Antihypertensive Medication Adherence and Confirmation of True Refractory Hypertension

A cost-analysis of managing secondary and apparent treatment-resistant hypertension in a specialist multidisciplinary hypertension clinic

OBJECTIVES

A knowledge gap exists around the costs and budget impact of specialist hypertension clinics. This study reports on the cost of providing care in a multidisciplinary hypertension clinic staffed by nephrologist, endocrinologist and cardiologist, which manages patients with suspected secondary hypertension and/or apparent treatment-resistant hypertension. The aim of this study is to provide the evidence required to inform policy and planning care pathways for this patient group.

METHODS

A cost analysis from a healthcare provider perspective using micro-costing techniques was conducted to estimate the direct implementation costs of existing standard practice for the care pathway of patients attending the multidisciplinary hypertension clinic. Sixty-five patients originally recruited for a study of medication adherence in hypertension were included in the sample.

RESULTS

The total care-pathway cost per patient, taking into account clinic visits, clinical reviews, investigations and MDT discussion, was estimated to be €3277, on average. For the patient subgroups, the average cost was €5644 for patients diagnosed with primary aldosteronism and €1446 for patients diagnosed with essential hypertension.

CONCLUSION

There is significant cost associated with providing specialized hypertension care for patients with apparent treatment-resistant hypertension. Given the high rates of nonadherence in this population, it is likely that some of this cost could be avoided with better detection and management of medication adherence in this challenging population. Future studies should consider the cost-effectiveness of this or similar models of care by exploring the benefit to patients and the wider healthcare context of providing care of this type.

Controversies in Hypertension V: Resistant and Refractory Hypertension

Apparent resistant hypertension, defined as uncontrolled office blood pressure despite ≥ 3 antihypertensive medications including a diuretic or use of ≥ 4 medications regardless of blood pressure, occurs in ≤ 15% of treated hypertensives. Apparent refractory hypertension, defined as uncontrolled office pressure despite use of 5 or more medications including a diuretic, occurs in ≤ 10% of resistant cases. Both are associated with increased comorbidity and enhanced cardiovascular risk. To rule out pseudo-resistant or pseudo-refractory hypertension, employ guideline-based methodology for obtaining pressure, maximize the regimen, rule out white-coat effect, and assess adherence. True resistant hypertension is characterized by volume overload and aldosterone excess, refractory by enhanced sympathetic tone. Spironolactone is the preferred agent for resistance, with lower doses. Spironolactone, potassium binders, or both, are preferred if the estimated glomerular filtration rate is below 45. If significant albuminuria, finerenone is indicated. The optimal treatment of refractory hypertension is unclear, but sympathetic inhibition (α-β blockade, centrally acting sympathoinhibitors, or both) seems reasonable. Renal denervation has shown minimal benefit for resistance, but its role in refractory hypertension remains to be defined.

Resistant hypertension: consensus document from the Korean society of hypertension

Although reports vary, the prevalence of true resistant hypertension and apparent treatment-resistant hypertension (aTRH) has been reported to be 10.3% and 14.7%, respectively. As there is a rapid increase in the prevalence of obesity, chronic kidney disease, and diabetes mellitus, factors that are associated with resistant hypertension, the prevalence of resistant hypertension is expected to rise as well. Frequently, patients with aTRH have pseudoresistant hypertension [aTRH due to white-coat uncontrolled hypertension (WUCH), drug underdosing, poor adherence, and inaccurate office blood pressure (BP) measurements]. As the prevalence of WUCH is high among patients with aTRH, the use of out-of-office BP measurements, both ambulatory blood pressure monitoring (ABPM) and home blood pressure monitoring (HBPM), is essential to exclude WUCH. Non-adherence is especially problematic, and methods to assess adherence remain limited and often not clinically feasible. Therefore, the use of HBPM and higher utilization of single-pill fixed-dose combination treatments should be emphasized to improve drug adherence. In addition, primary aldosteronism and symptomatic obstructive sleep apnea are quite common in patients with hypertension and more so in patients with resistant hypertension. Screening for these diseases is essential, as the treatment of these secondary causes may help control BP in patients who are otherwise difficult to treat. Finally, a proper drug regimen combined with lifestyle modifications is essential to control BP in these patients.

