Detection of Nonadherence to Antihypertensive Treatment by Measurements of Serum Drug Concentrations

Novel biomarkers in patients with uncontrolled hypertension with and without kidney damage

INTRODUCTION

Estimated glomerular filtration rate (eGFR) and urine albumin/creatinine ratio (ACR) are insensitive biomarkers for early detection of hypertension-mediated organ damage (HMOD). In this nationwide cross-sectional study, we assessed potential biomarkers for early HMOD in healthy persons and patients with hypertension. We hypothesised that plasma levels of biomarkers: (1) are different between healthy controls and patients with hypertension, (2): can classify patients with hypertension according to the degree of hypertension severity.

DESIGN AND METHODS

Patients with hypertension prescribed ≥2 antihypertensive agents were selected from a multicentre study. Healthy controls were selected from an ongoing study of living kidney donor candidates. Uncontrolled hypertension was defined as systolic daytime ambulatory blood pressure ≥135 mmHg. Kidney HMOD was defined by ACR > 3.0 mg/mmol or eGFR < 60 mL/min/1.73 m2. Patients with hypertension were categorised into three groups: (1) controlled hypertension; (2) uncontrolled hypertension without kidney HMOD; (3) uncontrolled hypertension with kidney HMOD. Fifteen biomarkers were analysed using a Luminex bead-based immunoassay, and nine fell within the specified analytical range.

RESULTS

Plasma levels of Interleukin 1 receptor antagonist (IL-1RA), neutrophil gelatinase-associated lipocalin (NGAL) and uromodulin were significantly different between healthy controls (n = 39) and patients with hypertension (n = 176). In regression models, with controlled hypertension (n = 55) as the reference category, none of the biomarkers were associated with uncontrolled hypertension without (n = 59) and with (n = 62) kidney HMOD. In models adjusted for cardiovascular risk factors and eGFR, osteopontin (OPN) was associated with uncontrolled hypertension without kidney HMOD (odds ratio (OR) 1.77 (1.05-2.98), p = 0.03), and regulated upon activation normal T-cell expressed and secreted (RANTES) with uncontrolled hypertension with kidney HMOD (OR 0.57 (0.34-0.95), p = 0.03).

CONCLUSIONS

None of the biomarkers could differentiate our hypertension groups when established risk factors were considered. Plasma OPN may identify patients with uncontrolled hypertension at risk for kidney HMOD.

Effect of Therapeutic Drug Monitoring on Adherence and Blood Pressure: A Multicenter Randomized Clinical Trial

BACKGROUND

Drug concentration in blood or urine is an acknowledged method to detect nonadherence. Observational studies suggest that informing patients about low or absent serum drug levels improves blood pressure (BP). We performed a multicenter randomized clinical trial to test the hypothesis that therapeutic drug monitoring (TDM) could improve drug adherence and BP in patients with uncontrolled hypertension (HT).

METHODS

Patients were ≥18 years on stable treatment with at least 2 antihypertensive agents. We planned to randomize 80 nonadherent patients with a systolic daytime ambulatory BP ≥135 mm Hg to TDM intervention or not. The control group and the study personnel who measured BP remained uninformed about serum drug measurements throughout. All patients and physicians were blinded for BPs. Lifestyle advice and detailed information on the disease process and the importance of BP treatment were given to both groups.

RESULTS

From 2017 to 2022, we randomized 46 diagnosed nonadherent from a total of 606 patients with uncontrolled HT. The TDM group had a 6.7 (±14.5) mm Hg reduction from 147.9 (±10.3) to 141.1 (±14.1) mm Hg, and the control group experienced a 7.3 (±13.2) mm Hg reduction from 147.1 (±9.2) to 139.1 (±17.4) mm Hg, P = 0.9 between groups. Adherence improved in both groups, 73% in the TDM group and 59% in the control group became adherent at 3 months, P = 0.51.

CONCLUSIONS

In our prospective multicenter clinical trial of uncontrolled and nonadherent hypertensive patients, we found no additional effect of TDM on BP and drug adherence compared with standard care.

CLINICAL TRIALS REGISTRATION

Trial Number NCT03209154, www.clinicaltrials.gov.

Single-pill combination for treatment of hypertension: Just a matter of practicality or is there a real clinical benefit?

