Can we identify response markers to antihypertensive drugs? First results from the IDEAL Trial

Polygenic scores for cardiovascular risk factors improve estimation of clinical outcomes in CCB treatment compared to pharmacogenetic variants alone

Pharmacogenetic variants are associated with clinical outcomes during Calcium Channel Blocker (CCB) treatment, yet whether the effects are modified by genetically predicted clinical risk factors is unknown. We analyzed 32,000 UK Biobank participants treated with dihydropiridine CCBs (mean 5.9 years), including 23 pharmacogenetic variants, and calculated polygenic scores for systolic and diastolic blood pressures, body fat mass, and other patient characteristics. Outcomes included treatment discontinuation and heart failure. Pharmacogenetic variant rs10898815-A (NUMA1) increased discontinuation rates, highest in those with high polygenic scores for fat mass. The RYR3 variant rs877087 T-allele alone modestly increased heart failure risks versus non-carriers (HR:1.13, p = 0.02); in patients with high polygenic scores for fat mass, lean mass, and lipoprotein A, risks were substantially elevated (HR:1.55, p = 4 × 10-5). Incorporating polygenic scores for adiposity and lipoprotein A may improve risk estimates of key clinical outcomes in CCB treatment such as treatment discontinuation and heart failure, compared to pharmacogenetic variants alone.

Estrogen-mediated mechanisms in hypertension and other cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of death globally for men and women. Premenopausal women have a lower incidence of hypertension and other cardiovascular events than men of the same age, but diminished sex differences after menopause implicates 17-beta-estradiol (E2) as a protective agent. The cardioprotective effects of E2 are mediated by nuclear estrogen receptors (ERα and ERβ) and a G protein-coupled estrogen receptor (GPER). This review summarizes both established as well as emerging estrogen-mediated mechanisms that underlie sex differences in the vasculature during hypertension and CVD. In addition, remaining knowledge gaps inherent in the association of sex differences and E2 are identified, which may guide future clinical trials and experimental studies in this field.

Heterogeneity in Blood Pressure Response to 4 Antihypertensive Drugs: A Randomized Clinical Trial

Importance

Hypertension is the leading risk factor for premature death worldwide. Multiple blood pressure-lowering therapies are available but the potential for maximizing benefit by personalized targeting of drug classes is unknown.

Objective

To investigate and quantify the potential for targeting specific drugs to specific individuals to maximize blood pressure effects.

Design, Setting, and Participants

A randomized, double-blind, repeated crossover trial in men and women with grade 1 hypertension at low risk for cardiovascular events at an outpatient research clinic in Sweden. Mixed-effects models were used to assess the extent to which individuals responded better to one treatment than another and to estimate the additional blood pressure lowering achievable by personalized treatment.

Interventions

Each participant was scheduled for treatment in random order with 4 different classes of blood pressure-lowering drugs (lisinopril [angiotensin-converting enzyme inhibitor], candesartan [angiotensin-receptor blocker], hydrochlorothiazide [thiazide], and amlodipine [calcium channel blocker]), with repeated treatments for 2 classes.

Main Outcomes and Measures

Ambulatory daytime systolic blood pressure, measured at the end of each treatment period.

Results

There were 1468 completed treatment periods (median length, 56 days) recorded in 270 of the 280 randomized participants (54% men; mean age, 64 years). The blood pressure response to different treatments varied considerably between individuals (P < .001), specifically for the choices of lisinopril vs hydrochlorothiazide, lisinopril vs amlodipine, candesartan vs hydrochlorothiazide, and candesartan vs amlodipine. Large differences were excluded for the choices of lisinopril vs candesartan and hydrochlorothiazide vs amlodipine. On average, personalized treatment had the potential to provide an additional 4.4 mm Hg-lower systolic blood pressure.

Conclusions and Relevance

These data reveal substantial heterogeneity in blood pressure response to drug therapy for hypertension, findings that may have implications for personalized therapy.

Trial Registration

ClinicalTrials.gov Identifier: NCT02774460.

