Circulating microRNA Biomarkers of Thiazide Response in Hypertension

BACKGROUND

Thiazide diuretics are the second most frequently prescribed class of antihypertensives, but up to 50% of patients with hypertension have minimal antihypertensive response to thiazides. We explored circulating microRNAs (miRNAs) in search of predictive biomarkers of thiazide response.

METHODS AND RESULTS

We profiled 754 miRNAs in baseline plasma samples of 36 hypertensive European American adults treated with hydrochlorothiazide, categorized into responders (n=18) and nonresponders (n=18) on the basis of diastolic blood pressure response to hydrochlorothiazide. miRNAs with ≥2.5-fold differential expression between responders and nonresponders were considered for validation in 3 cohorts (n=50 each): hydrochlorothiazide-treated European Americans, chlorthalidone-treated European Americans, and hydrochlorothiazide-treated Black individuals. Different blood pressure phenotypes including categorical (responder versus nonresponder) and continuous diastolic blood pressure and systolic blood pressure were tested for association with the candidate miRNA expression using multivariate regression analyses adjusting for age, sex, and baseline blood pressure. After quality control, 74 miRNAs were available for screening, 19 of which were considered for validation. In the validation cohort, miR-193b-3p and 30d-5p showed significant associations with continuous SBP or diastolic blood pressure response or both, to hydrochlorothiazide in European Americans at Benjamini-Hochberg adjusted P<0.05. In the combined analysis of validation cohorts, let-7g (odds ratio, 0.6 [95% CI, 0.4-0.8]), miR-142-3p (odds ratio, 1.1 [95% CI, 1.0, 1.2]), and miR-423-5p (odds ratio, 0.7 [95% CI, 0.5-0.9]) associated with categorical diastolic blood pressure response at Benjamini-Hochberg adjusted P<0.05. Predicted target genes of the 5 miRNAs were mapped to key hypertension pathways: lysine degradation, fatty acid biosynthesis, and metabolism.

CONCLUSIONS

The above identified circulating miRNAs may have a potential for clinical use as biomarkers for thiazide diuretic selection in hypertension.

REGISTRATION

URL: ClinicalTrials.gov. Unique identifiers: NCT00246519, NCT01203852, NCT00005520.

Diuretic Strategies in Acute Decompensated Heart Failure: A Narrative Review

Background

Heart failure is a common condition with considerable associated costs, morbidity, and mortality. Patients often present to hospital with dyspnea and edema. Inadequate inpatient decongestion is an important contributor to high readmission rates. There is little evidence concerning diuresis to guide clinicians in caring for patients with acute decompensated heart failure. Contemporary diuretic strategies have been defined by expert opinion and older landmark clinical trials.

Objective

To present a narrative review of contemporary recommendations, along with their underlying evidence and pharmacologic rationale, for diuretic strategies in inpatients with acute decompensated heart failure.

Data Sources

PubMed, OVID, and Embase databases were searched from inception to December 22, 2022, with the following search terms: heart failure, acute heart failure, decompensated heart failure, furosemide, bumetanide, ethacrynic acid, hydrochlorothiazide, indapamide, metolazone, chlorthalidone, spironolactone, eplerenone, and acetazolamide.

Study Selection

Randomized controlled trials and systematic reviews involving at least 100 adult patients (> 18 years) were included. Trials involving torsemide, chlorothiazide, and tolvaptan were excluded.

Data Synthesis

Early, aggressive administration of a loop diuretic has been associated with expedited symptom resolution, shorter length of stay, and possibly reduced mortality. Guidelines make recommendations about dose and frequency but do not recommend any particular loop diuretic over another; however, furosemide is most commonly used. Guidelines recommend that the initial furosemide dose (on admission) be 2-2.5 times the patient's home dose. A satisfactory diuretic response can be defined as spot urine sodium content greater than 50-70 mmol/L at 2 hours; urine output greater than 100-150 mL/h in the first 6 hours or 3-5 L in 24 hours; or a change in weight of 0.5-1.5 kg in 24 hours. If congestion persists after the maximization of loop diuretic therapy over the first 24-48 hours, an adjunctive diuretic such as thiazide or acetazolamide should be added. If decongestion targets are not met, continuous infusion of furosemide may be considered.

Conclusions

Heart failure with congestion can be managed with careful administration of high-dose loop diuretics, supported by thiazides and acetazolamide when necessary. Clinical trials are underway to further evaluate this strategy.

Potassium Magnesium Citrate Is Superior to Potassium Chloride in Reversing Metabolic Side Effects of Chlorthalidone

BACKGROUND

Thiazide diuretics (TD) are the first-line treatment of hypertension because of its consistent benefit in lowering blood pressure and cardiovascular risk. TD is also known to cause an excess risk of diabetes, which may limit long-term use. Although potassium (K) depletion was thought to be the main mechanism of TD-induced hyperglycemia, TD also triggers magnesium (Mg) depletion. However, the role of Mg supplementation in modulating metabolic side effects of TD has not been investigated. Therefore, we aim to determine the effect of potassium magnesium citrate (KMgCit) on fasting plasma glucose and liver fat by magnetic resonance imaging during TD therapy.

METHODS

Accordingly, we conducted a double-blinded RCT in 60 nondiabetic hypertension patients to compare the effects of KCl versus KMgCit during chlorthalidone treatment. Each patient received chlorthalidone alone for 3 weeks before randomization. Primary end point was the change in fasting plasma glucose after 16 weeks of KCl or KMgCit supplementation from chlorthalidone alone.

RESULTS

The mean age of subjects was 59±11 years (30% Black participants). Chlorthalidone alone induced a significant rise in fasting plasma glucose, and a significant fall in serum K, serum Mg, and 24-hour urinary citrate excretion (all P<0.05). KMgCit attenuated the rise in fasting plasma glucose by 7.9 mg/dL versus KCl (P<0.05), which was not observed with KCl. There were no significant differences in liver fat between the 2 groups.

CONCLUSIONS

KMgCit is superior to KCl, the common form of K supplement used in clinical practice, in preventing TD-induced hyperglycemia. This action may improve tolerability and cardiovascular safety in patients with hypertension treated with this drug class.

Hypertension in chronic kidney disease-treatment standard 2023

Hypertension is very common and remains often poorly controlled in patients with chronic kidney disease (CKD). Accurate blood pressure (BP) measurement is the essential first step in the diagnosis and management of hypertension. Dietary sodium restriction is often overlooked, but can improve BP control, especially among patients treated with an agent to block the renin-angiotensin system. In the presence of very high albuminuria, international guidelines consistently and strongly recommend the use of an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker as the antihypertensive agent of first choice. Long-acting dihydropyridine calcium channel blockers and diuretics are reasonable second- and third-line therapeutic options. For patients with treatment-resistant hypertension, guidelines recommend the addition of spironolactone to the baseline antihypertensive regimen. However, the associated risk of hyperkalemia restricts the broad utilization of spironolactone in patients with moderate-to-advanced CKD. Evidence from the CLICK (Chlorthalidone in Chronic Kidney Disease) trial indicates that the thiazide-like diuretic chlorthalidone is effective and serves as an alternative therapeutic opportunity for patients with stage 4 CKD and uncontrolled hypertension, including those with treatment-resistant hypertension. Chlorthalidone can also mitigate the risk of hyperkalemia to enable the concomitant use of spironolactone, but this combination requires careful monitoring of BP and kidney function for the prevention of adverse events. Emerging agents, such as the non-steroidal mineralocorticoid receptor antagonist ocedurenone, dual endothelin receptor antagonist aprocitentan and the aldosterone synthase inhibitor baxdrostat offer novel targets and strategies to control BP better. Larger and longer term clinical trials are needed to demonstrate the safety and efficacy of these novel therapies in the future. In this article, we review the current standards of treatment and discuss novel developments in pathophysiology, diagnosis, outcome prediction and management of hypertension in patients with CKD.

Chlorthalidone-Induced Fixed-Drug Eruption: Unmasking an Uncommon Reaction to a Common Diuretic

Fixed-drug eruptions (FDEs) are dermatological reactions characterized by specific skin lesions triggered by certain medications. Our case reports commonly used medications that can cause drug-induced skin reactions. Chlorthalidone, a widely used diuretic, had not been prominently linked to FDEs. Here, we present the case of a 45-year-old African-American male who developed classic FDE skin lesions following the initiation of chlorthalidone therapy. This case underscores the imperative for further investigation and heightened awareness among healthcare professionals regarding chlorthalidone-associated FDEs. Findings suggest that such reactions might be more prevalent than previously acknowledged, underscoring the significance of prompt diagnosis and effective management of drug-induced skin responses. Notably, the patient's lesions showed complete resolution upon discontinuing the diuretic, reinforcing the causal relationship. This case is an essential reminder of the importance of vigilance in monitoring patients for adverse drug reactions, even in unlikely medications, such as chlorthalidone.​​​​​​.

