The short-term and long-term effects of tolvaptan in patients with heart failure: a meta-analysis of randomized controlled trials

Tolvaptan for water retention in heart failure: a systematic review

OBJECTIVE

The purpose of this systematic review is to collect, appraise, and synthesize existing evidence from systematic reviews and meta-analyses (SRs/MAs) on the effectiveness of tolvaptan for water retention in heart failure.

METHODS

A comprehensive literature search was performed on PubMed, EMBASE, web of science, Cochrane reviews for SRs/Mas published between the databases' establishment to November 17, 2021. All the records were managed with Endnote 20. Standardized forms were used to extract data. Revman 5.3 was used to make forest plots to show the characteristics of outcomes. The methodological and evidence quality were respectively evaluated by AMSTAR-2 (A MeaSurement Tool to Assess systematic Reviews 2) and GRADE (Grading of Recommendation of Assessment, Development, and Evaluation) system.

RESULTS

A total of 9 SRs/Mas between 2015 to 2020 met inclusion criteria. Serum sodium concentration and urine output were considered as primary outcomes and body weight change and all-cause mortality as second outcomes. Through conducting forest plots, it appeared that tolvaptan brought more positive effect than conventional therapies. It was pessimistic when it comes to the quality of the 9 studies. all the 9 articles were rated as low-quality because AMSTAR 2 evaluation showed that they each had at least one critical item (items 2, 4, 7, 9, 11, 13 and 15) defect. Besides, every article had a few non-critical item defects too. The result of GRADE assessment was not optimistic, so the overall quality of the evidences was low as well.

CONCLUSION

Tolvaptan can be recommended for water retention in HF patients, but more evidence is needed.

The management of acute and chronic hyponatraemia

Hyponatraemia is the most common electrolyte abnormality encountered in clinical practice; despite this, the work-up and management of hyponatraemia remain suboptimal and varies among different specialist groups. The majority of data comparing hyponatraemia treatments have been observational, up until recently. The past two years have seen the publication of several randomised control trials investigating hyponatraemia treatments, both for chronic and acute hyponatraemia. In this article, we aim to provide a background to the physiology, cause and impact of hyponatraemia and summarise the most recent data on treatments for acute and chronic hyponatraemia, highlighting their efficacy, tolerability and adverse effects.

Cost-Effectiveness of long-term tolvaptan administration for chronic heart failure treatment in Japan

BACKGROUND

Tolvaptan (TLV) is effective for acute heart failure (HF) with congestion, but its long-term administration in patients with chronic HF (CHF) remains controversial. Moreover, the cost-effectiveness of TLV for CHF treatment has not yet been investigated. Thus, we sought to validate the cost-effectiveness of TLV for CHF treatment in Japan.

METHODS

A Markov model was developed to compare total costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) between long-term TLV strategy and the standard strategy using furosemide for CHF. The target population included 75-year-old patients with CHF. The effectiveness of the TLV strategy for CHF treatment was determined based on a systematic review and meta-analysis. We used a 10-year horizon, with sensitivity analyses for significant variables and a scenario analysis for patients with CHF receiving high-dose furosemide (≥60 mg per day).

RESULTS

In the base case analysis, the total cost of the long-term TLV strategy was higher than that of the standard strategy (\3,243,779 vs. \1,179,964). The total QALYs of the long-term TLV strategy were lower than those of the standard strategy (4.52 vs 4.59). Thus, a standard TLV prescription for CHF treatment has no clinical or economic benefit. In the scenario analysis (i.e. in patients with CHF receiving high-dose furosemide), the long-term TLV strategy was more effective (total QALYs, 5.10 vs. 4.41) but more expensive (total costs, \3,540,558 vs. \1,272,208) than the standard strategy. The ICER of the TLV strategy against the standard strategy (¥3,289,579/QALY) was below the willingness-to-pay of \5,000,000, which suggests that the long-term TLV strategy is cost-effective relative to the standard strategy in patients with CHF receiving high-dose furosemide.