Elevated blood pressure (BP) is the largest contributor to the incident cardiovascular disease worldwide. Despite explicit guideline recommendations for the diagnosis and management of hypertension, a large proportion of patients remain undiagnosed, untreated, or treated but uncontrolled. Inadequate BP control is associated with many complex factors including patient preference, physician's inertia, health systems disparities, and poor adherence to prescribed antihypertensive drug treatment. The primary driver for reduced cardiovascular morbidity and mortality is lowering of BP ''per se'' and not class effects of specific pharmacotherapies. The recent ESH guidelines recommend the use of four major classes of drugs including renin-angiotensin-aldosterone system (RAS) blockers (angiotensin receptor blockers (ARB) or angiotensin-converting enzyme inhibitors (ACEi)), calcium channel blockers (CCB), thiazide and thiazide-like diuretics, and betablockers. Initiation of treatment for hypertension with a two-drug regimen, preferably in a single pill combination (SPC), is recommended for most patients. Preferred combinations should comprise a RAS blocker (either an ACEi or an ARB) with a CCB or thiazide/thiazide-like diuretic. These strategies are supported by robust evidence that combination therapy produces greater BP reductions than monotherapy, reduces side effects of the individual components, improves therapeutic adherence and long-term persistence on treatment, and permits achievement of earlier BP control.

Medical Measures in Hypertensives Considered Resistant

BACKGROUND

Patients with resistant hypertension are the group of hypertensive patients with the highest cardiovascular risk.

METHODS

All rules and guidelines for treatment of hypertension should be followed strictly to obtain blood pressure (BP) control in resistant hypertension. The mainstay of treatment of hypertension, also for resistant hypertension, is pharmacological treatment, which should be tailored to each patient's specific phenotype. Therefore, it is pivotal to assess nonadherence to pharmacological treatment as this remains the most challenging problem to investigate and manage in the setting of resistant hypertension.

RESULTS

Once adherence has been confirmed, patients must be thoroughly worked-up for secondary causes of hypertension. Until such possible specific causes have been clarified, the diagnosis is apparent treatment-resistant hypertension (TRH). Surprisingly few patients remain with true TRH when the various secondary causes and adherence problems have been detected and resolved. Refractory hypertension is a term used to characterize the treatment resistance in hypertensive patients using ≥5 antihypertensive drugs. All pressor mechanisms may then need blockage before their BPs are reasonably controlled.

CONCLUSIONS

Patients with resistant hypertension need careful and sustained follow-up and review of their medications and dosages at each term since medication adherence is a very dynamic process.

Gender Differences in Cardiac Organ Damage in Arterial Hypertension: Assessing the Role of Drug Nonadherence

INTRODUCTION

Cardiac organ damage like left ventricular (LV) hypertrophy and left atrial (LA) enlargement is more prevalent in women than men with hypertension, but the mechanisms underlying this gender difference remain unclear.

METHODS

We tested the association of drug nonadherence with the presence of LV hypertrophy and LA enlargement by echocardiography in 186 women and 337 men with uncontrolled hypertension defined as daytime systolic blood pressure (BP) ≥ 135mmHg despite the prescription of at least two antihypertensive drugs. Drug adherence was assessed by measurements of serum drug concentrations interpreted by an experienced pharmacologist. Aldosterone-renin-ratio (ARR) was measured on actual medication.

RESULTS

Women had a higher prevalence of LV hypertrophy (46% vs. 33%) and LA enlargement (79% vs 65%, both p < 0.05) than men, while drug nonadherence (8% vs. 9%, p > 0.514) did not differ. Women were older and had lower serum renin concentration and higher ARR than men, while 24-h systolic BP (141 ± 9 mmHg vs. 142 ± 9 mmHg), and the prevalences of obesity (43% vs. 50%) did not differ (all p > 0.10). In multivariable analyses, female gender was independently associated with a two-fold increased risk of LV hypertrophy (OR 2.01[95% CI 1.30-3.10], p = 0.002) and LA enlargement (OR 1.90 [95% CI 1.17-3.10], p = 0.010), while no association with drug nonadherence was found. Higher ARR was independently associated with LV hypertrophy in men only (OR 2.12 [95% CI 1.12-4.00] p = 0.02).

CONCLUSIONS

Among patients with uncontrolled hypertension, the higher prevalence of LV hypertrophy and LA enlargement in women was not explained by differences in drug nonadherence.

REGISTRATION

URL:  https://www.

CLINICALTRIALS

gov ; Unique identifier: NCT03209154.

Therapy and guideline adherence at a multidisciplinary hypertension clinic: A prospective, observational study

BACKGROUND

Hypertension is highly prevalent and remains one of the most frequent and preventable causes of cardiovascular morbidity and mortality. Yet, suboptimal blood pressure control is common. Hypertension clinics might play an important role in improving target attainment, by targeting drug therapy adherence, improving guideline compliance and by involving pharmacists.

OBJECTIVES

We aimed to characterize patient drug therapy adherence, prescriber guideline compliance and pharmacist interventions at the hypertension clinic.

METHODS

A prospective observational study was performed at the hypertension clinic of a large, academic hospital. Adult Dutch-speaking patients were eligible for inclusion. Following data were collected: patient demographics, medication use, patient adherence to prescribed antihypertensive drug therapies according to the BAASIS tool and prescriber compliance to the 2018 European Society of Cardiology (ESC) hypertension guidelines.