Efficacy and safety of standard dose triple combination of telmisartan 80 mg/amlodipine 5 mg/chlorthalidone 25 mg in primary hypertension: A randomized, double-blind, active-controlled, multicenter phase 3 trial

The authors evaluated the efficacy, safety, and characteristics of patients who respond well to standard dose triple combination therapy including chlorthalidone 25 mg with telmisartan 80 mg plus amlodipine 5 mg in hypertensive patients. This is a multicenter, double-blind, active-controlled, phase 3, randomized trial. Patients are randomized to triple combination (telmisartan 40 mg/amlodipine 5 mg/chlorthalidone 12.5 mg, TEL/AML/CHTD group) or dual combination (telmisartan 40 mg/amlodipine 5 mg, TEL/AML group) treatment and then dose up titration to TEL 80/AML5/CHTD25mg and TEL80/AML5, respectively. The primary endpoint is the change of mean sitting systolic blood pressure (MSSBP) at week 8. A Target BP achievement rate, a response rate, and the safety endpoints are also evaluated. Total 374 patients (mean age = 60.9 ± 10.7 years, male = 78.3%) were randomized to the study. The baseline MSSBPs/diastolic BPs were 149.9 ± 12.2/88.5 ± 10.4 mm Hg. After 8 weeks treatment, the change of MSSBPs at week 8 are -19.1 ± 14.9 mm Hg (TEL/AML/CHTD) and -11.4 ± 14.7 mm Hg (TEL/AML) (p < .0001). The achievement rates of target BP (53.8% vs. 37.8%, p = .0017) and responder rate (54.8% vs. 35.6%, p = .0001) at week 8 were significantly higher in TEL/AML/CHTD. There are no serious adverse event and no one discontinued medication due to adverse event. Among the TEL 80/AML5/CHTD25mg treatment group, patients of female or age ≥ 65 years old showed higher rate of target BP achievement than relatively young male. (61.4 vs. 46.8%, p = .042) Our study showed standard dose triple combination of telmisartan 80 mg/amlodipine 5 mg/chlorthalidone 25 mg is efficacious and safe in treatment of primary hypertension. Target BP achievement with triple therapy would be facilitated in female or old age.

Exploring the Effectiveness and Safety of Azilsartan-Medoxomil/Chlorthalidone Versus Olmesartan-Medoxomil/Hydrochlorothiazide in Hypertensive Patients: A Meta-Analysis

This study aims to assess the effectiveness and safety of azilsartan-medoxomil/chlorthalidone (AZI-M/CT) compared to olmesartan-medoxomil/hydrochlorothiazide (OLM/HCTZ) in patients with hypertension. Systematic searches were conducted on PubMed, Google Scholar, and ClinicalTrials.gov, starting from their establishment until March 15, 2023. The purpose of these searches was to locate original reports that compare the effectiveness of AZI-M/CT and OLM/HCTZ in treating hypertension. Data on various characteristics at the beginning and end of the studies were gathered. The analyses were carried out using Review Manager 5.4.1 (The Nordic Cochrane Center, The Cochrane Collaboration, 2014, Odense, Denmark) and STATA 16.0 software (Stata Corp. LP, College Station, TX, USA). Risk ratios (RRs) and weighted mean differences (WMDs) with 95% confidence intervals (CIs) were calculated as part of the study. A total of 3,146 individuals from four separate investigations were included in the study, with 1,931 individuals receiving AZI-M/CT and 1,215 individuals receiving OLM/HCTZ. The combined analysis revealed that the average diastolic blood pressure (DBP) was significantly lower in the AZI-M/CT group compared to the OLM/HCTZ group (WMD -2.64 [-2.78, -2.51]; P = 0.00001; I² = 1%). However, there were no significant differences in mean systolic blood pressure (SBP; WMD -2.95 [-6.64, 0.73]; P = 0). Furthermore, the AZI-M/CT group had a notably higher incidence of major adverse events (RR 1.58 [1.20, 2.08]; P = 0.001; I² = 11%) and any treatment-emergent adverse events (RR 1.11 [1.03, 1.20]; P = 0.007; I² = 51%). However, there was no significant difference in the mortality risk between the two groups (RR 0.74 [0.14, 3.91]; P = 0.72; I² = 0%). Based on the results of our meta-analysis, AZI-M/CT is more effective than OLM/HCTZ at reducing blood pressure in elderly hypertensive patients. However, because of the small sample size, favorable results must be carefully reevaluated, and more studies are needed.

Comparison of the Effectiveness and Safety of Chlorthalidone and Hydrochlorothiazide in Patients With Hypertension: A Meta-Analysis

The aim of this study was to compare the effectiveness and safety of chlorthalidone and hydrochlorothiazide in patients with hypertension. The present meta-analysis was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Our search for relevant articles was conducted on PubMed, Scopus, and CINAHIL databases from their inception until March 31, 2023. Keywords used to search for relevant articles included "hydrochlorothiazide," "chlortalidone," "hypertension," "cardiovascular," and "blood pressure." The outcomes assessed in this meta-analysis included changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP). Myocardial infarction, stroke, and all-cause mortality were also assessed. For safety analysis, we evaluated the risk of hypokalemia between the two groups. Any disagreement between the two authors in the data extraction process was resolved through discussion. Eight studies fulfilled the inclusion criteria included in the present meta-analysis. Our analysis showed that chlorthalidone was superior to hydrochlorothiazide in controlling both SBP and DBP, with no significant heterogeneity reported. However, there was no significant difference between the two groups in terms of the risk of myocardial infarction, stroke, all-cause mortality, and hospitalization due to heart failure. The hypokalemia rate was reported to be higher with chlorthalidone compared to hydrochlorothiazide.

Efficacy and safety of low-dose antihypertensive combination of amlodipine, telmisartan, and chlorthalidone: A randomized, double-blind, parallel, phase II trial

The aim of this clinical trial was to assess the efficacy and safety of low‐dose triple combinations of amlodipine, telmisartan, and chlorthalidone in patients with essential hypertension. After a 2‐week placebo run‐in period, 176 patients were randomized to seven treatment groups (placebo, quarter‐dose combination, third‐dose combination, half‐dose combination, amlodipine 5 mg, amlodipine 10 mg, and telmisartan 80 mg) and administered the assigned study drug orally for 8 weeks. The primary efficacy endpoint was the change in the mean sitting systolic blood pressure (BP) (MSSBP) at Week 8. The MSSBP and mean sitting diastolic BP in the quarter‐dose and half‐dose groups were significantly lower compared to the placebo and amlodipine 5 mg groups, with similar BP‐lowering effects observed compared to the amlodipine 10 mg and telmisartan 80 mg groups. However, the third‐dose group showed significant BP improvement only compared to the placebo group. A similar pattern was observed for the control rate of hypertension and response rates. Additional analysis was conducted after correcting for gender and age effects, and, as a result, the third‐dose group showed similar results with regard to the BP‐lowering effect as the quarter‐dose and half‐dose groups. In terms of safety, no special adverse events and clinically significant results were noted, and all dose groups of the triple combination are considered safe for use in essential hypertension patients. The current findings indicated that low‐dose triple combination of amlodipine, telmisartan, and chlorthalidone over 8 weeks effectively improved the BP‐lowering effect in patients with essential hypertension without any safety concerns.

Thiazide diuretics are back in CKD: the case of chlorthalidone

Sodium and volume excess is the fundamental risk factor underlying hypertension in chronic kidney disease (CKD) patients, who represent the prototypical population characterized by salt-sensitive hypertension. Low salt diets and diuretics constitute the centrepiece for blood pressure control in CKD. In patients with CKD stage 4, loop diuretics are generally preferred to thiazides. Furthermore, thiazide diuretics have long been held as being of limited efficacy in this population. In this review, by systematically appraising published randomized trials of thiazides in CKD, we show that this class of drugs may be useful even among people with advanced CKD. Thiazides cause a negative sodium balance and reduce body fluids by 1-2 l within the first 2-4 weeks and these effects go along with improvement in hypertension control. The recent CLICK trial has documented the antihypertensive efficacy of chlorthalidone, a long-acting thiazide-like diuretic, in stage 4 CKD patients with poorly controlled hypertension. Overall, chlorthalidone use could be considered in patients with treatment-resistant hypertension when spironolactone cannot be administered or must be withdrawn due to side effects. Hyponatremia, hypokalaemia, volume depletion and acute kidney injury are side effects that demand a vigilant attitude by physicians prescribing these drugs. Well-powered randomized trials assessing hard outcomes are still necessary to more confidently recommend the use of these drugs in advanced CKD.