CONCLUSIONS

Long-term TLV administration did not provide a clear benefit for all patients with CHF. However, this treatment strategy may be a cost-effective therapeutic option for patients who require high-dose furosemide.

The benefits of sacubitril-valsartan in patients with acute myocardial infarction: a systematic review and meta-analysis

AIMS

We aimed to investigate whether sacubitril-valsartan could further improve the prognosis, cardiac function, and left ventricular (LV) remodelling in patients following acute myocardial infarction (AMI).

METHODS AND RESULTS

We searched the PubMed, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI) from inception to 10 May 2021 to identify potential articles. Randomized controlled trials (RCTs) meeting the inclusion criteria were included and analysed. Thirteen RCTs, covering 1358 patients, were analysed. Compared with angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor blockers (ARB), sacubitril-valsartan did not significantly reduced the cardiovascular mortality [risk ratio (RR) 0.65, 95% confidence interval (CI) 0.22 to 1.93, P = 0.434] and the rate of myocardial reinfarction (RR 0.65, 95% CI 0.29 to 1.46, P = 0.295) of patients following AMI, but the rate of hospitalization for heart failure (HF) (RR 0.48, 95% CI 0.35 to 0.66, P < 0.001) and the change of LV ejection fraction (LVEF) [weighted mean difference (WMD) 5.49, 95% CI 3.62 to 7.36, P < 0.001] were obviously improved. The N-terminal pro-brain natriuretic peptide (NT-ProBNP) level (WMD -310.23, 95% CI -385.89 to -234.57, P < 0.001) and the LV end-diastolic dimension (LVEDD) (WMD -3.16, 95% CI -4.59 to -1.73, P < 0.001) were also significantly lower in sacubitril-valsartan group than in ACEI/ARB group. Regarding safety, sacubitril-valsartan did not increase the risk of hypotension, hyperkalaemia, angioedema, and cough.

CONCLUSIONS

This meta-analysis suggests that early administration of sacubitril-valsartan may be superior to conventional ACEI/ARB to decrease the risk of hospitalization for HF, improve the cardiac function, and reverse the LV remodelling in patients following AMI.

Renoprotection by long-term low-dose tolvaptan in patients with heart failure and hyponatremia

AIMS

In previous randomized controlled trials, the use of tolvaptan (TLV) at a fixed dose of 30 mg/day for 1 year did not provide renal benefits in patients with heart failure (HF). This retrospective, cohort study examined the renoprotective effects of long-term, flexible-dose, and lower-dose TLV use.

METHODS AND RESULTS

Tolvaptan users were defined as patients receiving TLV for at least 180 consecutive days or those who continued it until death, any cardiac events, or renal replacement therapy even if it was taken for <180 days. Of a total of 584 HF patients, 78 TLV users were identified. The median age, baseline B-type natriuretic peptide, and estimated glomerular filtration rate (eGFR) were 71 years, 243 pg/mL, and 54 mL/min/1.73 m² , respectively. During follow-up (median, 461 days), TLV use (median average dose, 7.5 mg/day) was associated with frequent dose reductions of loop diuretics (incidence rate ratio [IRR], 1.5; 95% confidence interval [CI], 1.1-2.2), particularly in patients with serum sodium ≤135 mEq/L (IRR, 2.9; 95% CI, 1.5-5.7) (P_interaction  = 0.04). In a mixed effects model, propensity score (PS)-matched TLV users had higher eGFRs over time than PS-matched never-users (P < 0.01). The entire cohort analyses (N = 584) yielded similar results. The renal benefit of TLV in terms of annualized eGFR slope was more pronounced in patients with lower sodium levels (P_interaction  = 0.03). This effect modification was extinguished when patients who underwent a loop diuretic dose reduction during the follow-up period were excluded from the analysis.

CONCLUSIONS

Long-term, flexible-dose, and low-dose TLV use was associated with better renal function, particularly in hyponatremic HF, possibly due to its loop diuretic dose-sparing effect in the long term.

