A case of primary aldosteronism with excessive secretion of renin that was unmasked by kidney transplantation.

A 42-year-old man showed marked hypokalemia after kidney transplantation. He was diagnosed with hypertension and suffered from acute myocardial infarction at 33 and 38 years of age. At 40 years of age, hemodialysis was introduced. A left adrenal tumor was noted and suspected as a non-functional adrenal adenoma at that time. Therefore, he received a living-donor kidney transplant at 42 years of age. After kidney transplantation, the serum creatinine level dropped. His blood pressure remained high, and the serum potassium level decreased. The PRA and PAC were elevated, and ARR was not elevated. Based on the results of various confirmatory tests and vein sampling, he was diagnosed with excessive secretion of renin from the native kidneys that was complicated by primary aldosteronism (PA), and left nephrectomy and adrenalectomy were performed. The overproduction of aldosterone in the resected adrenal adenoma and over secretion of renin in the kidney with arteriolosclerosis were immunohistologically confirmed. After surgery, the PAC decreased, but the PRA did not decrease. The postoperative serum potassium level improved, and the blood pressure was well controlled with a small dose of medication. This is the first reported case of PA with hyperreninemia after kidney transplantation. It should be noted that PA in dialysis patients and kidney transplant recipients may not fulfill the usual diagnostic criteria of an elevated ARR. In such patients, PA should be suspected based on the absolute value of the PAC and responsiveness to ACTH stimulation, and adrenal and renal vein sampling is required for a definitive diagnosis.

Adrenomedullin for biologic-resistant Crohn's disease: A randomized, double-blind, placebo-controlled phase 2a clinical trial.

BACKGROUND AND AIM: Adrenomedullin is a bioactive peptide with many pleiotropic effects, including mucosal healing and immunomodulation. Adrenomedullin has shown beneficial effects in rodent models of inflammatory bowel disease and, more importantly, in clinical trials including patients with ulcerative colitis. We performed a successive clinical trial to investigate the efficacy and safety of adrenomedullin in patients with Crohn's disease (CD). METHODS: This was a multicenter, double-blind, placebo-controlled phase 2a trial that evaluated 24 patients with biologic-resistant CD in Japan. Patients were randomly assigned to three groups and were given an infusion of 10 or 15 ng/kg/min of adrenomedullin or placebo for 8 h per day for 7 days. The primary endpoint was the change in the CD activity index (CDAI) at 8 weeks. The main secondary endpoints included changes in CDAI from week 4 to week 24. RESULTS: No differences in the primary or secondary endpoints were observed between the three groups by the 8th week. Changes in CDAI in the placebo group gradually decreased and disappeared at 24 weeks, but those in the adrenomedullin-treated groups (10 or 15 ng/kg/min group) remained at steady levels for 24 weeks. Therefore, a significant difference was observed between the placebo and adrenomedullin-treated groups at 24 weeks (P = 0.043) in the mixed-effects model. We noted mild adverse events caused by the vasodilatory effect of adrenomedullin. CONCLUSION: In this trial, we observed a long-lasting (24 weeks) decrease in CDAI in the adrenomedullin-treated groups. Adrenomedullin might be beneficial for biologic-resistant CD, but further research is needed.

Adrenomedullin Therapy in Moderate to Severe COVID-19.

The 2019 coronavirus (COVID-19) pandemic is still in progress, and a significant number of patients have presented with severe illness. Recently introduced vaccines, antiviral medicines, and antibody formulations can suppress COVID-19 symptoms and decrease the number of patients exhibiting severe disease. However, complete avoidance of severe COVID-19 has not been achieved, and more importantly, there are insufficient methods to treat it. Adrenomedullin (AM) is an endogenous peptide that maintains vascular tone and endothelial barrier function. The AM plasma level is markedly increased during severe inflammatory disorders, such as sepsis, pneumonia, and COVID-19, and is associated with the severity of inflammation and its prognosis. In this study, exogenous AM administration reduced inflammation and related organ damage in rodent models. The results of this study strongly suggest that AM could be an alternative therapy in severe inflammation disorders, including COVID-19. We have previously developed an AM formulation to treat inflammatory bowel disease and are currently conducting an investigator-initiated phase 2a trial for moderate to severe COVID-19 using the same formulation. This review presents the basal AM information and the most recent translational AM/COVID-19 study.

Translational studies of adrenomedullin and related peptides regarding cardiovascular diseases.

