The Prevalence of Japanese Outpatients with Hypertension Who Meet the Definition of Treatment Resistant Hypertension and Are Eligible for Enrolment in Clinical Trials of Endovascular Ultrasound Renal Denervation

Objective A clinical trial (REQUIRE) was started to investigate the use of an ultrasound renal denervation system in the treatment of resistant hypertension (RHT). We analyzed the prevalence of patients who were eligible for inclusion in this cross-sectional study at the time of screening. Methods Nine-hundred ninety-nine consecutive hypertension (HT) patients who were treated in our hospital as outpatients were classified into the following categories: patients treated with at least 3 types of antihypertensive drugs including diuretic agents who were eligible for enrolment in SYMPLICITY HTN-Japan (SH-J) with an office systolic blood pressure (SBP) of ≥160 mmHg, who were ≤80 years of age, and an estimated glomerular filtration rate (eGFR) of ≥45 mL/min/1.73 m2 (RHT-S); and patients who were treated similar medications and who were eligible for enrolment in REQUIRE, with an SBP of ≥150 mmHg, ≤75 years of age, and an eGFR of ≥40 mL/min/1.73 m2 (RHT-R). We investigated the proportion of patients in each category. We also investigated HT patients (1,423 cases) who were enrolled in the Chikushi Anti-Hypertension Trial (CHAT), a research network that includes general practitioners. Results Eleven patients (1.1%) with RHT-S and 18 patients (1.8%) with RHT-R were identified. After the exclusion of patients with secondary HT and a diastolic blood pressure (DBP) of <90 mmHg (applied in REQUIRE), 5 patients (0.5%) with RHT-S and 4 patients (0.4%) with RHT-R remained. In the analysis of the CHAT study, only 2 (0.1%) patients with RHT-R remained. Conclusion The number of eligible patients in the REQUIRE trial was decreased, largely due to the strict age restriction and the new DBP limitation. The prevalence of eligible patients in REQUIRE was estimated to be approximately 0.5 to 0.8 times that in SH-J. Since patient enrollment will be difficult, drastic measures may be required to recruit eligible patients.