Usefulness of Tolvaptan for the Postoperative Control After Kidney Transplantation in a Patient With Cardiac Hypofunction: A Case Report

BACKGROUND

Kidney transplantation in patients with cardiac hypofunction is challenging. Even if the surgery is successfully performed, these patients may suffer from low output cardiac function. We report the case of a patient with severe cardiac hypofunction who developed heart failure (HF) complicated with low output cardiac function, which markedly improved after the administration of tolvaptan, after successful living kidney transplantation.

CASE PRESENTATION

A 70-year-old man was diagnosed with chronic renal failure of unknown etiology 4 years previously, for which hemodialysis was initiated. Three years previously, percutaneous coronary intervention was performed because of acute myocardial infarction. Since then, he had been hospitalized for the control of HF. He was referred to our department because he wished to undergo kidney transplantation. We decided to perform the transplantation after determining that he could tolerate the operation. On postoperative day 6, however, his urine discharge volume suddenly declined, leading to an increase in his body weight despite administration of an adequate amount of furosemide, and he was diagnosed with acute HF. The patient's condition markedly improved after the introduction of tolvaptan.

CONCLUSION

To our knowledge, this is the first report of improvement in postoperative HF after tolvaptan administration. Although numerous kidney transplantations have been performed at our institute, it is relatively rare that we decide to operate in a patient with severe cardiac hypofunction.

Old and New Drugs for Treatment of Advanced Heart Failure

BACKGROUND

Advanced heart failure (HF) is a progressive disease with high mortality and limited medical therapeutic options. Long-term mechanical circulatory support and heart transplantation remain goldstandard treatments for these patients; however, access to these therapies is limited by the advanced age and multiple comorbidities of affected patients, as well as by the limited number of organs available.

METHODS

Traditional and new drugs available for the treatment of advanced HF have been researched.

RESULTS

To date, the cornerstone for the treatment of patients with advanced HF remains water restriction, intravenous loop diuretic therapy and inotropic support. However, many patients with advanced HF experience loop diuretics resistance and alternative therapeutic strategies to overcome this problem have been developed, including sequential nephron blockade or use of the hypertonic saline solution in combination with high-doses of furosemide. As classic inotropes augment myocardial oxygen consumption, new promising drugs have been introduced, including levosimendan, istaroxime and omecamtiv mecarbil. However, pharmacological agents still remain mainly short-term or palliative options in patients with acute decompensation or excluded from mechanical therapy.

CONCLUSION

Traditional drugs, especially when administered in combination, and new medicaments represent important therapeutic options in advanced HF. However, their impact on prognosis remains unclear. Large trials are necessary to clarify their therapeutic potential and prognostic role in these fragile patients.

Hemodynamic and Hormonal Effects of Tolvaptan for Heart Failure

Tolvaptan (TLV) is a diuretic agent administrated for heart failure (HF) only in Japan. Many clinical findings have been obtained from the accumulation of clinical experience, and the administration of TLV reportedly avoids causing a reduction in the renal function. In addition, TLV has been reported to exert effects other than diuresis. The early start of TLV after hospitalization shortens the length of the hospital stay, and continuous TLV after discharge extends the period until re-hospitalization of HF patients. TLV is thought to function via vasopressin V2 receptor antagonism. However, no significant differences in the long-term prognosis were noted between the group using TLV and not using TLV in the Endovascular Valve Edge-to-Edge Repair Study (EVEREST) trial, and effects other than diuresis are not useful for all HF patients. Therefore, it is necessary to identify patients who may experience effects other than diuresis with TLV administration. The accumulation of more patients and findings from further large-scale clinical trials will be necessary in order to clarify these points.