Thiazide and the Thiazide-Like Diuretics: Review of Hydrochlorothiazide, Chlorthalidone, and Indapamide

The term thiazide is universally understood to refer to diuretics that exert their principal action in the distal tubule. The thiazide class is heterogenous and can be further subdivided into compounds containing the benzothiadiazine ring structure-the thiazide-type (e.g., hydrochlorothiazide)-and those lacking the benzothiadiazine ring-the thiazide-like (e.g., chlorthalidone and indapamide) drugs. Thiazide-like agents are longer acting and constitute the diuretics used in most of the cardiovascular outcome trials that established benefits of treatment with diuretics, but pragmatic aspects, such as lack of availability in convenient formulations, limit their use. Regardless of class heterogeneity, thiazides have retained importance in the management of hypertension for over 60 years. They are reliably effective as monotherapy in a majority of hypertensive patients, and augment the efficacy of other classes of antihypertensives when used in combination. Importantly, a thiazide-based treatment regimen lowers cardiovascular events, and their sturdy effect reinforces their place among the recommended first-line agents to treat hypertension in major domestic and international hypertension guidelines. There are few head-to-head comparisons within the class, but potential differences have been explored indirectly as well as in non-blood pressure mechanisms and potential pleiotropic properties. Until proven otherwise, the importance of these differences remains speculative, and clinicians should assume that cardiovascular events will be lowered similarly across agents when equivalent blood pressure reduction occurs. Thiazides remain underutilized, with only about one-third of hypertensive patients receiving them. For many patients, however, a thiazide is an indispensable component of their regimen to achieve adequate blood pressure control.

Clinical effectiveness and safety of amlodipine/losartan-based single-pill combination therapy in patients with hypertension: Findings from real-world, multicenter observational databases

Various single‐pill combinations (SPCs) have been introduced to improve drug compliance and clinical efficacy. However, there is a lack of real‐world evidence regarding the effectiveness of these SPCs for hypertension. This study evaluated the real‐world clinical efficacy and safety of amlodipine/losartan‐based SPC therapies in patients with hypertension in a real‐world setting. A total of 15 538 patients treated with amlodipine/losartan‐based SPCs [amlodipine + losartan (AL), amlodipine + losartan + rosuvastatin (ALR), and amlodipine + losartan + chlorthalidone (ALC)] were selected from the database of three tertiary hospitals in Korea. The efficacy endpoints were target blood pressure (BP) and low‐density lipoprotein cholesterol (LDL‐C) achievement rates. Safety was evaluated based on laboratory parameters. Drug adherence was defined as the proportion of medication days covered (PDC). The target BP attainment rate was above 90% and was similar among the three groups. Although many patients in the AL and ALC groups took statins, the target LDL‐C attainment rate was significantly higher in the ALR group than in the AL and ALC groups. Safety endpoints were not significantly different among the groups, except serum uric acid level and incidence rate of new‐onset hyperuricemia, which were significantly lower in the AL and ALR groups than in the ALC group. The PDC was > 90% in all groups. In the real‐world hypertensive patients, amlodipine/losartan‐based SPC therapy demonstrated good target BP achievement rates. Especially, rosuvastatin‐combination SPC showed better target LDL‐C goal achievement rate compared to the other SPCs. All three amlodipine/losartan‐based SPC had excellent drug adherence.

Effects of Spironolactone and Chlorthalidone on Cardiovascular Structure and Function in Chronic Kidney Disease: A Randomized, Open-Label Trial

BACKGROUND AND OBJECTIVES

In a randomized double-blind, placebo-controlled trial, treatment with spironolactone in early-stage CKD reduced left ventricular mass and arterial stiffness compared with placebo. It is not known if these effects were due to BP reduction or specific vascular and myocardial effects of spironolactone.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A prospective, randomized, open-label, blinded end point study conducted in four UK centers (Birmingham, Cambridge, Edinburgh, and London) comparing spironolactone 25 mg to chlorthalidone 25 mg once daily for 40 weeks in 154 participants with nondiabetic stage 2 and 3 CKD (eGFR 30-89 ml/min per 1.73 m²). The primary end point was change in left ventricular mass on cardiac magnetic resonance imaging. Participants were on treatment with an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker and had controlled BP (target ≤130/80 mm Hg).

RESULTS

There was no significant difference in left ventricular mass regression; at week 40, the adjusted mean difference for spironolactone compared with chlorthalidone was -3.8 g (95% confidence interval, -8.1 to 0.5 g, P=0.08). Office and 24-hour ambulatory BPs fell in response to both drugs with no significant differences between treatment. Pulse wave velocity was not significantly different between groups; at week 40, the adjusted mean difference for spironolactone compared with chlorthalidone was 0.04 m/s (-0.4 m/s, 0.5 m/s, P=0.90). Hyperkalemia (defined ≥5.4 mEq/L) occurred more frequently with spironolactone (12 versus two participants, adjusted relative risk was 5.5, 95% confidence interval, 1.4 to 22.1, P=0.02), but there were no patients with severe hyperkalemia (defined ≥6.5 mEq/L). A decline in eGFR >30% occurred in eight participants treated with chlorthalidone compared with two participants with spironolactone (adjusted relative risk was 0.2, 95% confidence interval, 0.05 to 1.1, P=0.07).

CONCLUSIONS

Spironolactone was not superior to chlorthalidone in reducing left ventricular mass, BP, or arterial stiffness in nondiabetic CKD.

Monotherapy treatment with chlorthalidone or amlodipine in the systolic blood pressure intervention trial (SPRINT)

This post hoc analysis of the Systolic Blood Pressure Intervention Trial (SPRINT) examined the performance of chlorthalidone (C) versus amlodipine (A) monotherapies. ANOVA was used to analyze the differences in systolic blood pressure (SBP) response between C and A. Logistic regression was used to examine monotherapy failure (adding a second antihypertensive agent or switching to a different antihypertensive agent) rates. Four hundred ninety-one participants were treated with C monotherapy (n = 210, mean dose = 22 mg/day) or A monotherapy (n = 281, mean dose = 7 mg/day). There was a significant difference in mean SBP reduction between the C and A monotherapies at the third visit (higher reduction with A, adjusted p = .018). Unadjusted analysis showed a higher failure with C in the standard treatment group. Although the average SBP at failure was higher and above the 140 mm Hg cutoff that indicated monotherapy failure with A (142.60) compared with C (138.40), more participants on C failed despite having SBP below the 140 cutoff. This was probably due to decisions made by the investigative teams to change the antihypertensive regimen, because, in their opinion, the clinical picture required it. After adjusting for baseline characteristics, C had higher failure than A only in the standard treatment group (1.64 odds ratio [OR], 95% CI 1.06-2.56, p = .028). A sub-analysis including participants who had never used antihypertensive treatment before randomization had similar results (2.57 OR, 95% CI 1.34-5.02, p = .004). Overall, in SPRINT chlorthalidone was associated with higher monotherapy failure than amlodipine in the standard treatment group because of decisions of the investigative teams.

Pharmacokinetics of a Fixed-Dose Combination of Amlodipine/Losartan and Chlorthalidone Compared to Concurrent Administration of the Separate Components

Hypertension is more effectively treated with coadministration of 2 or more antihypertensive drugs than with high-dose monotherapy. Therefore, calcium channel blockers, angiotensin II receptor blockers, and thiazides are coadministered to treat hypertension. The objective of this study was to compare the pharmacokinetic (PK) profiles of HCP1401, a fixed-dose combination of amlodipine 5 mg, losartan 100 mg, and chlorthalidone 25 mg, with the separate components (loose combination) of amlodipine/losartan 5/100 mg and chlorthalidone 25 mg. A randomized, open-label, single-dose, 2-way crossover study was conducted. Blood samples for amlodipine and chlorthalidone were collected for up to 144 hours after dosing, whereas those for losartan were collected up to 48 hours after dosing. The PK parameters of these drugs were calculated using a noncompartmental method. Sixty subjects completed the study. The geometric mean ratios and 90% confidence intervals of maximum plasma concentration and area under the concentration-time curve to the last measurable point for amlodipine, losartan, and chlorthalidone were within the conventional bioequivalence range of 0.80 to 1.25. There were no clinically significant changes in safety assessments, and the treatments were well tolerated. The PK characteristics and tolerability profiles of a single oral FDC of amlodipine, losartan, and chlorthalidone were equivalent to those of individual tablets in a loose combination.

Synchronized determination of sacubitril and valsartan with some co-administered drugs in human plasma via UPLC-MS/MS method using solid-phase extraction

An accurate and sensitive UPLC-MS/MS method was developed and validated for the simultaneous estimation of the newly developed combination of sacubitril and valsartan and the co-administered drugs nebivolol, chlorthalidone and esomeprazole in human plasma. Solid-phase extraction was conducted for the purification and extraction of the drugs from human plasma. Chromatographic separation was carried out on an Agilent SB-C₁₈ (1.8 μm, 2.1 × 50 mm) column using losartan as internal standard. Isocratic elution was applied using acetonitrile-0.1% formic acid in water (85: 15, v/v) as mobile phase. Detection was carried out using a triple-quadrupole tandem mass spectrometer using multiple reaction monitoring, at positive mode at m/z 412.23 → 266.19 for sacubitril, m/z 436.29 → 235.19 for valsartan, m/z 405.8 → 150.98 for nebivolol, m/z 346.09 → 198 for esomeprazole and a selected combination of two fragments m/z 423.19 → 207.14 and 423.19 → 192.2 for losartan (internal standard), and in negative ionization mode at m/z 337.02 → 190.12 for chlorthalidone. The method was linear over the concentration ranges 30-2,000 ng/ml for sacubitril, 70-2,000 ng/ml for valsartan, esomeprazole and chlorthalidone and 70-5,000 pg/ml for nebivolol. The developed method is sensitive and selective and could be applied for dose adjustment, bioavailability and drug-drug interaction studies.