Adrenomedullin (AM) is a vasodilative peptide with various physiological functions, including the maintenance of vascular tone and endothelial barrier function. AM levels are markedly increased during severe inflammation, such as that associated with sepsis; thus, AM is expected to be a useful clinical marker and therapeutic agent for inflammation. However, as the increase in AM levels in cardiovascular diseases (CVDs) is relatively low compared to that in infectious diseases, the value of AM as a marker of CVDs seems to be less important. Limitations pertaining to the administrative route and short half-life of AM in the bloodstream (<30 min) restrict the therapeutic applications of AM for CVDs. In early human studies, various applications of AM for CVDs were attempted, including for heart failure, myocardial infarction, pulmonary hypertension, and peripheral artery disease; however, none achieved success. We have developed AM as a therapeutic agent for inflammatory bowel disease in which the vasodilatory effect of AM is minimized. A clinical trial evaluating this AM formulation for acute cerebral infarction is ongoing. We have also developed AM derivatives that exhibit a longer half-life and less vasodilative activity. These AM derivatives can be administered by subcutaneous injection at long-term intervals. Accordingly, these derivatives will reduce the inconvenience in use compared to that for native AM and expand the possible applications of AM for treating CVDs. In this review, we present the latest translational status of AM and its derivatives.

Adrenomedullin: A Novel Therapeutic for the Treatment of Inflammatory Bowel Disease.

Adrenomedullin (AM) is a bioactive peptide with various physiological functions, including vasodilation, angiogenesis, anti-inflammation, organ protection, and tissue repair. AM suppresses inflammatory cytokine production in the intestinal mucosa, improves vascular and lymphatic regeneration and function, mucosal epithelial repair, and immune function in the intestinal bacteria of animal models with intestinal inflammation. We have been promoting translational research to develop novel therapeutic agents for inflammatory bowel disease (IBD) using AM and have started clinical research for IBD patients since 2010. A multicenter clinical trial is currently underway in Japan for patients with refractory ulcerative colitis and Crohn's disease. Moreover, since current AM administration is limited to continuous intravenous infusion, the development of a subcutaneous formulation using long-acting AM is underway for outpatient treatment.

Study Protocol for a Randomized, Double-Blind, Placebo-Controlled, Phase-II Trial: AdrenoMedullin for Ischemic Stroke Study.

OBJECTIVES: Adrenomedullin (AM), a vasoactive peptide, has strong anti-inflammatory and angiogenic properties, which have been reported to ameliorate the consequences of ischemic stroke in several animal models. After a phase I study in healthy volunteers, two phase II trials of AM for inflammatory bowel diseases have been recently completed. The current AdrenoMedullin For Ischemic Stroke (AMFIS) study aims to assess the safety and efficacy of AM in patients with acute ischemic stroke. MATERIALS AND METHODS: The AMFIS study is an investigator-initiated, randomized, double-blind, phase-II trial. AM or placebo will be administered to patients with non-cardioembolic ischemic stroke within 24 h after stroke onset. In the first cohort of the AMFIS study, patients will be randomly allocated to the investigation treatment A (30 µg/kg of AM in total for 7 days, n = 20) or placebo group (n = 10). In the second cohort, patients will be assigned to the investigation treatment B (56 µg/kg of AM in total for 7 days, n = 20) or placebo group (n = 10). RESULTS: Serious adverse events related to the protocol treatment will be evaluated as the primary outcome. All adverse events will be analyzed as the secondary outcome. Regarding efficacy endpoints, the change in National Institutes of Health Stroke Scale and modified Rankin Scale scores will be compared between investigation treatment and placebo groups. CONCLUSIONS: AM is expected to be a safe and effective treatment for ischemic stroke.

Adrenomedullin for steroid-resistant ulcerative colitis: a randomized, double-blind, placebo-controlled phase-2a clinical trial.