Correction of Hyponatremia May Be a Treatment Stratification Biomarker: A Two-Stage Systematic Review and Meta-Analysis

Changes in serum sodium concentration ([Na⁺]_serum) can permit evaluation of the treatment effect of vasopressin antagonists (vaptans) in patients with worsening heart failure (HF) or cirrhotic ascites; that is, they may act as a treatment stratification biomarker. A two-stage systematic review and meta-analysis were carried out and contextualized by experts in fluid resuscitation and translational pharmacology (registration ID in the International Prospective Register of Systematic Reviews (PROSPERO): CRD42017051440). Meta-analysis of aggregated dichotomous outcomes was performed. Pooled estimates for correction of hyponatremia (normalization or an increase in [Na⁺]_serum of at least 3–5 mEq/L) under treatment with vaptans (Stage 1) and for clinical outcomes in both worsening HF (rehospitalization and/or death) and cirrhotic ascites (ascites worsening) when correction of hyponatremia is achieved (Stage 2) were calculated. The body of evidence was assessed. Correction of hyponatremia was achieved under vaptans (odds ratio (OR)/95% confidence interval (95% CI)/I²/number of studies (n): 7.48/4.95–11.30/58%/15). Clinical outcomes in both worsening HF and cirrhotic ascites improved when correction of hyponatremia was achieved (OR/95% CI/I²/n: 0.51/0.26–0.99/52%/3). Despite the appropriateness of the study design, however, there are too few trials to consider that correction of hyponatremia is a treatment stratification biomarker. Patients with worsening HF or with cirrhotic ascites needing treatment with vaptans, have better clinical outcomes when correction of hyponatremia is achieved. However, the evidence base needs to be enlarged to propose formally correction of hyponatremia as a new treatment stratification biomarker. Markers for use with drugs are needed to improve outcomes related to the use of medicines.

Pharmacological management of hyponatremia

INTRODUCTION

Hyponatremia is the most common electrolyte disorder with a prevalence of up to 30% in hospitalized patients. Furthermore, it is associated with increased morbidity and mortality.

AREAS COVERED

This review discusses the efficacy and side effects of the currently available treatment options for hyponatremia and the differences in the pharmacological approach between the European and USA guidelines. Additionally, the authors provide their expert perspectives on current treatment strategies and what they expect from this field in the future.

EXPERT OPINION

Several pharmacological options are available for the treatment of hyponatremia, but data from trials examining and comparing these treatments are missing. Regarding chronic hyponatremia, the role of vaptans should be further analyzed, focusing on comparisons with other active treatments on patient-relevant outcomes and not only on serum sodium concentration. Clinicians should be cautious to an overly rapid increase in serum sodium levels with all available treatment strategies. Finally, it is important to ascertain whether correction of serum sodium levels improves mortality in hyponatremic patients.

Hyponatremia Predicts Poor Outcomes in Patients With Chronic Kidney Disease Undergoing Heart Operation

BACKGROUND

Preoperative hyponatremia adversely affects outcomes of cardiothoracic operation. However, in patients with chronic kidney disease, the association of sodium levels on postoperative events has never been evaluated. We investigated the impact of preoperative hyponatremia on outcomes after cardiac operation in patients with non-dialysis-dependent chronic kidney disease. Primary end points were operative mortality and acute kidney injury that required dialysis. Secondary end points were major infection and long-term survival.

METHODS

The study is observational and includes all patients with stage III to IV chronic kidney disease (non-dialysis) undergoing cardiac operation between February 2000 and January 2016. Patients were stratified into two groups by preoperative sodium levels: sodium less than 135 mEq/L and sodium of 135 mEq/L or more.

RESULTS

There were 1,008 patients (mean estimated glomerular filtration rate [GFR]: 43 ± 14 mL • min^-1 • 1.73 m^-2) with 92 patients (9%) in the low-sodium group. Patients with low sodium had higher operative mortality (p = 0.0004), need for new dialysis (p = 0.0008), and infection (p = 0.002). Predictors of operative mortality were European System for Cardiac Operative Risk Evaluation (EuroSCORE) (hazard ratio [HR] 1.03. 95% confidence interval [CI]: 1.02 to 1.05, p < 0.0001), decreasing values of sodium (HR 1.14. 95% CI: 1.07 to 1.2, p = 0.0002), and decreasing values of GFR (HR 1.01, 95% CI: 1.003 to 1.03, p = 0.007). Sodium less than 135 mEq/L was independently associated with increased need for dialysis (HR 1.3, 95% CI: 1.1 to 1.7, p = 0.0008). By linear regression, decreasing values of preoperative sodium were proportionate to the incidence of operative mortality (p < 0.0001) and need for dialysis (p < 0.0001).

