Patient Preference for Catheter-Based Hypertension Therapy and Subgroup Analysis: A Pilot Study Based on Taiwan Consensus on Renal Denervation

Abstract

Ojective

To understand hypertensive patients’ preference for catheter-based therapy to manage hypertension.

Methods

Survey data regarding catheter-based therapies performed at MacKay Memorial Hospital in Taipei, Taiwan, between 2019-2020 were analyzed. The questionnaire was circulated either in the clinics or during admission. A total of 46 patients completed the questionnaire.

Results

A total of 46 patients (mean age 53.4 ± 13.5 years, 78.3% male) completed the questionnaire. In subgroup analysis according to Taiwan renal denervation (RDN) consensus, patients with drug intolerance (61.8% vs. 31.3%, p = 0.02) were more likely to choose RDN. Moreover, although lacking statistical significance, it is noteworthy that numerically more of the resistant hypertension group (55.6% vs. 28.0%, p = 0.09) and non-adherence group (38.5% vs. 30.0%, p = 0.20) were willing to undergo RDN. Conversely, numerically fewer patients with hypertension-mediated organ damage accepted RDN compared to those who did not have hypertension-mediated organ damage (26.1% vs. 43.5%, p = 0.21), although this disparity did not reach statistical significance.

Conclusions

Approximately one-third of the patients expressed interest in considering RDN in this study. The most influential factor in patients’ preference for RDN was drug intolerance due to medication-related side effects.

Abbreviations

BP, Blood pressure

RDN, Renal denervation

BACKGROUND

Affecting 5 million people in Taiwan and over 1 billion worldwide, hypertension remains the major preventable and easily identifiable risk factor for cardiovascular disease, including myocardial infarction, stroke, heart failure, atrial fibrillation, aortic dissection, and peripheral arterial disease.¹ According to recent statistics, fewer than 50% of patients achieve hypertension control in economically developed and developing countries.² For some patients who have difficulty in blood pressure (BP) control using contemporary methods, catheter-based hypertension control therapy such as renal denervation (RDN) could be a valuable additive or alternative treatment option.^3,4 RDN has proven to be an attractive and effective option for patients with hypertension who cannot achieve adequate BP goals with pharmacological antihypertensive strategies, and those who have elevated cardiovascular risk, poor adherence to treatment regimens, or other factors.^5-8

The Taiwan RDN consensus recommends that several subgroups of hypertensive patients are candidates for RDN, termed "RDNi2": resistant hypertension, hypertension-mediated organ damage, non-adherence, and drug intolerance.⁴ On the other hand, patient preference examines how patients evaluate the treatment decision-making process. It plays an important role in shared decision-making between patients and physicians, and has become widely emphasized contemporarily.^9,10 There is also new evidence showing that RDN is more effective in selected patients.¹¹ However, the patient’s opinion regarding treatment options may significantly vary from that of their physicians.

RDN represents a relatively new strategy for managing hypertension; however, patient perceptions of RDN have not been adequately studied in Taiwan. Therefore, in this study, we surveyed patients at MacKay Memorial Hospital in Taipei, Taiwan, and explored their points of view about RDN.

METHODS

Objectives

This study aimed to understand patients’ preference and attitude toward treating hypertension with RDN. Data were retrospectively analyzed from 46 responses to a questionnaire circulated among patients at Taipei and Tamsui MacKay Memorial Hospital between 2019 and 2020.

The questionnaire was designed to determine how the patients would decide whether they accepted a catheter-based procedure in addition to taking medications. Data on clinical characteristics, BP measurements, medication category and pill numbers, complications of current treatments, drug adherence, and treatment preferences were collected and analyzed. Patient preferences were compared among different patient subgroups, including resistance hypertension, organ damage, non-adherence, and drug intolerance.

Participants

We surveyed people diagnosed with hypertension who were either treated or untreated with antihypertensive medications who resided in Taipei City and New Taipei City. Ethics approval was obtained from the appropriate bodies in each region. The identity of the responders was not disclosed at any point.

Study endpoints

Patient data included: time since diagnosis, BP level, duration of antihypertensive medication, self-reported degree of adherence, number of current medications, concomitant medical conditions, side effects, knowledge of hypertension and associated risks, willingness to consider RDN, and reasons for accepting or rejecting RDN.

Definition of determinants

In our questionnaire, non-adherence was defined as being "positive" under the following circumstances: forgetting to take the prescribed medication, expressing a lack of perceived necessity for taking the medication, choosing to skip taking the medication to reduce medical expenses, and encountering challenges in maintaining the medication schedule during travel. Non-adherence was defined as being "negative" when the patients self-reported never missing a dose of any antihypertensive. Drug intolerance was defined as being "positive" if the patients self-reported any adverse effect of BP-lowering drugs, such as dry cough, edema, asthenia, or erectile dysfunction.

Organ damage was determined through a review of medical records. If the patient had hypertensive-related diseases such as coronary artery disease, heart failure, atrial fibrillation, acute coronary syndrome, stroke/transient ischemic attack, abnormal kidney function (estimated glomerular filtration rate < 60), and peripheral arterial disease, the presence of organ damage was recorded as being positive.

Statistical methods

Data were descriptively analyzed. Categorical variables were presented as frequencies and percentages. The mean and standard deviation were used to represent continuous variables. Whenever appropriate, the chi-squared test for two population proportions was used to compare categorical variables, and continuous variables were compared using unpaired t-tests. Statistical significance was defined as a two-sided p value less than 0.05.