BACKGROUND: Adrenomedullin (AM) is a bioactive peptide having many pleiotropic effects, including mucosal healing and immunomodulation. AM has shown beneficial effects in rodent models and in preliminary study for patients with ulcerative colitis (UC). We performed a clinical trial to investigate the efficacy and safety of AM in patients with UC. METHODS: This was a multi-center, double-blind, placebo-controlled phase-2a trial evaluating 28 patients in Japan with steroid-resistant UC. Patients were randomly assigned to four groups and given an infusion of 5, 10, 15 ng/kg/min of AM or placebo for 8 h per day for 14 days. The primary endpoint was the change in Mayo scores at 2 weeks. Main secondary endpoints included the change in Mayo scores and the rate of clinical remission at 8 weeks, defined as a Mayo score 0. RESULTS: No differences in the primary or secondary endpoints were observed among the four groups at 2 weeks. Despite the insufficient tracking rate, the Mayo score at 8 weeks was only significantly decreased in the high-dose AM group (15 ng/kg/min) compared with the placebo group (- 9.3 ± 1.2 vs. - 3.0 ± 2.8, P = 0.035), with its rate of clinical remission at 8 weeks being significantly higher (3/3, 100% vs. 0/2, 0%, P = 0.025). We noted mild but no serious adverse events caused by the vasodilatory effect of AM. CONCLUSIONS: In this double-blind randomized trial, we observed the complete remission at 8 weeks in patients with steroid-resistant UC receiving a high dose of AM. CLINICAL TRIAL REGISTRY: JAPIC clinical trials information; Japic CTI-205255 (200410115290). https://www.clinicaltrials.jp/cti-user/trial/Search.jsp .

Safety, Tolerability, and Pharmacokinetics of Adrenomedullin in Healthy Males: A Randomized, Double-Blind, Phase 1 Clinical Trial.

BACKGROUND: Adrenomedullin (AM), an endogenous vasodilative peptide, has immunomodulative effects and acts as an accelerator of mucosal regeneration in the digestive tract. AM has shown beneficial effects in rodent models of inflammatory bowel disease and patients with ulcerative colitis. The present study aimed to evaluate the pharmacodynamic properties and safety of AM in healthy male adults in a phase 1 clinical trial. METHODS: This phase 1, randomized, double-blind, single-center study was conducted on healthy males aged 20-65 years. Subjects received either a placebo, 3 ng/kg/min AM, 9 ng/kg/min AM, or 15 ng/kg/min AM via continuous 12-h intravenous infusion. Other subjects received either placebo or 15 ng/kg/min AM for 8 h per day for 7 days. Adverse events (AEs), vital signs, physical examinations, laboratory tests, electrocardiograms (ECG), and pharmacokinetics were assessed. FINDINGS: All 24 subjects in the single-dose test completed the study. Of the 12 subjects in multiple dosing test, one from the AM group withdrew owing to a headache. No serious AEs were reported. Hemodynamic parameters were well maintained in all subjects. Slight ECG abnormalities were observed in the single-dose test. The plasma concentration of AM progressively increased in a dose-dependent manner and reached Cmax at the end of administration. Plasma AM rapidly returned to baseline concentrations after termination, with a T1/2 of under 60 min. INTERPRETATION: This is the first phase 1 trial in healthy men evaluating the safety of AM. Our results demonstrate the safety and tolerability of AM for subsequent Phase 2 trials.

Adrenomedullin: A Novel Therapy for Intractable Crohn's Disease with a Loss of Response to Infliximab.

A 35-year-old man with refractory Crohn's disease showed a loss of response to infliximab after requiring treatment with infliximab at 10 mg/kg together with steroid to maintain remission. His symptoms recurred, and colonoscopy showed extensive active ulcers in the colon. Adrenomedullin therapy was started in addition to the conventional infliximab therapy. A few days after, his symptoms went into remission. Endoscopy at 2 and 7 weeks revealed significant mucosal remission without steroid therapy. Adrenomedullin promoted mucosal healing and led to the re-induction of remission in Crohn's disease in a patient with a loss of response to infliximab.

Efficient screening of patients with aldosterone-producing adenoma using the ACTH stimulation test.

Adrenal venous sampling (AVS) is the gold standard test for distinguishing between unilateral and bilateral primary aldosteronism (PA); however, AVS requires advanced and time consuming technique. The needs for AVS have been increasing due to the increased utilization of screening for PA. An efficient selection of unilateral PA, such as aldosterone-producing adenoma (APA), before AVS is useful to avoid undesirable AVS in bilateral PA, such as idiopathic hyperaldosteronism. In this study, 40 patients who received all three confirmatory tests, including the captopril challenge test, furosemide upright test and adrenocorticotropin (ACTH) stimulation test (AST), and who were diagnosed as having PA by AVS were recruited. Subjects were diagnosed as having unilateral aldosterone excess (n = 22) or bilateral aldosterone excess (n = 18) by AVS. All patients with unilateral PA underwent an operation and were finally diagnosed with APA. Major differences were detected in serum potassium level, basal plasma aldosterone concentration (PAC), presence of adrenal tumor, and AST results between the two groups. The PAC/cortisol ratio at 120 min in the AST showed the highest diagnostic capability for distinguishing the subtypes of PA according to a receiver operating characteristic (ROC) curve analysis (area under the ROC curve was 0.956). At a cutoff value of 1.20 for the PAC/cortisol ratio at 120 min on the AST, the sensitivity was 95.5%, and the specificity was 88.9%. This sufficiently high sensitivity suggests that the PAC/cortisol ratio at 120 min in the AST could be useful for the screening of patients with PA who are suitable for AVS.