CONCLUSIONS

Preoperative hyponatremia is a predictor of increased mortality and other adverse events in patients with non-dialysis-dependent chronic kidney disease undergoing cardiac operation. These findings are similar to those in hyponatremic patients without kidney disease.

Tolvaptan for Heart Failure in Chronic Kidney Disease Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Heart failure (HF) is frequently associated with renal impairment. Tolvaptan is reported to be effective in treating congestion in HF without significant electrolyte loss compared to conventional diuretics. However, the safety and efficacy of its use in patients with chronic kidney disease (CKD) is uncertain. This systematic review and meta-analysis evaluated the efficacy and safety outcomes of tolvaptan for HF management in patients with CKD, with a focus at a physiologic basis related to safety.

METHODS

We searched for observational studies and randomised clinical trials (RCTs) that assessed the effects of tolvaptan against placebo or standard care in adult patients with HF and CKD. Our protocol was registered with PROSPERO (number CRD42017052775).

RESULTS

Seventeen studies were included in the qualitative review and six in the meta-analysis involving 1597 patients. Tolvaptan was associated with an increase in sodium concentration. No significant differences in change of eGFR and serum creatinine were found between tolvaptan and control groups. Urine flow rate appears to increase significantly with tolvaptan compared to baseline (p<0.0001). The meta-analysis demonstrated no heterogeneity between studies but the possibility of publication bias due to incomplete reporting in excluded studies and lack of RCTs.

CONCLUSIONS

The safety profile of tolvaptan appears acceptable for patients with HF and CKD. There is evidence for an improvement in serum sodium and reduction in body water without deterioration in renal function. Further research is needed to elucidate the long-term benefits of tolvaptan as an adjunct or alternative to diuretics in such patients.

Effects and safety of oral tolvaptan in patients with congestive heart failure: A systematic review and network meta-analysis

AIMS

Several studies reported treatment benefits of tolvaptan in patients with congestive heart failure (CHF). However, the optimal dosage remains unclear. We aimed to compare different dosage of tolvaptan to determine the optimal dosage in terms of the efficacy and safety.

METHODS

We searched MEDLINE, PubMed, EMBASE, Cochrane CENTRAL and ClinicalTrials.gov through Aug 31, 2016. Randomized controlled trials (RCTs) comparing tolvaptan of different dosages or to placebo in patients with CHF were included. We used network meta-analysis to look for the optimal dosage in terms of effectiveness and safety. Urine output, body weight change and change in serum sodium were the main outcomes of efficacy. Adverse effects were the secondary outcomes. Quality was assessed by Cochrane risk-of-bias tool.

RESULTS

Twelve RCTs reporting 14 articles with 5793 patients (mean age, 65.7 ± 11.9 years; 73.7% man) were included. Compared with placebo, the tolvaptan 30 mg had similar effects to tolvaptan 45-90 mg in terms of urine output (mean difference [MD] 2.03 liter; 95% confidence interval [CI] 1.3 to 2.71), body weight change (MD -1.12 kg; 95% CI -1.37 to -0.88) and change in serum sodium (MD 3.06 meq/L; 95% CI 2.43 to 3.68). Compared with placebo, tolvaptan of different dosage showed a non-significant higher risk of adverse effects.

CONCLUSIONS

These findings suggest that tolvaptan 30 mg and 45 mg may be the optimum dosage for CHF patients, because of its ability to provide favourable clinical results without greater adverse effects. However, tolvaptan is not beneficial for reducing all-cause mortality in CHF patients.