Sex and gender differences in the treatment of arterial hypertension

INTRODUCTION

Arterial hypertension represents the leading modifiable risk factor for all-cause death and early development of cardiovascular disease in women. Current clinical guidelines for the treatment of hypertension noted that women respond to antihypertensive drugs similarly to men and, therefore, treatment recommendations remain the same for both sexes. However, clinical evidence suggests the existence of sex- and gender-related differences (SGRD) in the prevalence, pathophysiology, pharmacodynamics (efficacy and safety) and pharmacokinetics of antihypertensive drugs.

AREAS COVERED

This review summarizes SGRD in the prevalence of hypertension, hypertension-mediated organ damage and blood pressure control, prescription patterns, and pharmacokinetics/ pharmacodynamics and doses of antihypertensive drugs.

EXPERT OPINION

There is limited information on SGRD in antihypertensive drug efficacy because of the underrepresentation of women in randomized clinical trials and, more important, because few trials reported results stratified by sex or performed sex-specific analyses. However, there are SGRD in hypertension-mediated organ damage, drug pharmacokinetics and, particularly, in drug safety. Prospective trials specifically designed to better understand the basis for SGRD in the pathophysiology of hypertension and in the efficacy and safety of antihypertensive drugs are needed to achieve a more personalized treatment of hypertension and hypertension-mediated organ damage in women.

Systematic review on sex differences for drug use after stroke

INTRODUCTION

Systematic reviews and meta-analyses have synthetized the existing knowledge on sex-differences for the risk of stroke, the most recent ones highlighting an increased risk of stroke for women. However, whether there are sex differences in post stroke treatment in real world setting is not known. We therefore conducted a systematic review on this subject.

MATERIAL AND METHODS

All observational studies on sex-differences in poststroke drug use published until 20/04/2021 were identified from PubMed and Scopus. Articles were selected and assessed by two independent readers; a third resolved disagreements. Data extraction was performed using a standardized form; articles quality was assessed using the STROBE guidelines. The study is registered on PROSPERO: CRD42021250256.

RESULTS

Of the 604 identified articles, 33 were included. Most were published before 2015 and presented methodological limitations. These limitations differentially affected studies with statistically significant and non-significant results, questioning the reliability of conflicting results. The exploration of sex-differences in drug use varied between therapeutic classes (articles focusing on thrombolytics: 25; antithrombotics: 23; on antihypertensive: 13; lipid-lowering drugs: 9). After stroke, women were found less likely to be prescribed antithrombotics in 48% of the articles investigating this class, and lipid-lowering drugs in 56%. Thirty-one percent of the studies concerning antihypertensive drugs reported the opposite.

DISCUSSION/CONCLUSION

In women, a lack of use of antithrombotics and lipid-lowering drugs after stroke seem to emerge from this review. Conflicting results regarding sex-differences might relate to methodological limitations in studies with no statistical differences, and advocate for the conduct of newer and more comprehensive research.

Sex differences in hypertension. Do we need a sex-specific guideline?

Hypertension is the most prevalent cardiovascular disorder and the leading cause of death worldwide in both sexes. The prevalence of hypertension is lower in premenopausal women than in men of the same age, but sharply increases after the menopause, resulting in higher rates in women aged 65 and older. Awareness, treatment, and control of hypertension are better in women. A sex-pooled analysis from 4 community-based cohort studies found increasing cardiovascular risk beginning at lower systolic blood pressure thresholds for women than men. Hormonal changes after the menopause play a substantial role in the pathophysiology of hypertension in postmenopausal women. Female-specific causes of hypertension such as the use of contraceptive agents and assisted reproductive technologies have been identified. Hypertensive disorders in pregnancy are associated with increased risk of maternal, fetal, and neonatal morbidity and mortality, as well as with a greater risk of developing cardiovascular disease later in life. Hypertension-mediated organ damage was found to be more prevalent in women, thus increasing the cardiovascular risk. Sex differences in pharmacokinetics have been observed, but their clinical implications are still a matter of debate. There are currently no sufficient data to support sex-based differences in the efficacy of antihypertensive treatment. Adverse drug reactions are more frequently reported in women. Women are still underrepresented in large clinical trials in hypertension, and not all of them report sex-specific results. Therefore, it is of utmost importance to oblige scientists to include women in clinical trials and to consider sex as a biological variable.