Seasonal variation of novel arterial stiffness indexes in Japanese hypertensive patients.

Background and Objective: Seasonal variation of blood pressure (BP) is well known, and a relationship between increases in BP and the incidence of cardiovascular accidents (CVAs) in the winter has been reported. Parameters of arterial stiffness may exhibit seasonal variation; however, available data are currently limited. Novel arterial stiffness indexes, namely the arterial velocity pulse index (AVI) and arterial pressure-volume index (API), can be determined through usual maneuver for BP measurement during the regular examination in the outpatient clinic.The present study assessed the seasonal variation of AVI and API in 59 hypertensive patients undergoing stable treatment and regularly visiting our outpatient clinic over a period of 30 months. Methods: BP, pulse rate (PR), AVI, and API were measured using the AVE-1500 (Pasesa) in the sitting position. Six time frames of assessment were established. All measurements (average: 17.9 measurements per person) were sorted using these six time frames, and their averages were used for analysis. Results: Significant seasonal variations in PR (P < 0.001) and AVI (P < 0.001), along with weak variation in systolic BP (SBP) (P = 0.047) and marginal variation in API (P = 0.055), were confirmed by repeated analysis of variance. SBP, API, and PR were decreased, whereas AVI was increased in the summer. Coefficient variations were SBP 5.1%, PR 4.9%, AVI 12.6%, and API 10.6%. Conclusion: AVI was associated with reflected wave like as augmentation index. Thus, a high AVI may suggest increased central wave reflection. Although the significance of seasonal variation of AVI remains unknown, AVI may influence seasonal variations in the incidence of CVA.

Adrenomedullin Therapy in Patients with Refractory Ulcerative Colitis: A Case Series.

BACKGROUND AND AIMS: Adrenomedullin (AM) is a multifunctional biologically active peptide that has an ameliorative effect against inflammatory bowel disease in several experimental models. We reported the first case where AM infusion dramatically improved symptoms and colonoscopy findings in patients with refractory ulcerative colitis (UC). To confirm the reproducibility of the efficacy and safety of AM infusion, this pilot study evaluated the clinical feasibility of intravenous administration of AM in patients with refractory UC. METHODS: Seven patients with active refractory UC participated and received intravenous infusion of AM (1.5 pmol/kg/min) for 8 h daily for 14 days, and their Disease Activity Index (DAI) were evaluated before and 2 and 12 weeks after beginning AM administration. RESULTS: DAI were improved in all patients after AM administration. Within 2 weeks, marked declines in DAI (≥ 3 points and ≥ 30%) were observed in six patients (85.7%), while a more modest decline was observed in one patient (14.3%). Overall mean DAI improved from 9.3 ± 0.6 at baseline to 4.6 ± 0.8 at 2 weeks, and then to 1.2 ± 0.5 at 12 weeks. Endoscopic examination revealed substantial amelioration of ulcers, with mucosal healing and scarring. Four patients remained in clinical remission 12 months after AM treatment. AM administration produced significant increases in plasma AM concentrations (approximately 2.5-fold) that had a mild effect on blood pressure and heart rate, but with no serious adverse effects. CONCLUSION: AM is a potentially useful agent that acts via a novel mechanism to safely induce mucosal healing and clinical remission in patients with refractory UC.

Differences in 24-h blood pressure profile of Japanese hypertensive patients under ARB treatment.

Blood pressure (BP) control throughout the entire day is recommended for cardiovascular protection. Angiotensin-II receptor blockers (ARBs) are widely used in hypertensive patients because of beneficial class effects. It is uncertain, however, whether are there any differences in 24-h BP profiles among ARBs. We examined ambulatory blood pressure monitoring (ABPM) among 211 Japanese hypertensive patients (age, 69.4 ± 9.6 years; female, 59.2%) under treatment with five different ARBs. Patients were divided into five groups according to ARBs prescribed. Patient backgrounds were almost identical in all the groups and there were no differences in office, 24-h and daytime BP; however, nighttime BP with olmesartan was significantly lower than with other ARBs. Office BPs with candesartan and telmisartan, but not other ARBs, correlated well with 24-h BP (p < 0.01). Also, there were higher correlations between daytime and nighttime BP with candesartan and telmisartan. In all patients, pulse pressure with office BP was significantly correlated with ambulatory arterial stiffness index (p = 0.001) and fluctuation of systolic BP on ABPM (p = 0.002). In conclusion, different ARB treatments produced meaningful differences in 24-h profiles.