Chlorthalidone with potassium citrate decreases calcium oxalate stones and increases bone quality in genetic hypercalciuric stone-forming rats

To study human idiopathic hypercalciuria we developed an animal model, genetic hypercalciuric stone-forming rats, whose pathophysiology parallels that of human idiopathic hypercalciuria. Fed the oxalate precursor, hydroxyproline, every rat in this model develops calcium oxalate stones. Using this rat model, we tested whether chlorthalidone and potassium citrate combined would reduce calcium oxalate stone formation and improve bone quality more than either agent alone. These rats (113 generation) were fed a normal calcium and phosphorus diet with hydroxyproline and divided into four groups: diets plus potassium chloride as control, potassium citrate, chlorthalidone plus potassium chloride, or potassium citrate plus chlorthalidone. Urine was collected at six, 12, and 18 weeks and kidney stone formation and bone parameters were determined. Compared to potassium chloride, potassium citrate reduced urinary calcium, chlorthalidone reduced it further and potassium citrate plus chlorthalidone even further. Potassium citrate plus chlorthalidone decreased urine oxalate compared to all other groups. There were no significant differences in calcium oxalate supersaturation in any group. Neither potassium citrate nor chlorthalidone altered stone formation. However, potassium citrate plus chlorthalidone significantly reduced stone formation. Vertebral trabecular bone increased with chlorthalidone and potassium citrate plus chlorthalidone. Cortical bone area increased with chlorthalidone but not potassium citrate or potassium citrate plus chlorthalidone. Mechanical properties of trabecular bone improved with chlorthalidone, but not with potassium citrate plus chlorthalidone. Thus in genetic hypercalciuric stone-forming rats fed a diet resulting in calcium oxalate stone formation, potassium citrate plus chlorthalidone prevented stone formation better than either agent alone. Chlorthalidone alone improved bone quality, but adding potassium citrate provided no additional benefit.

Network meta-analysis of efficacy and safety of chlorthalidone and hydrochlorothiazide in hypertensive patients

Hypertension is a chronic condition leading to increased stress on the heart and blood vessels, a critical risk factor for clinically significant events such as myocardial infarction heart failure, stroke and death. Chlorthalidone and hydrochlorothiazide are first-line antihypertensive agents for most patients with hypertension. The aim of our meta-analysis was to compare the efficacy and safety of both therapies in patients with hypertension. Searches of electronic databases PubMed, MEDLINE, Scopus, PsycInfo and eLIBRARY.ru, were performed. We used network meta-analysis to combine direct and indirect evidence. Forest plots and closed loops depict estimated results from studies included in our meta-analysis. Of 1289 identified sources, only 37 were included in our meta-analysis. Our analysis has demonstrated a slight superiority for chlorthalidone regarding SBP and not statistically significant differences regarding DBP. Simultaneously, hydrochlorothiazide seems to be a safer choice of therapy, as evidenced by the levels of serum potassium. The two diuretics can be used interchangeably.

Low-Dose Triple Antihypertensive Combination Therapy in Patients with Hypertension: A Randomized, Double-Blind, Phase II Study

Purpose

We evaluated the dose-responsiveness, efficacy, and safety of low-dose triple antihypertensive combination therapies in patients with mild-to-moderate hypertension.

Patients and Methods

After a 1 to 2-week placebo run-in period, 248 patients were randomized to the half-dose triple combination (amlodipine 2.5 mg + losartan 25 mg + chlorthalidone 6.25 mg), third-dose triple combination (amlodipine 1.67 mg + losartan 16.67 mg + chlorthalidone 4.17 mg), quarter-dose triple combination (amlodipine 1.25 mg + losartan 12.5 mg + chlorthalidone 3.13mg), amlodipine 10mg, amlodipine 5mg, losartan 100mg, and placebo groups for 8 weeks. The primary outcome was the mean change in systolic blood pressure (SBP) from baseline to week 8.

Results

The placebo-corrected SBP reductions of the half-dose, third-dose, quarter-dose combination, amlodipine 10 mg, amlodipine 5 mg and losartan 100 mg treatments were −17.2, −19.5, −14.9, −18.5, −11.3 and −9.9 mmHg, respectively. The BP control and response rates were significantly higher in the half-dose, third-dose, and quarter-dose combination groups than in the placebo group (all p < 0.01). Despite no intergroup differences in study drug-related adverse events, ankle circumference increased significantly in the amlodipine group compared to those in the combination treatment groups. The quarter-dose combination, amlodipine 5 mg, and losartan 100 mg groups showed similar SBP reduction and BP response rates. The SBP reduction and BP response rate in the third-dose and half-dose combination groups were not significantly different from those in the amlodipine 10 mg group but superior to those in the losartan 100 mg group.

Conclusion

Low-dose triple combination therapies could be effective as antihypertensive therapies.

Trial Registration

ClinicalTrials.gov identifier NCT03897868.

Acute interstitial nephritis and drug-induced systemic lupus erythematosus due to chlorthalidone and amiodarone: A case report

Drug-induced lupus erythematosus has features distinct from primary systemic lupus erythematosus. It can occur with a wide variety of agents that result in the generation of anti-histone or other types of antibodies. Systemic manifestations of drug-induced systemic lupus erythematosus may include renal dysfunction due to circulating immune complexes or due to other immune reactions to the culprit medication(s). Acute interstitial nephritis occurs due to DNA–drug or protein–drug complexes that trigger an allergic immune response. We report a patient who developed acute kidney injury, rash, and drug-induced systemic lupus diagnosed by serologies after starting chlorthalidone and amiodarone. A renal biopsy showed acute interstitial nephritis and not lupus-induced glomerulonephritis. It is important to note that systemic lupus erythematosus and acute interstitial nephritis can occur together, and this report highlights the role of the kidney biopsy in ascertaining the pathological diagnosis and outlining therapy in drug-induced lupus erythematosus.

Treatment of Resistant and Refractory Hypertension

Resistant hypertension (RHTN) is defined as uncontrolled blood pressure despite the use of ≥3 antihypertensive agents of different classes, including a diuretic, usually thiazide-like, a long-acting calcium channel blocker, and a blocker of the renin- angiotensin system, either an ACE (angiotensin-converting enzyme) inhibitor or an ARB (angiotensin receptor blocker), at maximal or maximally tolerated doses. Antihypertensive medication nonadherence and the white coat effect, defined as elevated blood pressure when measured in clinic but controlled when measured outside of clinic, must be excluded to make the diagnosis. RHTN is a high-risk phenotype, leading to increased all-cause mortality and cardiovascular disease outcomes. Healthy lifestyle habits are associated with reduced cardiovascular risk in patients with RHTN. Aldosterone excess is common in patients with RHTN, and addition of spironolactone or amiloride to the standard 3-drug antihypertensive regimen is effective at getting the blood pressure to goal in most of these patients. Refractory hypertension is defined as uncontrolled blood pressure despite use of ≥5 antihypertensive agents of different classes, including a long-acting thiazide-like diuretic and an MR (mineralocorticoid receptor) antagonist, at maximal or maximally tolerated doses. Fluid retention, mediated largely by aldosterone excess, is the predominant mechanism underlying RHTN, while patients with refractory hypertension typically exhibit increased sympathetic nervous system activity.

Effects of Antihypertensive Class on Falls, Syncope, and Orthostatic Hypotension in Older Adults: The ALLHAT Trial

Hypertension treatment has been implicated in falls, syncope, and orthostatic hypotension (OH), common events among older adults. Whether the choice of antihypertensive agent influences the risk of falls, syncope, and OH in older adults is unknown. ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) was a randomized clinical trial that compared the effects of hypertension first-step therapy on fatal coronary heart disease or nonfatal myocardial infarction (1994-2002). In a subpopulation of ALLHAT participants, age 65 years and older, we determined the relative risk of falls, syncope, OH, or a composite based on Centers for Medicare and Medicaid Services and Veterans Affairs claims, using Cox regression. We also determined the adjusted association of self-reported atenolol use (ascertained at the 1-month visit for indications other than hypertension) on outcomes in Cox models adjusted for age, sex, and race. Among 23 964 participants (mean age 69.8±6.8 years, 45% women, 31% non-Hispanic black) followed for a mean of 4.9 years, we identified 267 falls, 755 syncopes, 249 OH, and 1157 composite claims. There were no significant differences in the cumulative incidences of events across randomized drug assignments. However, amlodipine increased risk of falls during the first year of follow-up compared with chlorthalidone (hazard ratio [95% CI]: 2.24 [1.06-4.74]; P=0.03) or lisinopril (hazard ratio [95% CI]: 2.61 [1.03-6.72]; P=0.04). Atenolol use (N=928) was not associated with any of the 3 individual or composite claims. In older adults, the choice of antihypertensive agent had no effect on risk of fall, syncope, or OH long-term. However, amlodipine increased risk of falls within 1 year of initiation. These short-term findings require confirmation. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000542.

