated experiment-wise P=0.040). Genotyping of 35 additional single nucleotide polymorphisms selected to "tag" linkage disequilibrium blocks in these genes provided corroboration that variation in LYZ and YEATS4 was associated with diastolic BP response in a statistically independent data set of 291 black subjects and in the sample of 294 white subjects. These results support the use of genome-wide association analyses to identify novel genes influencing antihypertensive drug responses.

Physiological and pathophysiological roles of extracellular ATP in chemosensory control of breathing

The purine nucleotide ATP mediates several distinct forms of sensory transduction in both the peripheral and central nervous systems. These processes share common mechanisms that involve the release of ATP to activate ionotropic P2X and/or metabotropic P2Y receptors. Extracellular ATP signalling plays an important role in ventilatory control, mediating both peripheral and central chemosensory transduction to changes in arterial levels of oxygen and carbon dioxide. New data also suggest that extracellular ATP may play an important role in mediating certain neurophysiological responses to systemic inflammation. Here, we propose the novel concept that both peripheral and central neurophysiological effects of ATP may contribute to alterations in ventilatory control during inflammatory pathophysiological states.

Intact microtubules are required for natriuretic responses to nitric oxide and increased renal perfusion pressure

Extracellular renal interstitial (RI) cGMP modulates NO- and pressure-induced natriuresis in vivo in the rat. The present study objective was to test the hypothesis that an intact microtubulin network is required for transport of cGMP from intracellular sites into the extracellular compartment in vivo and that this transport is required for natriuresis induced by NO and increased renal perfusion pressure. After a 1-hour control period, uninephrectomized rats received an RI infusion of NO donor S-nitroso-N-acetylpenicillamine (SNAP), SNAP+microtubule inhibitor nocodazole (NOC), SNAP+NOC+cGMP, or NOC alone for 2 consecutive 1-hour collection periods. SNAP alone increased RI cGMP (P<0.05 during both experimental periods) and urinary sodium excretion (P<0.05 at 1 hour and P<0.005 at 2 hours). In contrast, when SNAP+NOC were coinfused, there was no increase in either RI cGMP or urinary sodium excretion. However, when cGMP was coinfused with SNAP+NOC, the natriuretic response to SNAP was fully restored. Similarly, NOC abolished SNAP-induced increases in the fractional excretion of Na(+) and Li(+). NOC also prevented the increase in both RI cGMP and natriuresis engendered by raising renal perfusion pressure in uninephrectomized rats, and pressure-natriuresis was re-established by coadministration of RI cGMP. As demonstrated by confocal microscopy after in vivo renal perfusion fixation, beta-tubulin was disrupted in renal cortical nephrons of kidneys infused intrarenally with NOC. These observations indicate that a functioning microtubulin network is required for the transport of cGMP into the extracellular space to modulate NO- and pressure-induced natriuresis.