Diuretics enhance effects of increased dose of candesartan on ambulatory blood pressure reduction in Japanese patients with uncontrolled hypertension treated with medium-dose angiotensin II receptor blockers.

Abstract Although blockade of the renin-angiotensin system by increasing the dose of angiotensin II receptor blockers (ARBs) is recommended to achieve clinical benefits in terms of blood pressure (BP) control and cardiovascular and renal outcomes, the effect of this increased dose on ambulatory BP monitoring has not been evaluated completely in Japanese patients with uncontrolled hypertension undergoing medium-dose ARB therapy. The primary objective of this study was to examine the effect of the relatively high dose of the ARB candesartan (12 mg/day) on 24-h systolic BP and the attainment of target BP levels in uncontrolled hypertension treated with a medium dose of ARBs. A total of 146 hypertensive patients (age: 69.9 ± 9.3 years; females: 65.8%) completed the study. After switching to candesartan at 12 mg/day, all these BP measurements decreased significantly (p<0.001). Attainment of the target office BP (p=0.0014) and 24-h BP levels (p=0.0296) also improved significantly. Subgroup analysis indicated that the reduction of 24-h systolic BP was larger in patients treated with diuretics than those without (p=0.0206). Multivariate analysis revealed a significant correlation between the combined ARB and diuretic therapy, and the change in 24-h systolic BP irrespective of preceding ARBs. In conclusion, the switching therapy to increased dose of candesartan caused significant reductions in office and ambulatory BP levels, and improved the attainment of target BP levels in patients with uncontrolled hypertension treated with a medium dose of ARBs. Combination with diuretics enhanced this effect.

Adrenomedullin as a potential therapeutic agent for inflammatory bowel disease.

Adrenomedullin (AM) was originally isolated from human pheochromocytoma as a biologically active peptide with potent vasodilating action but is now known to exert a wide range of physiological effects, including cardiovascular protection, neovascularization, and apoptosis suppression. A variety of tissues, including the gastrointestinal tract, have been shown to constitutively produce AM. Pro-inflammatory cytokines, such as tumor necrosis factor-α and interleukin-1, and lipopolysaccharides, induce the production and secretion of AM. Conversely, AM induces the downregulation of inflammatory cytokines in cultured cells. Furthermore, AM downregulates inflammatory processes in a variety of different colitis models, including acetic acid-induced colitis and dextran sulfate sodium-induced colitis. AM exerts antiinflammatory and antibacterial effects and stimulates mucosal regeneration for the maintenance of the colonic epithelial barrier. Here, we describe the first use of AM to treat patients with refractory ulcerative colitis. The results strongly suggest that AM has potential as a new therapeutic agent for the treatment of refractory ulcerative colitis.

Differential blood pressure reductions by angiotensin receptor blocker plus calcium channel blocker or diuretic in elderly hypertension with or without obesity.

We conducted the Miyazaki Olmesartan Therapy for Hypertension in the EldeRly (MOTHER) study, which suggested that there are preferable effects of an angiotensin receptor blocker (ARB), olmesartan, plus a calcium channel blocker (CCB) over the ARB plus a diuretic, in elderly patients with hypertension. In this subanalysis, we examined whether obesity influences the efficacies of these combination therapies. The study subjects were 58 hypertensive patients ages 65 to 85, who had been randomly assigned to either group treated with olmesartan plus a CCB or a diuretic and completed the treatment for 6 months. Systolic and diastolic blood pressures were reduced following these combination treatments in nonobese and obese patients. In the CCB combination, blood pressure reductions in nonobese patients were larger than in obese patients at 1 and 3 months, and serum creatinine remained unchanged despite the greater reduction of blood pressure. Meanwhile, such differences were not noted in the diuretic groups. Plasma aldosterone was significantly reduced in nonobese patients of two combination groups, but not in those with obesity. ARB plus CCB combination therapy might be preferably chosen for nonobese elderly patients, whereas the influence of obesity seems smaller in the efficacy of ARB plus a diuretic.