Hydrochlorothiazide vs chlorthalidone, indapamide, and potassium-sparing/hydrochlorothiazide diuretics for reducing left ventricular hypertrophy: A systematic review and meta-analysis

Left ventricular hypertrophy develops in 36%-41% of hypertensive patients and independently predicts cardiovascular events and total mortality. Moreover, drug-induced reduction in left ventricular mass (LVM) correlates with improved prognosis. The optimal thiazide-type diuretic for reducing LVM is unknown. Evidence regarding potency, cardiovascular events, sodium, and potassium suggested the hypothesis that "CHIP" diuretics (CHlorthalidone, Indapamide, and Potassium-sparing diuretic/hydrochlorothiazide [PSD/HCTZ]) would reduce LVM more than HCTZ. Systematic searches of five databases were conducted. Among the 38 randomized trials, a 1% reduction in systolic blood pressure (SBP) predicted a 1% reduction in LVM, P = 0.00001. CHIP-HCTZ differences in reducing LVM differed across trials (ie, heterogeneity), making interpretation uncertain. However, among the 28 double-blind trials, heterogeneity was undetectable, and HCTZ reduced LVM (percent reduction [95% CI]) by -7.3 (-10.4, -4.2), P < 0.0001. CHIP diuretics surpassed HCTZ in reducing LVM: chlorthalidone -8.2 (-14.7, -1.6), P = 0.015; indapamide -7.5 (-12.7, -2.3), P = 0.005; and all CHIP diuretics combined -7.7 (-12.2, -3.1), P < 0.001. The comparison of PSD/HCTZ with HCTZ had low statistical power but favored PSD/HCTZ: -6.0 (-14.1, +2.1), P = 0.149. Thus, compared to HCTZ, CHIP diuretics had twice the effect on LVM. CHIP diuretics did not surpass HCTZ in reducing systolic or diastolic blood pressure: -0.3 (-5.0, +4.3) and -1.6 (-5.6, +2.4), respectively. The strength of evidence that CHIP diuretics surpass HCTZ for reducing LVM was high (GRADE criteria). In conclusion, these novel results have demonstrated that CHIP diuretics reduce LVM 2-fold more than HCTZ among hypertensive patients. Although generally related to LVM, blood pressure fails to explain the superiority of CHIP diuretics for reducing LVM.

Combined Valsartan and Chlorthalidone in Patients With Mild to Moderate Hypertension: The VACLOR Study

Objective:

To evaluate the efficacy and safety of valsartan (V) or chlorthalidone (C) monotherapy in comparison with a fixed combination of valsartan and chlorthalidone (V + C).

Methods:

This 12-week multicenter randomized three-arm open-label study randomly allocated 72 patients to V or C as monotherapy or a combination of V + C. The aim was to measure changes in office systolic blood pressure (SBP) and diastolic blood pressure (DBP) and in 24-hour ambulatory blood pressure monitoring (ABPM) from baseline to week 12, in addition to medication tolerability.

Results:

The proportion of patients achieving target BP in office at week 12 was not statistically different for the three groups. However, comparisons of daytime and nighttime 24-hour ABPM values from baseline to week 12 revealed significant differences in nighttime mean SBP for the three groups, due to a significantly greater reduction in the values in patients assigned to the V + C group (−14.7 vs. −8.7 vs. −10.7, P = .042, V+C; V; C, respectively). Although patients assigned to the V + C group also had greater nighttime reduction in mean DBP values compared with those in the other groups, this difference was not statistically significant. The incidence of adverse events did not differ significantly.

Conclusion:

In patients with hypertension treated with V, C, and both medications combined, the fixed combination of V + C provided a significantly greater reduction of late night to early morning BP values when interventions were assessed with 24-hour ABPM.

Trial registration:

clinicaltrials.gov Identifier: NCT.01850160, https://clinicaltrials.gov/ct2/show/NCT01850160

A randomized trial of the efficacy and safety of azilsartan medoxomil combined with chlorthalidone

INTRODUCTION

We measured the effects of azilsartan medoxomil co-administered with chlorthalidone 25 mg in stage 2 hypertension.

METHODS

Azilsartan medoxomil 40 or 80 mg plus chlorthalidone were compared with placebo plus chlorthalidone once daily in a randomized, double-blind, 6-week trial. The primary endpoint was change from baseline in 24-hour mean systolic blood pressure by ambulatory blood pressure monitoring.

RESULTS

Patients ( N=551; mean age 59 years; 51.7% men) were randomly assigned to placebo plus chlorthalidone ( n=184), azilsartan medoxomil 40 mg plus chlorthalidone ( n=185), or azilsartan medoxomil 80 mg plus chlorthalidone ( n=182). Baseline systolic blood pressures were similar among groups. After 6 weeks, least squares mean (standard error) reductions with azilsartan medoxomil 40 mg and 80 mg plus chlorthalidone were similar in magnitude (-31.7 (1.0) and -31.3 (1.0) mmHg, respectively), but greater than chlorthalidone alone (-15.9 (1.0) mmHg). Hypotension and serum creatinine elevations were more frequent with azilsartan medoxomil plus chlorthalidone than chlorthalidone alone (reversed with drug discontinuation). Notably, plasma potassium reduction of 0.43 meq/L with chlorthalidone was attenuated to 0.13 and 0.05 meq/L by azilsartan medoxomil 40 mg and 80 mg, respectively.

CONCLUSION

Azilsartan medoxomil 40 mg or 80 mg plus chlorthalidone 25 mg was significantly more efficacious than chlorthalidone alone in reducing blood pressure and was well tolerated. Clinicaltrial.gov , https://clinicaltrials.gov/ct2/show/NCT00591773 , NCT00591773.

Azilsartan and Chlorthalidone-new Powerful Fixed dose Antihypertensive Combination

Arterial hypertension is a disease that still affects a major part of the population worldwide, and leads to fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. From the CDC statistical analysis, as regarding to United States, 1 of every 3 adults has high blood pressure, and οnly about half (54%) of them have it under control. Furthermore, all that leads to a nation cost about $46 billion each year. Efforts to find new ways to regulate arterial hypertension are therefore imperative. In our days, a lot of references have been made to the use of a new therapeutic combination, that of azilsartan - an innovative ARB, in combination with chlorthalidone. Ιn fact, it is a combination now prescribed in a number of countries. A significant number of trials shows both azilsartan vs popular antihypertensive drugs, as well as chlorthalidone vs chlorothiazide, to present a better antihypertensive effect. This effect is even greater when the two substances are combined. In this article, we will try to present the latest findings concerning the efficacy, safety and clinical utility of this combination, as well as its adverse events, in comparison with other widely used therapeutic options.

Genome Wide Association Study Identifies the HMGCS2 Locus to be Associated With Chlorthalidone Induced Glucose Increase in Hypertensive Patients

Background

Thiazide and thiazide‐like diuretics are first‐line medications for treating uncomplicated hypertension. However, their use has been associated with adverse metabolic events, including hyperglycemia and incident diabetes mellitus, with incompletely understood mechanisms. Our goal was to identify genomic variants associated with thiazide‐like diuretic/chlorthalidone‐induced glucose change.

Methods and Results

Genome‐wide analysis of glucose change after treatment with chlorthalidone was performed by race among the white (n=175) and black (n=135) participants from the PEAR‐2 (Pharmacogenomic Evaluation of Antihypertensive Responses‐2). Single‐nucleotide polymorphisms with P<5×10⁻⁸ were further prioritized using in silico analysis based on their expression quantitative trait loci function. Among blacks, an intronic single‐nucleotide polymorphism (rs9943291) in the HMGCS2 was associated with increase in glucose levels following chlorthalidone treatment (ß=12.5; P=4.17×10⁻⁸). G‐allele carriers of HMGCS2 had higher glucose levels (glucose change=+16.29 mg/dL) post chlorthalidone treatment compared with noncarriers of G allele (glucose change=+2.80 mg/dL). This association was successfully replicated in an independent replication cohort of hydrochlorothiazide‐treated participants from the PEAR study (ß=5.54; P=0.023). A meta‐analysis of the 2 studies was performed by race in Meta‐Analysis Helper, where this single‐nucleotide polymorphism, rs9943291, was genome‐wide significant with a meta‐analysis P value of 3.71×10⁻⁸. HMGCS2, a part of the HMG‐CoA synthase family, is important for ketogenesis and cholesterol synthesis pathways that are essential in glucose homeostasis.

Conclusions

These results suggest that HMGCS2 is a promising candidate gene involved in chlorthalidone and Hydrochlorothiazide (HCTZ)‐induced glucose change. This may provide insights into the mechanisms involved in thiazide‐induced hyperglycemia that may ultimately facilitate personalized approaches to antihypertensive selection for hypertension treatment.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00246519 and NCT01203852.