Dietary sodium restriction reduces blood pressure in patients with treatment resistant hypertension

PURPOSE

Patients with treatment resistant hypertension (TRH) are at particular risk of cardiovascular disease. Life style modification, including sodium restriction, is an important part of the treatment of these patients. We aimed to analyse if self-performed dietary sodium restriction could be implemented in patients with TRH and to evaluate the effect of this intervention on blood pressure (BP). Moreover, we aimed to examine if mechanisms involving nitric oxide, body water content and BNP, renal function and handling of sodium were involved in the effect on nocturnal and 24-h BP. Also, measurement of erythrocyte sodium sensitivity was included as a possible predictor for the effect of sodium restriction on BP levels.

PATIENTS AND METHODS

TRH patients were included for this interventional four week study: two weeks on usual diet and two weeks on self-performed sodium restricted diet with supplementary handed out sodium-free bread. At the end of each period, 24-h BP and 24-h urine collections (sodium, potassium, ENaC) were performed, blood samples (BNP, NOx, salt blood test) were drawn, and bio impedance measurements were made.

RESULTS

Fifteen patients, 11 males, with a mean age of 59 years were included. After sodium restriction, urinary sodium excretion decreased from 186 (70) to 91 [51] mmol/24-h, and all but one reduced sodium excretion. Nocturnal and 24-h systolic BP were significantly reduced (- 8 and - 10 mmHg, respectively, p < 0.05). NOx increased, BNP and extracellular water content decreased, all significantly. Change in NOx correlated to the change in 24-h systolic BP. BP response after sodium restriction was not related to sodium sensitivity examined by salt blood test.

CONCLUSION

Self-performed dietary sodium restriction was feasible in a population of patients with TRH, and BP was significantly reduced. Increased NOx synthesis may be involved in the BP lowering effect of sodium restriction.

TRIAL REGISTRATION

The study was registered in Clinical trials with ID: NCT06022133.

Therapeutic Drug Monitoring in Arterial Hypertension

(1) Background: This study was planned to assess the concentration of antihypertensive drugs (AHD) in the blood serum in patients with controlled and uncontrolled arterial hypertension (AH). (2) Methods: We assessed 46 patients with AH. Based on the results of 24 h blood pressure monitoring (ABPM), the patients were randomized into two groups. The first group consisted of the patients with controlled AH; the second group consisted of the patients with uncontrolled AH. Venous blood was taken in both groups of patients in the morning before and 2 h after taking drugs to assess the concentration of lisinopril, amlodipine, valsartan, and indapamide. (3) Results. The first group included 27 patients, and the second group 19 patients. In patients with uncontrolled AH, the median concentrations of lisinopril, indapamide, amlodipine, and valsartan before and after taking the drugs did not differ from patients who reached the target BP values. (p > 0.05). In some patients with uncontrolled and controlled (shown for the first time) AH the concentration of AHD was below the limit of quantitative determination. (4) Conclusions. The obtained results indicate that the pharmacokinetics of AHD, apparently, does not play a significant role in the development of ineffectiveness of the ongoing therapy for AH. Therapeutic drug monitoring can be used to test adherence to the treatment.

Structural modification and antihypertensive activity study of formononetin derivatives

A series of formononetin derivatives with substituted benzyloxy groups on the 4' position of isoflavone were designed and synthesized. Their vasodilative activities were evaluated by wire myograph system on isolated rat mesenteric arterial ring. The preliminary SAR of target compounds was thus discussed. Compounds 3d and 3e exhibited potent vasodilative activities against the rat mesenteric arterial rings induced contraction with K⁺. Compounds 3d and 3e also showed antihypertensive effects in SHRs by oral administration.

An Update on Refractory Hypertension

Purpose of Review

To update on definition, diagnosis, prevalence, patient characteristics, pathophysiology, and treatment of refractory hypertension (RfHTN).