RESULTS

A cohort of 108 patients was included with 51.9% male and aged 65 (IQR: 52-75) years. In total, 104 patients took at least 1 antihypertensive drug and 46 patients (44.2%) were classified as non-adherent with regard to their antihypertensive treatment; 82 patients (78.8%) had suboptimal blood pressure control. Compliance with the ESC guidelines was 66.3% prior to the consultation at the clinic and significantly increased to 77.9% thereafter (p = 0.0015). The clinical pharmacist performed a medication review for 27 patients with a total of 44 recommendations and an acceptance rate of 59.1%.

CONCLUSION

A visit to the multidisciplinary hypertension clinic improved prescriber guideline compliance and the use of single pill combinations. Involvement of a clinical pharmacist could be beneficial to further improve patient drug therapy adherence and guideline compliance.

Contribution of single-pill combinations in the management of hypertension: perspectives from China, Europe and the USA

Uncontrolled hypertension is associated with an increased risk of adverse clinical vascular outcomes and death. Hypertension management guidelines from China and the USA recommend initiation of antihypertensive pharmacotherapy with a single drug for patients without severe hypertension at presentation. Current European hypertension guidelines take a different approach and recommend the use of combination therapy from the time of diagnosis of hypertension for most patients. This article reviews the burden of hypertension in these countries and summarises the evidence base for the use of antihypertensive combination therapy contained within a single tablet (single-pill combinations, SPC). Typically, half or less of populations from China, Europe and the USA who were found to have hypertension were aware of their condition, less than half of those receiving treatment, and fewer still achieved adequate blood pressure (BP) control. The reasons for the unaddressed burden of hypertension are complex and multifactorial, with contributions from factors related to patients, healthcare providers and healthcare systems. The use of SPCs of antihypertensive therapies helps to optimise adherence with therapy and is likely to result in superior BP control. There is a strong evidence base to support current European guideline recommendations on the initiation of antihypertensive therapy with SPCs for the majority of people with hypertension.

On the issue of low adherence of patients to antihypertensive therapy: the use of therapeutic drug monitoring of drugs: A review

Low adherence of patients to antihypertensive therapy remains an urgent problem and is recognized as the main cause of insufficient BP control at the population level. In this regard, to increase the motivation of patients in clinical practice, methods for assessing adherence (compliance) to drugs. Along with indirect assessment methods (questionnaires, self-reports, pill counts, etc.), which, however, do not always reflect the real patients adherence, more objective is the measurement of antihypertensive drug concentrations in physiological fluids therapeutic drug monitoring (TDM). For these purposes, methods of high-performance liquid chromatography with mass spectrometry were recently adapted, reference ranges of antihypertensive drug concentrations in blood serum and urine for standard doses of drugs were determined, as well as criteria for assessing complete or partial non-compliance. There have been a number of studies using TDM to assess adherence, which show a high rate of non-compliance (low compliance) of more than 50% of cases with a variability from 25 to 86.1%, with complete non-compliance 10.134.5% in patients with uncontrolled and/or resistant hypertension (3 antihypertensive drug). In a population of patients with a normal course of hypertension, taking 12 antihypertensive drug, the level of non-compliance according to the results of TDM did not exceed 10%. Comparison of the TDM method with indirect methods of assessing adherence did not reveal consistency; at the same time, the detection of antihypertensive drug better characterized the clinical problems of patients with arterial hypertension. In clinical practice, direct assessment methods (TDM) can be used to measure adherence in problem patients with uncontrolled hypertension and high cardiovascular risk despite optimal therapy.

Nonadherence by Serum Drug Analyses in Resistant Hypertension: 7-Year Follow-Up of Patients Considered Adherent by Directly Observed Therapy

Background Measurement of serum concentrations of drugs is a novelty found useful in detecting poor drug adherence in patients taking ≥2 antihypertensive agents. Regarding patients with treatment-resistant hypertension, we previously based our assessment on directly observed therapy. The present study aimed to investigate whether serum drug measurements in patients with resistant hypertension offer additional information regarding drug adherence, beyond that of initial assessment with directly observed therapy. Methods and Results Nineteen patients assumed to have true treatment-resistant hypertension and adherence to antihypertensive drugs based on directly observed therapy were investigated repeatedly through 7 years. Serum concentrations of antihypertensive drugs were measured by ultra-high-performance liquid chromatography-tandem mass spectrometry from blood samples taken at baseline, 6-month, 3-year, and 7-year visits. Cytochrome P450 polymorphisms, self-reported adherence and beliefs about medicine were performed as supplement investigations. Seven patients (37%) were redefined as nonadherent based on their serum concentrations during follow-up. All patients reported high adherence to medications. Nonadherent patients expressed lower necessity and higher concerns regarding intake of antihypertensive medication (P=0.003). Cytochrome P450 polymorphisms affecting metabolism of antihypertensive drugs were found in 16 patients (84%), 21% were poor metabolizers, and none were ultra-rapid metabolizers. Six of 7 patients redefined as nonadherent had cytochrome P450 polymorphisms, however, not explaining the low serum drug concentrations measured in these patients. Conclusions Our data suggest that repeated measurements of serum concentrations of antihypertensive drugs revealed nonadherence in one-third of patients previously evaluated as adherent and treatment resistant by directly observed therapy, thereby improving the accuracy of adherence evaluation. Registration URL: https://www.clinicaltrials.gov; unique identifier: NCT01673516.