Blood pressure response to metoprolol and chlorthalidone in European and African Americans with hypertension

Despite the availability of many antihypertensive drug classes, half of patients with hypertension have uncontrolled blood pressure (BP). The authors sought to assess the effect of age on BP response in European American and African American patients with hypertension. Clinic BP from the PEAR2 (Pharmacogenomics Evaluation of Antihypertensive Responses 2) study was used to estimate BP responses from baseline following sequential treatment with metoprolol 100 mg twice daily and chlorthalidone 25 mg daily for 8 to 9 weeks each, with a minimum 4-week washout between treatments. BP responses to both drugs were compared in 159 European Americans and 119 African Americans by age with adjustment for baseline BP and sex. European Americans younger than 50 years responded better to metoprolol than chlorthalidone (diastolic BP: -9.6 ± 8.0 vs -5.9 ± 6.8 mm Hg, adjusted P = .003), whereas patients 50 years and older responded better to chlorthalidone than metoprolol (systolic BP: -18.7 ± 13.8 vs -13.6 ± 14.8 mm Hg, adjusted P = .008). African Americans younger than 50 years responded similarly to both drugs, whereas those 50 years and older responded better to chlorthalidone than metoprolol (-17.0 ± 13.2/-9.6 ± 7.5 vs -7.0 ± 18.6/-6.7 ± 9.3 mm Hg, adjusted P<.0001/.008). Therefore, age should be considered when selecting antihypertensive therapy in European and African American populations with hypertension.

Comparison of long-term safety of fixed-dose combinations azilsartan medoxomil/chlorthalidone vs olmesartan medoxomil/hydrochlorothiazide

This 52-week, randomized, open-label study evaluated long-term safety/tolerability of fixed-dose combination azilsartan medoxomil/chlorthalidone (AZL-M/CLD) vs fixed-dose combination olmesartan medoxomil/hydrochlorothiazide (OLM/HCTZ) in patients with essential hypertension (stage 2; clinic systolic blood pressure 160-190 mm Hg). Initial AZL-M/CLD 40/12.5 mg/d (n=418) or OLM/HCTZ 20/12.5 mg/d (n=419) could be uptitrated during weeks 4 to 52 (AZL-M/CLD to 80/25 mg; OLM/HCTZ to 40/25 mg [United States] or 20/25 mg [Europe]) to meet blood pressure targets. Treatment-emergent adverse events/serious adverse events occurred in 78.5%/5.7% of patients taking AZL-M/CLD vs 76.4%/6.2% taking OLM/HCTZ. The most frequent adverse events were dizziness (16.3% vs 12.6%), blood creatinine increase (21.5% vs 8.6%), headache (7.4% vs 11.0%), and nasopharyngitis (12.2% vs 11.5%). Hypokalemia was uncommon (1.0% vs 0.7%). Greater blood pressure reductions with AZL-M/CLD by week 2 were maintained throughout the study, despite less uptitration (32.3% vs 48.9% with OLM/HCTZ). Fixed-dose combination AZL-M/CLD showed an encouraging benefit-risk profile when used per standard clinical practice in a titrate-to-target strategy.

Chlorthalidone Versus Amlodipine for Hypertension in Kidney Transplant Recipients Treated With Tacrolimus: A Randomized Crossover Trial

BACKGROUND

Chlorthalidone is a very effective antihypertensive drug, but it has not been studied prospectively in kidney transplant recipients with hypertension. Recent data indicate that calcineurin inhibitors activate the thiazide-sensitive sodium chloride cotransporter, providing further rationale to test thiazides in this population.

STUDY DESIGN

Randomized noninferiority crossover trial (noninferiority margin, -2.8mmHg).

SETTING & PARTICIPANTS

Hypertensive kidney transplant recipients using tacrolimus (median duration, 2.4 years after transplantation; mean estimated glomerular filtration rate, 63±27 [SD] mL/min/1.73m²; mean systolic blood pressure [SBP], 151±12mmHg).

INTERVENTION

Amlodipine (5-10mg) and chlorthalidone (12.5-25mg) for 8 weeks (separated by 2-week washout).

OUTCOMES

Average daytime (9 am to 9 pm) ambulatory SBP.

MEASUREMENTS

Blood pressure and laboratory parameters.

RESULTS

88 patients underwent ambulatory blood pressure monitoring, of whom 49 (56%) with average daytime SBP>140mmHg were enrolled. 41 patients completed the study. Amlodipine and chlorthalidone both reduced ambulatory SBP after 8 weeks (mean changes of 150±12 to 137±12 [SD] vs 151±12 to 141±13mmHg; effect size, -4.2 [95% CI, -7.3 to 1.1] mmHg). Despite these similar blood pressure responses, chlorthalidone reduced proteinuria by 30% (effect size, -65 [95% CI, -108 to -35] mg/g) and also reduced physician-assessed peripheral edema (22% to 10%; P<0.05 for both). In contrast, chlorthalidone temporarily reduced kidney function and increased both serum uric acid and glycated hemoglobin levels.

LIMITATIONS

Open-label design, short follow-up, per-protocol analysis.

CONCLUSIONS

Chlorthalidone is an antihypertensive drug equally effective as amlodipine after kidney transplantation.

The simultaneous UPLC-MS/MS determination of emerging drug combination; candesartan and chlorthalidone in human plasma and its application

A novel, precise, sensitive and accurate ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method has been developed for the simultaneous determination of a novel drug combination, candesartan (CAN) and chlorthalidone (CHL), in human plasma. Chromatographic separation was achieved on Waters Acquity UPLC BEH C₁₈ (50 × 2.1 mm, 1.7 μm). Mobile phase consisting of 1 mm ammonium acetate in water-acetonitrile (20:80 v/v) was used. The total chromatographic runtime was 1.9 min with retention times for CAN and CHL at 0.7 and 1.1 min respectively. Ionization and detection of analytes and internal standards was performed on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring and negative ionization mode. Quantitation was done to monitor protonated precursor → product ion transition of m/z 439.2 → 309.0 for CAN, 337.0 → 189.8 for CHL and 443.2 → 312.1 for candesartan D4 and 341.0 → 189.8 for chlorthalidone D4. The method was validated over a wide dynamic concentration range of 2.0-540.0 ng/mL for candesartan and 1.0-180.0 ng/mL for chlorthalidone. The validated method was successfully applied for the assay of CAN and CHL in healthy volunteers.

Electrocardiographic measures of left ventricular hypertrophy in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial

Left ventricular hypertrophy (LVH) predicts cardiovascular risk in hypertensive patients. We analyzed baseline/follow-up electrocardiographies in 26,376 Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial participants randomized to amlodipine (A), lisinopril (L), or chlorthalidone (C). Prevalent/incident LVH was examined using continuous and categorical classifications of Cornell voltage. At 2 and 4 years, prevalence of LVH in the C group (5.57%; 6.14%) was not statistically different from A group (2 years: 5.47%; P = .806, 4 years: 6.54%; P = .857) or L group (2 years: 5.64%; P = .857, 4 years: 6.50%; P = .430). Incident LVH followed similarly, with no difference at 2 years for C (2.99%) compared to A (2.57%; P = .173) or L (3.16%; P = .605) and at 4 years (C = 3.52%, A = 3.29%, L = 3.71%; P = .521 C vs. A, P = .618 C vs. L). Mean Cornell voltage decreased comparably across treatment groups (Δ baseline, 2 years = +3 to -27 μV, analysis of variance P = .8612; 4 years = +10 to -17 μV, analysis of variance P = .9692). We conclude that risk reductions associated with C treatment in secondary end points of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial cannot be attributed to differential improvements in electrocardiography LVH.

Effectiveness of Chlorthalidone Plus Amiloride for the Prevention of Hypertension: The PREVER-Prevention Randomized Clinical Trial

BACKGROUND

Prehypertension is associated with higher cardiovascular risk, target organ damage, and incidence of hypertension. The Prevention of Hypertension in Patients with PreHypertension (PREVER-Prevention) trial aimed to evaluate the efficacy and safety of a low-dose diuretic for the prevention of hypertension and end-organ damage.

METHODS AND RESULTS

This randomized, parallel, double-blind, placebo-controlled trial was conducted in 21 Brazilian academic medical centers. Participants with prehypertension who were aged 30 to 70 years and who did not reach optimal blood pressure after 3 months of lifestyle intervention were randomized to a chlorthalidone/amiloride combination pill or placebo and were evaluated every 3 months during 18 months of treatment. The primary outcome was incidence of hypertension. Development or worsening of microalbuminuria, new-onset diabetes mellitus, and reduction of left ventricular mass were secondary outcomes. Participant characteristics were evenly distributed by trial arms. The incidence of hypertension was significantly lower in 372 study participants allocated to diuretics compared with 358 allocated to placebo (hazard ratio 0.56, 95% CI 0.38-0.82), resulting in a cumulative incidence of 11.7% in the diuretic arm versus 19.5% in the placebo arm (P=0.004). Adverse events; levels of blood glucose, glycosylated hemoglobin, creatinine, and microalbuminuria; and incidence of diabetes mellitus were no different between the 2 arms. Left ventricular mass assessed through Sokolow-Lyon voltage and voltage-duration product decreased to a greater extent in participants allocated to diuretic therapy compared with placebo (P=0.02).