Testing treatment-by-period interaction in four-period crossover trials

Statistical analyses of crossover clinical trials have mainly focused on assessing the treatment effect, carryover effect, and period effect. When a treatment-by-period interaction is plausible, it is important to test such interaction first before making inferences on differences among individual treatments. Considerably less attention has been paid to the treatment-by-period interaction, which has historically been aliased with the carryover effect in two-period or three-period designs. In this article, from the data of a newly developed four-period crossover design, we propose a statistical method to compare the effects of two active drugs with respect to two response variables. We study estimation and hypothesis testing considering the treatment-by-period interaction. Constrained least squares is used to estimate the treatment effect, period effect, and treatment-by-period interaction. For hypothesis testing, we extend a general multivariate method for analyzing the crossover design with multiple responses. Results from simulation studies have shown that this method performs very well. We also illustrate how to apply our method to the real data problem.

Hypertension Across a Woman's Life Cycle

Hypertension accounts for 1 in 5 deaths among American women, posing a greater burden for women than men, and is among their most important risk factors for death and development of cardiovascular and other diseases. Hypertension affects women in all phases of life, with specific characteristics relating to risk factors and management for primary prevention of hypertension in teenage and young adult women; hypertension in pregnancy; hypertension during use of oral contraceptives and assisted reproductive technologies, lactation, menopause, or hormone replacement; hypertension in elderly women; and issues of race and ethnicity. All are detailed in this review, as is information relative to women in clinical trials of hypertension and medication issues. The overarching message is that effective treatment and control of hypertension improves cardiovascular outcomes. But many knowledge gaps persist, including the contribution of hypertensive disorders of pregnancy to cardiovascular disease risk, the role of hormone replacement, blood pressure targets for elderly women, and so on.

Blood pressure response to metoprolol and chlorthalidone in European and African Americans with hypertension

Despite the availability of many antihypertensive drug classes, half of patients with hypertension have uncontrolled blood pressure (BP). The authors sought to assess the effect of age on BP response in European American and African American patients with hypertension. Clinic BP from the PEAR2 (Pharmacogenomics Evaluation of Antihypertensive Responses 2) study was used to estimate BP responses from baseline following sequential treatment with metoprolol 100 mg twice daily and chlorthalidone 25 mg daily for 8 to 9 weeks each, with a minimum 4-week washout between treatments. BP responses to both drugs were compared in 159 European Americans and 119 African Americans by age with adjustment for baseline BP and sex. European Americans younger than 50 years responded better to metoprolol than chlorthalidone (diastolic BP: -9.6 ± 8.0 vs -5.9 ± 6.8 mm Hg, adjusted P = .003), whereas patients 50 years and older responded better to chlorthalidone than metoprolol (systolic BP: -18.7 ± 13.8 vs -13.6 ± 14.8 mm Hg, adjusted P = .008). African Americans younger than 50 years responded similarly to both drugs, whereas those 50 years and older responded better to chlorthalidone than metoprolol (-17.0 ± 13.2/-9.6 ± 7.5 vs -7.0 ± 18.6/-6.7 ± 9.3 mm Hg, adjusted P<.0001/.008). Therefore, age should be considered when selecting antihypertensive therapy in European and African American populations with hypertension.

Advances in understanding the renin-angiotensin-aldosterone system (RAAS) in blood pressure control and recent pivotal trials of RAAS blockade in heart failure and diabetic nephropathy

The renin-angiotensin-aldosterone system (RAAS) plays a fundamental role in the physiology of blood pressure control and the pathophysiology of hypertension (HTN) with effects on vascular tone, sodium retention, oxidative stress, fibrosis, sympathetic tone, and inflammation. Fortunately, RAAS blocking agents have been available to treat HTN since the 1970s and newer medications are being developed. In this review, we will (1) examine new anti-hypertensive medications affecting the RAAS, (2) evaluate recent studies that help provide a better understanding of which patients may be more likely to benefit from RAAS blockade, and (3) review three recent pivotal randomized trials that involve newer RAAS blocking agents and inform clinical practice.