Three-year safety and effectiveness of fixed-dose losartan/hydrochlorothiazide combination therapy in Japanese patients with hypertension under clinical setting (PALM-1 Extension Study).

Concerns about metabolic complications often disturb prolonged use of diuretics in Japan. We investigated 3-year safety and efficacy in Japanese patients with hypertension who were uncontrolled with angiotensin receptor blocker or angiotensin-converting enzyme inhibitor regimens and then switched to losartan (50 mg)/hydrochlorothiazide (12.5 mg; HCTZ) combinations. Blood pressure decreased favorably and maintained a steady state for 3 years (157 ± 16/88 ± 11 mm Hg to 132 ± 13/75 ± 9 mm Hg, P < .0001). Metabolic parameters maintained a limited range of changes after 3 years, and adverse events were markedly decreased after 1-year treatment. The losartan/HCTZ combination minimized diuretic-related adverse effects and thus may be useful for the treatment of Japanese patients with hypertension.

Gut sensing of dietary K⁺ intake increases renal K⁺excretion.

Dietary K(+) intake may increase renal K(+) excretion via increasing plasma [K(+)] and/or activating a mechanism independent of plasma [K(+)]. We evaluated these mechanisms during normal dietary K(+) intake. After an overnight fast, [K(+)] and renal K(+) excretion were measured in rats fed either 0% K(+) or the normal 1% K(+) diet. In a third group, rats were fed with the 0% K(+) diet, and KCl was infused to match plasma [K(+)] profile to that of the 1% K(+) diet group. The 1% K(+) feeding significantly increased renal K(+) excretion, associated with slight increases in plasma [K(+)], whereas the 0% K(+) diet decreased K(+) excretion, associated with decreases in plasma [K(+)]. In the KCl-infused 0% K(+) diet group, renal K(+) excretion was significantly less than that of the 1% K(+) group, despite matched plasma [K(+)] profiles. We also examined whether dietary K(+) alters plasma profiles of gut peptides, such as guanylin, uroguanylin, glucagon-like peptide 1, and glucose-dependent insulinotropic polypeptide, pituitary peptides, such as AVP, α-MSH, and γ-MSH, or aldosterone. Our data do not support a role for these hormones in the stimulation of renal K(+) excretion during normal K(+) intake. In conclusion, postprandial increases in renal K(+) excretion cannot be fully accounted for by changes in plasma [K(+)] and that gut sensing of dietary K(+) is an important component of the regulation of renal K(+) excretion. Our studies on gut and pituitary peptide hormones suggest that there may be previously unknown humoral factors that stimulate renal K(+) excretion during dietary K(+) intake.

Comparison of combination therapies, including the angiotensin receptor blocker olmesartan and either a calcium channel blocker or a thiazide diuretic, in elderly patients with hypertension.

The blood pressure goals set for the treatment of hypertensive patients have been lowered in recent guidelines. To reduce blood pressure levels sufficiently, combination therapies are often needed, but there is little evidence about which combination should be chosen. The present study was carried out to compare the effects of combination therapies, including the angiotensin receptor blocker olmesartan and either a calcium channel blocker (CCB) or a thiazide diuretic, in elderly patients with hypertension. A total of 65 patients aged 65-85 years, with blood pressures of 140/90 mmHg or higher for those taking antihypertensive medication or 160/100 mmHg or higher for those not on medication, were randomly assigned to either the group treated with olmesartan plus a dihydropyridine CCB or the group treated with olmesartan plus a thiazide diuretic; 58 patients completed the treatment for 6 months. Systolic and diastolic blood pressures (SBP and DBP) were reduced during the treatment period in both the groups. The reductions in SBP at 1 and 6 months were significantly (P<0.05) greater in the CCB combination group than in the diuretic group (-29 vs. -18 mmHg, respectively, at 1 month; -32 vs. -23 mmHg, respectively, at 6 months). Despite greater reduction in SBP in the CCB group, the serum creatinine level and the estimated glomerular filtration rate (eGFR) remained unchanged, whereas in the diuretic group, creatinine was elevated (+0.06 mg per 100 ml, P<0.05) and eGFR was reduced (-4.5 mlmin(-1) per 1.73 m(2)). In addition, high-density lipoprotein cholesterol levels were reduced in the diuretic group (-5.0 mg per 100 ml, P<0.01). These results suggest that olmesartan plus a CCB is the preferable combination therapy in comparison with olmesartan plus a thiazide diuretic for elderly patients with hypertension.