CONCLUSIONS

A combination of low-dose chlorthalidone and amiloride effectively reduces the risk of incident hypertension and beneficially affects left ventricular mass in patients with prehypertension.

CLINICAL TRIAL REGISTRATION

URL: http://www.ClinicalTrials.gov, www.ensaiosclinicos.gov. Unique identifiers: NCT00970931, RBR-74rr6s.

Trends in Antihypertensive Medication Use Among US Patients With Resistant Hypertension, 2008 to 2014

Little is known of US trends in antihypertensive drug use for patients with treatment-resistant hypertension (TRH). We analyzed antihypertensive use among patients with TRH (treated with ≥4 antihypertensive drugs concurrently) from July 2008 through December 2014 using Marketscan administrative data. We included adults aged 18 to 65 years, with ≥6 months of continuous enrollment, a hypertension diagnosis, and ≥1 episode of overlapping use of ≥4 antihypertensive drugs; patients with heart failure were excluded. We identified 411 652 unique TRH episodes from 261 652 patients with a mean age of 55.9 years. From 2008 to 2014, we observed an increased prevalence, among TRH episodes, of β-blockers (+6.8% [79% to 85.8%]) and dihydropyridine calcium antagonists (+8.1% [69.1% to 77.2%]), and a decreased prevalence of angiotensin-converting enzyme inhibitors (-12.5% [60.4% to 47.9%]) and nondihydropyridine calcium antagonists (-5.0% [15% to 10%]). The prevalence of most other classes changed by <5% from 2008 to 2014. Thiazide diuretic use was largely unchanged from 2008 to 2014, with hydrochlorothiazide being by far the most prevalent thiazide diuretic; chlorthalidone use increased only modestly (+2.6% [3.8% to 6.4%]). Aldosterone antagonist use increased only modestly (+2.9% [7.3% to 10.2%]). Use of optimal regimens increased steadily (+13.8% [50.8% to 64.6%]) during the study period, whereas combined angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use declined (-11.4% [17.7% to 6.3%]). Our results highlight the persistent infrequent use of recommended therapies in TRH, including spironolactone and chlorthalidone, and suggest a need for better efforts to increase the use of such approaches in light of recent evidence demonstrating their efficacy.

Diuretics for Hypertension: A Review and Update

This review and update focuses on the clinical features of hydrochlorothiazide (HCTZ), the thiazide-like agents chlorthalidone (CTDN) and indapamide (INDAP), potassium-sparing ENaC inhibitors and aldosterone receptor antagonists, and loop diuretics. Diuretics are the second most commonly prescribed class of antihypertensive medication, and thiazide-related diuretics have increased at a rate greater than that of antihypertensive medications as a whole. The latest hypertension guidelines have underscored the importance of diuretics for all patients, but particularly for those with salt-sensitive and resistant hypertension. HCTZ is 4.2-6.2 systolic mm Hg less potent than CTDN, angiotensin-converting enzyme inhibitors, beta blockers, and calcium channel blockers by 24-hour measurements and 5.1mm Hg systolic less potent than INDAP by office measurements. For reducing cardiovascular events (CVEs), HCTZ is less effective than enalapril and amlodipine in randomized trials, and, in network analysis of trials, it is less effective than CTDN and HCTZ-amiloride. Combined with thiazide-type diuretics, potassium-sparing agents decrease ventricular ectopy and reduce the risk for sudden cardiac death relative to thiazide-type diuretics used alone. A recent synthesis of 44 trials has shown that the relative potencies in milligrams among spironolactone (SPIR), amiloride, and eplerenone (EPLER) are approximately from 25 to 10 to 100, respectively, which may be important when SPIR is poorly tolerated. SPIR reduces proteinuria beyond that provided by other renin angiotensin aldosterone inhibitors. EPLER also reduces proteinuria and has beneficial effects on endothelial function. While guidelines often do not differentiate among specific diuretics, this review demonstrates that these distinctions are important for managing hypertension.

Safety and tolerability of azilsartan medoxomil in subjects with essential hypertension: a one-year, phase 3, open-label study

This 56-week phase 3, open-label, treat-to-target study, involving 2 consecutive, non-randomized cohorts, evaluated the safety and tolerability of azilsartan medoxomil (AZL-M) in essential hypertension (mean baseline blood pressure [BP] 152/100 mmHg). All subjects (n = 669) initiated AZL-M 40 mg QD, force-titrated to 80 mg QD at week 4, if tolerated. From week 8, subjects could receive additional medications, starting with chlorthalidone (CLD) 25 mg QD (Cohort 1) or hydrochlorothiazide (HCTZ) 12.5–25 mg QD (Cohort 2), if required, to reach BP targets. Adverse events (AEs) were reported in 75.9% of subjects overall in the two cohorts (73.8% Cohort 1, 78.5% Cohort 2). The most common AEs were dizziness (14.3%), headache (9.9%) and fatigue (7.2%). Transient serum creatinine elevations were more frequent with add-on CLD. Clinic systolic/diastolic BP (observed cases at week 56) decreased by 25.2/18.4 mmHg (Cohort 1) and 24.2/17.9 mmHg (Cohort 2). These results demonstrate that AZL-M is well tolerated over the long term and provides stable BP improvements when used in a treat-to-target BP approach with thiazide-type diuretics.

Evidence-based diuretics: focus on chlorthalidone and indapamide

Thiazide and thiazide-like diuretics are cornerstone treatments for hypertension. However, unlike chlorthalidone (CTD) and indapamide (IDP), hydrochlorothiazide (HCTZ) lacks evidence for reducing morbidity and mortality as monotherapy compared with placebo or control. Despite this fact, HCTZ is prescribed much more frequently than CTD or IDP. We believe that all hypertension guidelines should follow the National Institute for Health and Excellence (NICE) and make IDP and CTD first choice 'thiazide-like diuretics.' This article will focus on the available evidence pertaining to HCTZ versus CTD and IDP. We will review the pharmacological differences between these three diuretics, as well as the clinical trial data and important side effects.

Risk of hyponatremia with diuretics: chlorthalidone versus hydrochlorothiazide

BACKGROUND

Chlorthalidone and hydrochlorothiazide are often considered as interchangeable. However, greater (nighttime) blood pressure reduction, and alleged pleiotropic effects have renewed the interest in chlorthalidone. A recent study showed an increased risk of adverse events with chlorthalidone, including hyponatremia.

METHODS

To investigate differences in risk of hyponatremia between chlorthalidone and hydrochlorothiazide, adjusted for daily dose, we conducted a population-based case-control study within the Dutch IPCI (Integrated Primary Care Information) database. The study population included all subjects ≥18 years without diabetes mellitus, heart failure, liver failure, and malignancy, who were registered in the IPCI database from 1996 to 2011. Cases were subjects with a serum sodium <130 millimoles per liter or hospitalization due to hyponatremia. Controls were matched on practice, age within 5 years, sex, and date of onset.

RESULTS

A total of 1033 cases of hyponatremia were identified. Hyponatremia was more common with chlorthalidone than with hydrochlorothiazide at equal dose per day: adjusted odds ratio was 2.09 (95% confidence interval [CI], 1.13-3.88) for 12.5 milligrams per day and 1.72 (95% CI, 1.15-2.57) for 25 milligrams per day. Risks were not significantly increased with chlorthalidone compared with twice the dose per day of hydrochlorothiazide.

CONCLUSIONS

This is the first study that shows an increased risk of hyponatremia with chlorthalidone relative to hydrochlorothiazide at equal milligram-to-milligram dose per day. The need for a lower dose of chlorthalidone than hydrochlorothiazide to achieve similar blood pressure reduction likely compensates for the increased risk of hyponatremia at equal dose.

Which thiazide to choose as add-on therapy for hypertension?

Combined therapy is required in the majority of patients with hypertension to achieve blood pressure (BP) targets. Although different antihypertensive drugs can be combined, not all combinations are equally effective and safe. In this context, the combination of a renin angiotensin system inhibitor with a diuretic, usually a thiazide, particularly hydrochlorothiazide (HCTZ) or thiazide-like diuretics, such as chlorthalidone or indapamide, is recommended. However, not all diuretics are equal. Although HCTZ, chlorthalidone, and indapamide as add-on therapy effectively reduce BP levels, the majority of studies have obtained greater BP reductions with chlorthalidone or indapamide than with HCTZ. Moreover, there are data showing benefits with chlorthalidone or indapamide beyond BP. Thus, chlorthalidone seems to have pleiotropic effects beyond BP reduction. Moreover, compared with placebo, chlorthalidone has small effects on fasting glucose and total cholesterol, and compared with HCTZ, chlorthalidone achieves significantly lower total cholesterol and low-density lipoprotein cholesterol levels. Similarly, indapamide has demonstrated no negative impact on glucose or lipid metabolism. More importantly, although head-to-head clinical trials comparing the effects of indapamide or chlorthalidone with HCTZ are not available, indirect comparisons and post hoc analyses suggest that the use of chlorthalidone or indapamide is associated with a reduction in cardiovascular events. Despite this, the most frequent diuretic used in clinical practice as add-on therapy for hypertension is HCTZ. The purpose of this review is to update the published data on the efficacy and safety of HCTZ, chlorthalidone, and indapamide as add-on therapy in patients with hypertension.