Recent Findings

Refractory hypertension (RfHTN) is defined as blood pressure (BP) that is uncontrolled despite using ≥ 5 antihypertensive medications of different classes, including a long-acting thiazide diuretic and a mineralocorticoid receptor antagonist (MRA) at maximal or maximally tolerated doses. This new phenotype is different from resistant hypertension (RHTN), defined as BP that is uncontrolled despite using ≥ 3 medications, commonly a long-acting calcium channel blocker (CCB), a blocker of the renin-angiotensin system (angiotensin-converting enzyme [ACE] inhibitor or angiotensin receptor blocker [ARB]), and a diuretic. The RHTN phenotype includes controlled RHTN, BP that is controlled on 4 or more medications. RfHTN is largely attributable to increased sympathetic activity, unlike RHTN, which is mainly due to increased intravascular fluid volume frequently caused by hyperaldosteronism and chronic excessive sodium ingestion. Compared to those with controlled RHTN, patients with RfHTN have a higher prevalence of target organ damage and do not have elevated aldosterone levels. Ongoing clinical trials are assessing the safety and efficacy of using devices to aid with BP control in patients with RfHTN.

Summary

RfHTN is a separate entity from RHTN and is generally attributable to increased sympathetic activity.

Refractory Hypertension: a Narrative Systematic Review with Emphasis on Prognosis

PURPOSE OF REVIEW

To perform a narrative systematic review on refractory hypertension (RfHT) with particular emphasis on prognosis.

RECENT FINDINGS

There were 37 articles on RfHT, 13 non-systematic reviews, and 24 original studies. RfHT, a recently described extreme phenotype of anti-hypertensive treatment failure, shall be defined as uncontrolled out-of-office blood pressure (BP) levels despite the use of at least 5 anti-hypertensive drugs, including a long-acting diuretic and a mineraloreceptor antagonist. Its prevalence ranges from 0.5 to 4.3% of general treated hypertensives and between 3.6 and 51.4% of patients with resistant hypertension (RHT). RfHT is associated with younger age, African ancestry, obesity, hypertension-mediated organ damage and clinical cardiovascular diseases, and with some comorbidities, such as diabetes and obstructive sleep apnea. Its physiopathological mechanisms probably involve sympathetic overactivity and not volume overload. Patients with RfHT have a worse prognosis than non-refractory RHT individuals, with higher risks of adverse cardiovascular and renal outcomes and of mortality. RfHT represents a rare but true extreme phenotype of anti-hypertensive treatment failure distinct from RHT and with a significantly worse prognosis. Identifying such individuals is important to tailor specific interventions.

The Effect of Depression on Treatment Adherence Among a Sample of Saudi Patients Diagnosed with Acne Vulgaris

Purpose

Acne vulgaris is an inflammatory disorder of the skin and is the most common dermatological disease, affecting all ages and races. Acne is known to be associated with depression. This study aimed to assess the impact of depression on patient adherence to acne vulgaris treatment using The Expectation Confirmation Theory (ECT).

Patients and Methods

This cross-sectional study was conducted with 204 patients with acne using four scales (depression, satisfaction, intention to adhere to acne medication, and control for confirmation). ECT scales were used to assess patient satisfaction and intention to adhere to medication. Demographic data were also collected, and descriptive and analytical statistical analyses were performed.

Results

A total of 204 questionnaires were completed. The mean age of the respondents was 25 ± 7.2. The majority were female; 167 (83.50%). Multiple linear regression analysis indicated a negative association between depression (β= −0.121, p = 0.033; 95% CI, −0.232 to −0.009) and satisfaction, when holding other variables constant, and the expected medication effect (confirmation) had a positive association with satisfaction (β= 0.334, p< 0.001; 95% CI, 0.202 to 0.466), keeping all other factors constant. Male sex was negatively associated with satisfaction (β= −2.388, p= 0.015; 95% CI −4.303 to −0.473), while keeping all other covariate sconstant. Residence in central provinces was a significant predictor of satisfaction (β= 2.562, p= 0.004; 95% CI, 0.832 to 4.292), when holding other factors constant. After conducting a simple linear regression, a positive significant association was found between adherence and satisfaction (β = 0.1713; 95% CI, 0.068 to 0.274).