Global Burden, Regional Differences, Trends, and Health Consequences of Medication Nonadherence for Hypertension During 2010 to 2020: A Meta-Analysis Involving 27 Million Patients

Background

Nonadherence to antihypertensive medications is the leading cause of poor blood pressure control and thereby cardiovascular diseases and mortality worldwide.

Methods and Results

We investigated the global epidemiology, regional differences, and trend of antihypertensive medication nonadherence via a systematic review and meta‐analyses of data from 2010 to 2020. Multiple medical databases and clinicaltrials.gov were searched for articles. Observational studies reporting the proportion of patients with anti‐hypertensive medication nonadherence were included. The proportion of nonadherence, publication year, year of first recruitment, country, and health outcomes attributable to antihypertensive medication nonadherence were extracted. Two reviewers screened abstracts and full texts, classified countries according to levels of income and locations, and extracted data. The Joanna Briggs Institute prevalence critical appraisal tool was used to rate the included studies. Prevalence meta‐analyses were conducted using a fixed‐effects model, and trends in prevalence were analyzed using meta‐regression. The certainty of evidence concerning the effect of health consequences of nonadherence was rated according to Grading of Recommendations, Assessment, Development and Evaluations. A total of 161 studies were included. Subject to different detection methods, the global prevalence of anti‐hypertensive medication nonadherence was 27% to 40%. Nonadherence was more prevalent in low‐ to middle‐income countries than in high‐income countries, and in non‐Western countries than in Western countries. No significant trend in prevalence was detected between 2010 and 2020. Patients with antihypertensive medication nonadherence had suboptimal blood pressure control, complications from hypertension, all‐cause hospitalization, and all‐cause mortality.

Conclusions

While high prevalence of anti‐hypertensive medication nonadherence was detected worldwide, higher prevalence was detected in low‐ to middle‐income and non‐Western countries. Interventions are urgently required, especially in these regions. Current evidence is limited by high heterogeneity.

Registration

URL: www.crd.york.ac.uk/prospero/; Unique identifier: CRD42021259860.

Adherence and blood pressure control in patients with primary aldosteronism

PURPOSE

The aim of our study was to evaluate the adherence to mineralocorticoid receptor (MR) antagonists and other antihypertensive therapy and blood pressure control in conservatively treated patients with primary aldosteronism (PA).

MATERIALS AND METHODS

Conservatively treated subjects with previously confirmed PA (n-50, 64.5 ± 9 years of age, 24% women) were investigated via our outpatient hypertension clinic. All subjects underwent regular examinations in our clinic. In addition to basic laboratory and clinical parameters, 24 h ambulatory blood pressure monitoring (ABPM) (Spacelabs) was evaluated. Unplanned blood sampling for assessment of serum antihypertensive drug concentrations by the means of liquid chromatography-mass spectrometry was performed in all patients. In case of spironolactone, its active metabolite canrenone was also evaluated. Total non-compliance was then defined as the absence of all measured antihypertensive drugs. Partial non-compliance was calculated as the absence of serum levels of at least one, but not all antihypertensive drugs prescribed.

RESULTS

Good blood pressure control was detected (mean 24 h systolic/diastolic BP 130 ± 12/77 ± 9 mmHg). The average number of antihypertensive drugs was 3.9 ± 1.5. All subjects were treated by MR antagonists. 44% of patients received spironolactone (average daily dose 45 ± 20 mg) and in the remaining 56% of subjects eplerenone was administered (average daily dose 80 ± 30 mg) due to spironolactone side effects. Assessment of antihypertensive drug concentrations revealed full adherence in 80% of all subjects, partial nonadherence was noted in the remaining 20% of subjects. MR antagonist levels were detected in almost all subjects (49 out of 50).

CONCLUSIONS

Good blood pressure control and adherence to therapy were detected in conservatively treated patients with PA. Eplerenone had to be used quite often as male subjects did not tolerate dose escalation due to spironolactone side effects.