RESULTS

Baseline characteristics

A total of 46 patients (mean age 53.4 ± 13.5 years, 78.3% male) completed the questionnaire survey between 2019 and 2020. Despite consuming multiple anti-hypertensive medications, most of the patients had high BP (Table 1). More than half of the patients had a less than 10-year history of hypertension, with 72% reporting less than 10 years since the diagnosis. Over half (58.7%) of the patients had cardiovascular comorbidities. The self-reported adherence rate was 63%, and the respondents considered themselves to be always adherent to their medication regimens, regardless of the side effects and challenging treatment schedules.

Table 1. Baseline characteristics of enrolled patients (n = 46).

Characteristics	Patient numbers (%)
Age, years	53.4 ± 13.0
≤ 50	14 (30)
51-70	28 (61)
≥ 70	4 (9)
Systolic blood pressure, mmHg	136.6 ± 16.9
≤ 130	12 (26)
131-150	25 (54)
≥ 150	9 (20)
Duration of hypertension, years	6.3 ± 1.5
≤ 10	33 (72)
10-20	8 (17)
≥ 20	5 (11)
Number of pills taken for hypertension per day	2.3 ± 1.2
0	5 (11)
1	4 (9)
2	17 (36)
3	11 (24)
≥ 4	9 (20)
Self-reported adherence
Never or sometimes	5 (11)
Usually	12 (26)
Always	25 (63)
Comorbidity presents	27 (58.7)

The mean duration of hypertension was 6.3 ± 1.5 years, with an average BP of 136.6/80.5 mmHg. Nearly 50% of the patients were complicated with organ damage, and 65% experience drug intolerance.

Patient preference: subgroup analysis based on Taiwan RDN consensus "RDNi2"

Among the 46 investigated patients, about one-third expressed a preference for RDN (16/46, 34.8%) (Figure 1). Notably, all patients (100%) relied on their physician as the primary source of information and had previously encountered side effects from antihypertensive medications.

Figure 1.

Percentage of Con-RDN and Pro-RDN. BP, blood pressure; RDN, renal denervation.

Certain patient characteristics were more frequently associated with a greater willingness to consider RDN. Patients diagnosed with drug intolerance were most willing to opt for RDN over pharmacotherapy (68.8% vs. 31.3%, p = 0.02), and would consider a one-time intervention for their high BP (Figure 2). The patients who had resistant hypertension (55.6% vs. 28.0%, p = 0.09) and drug non-adherence (38.5% vs. 30.0%, p = 0.20) showed a numerically stronger preference for RDN. On the other hand, a comparison of patients with and without end-organ damage found that numerically fewer patients with end-organ damage were willing to consider RDN over drug treatment (26.1% vs. 43.5%, p = 0.21). A physician’s recommendation was an important factor positively influencing the patients’ readiness to undergo RDN. The effect of reduced BP after the intervention was an additional driver of acceptance. Approximately one-fifth of those asked were influenced by the experiences of other patients who had undergone the procedure. If the procedure could reduce the number of medications taken as well as the BP variability, 100% and 98.3% of the patients would prefer RDN, respectively. Seventy percent of the patients expected a reduction of more than one pill per day.

Figure 2.

Subgroup analysis for patient preference. RDN, renal denervation.

DISCUSSION

This article is the first in Taiwan to explore patients’ preferences for RDN. With the emergence of catheter intervention techniques, RDN has become an acceptable strategy for lowering blood pressure. We found that the patients who were intolerant to the side effects of antihypertensives or wanted to reduce the number of daily drugs were more likely to choose RDN. Additionally, highlighting the benefits of RDN in allowing the patients to avoid medication side effects or potentially decrease the number of required medications, could significantly enhance their motivation to manage their blood pressure. A previous study⁹ suggested that physician recommendations are the single most deterministic factor among patients likely to consider catheter-based RDN. However, in our study, the primary consideration for choosing RDN was the expectation that the procedure could reduce the number of medications taken.

Radiofrequency RDN was first introduced in Taiwan in 2013. Hence, it is not surprising that the patients’ main concerns surrounded the interventional nature of the procedure. The irreversibility of an ablation procedure contrasts with that of medications, which can be discontinued in cases of unacceptable efficacy or tolerability. However, as in a previous study,⁹ our data also suggested that only a few patients saw this as an issue with an interventional procedure. Some patients were concerned about the necessity of continuing with pills post-RDN.

Financial issues played a significant role in our study. Whether the cost of the procedure was covered by health insurance, and whether the procedure could reduce the cost of medications influenced the attitudes toward treatment.

It appears that our patients, regardless of their current blood pressure levels and pill count, were equally receptive to RDN. Given its favorable safety profile, a discussion is currently ongoing in Europe regarding the most suitable target population for RDN. Understanding patients’ opinions will enable the more efficient use of clinical resources and improve the feasibility of opting for the most suitable treatment for individual patients.

The uniqueness of this report lies in categorizing and analyzing these 46 patients based on "RDNi2". A key limitation of this study is the relatively small study sample size. Although the preference was statistically insignificant in patients with resistant hypertension, the numerical difference deserves further investigation in a larger study population.

CONCLUSIONS

Our findings revealed that approximately one-third of hypertensive patients opted for RDN. Among the RDNi2 subgroups, drug intolerance was the most significant deterministic factor behind patients choosing RDN. In conclusion, it is essential to understand patient preference in order to achieve shared decision-making and improve hypertension control and management.

DECLARATION OF CONFLICT OF INTEREST

All the authors declare no conflict of interest.