Antihypertensive drug concentration measurement combined with personalized feedback in resistant hypertension: a randomized controlled trial

Quality-of-life and beliefs about medication in relation to a therapy adherence intervention in resistant hypertension: the Resistant HYpertension: MEasure to ReaCh Targets trial

OBJECTIVE

To assess the impact of personalized feedback on therapy adherence testing results on quality of life and beliefs about medication in patients with resistant hypertension, as well as to identify patient-oriented predictors of therapy adherence.

METHODS

This study was a prespecified post hoc analysis of the multicenter randomized controlled trial Resistant HYpertension: MEasure to ReaCh Targets (RHYME-RCT). Patients were randomized to a personalized feedback conversation on measured antihypertensive drug levels additional to standard-of-care, or standard-of-care only. The primary outcomes consisted of EuroQol EQ-5D-5L and Beliefs about Medicine Questionnaire (BMQ) scores at 12 months.

RESULTS

A total of 56 patients with median age 61.5 [25th-75th percentile: 55.8-69.3] years (21.4% women) were included. Mean blood pressure ±SD was 149.8/84.1 ± 14.9/13.8 mmHg while being on a median of 5.6 [4.8-7.3] defined daily dosages (DDD) of antihypertensive drugs. At 12 months, no differences were observed in EQ-5D-5L index (0.81 [0.69-0.89] vs. 0.89 [0.73-1.00]; P  = 0.18) and visual analogue scale score on general patient-perceived health (70 [60-80] vs. 70 [60-82]; P  = 0.53) between the intervention-arm and the standard-of-care only-arm. Likewise, individual EQ-5D-5L domain scores and BMQ scores did not differ between both arms. Irrespective of the intervention, independent positive predictors of the percentage adherence were patient age, EQ-5D-5L index score, BMQ-specific necessity score and concern score, whereas the total number of drugs prescribed was a negative predictor.

CONCLUSION

Within this prespecified subanalysis of the randomized RHYME-RCT trial, implementation of a personalized feedback conversation targeting therapy adherence did not improve health-related quality-of-life and beliefs about medication in patients with resistant hypertension.

'Under pressure': The role of therapeutic drug monitoring in the treatment of hypertension

Antihypertensive drugs do not qualify as optimal candidates for therapeutic drug monitoring (TDM), given their obvious physiological effect, the absence of a clear relationship between drug concentrations and pharmacodynamic outcomes and their wide therapeutic range. However, since non-adherence is a major challenge in hypertension management, using drug concentrations can be of value to identify non-adherence as a first step towards better blood pressure control. In this article we discuss the key challenges associated with measuring and interpreting antihypertensive drug concentrations that are important when TDM is used to improve non-adherence. Additionally, we elaborate on the role of TDM in optimizing antihypertensive drug treatment besides addressing non-adherence by highlighting its value in specific patient groups with altered pharmacokinetic parameters such as female vs. male or elderly patients.

Improvement of non-adherence and reduction of BP values in patients with difficult-to-treat hypertension: the ATHAN clinical trial

Hypertension treatment and blood pressure (BP) control reduce cardiovascular disease burden. However, prevalence of controlled BP is overall insufficient and lack of adherence to treatment is a suggested major contributor. This prospective, randomized clinical trial was designed to evaluate whether a specific 3-month (m) action plan to improve therapeutic adherence results in a decrease in BP. Patients with ambulatory 24 h-BP ≥ 130/80 mmHg despite receiving ≥2 antihypertensive drugs and with therapeutic non-compliance confirmed by antihypertensive drugs analyzed in urine were randomized (1:1) to receive a specific 3 m program to improve adherence (INT = intervention) or routine follow-up (C = control). Antihypertensive treatment was not modified and knowledge of non-adherence was only notified to patients randomized to the intervention group. Before randomization and at 3 m all patients underwent urinary screening for antihypertensive drugs and 24 h-ambulatory-BP monitoring. Forty-five patients (36% women, mean age: 58 ± 13 yr) were randomized. At 3 m, mean (95% CI) BP differences (INT vs. C) were 12.2 mmHg (4.3-20.8), adjusted-p = 0.032 and 8.7 mmHg (2.5-14.8), adjusted-p = 0.018 for 24 h-systolic and 24 h-diastolic BP, respectively. Differences (INT vs. C) for office SBP and DBP were 18.4 mmHg (6.8-30.1), adjusted-p = 0.005 and 15.7 mmHg (7.2-24.2), adjusted-p < 0.001. Non-detected antihypertensive drugs were median [IQR]: 40% [25-100] and 0% [0-20] at baseline and 3 m, respectively, in the INT group, and 33.3% [25-63.7] and 33.3% [23.8-57.9], in the C group (p < 0.001 for the 3-month between-group comparison). A combined action plan of notifying knowledge of non-adherence plus a 3-month specific nursing intervention to improve therapeutic adherence results in BP reduction in patients with inadequate therapeutic compliance.

Physician and patient adherence in hypertension trials: a point of view on an important issue to resolve

INTRODUCTION

Randomized controlled trials (RCTs) are important sources of evidence that strongly influence guidelines for patient management, including for elevated blood pressure in adults.

AREAS COVERED

Critical questions regarding the interpretation of hypertension trial results have recently increased, especially for concerns over methodology. In particular, investigator adherence to the protocol and patient adherence to investigational drugs are often far from optimal. These issues may be ignored or underreported because physicians' behavior during trials is often not monitored and patients' medication adherence is neither measured adequately nor reported or analyzed in the final report or in the publication. This situation may lead to misinterpretations of study results and misevaluations of the safety and efficacy profile of new drugs. In this short review, the problem of measuring, reporting, and analyzing drug adherence in RCTs is discussed and illustrated with several examples in the field of hypertension.

EXPERT OPINION

The main conclusion is that drug adherence should always be measured in clinical trials, possibly with more than one method. In addition, prespecified analyses of adherence data should be included in the statistical plan of all trials to improve their overall quality.

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.

Lessons learned from conducting a randomized controlled trial to improve non-adherence to antihypertensive drug treatment

PURPOSE

Hypertension significantly contributes to cardiovascular diseases and premature deaths. Effective treatment is crucial to reduce cardiovascular risks, but poor adherence to antihypertensive drugs is a major issue. Numerous studies attempted to investigate interventions for identifying non-adherence, but often failed to address the issue effectively. The RHYME-RCT trial sought to bridge this gap by measuring non-adherence by determining antihypertensive drug concentrations in blood through a dried blood spot (DBS) method in patients with resistant hypertension. This measurement was followed by personalized feedback to improve adherence. During the course of this trial several challenges emerged, including selection bias, the gatekeeper role of physicians, the Hawthorne effect and the role of randomization.

AIM

This communication aims to inform fellow researchers and clinicians of challenges that can arise when conducting clinical trials to improve adherence and offer insights for refining study designs to avoid these issues in forthcoming adherence studies.