Conclusion

Adherence is the cornerstone for a successful treatment plan and prevention of relapse or treatment failure, and satisfaction is an essential indicator for improving health policies and implementing social service provisions.

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

[Figure: see text].

Nonadherence to antihypertensive medications amongst patients with uncontrolled hypertension: A retrospective study

ABSTRACT

Medication nonadherence represents a modifiable risk factor for patients with hypertension. Identification of nonadherent patients could have significant clinical and economic implications in the management of uncontrolled hypertension.We analysed the results of 174 urinary adherence screens from patients referred to Addenbrooke's Hospital, Cambridge, for uncontrolled hypertension. Cases were identified for evaluation by results of liquid chromatography-tandem mass spectrometry of urine samples (males: 91; females: 83; age range: 17-87). We performed a binary logistic regression analysis for nonadherence using age, sex, and number of medications prescribed (both antihypertensives and non-antihypertensives separately) as independent predictors. Rates of nonadherence for individual antihypertensive drugs were calculated if prescribed to ≥10 patients.The overall rate of nonadherence to one or more prescribed antihypertensive medications was 40.3%. 14.4% of all patients were nonadherent to all prescribed antihypertensive medications (complete nonadherence), whereas 25.9% of all patients were nonadherent to at least 1, (but not all) prescribed antihypertensive medications (partial nonadherence). 72% of patients were prescribed ≥3 antihypertensives And for every increase in the number of antihypertensive medications prescribed, nonadherence increased with adjusted odds ratios of 2.9 (P < .001). Logistic regression showed that women were 3.3 times more likely to be nonadherent (P = .004). Polypharmacy (≥6 medications prescribed for hypertension and/or concomitant comorbidities) was prevalent in 52%. Bendroflumethiazide and chlortalidone demonstrated the highest and lowest nonadherences respectively (45.5% and 11.8%).Rate of nonadherence in patients with hypertension was significantly impacted by sex and number of antihypertensive medications prescribed. Understanding these factors is crucial in identifying and managing nonadherence.

Interventions that improve adherence to antihypertensive medications in coronary heart disease patients: a systematic review

A systematic review is conducted to identify effective interventions that improved adherence to antihypertensive drugs among patients with coronary heart diseases (CHDs). Primary studies designed to measure interventions to improve adherence on antihypertensive drugs in patients with CHD were included. Three online databases, COCHRANE, EMBASE and MEDLINE, were searched for primary studies published in English from 2005 to 2019. Studies were screened independently for eligibility. Cochrane risk-of-bias tool and the Newcastle-Ottawa Scale were used for quality assessment of randomised controlled trials (RCTs) and non-randomised studies, respectively. Of the 2000 entries identified, seven articles, including one cross-sectional study and six RCTs, met the inclusion criteria and were reviewed. One of the articles evaluated two interventions, so eight interventions were evaluated in total. Quality of the included studies was generally high, with the cross-sectional study rated as having good quality under Newcastle-Ottawa Scale, while four and two RCTs were rated as having low and some risk of bias under Cochrane risk-of-bias tool, respectively. Six of the intervention programmes were considered effective. An intervention was considered effective if it is associated with a significant (p≤0.05) and non-trivial (Cohen's d≥0.2) improvement in compliance-related outcomes such as in terms of the Morisky 8-item Medication Adherence Scale. Medication education, disease education, health education, constant reminders and medications dispensed using blister packs were identified to be effective in improving patients' compliance to medications. The importance of the continuity of interventions was also established. It is recommended that health service institutions should provide continuous education programmes, daily reminders and regular follow-ups for their patients who have CHD. It is recommended that further research ought to be carried out by using only one intervention in each trial with a standardised outcome measure, or using factorial designs, so that further cost-effectiveness evaluation of each intervention can be carried out independently, leading to the formulation of a comprehensive, optimised intervention programme for patients with CHD taking antihypertensives.