Spectrophotometric and spectrofluorimetric studies on azilsartan medoxomil and chlorthalidone to be utilized in their determination in pharmaceuticals

The recently approved angiotensin II receptor blocker, azilsartan medoxomil (AZL), was determined spectrophotometrically and spectrofluorimetrically in its combination with chlorthalidone (CLT) in their combined dosage form. The UV-spectrophotometric technique depends on simultaneous measurement of the first derivative spectra for AZL and CLT at 286 and 257 nm, respectively, in methanol. The spectrofluorimetric technique depends on measurement of the fourth derivative of the synchronous spectra intensities of AZL in presence of CLT at 298 nm in methanol. The effects of different solvents on spectrophotometric and spectrofluorimetric responses were studied. For, the spectrofluorimetric study, the effect of pH and micelle-assisted fluorescence enhancement were also studied. Linearity, accuracy, and precision were found to be satisfactory over the concentration ranges of 8–50 μg mL⁻¹ and 2–20 μg mL⁻¹ for AZL and CLT, respectively, in the spectrophotometric method as well as 0.01–0.08 μg mL⁻¹ for AZL in the spectrofluorimetric method. The methods were successfully applied for the determination of the studied drugs in their co-formulated tablets. The developed methods are inexpensive and simple for the quality control and routine analysis of the cited drugs in bulk and in pharmaceuticals.

Physician underutilization of effective medications for resistant hypertension at office visits in the United States: NAMCS 2006-2010

BACKGROUND

The American Heart Association (AHA) published guidelines for treatment of resistant hypertension in 2008 recommending use of thiazide diuretics (particularly chlorthalidone), aldosterone antagonists, and fixed-dose combination medications, but it is unclear the extent to which these guidelines are being followed.

OBJECTIVE

To describe trends in physician use of recommended medications for resistant hypertension and assess variations in medication use based on geography, physician specialty and patient characteristics.

DESIGN

Cross-sectional analysis using the National Ambulatory Medical Care Survey from 2006 to 2010.

STUDY SAMPLE

We analyzed visits of hypertension patients to family physicians, general internists, and cardiologists. Resistant hypertension was defined as concurrent use of ≥ 4 classes of blood pressure (BP) medications or elevated BP despite the use of ≥ 3 medications. Pregnant patients and visits with diagnosed heart failure or end-stage renal disease were excluded.

MAIN OUTCOME

Use of AHA-recommended medications for management of resistant hypertension.

RESULTS

Of 19,500 patient visits with hypertension, 1,567 or 7.1 % CI (6.6-7.7 %) met criteria for resistant hypertension. Thiazide diuretic use was reported in 58.9 % of visits pre-guidelines vs. 54.8 % post-guidelines (p = 0.37). Use of aldosterone antagonists was low and also did not change significantly after guideline publication (3.1 % vs. 4.5 %, p = 0.27). Fixed-dose combinations use was 42.0 % before and 37 % after guideline publication (p = 0.29). Each 10-year increase in patient age was associated with lower thiazide use (OR 0.87, CI 0.77-0.97), as was presence of comorbid ischemic heart disease (OR 0.62, CI 0.41-0.94). Medication use did not vary by geography or physician specialty.

CONCLUSION

Use of AHA-recommended medications for resistant hypertension remains low after publication of guidelines. Healthcare systems should encourage more frequent prescribing of these medications to improve care in this high-risk population.

Parallel-group 8-week study on chlorthalidone effects in hypertensives with low kidney function

Short-term effects of chlorthalidone are unknown in low kidney function. The effects of 8-week treatment with 25-mg chlorthalidone on the top of ongoing treatment were compared between control hypertensives and low kidney function hypertensives as assessed by estimated glomerular filtration rate <60 mL/min×1.73 m(2). Screening period consisted of 2 visits for patient selection and pretreatment laboratory evaluations (baseline). Inclusion criteria were uncontrolled hypertension on nondiuretic antihypertensive treatment. Exclusion criteria were chlorthalidone contraindications, refused consent, treatment with >3 antihypertensive drugs, severe hypertension, severe comorbidities, unreliable estimated glomerular filtration rate. Treatment period consisted of 5 visits (weeks 1, 2, 4, 6, and 8). Post-treatment laboratory evaluations were performed 3 to 4 days before week-8 visit. The 2 groups differed for baseline estimated glomerular filtration rate (low kidney function and control: n=60 and 60; mean, 39 and 76; range, 15-59 and 60-104) but not for sex, age, and baseline blood pressure. Week-8 blood pressure changes were a decrease in both groups (low kidney function and control: systolic pressure, -20 and -23; 95% confidence interval, -22/-18 and -26/-19; diastolic pressure, -9 and -10, -11/-7, and -13/-8) without significant between-group differences. Incidence of adverse events was similar in the 2 groups (15.0% and 16.7%). Baseline estimated glomerular filtration rate did not predict blood pressure changes and adverse events in either groups (P>0.6). In both groups, post-treatment changes were a decrease for estimated glomerular filtration rate and serum potassium, an increase for serum uric acid (P<0.01). Data show that short-term chlorthalidone effects were not reduced in hypertensives with low kidney function.

Management of patients with resistant hypertension: current treatment options

Resistant hypertension (RHTN) is an increasingly common clinical problem that is often heterogeneous in etiology, risk factors, and comorbidities. It is defined as uncontrolled blood pressure on optimal doses of three antihypertensive agents, ideally one being a diuretic. The definition also includes controlled hypertension with use of four or more antihypertensive agents. Recent observational studies have advanced the characterization of patients with RHTN. Patients with RHTN have higher rates of cardiovascular events and mortality compared with patients with more easily controlled hypertension. Secondary causes of hypertension, including obstructive sleep apnea, primary aldosteronism, renovascular disease, are common in patients with RHTN and often coexist in the same patient. In addition, RHTN is often complicated by metabolic abnormalities. Patients with RHTN require a thorough evaluation to confirm the diagnosis and optimize treatment, which typically includes a combination of lifestyle adjustments, and pharmacologic and interventional treatment. Combination therapy including a diuretic, a long-acting calcium channel blocker, an angiotensin-converting enzyme inhibitor, a beta blocker, and a mineralocorticoid receptor antagonist where warranted is the classic regimen for patients with treatment-resistant hypertension. Mineralocorticoid receptor antagonists like spironolactone or eplerenone have been shown to be efficacious in patients with RHTN, heart failure, chronic kidney disease, and primary aldosteronism. Novel interventional therapies, including baroreflex activation and renal denervation, have shown that both of these methods may be used to lower blood pressure safely, thereby providing exciting and promising new options to treat RHTN.

Evaluation of the efficacy and safety of a hydrochlorothiazide to chlorthalidone medication change in veterans with hypertension

BACKGROUND

There are few data available examining the clinical impact of switching patients from hydrochlorothiazide (HCTZ) to chlorthalidone for blood pressure management.

OBJECTIVES

The goal of this study was to compare within-patient clinic blood pressure readings, serum electrolyte levels, and renal function markers before and after a medication change from HCTZ to chlorthalidone in a veteran population.

METHODS

This was a retrospective, pre- and postmeasure, self-controlled study. Veterans Affairs Ann Arbor Healthcare System patients switched from HCTZ to chlorthalidone between January 1, 2001, and January 31, 2012, who had at least 1 follow-up clinic blood pressure reading recorded between 2 and 8 weeks from the date of the medication change were included in the study. Mean pre- and postmeasure values for systolic and diastolic clinic blood pressures, serum potassium, serum sodium, serum calcium, serum creatinine, and blood urea nitrogen were compared by using a 2-tailed, paired t test with a significance level (α) of 0.05.

RESULTS

Of the 40 patients included in the study 95% were male, 65% were white, and the mean age was 64.9 (10.8) years. Both mean systolic (-15.8 mm Hg [95% CI, 8.9 to 22.6], P < 0.0001) and mean diastolic (-4.2 mm Hg [95% CI, 1.5 to 6.9], P = 0.0035) blood pressures showed statistically and clinically significant reductions after the medication change. A statistically significant decrease in mean sodium (-1.1 mmol/L [95% CI, 0.4 to 1.9], P = 0.003) and an increase in mean serum creatinine (0.06 mg/dL [95% CI, -0.09 to -0.02], P = 0.002) was observed; however, these changes may not be viewed as clinically significant by many practitioners. No statistically significant changes were observed in any of the other outcomes examined. Most patients (38 of 40) were taking at least 1 additional antihypertensive agent; 73% of patients were using ≥ 3 antihypertensive agents at the time of the medication change.

CONCLUSIONS

In patients with hypertension already taking HCTZ, switching to chlorthalidone seems to further reduce systolic and diastolic blood pressures without any clinically significant changes in renal function or electrolyte levels.