Refractory Hypertension and Risks of Adverse Cardiovascular Events and Mortality in Patients With Resistant Hypertension: A Prospective Cohort Study

Background

The long‐term prognosis of refractory hypertension (RfHT), defined as failure to control blood pressure (BP) levels despite an antihypertensive treatment with ≥5 medications including a diuretic and mineraloreceptor antagonist, has never been evaluated.

Methods and Results

In a prospective cohort study with 1576 patients with resistant hypertension, patients were classified as refractory or nonrefractory based on uncontrolled clinic (or office) and ambulatory BPs during the first 2 years of follow‐up. Multivariate Cox analyses examined the associations between the diagnosis of RfHT and the occurrence of total cardiovascular events (CVEs), major adverse CVEs, and cardiovascular and all‐cause mortality, after adjustments for other risk factors. In total, 135 patients (8.6%) had RfHT by uncontrolled ambulatory BPs and 167 (10.6%) by uncontrolled clinic BPs. Over a median Follow‐Up of 8.9 years, 338 total CVEs occurred (288 major adverse CVEs, including 124 myocardial infarctions, and 96 strokes), and 331 patients died, 196 from cardiovascular causes. The diagnosis of RfHT, using either classification by clinic or ambulatory BPs, was associated with significantly higher risks of major adverse CVEs, cardiovascular mortality, and stroke incidence, with hazard ratios varying from 1.54 to 2.14 in relation to patients with resistant nonrefractory hypertension; however, the classification based on ambulatory BPs was better in identifying higher risk patients than the classification based on clinic BP levels.

Conclusions

Patients with RfHT, particularly when defined by uncontrolled ambulatory BP levels, had higher risks of major adverse CVEs and mortality in relation to patients with resistant but nonrefractory hypertension, supporting the concept of refractory hypertension as a true extreme phenotype of antihypertensive treatment failure.

Reserpine Substantially Lowers Blood Pressure in Patients With Refractory Hypertension: A Proof-of-Concept Study

BACKGROUND

Refractory hypertension (RfHTN), a phenotype of antihypertensive treatment failure, is defined as uncontrolled automated office blood pressure (AOBP) ≥130/80 mm Hg and awake ambulatory blood pressure (ABP) ≥130/80 mm Hg on ≥5 antihypertensive medications, including chlorthalidone and a mineralocorticoid receptor antagonist. Previous studies suggest that RfHTN is attributable to heightened sympathetic tone. The current study tested whether reserpine, a potent sympatholytic agent, lowers blood pressure (BP) in patients with RfHTN.

METHODS

Twenty-one out of 45 consecutive patients with suspected RfHTN were determined to be fully adherent with their antihypertensive regimen. Seven patients agreed to participate in the current clinical trial with reserpine and 6 patients completed the study. Other sympatholytic medications, such as clonidine or guanfacine, were tapered and discontinued before starting reserpine. Reserpine 0.1 mg daily was administered in an open-label fashion for 4 weeks. All patients were evaluated by AOBP and 24-hour ABP at baseline and after 4 weeks of treatment.

RESULTS

Reserpine lowered mean systolic and diastolic AOBP by 29.3 ± 22.2 and 22.0 ± 15.8 mm Hg, respectively. Mean 24-hour systolic and diastolic ABPs were reduced by 21.8 ± 13.4 and 15.3 ± 9.6 mm Hg, mean awake systolic and diastolic ABPs by 23.8 ± 11.8 and 17.8 ± 9.2 mm Hg, and mean asleep systolic and diastolic ABPs by 21.5 ± 11.4 and 13.7 ± 6.4 mm Hg, respectively.

CONCLUSIONS

Reserpine, a potent sympatholytic agent, lowers BP in patients whose BP remained uncontrolled on maximal antihypertensive therapy, lending support to the hypothesis that excess sympathetic output contributes importantly to the development of RfHTN.