Experience with long-term administration of tolvaptan to patients with acute decompensated heart failure

Tolvaptan (TLV) is an oral selective vasopressin type 2 receptor antagonist. Long-term use of TLV is not recommended in patients with heart failure (HF) if fluid retention disappears and/or body weight is within the target range. However, some patients require long-term use of TLV. The current study investigated the efficacy and safety of long-term use of TLV. Subjects were 258 consecutive patients with HF who received TLV during hospitalization from January 2011 to March 2015. The rate of continuing administration of TLV was evaluated. Moreover, the one-year mortality rate and rate of re-hospitalization either with or without TLV were investigated. Results at discharge and one year later were compared for patients who continued to receive TLV one year after discharge. Oral concomitant medications, blood pressures, heart rate, blood tests, chest X-ray and transthoracic echocardiography were investigated. In-hospital and one-year mortality rates were 15.9% and 27.8%, respectively. Moreover, the mortality rate and/or rate of re-hospitalization within one year was 54.4%. The rate of re-hospitalization for HF was significantly higher in patients who continued to receive TLV after discharge compared to patients who ceased receiving TLV after discharge (p < 0.001). However, the subjects who continued to receive TLV for up to one year after discharge tended to have a longer duration until re-hospitalization for HF and significantly decreased brain natriuretic peptide levels (577.6 ± 528.5 pg/mL to 397.3 ± 365.8 pg/mL, p = 0.015). Long-term use of TLV might delay re-hospitalization for HF in patients with severe HF. Large-scale clinical studies are necessary to verify these results.

Cardiorenal Syndrome: Role of Arginine Vasopressin and Vaptans in Heart Failure

Heart and kidney failure continued to be of increasing prevalence in today's society, and their comorbidity has synergistic effect on the morbidity and mortality of patients. Cardiorenal syndrome (CRS) is a complex disease with multifactorial pathophysiology. Better understanding of this pathophysiological network is crucial for the successful intervention to prevent advancement of the disease process. One of the major factors in this process is neurohormonal activation, predominantly involving renin-angiotensin-aldosterone system (RAAS) and arginine vasopressin (AVP). Heart failure causes reduced cardiac output/cardiac index (CO/CI) and fall in renal perfusion pressures resulting in activation of baroreceptors and RAAS, respectively. Activated baroreceptors and RAAS stimulate the release of AVP (non-osmotic pathway), which acts on V₂ receptors located in the renal collecting ducts, causing fluid retention and deterioration of heart failure. Effective blockade of AVP action on V₂ receptors has emerged as a potential treatment option in volume overload conditions especially in the setting of hyponatremia. Vasopressin receptor antagonists (VRAs), such as vaptans, are potent aquaretics causing electrolyte-free water diuresis without significant electrolyte abnormalities. Vaptans are useful in hypervolemic hyponatremic conditions like heart failure and liver cirrhosis, and euvolemic hyponatremic conditions like syndrome of inappropriate anti-diuretic hormone secretion. Tolvaptan and conivaptan are pharmaceutical agents that are available for the treatment of these conditions.

Effects of Tolvaptan in patients with acute heart failure: a systematic review and meta-analysis

Background

Acute heart failure, which requires urgent evaluation and treatment, is a leading cause for admission to the emergency department. The aim of this meta-analysis was to evaluate the effects of tolvaptan on acute heart failure and compare them with the effects of conventional therapy or placebo.

Methods

The electronic databases PubMed, EMBASE, and the Cochrane Controlled Trial registry were searched from their starting dates to October 24, 2016. Two authors independently read the trials and extracted related information from the included studies. We used fixed-effects or random-effects models to assess the overall combined risk estimates according to I² statistics. Analysis to determine sensitivity and publication bias was conducted.

Results

Six randomised controlled trials from eight articles, with a total of 746 patients, were included for analysis. Compared with the control, tolvaptan reduced body weight in two days (WMD 1.35; 95% CI 0.75 to 1.96), elevated sodium level in two days (WMD 2.33; 95% CI 1.08 to 3.57) and five days (WMD 1.57; 95% CI 0.04 to 3.09), and ameliorated symptoms of dyspnoea (RR 0.82; 95% CI 0.71–0.95). However, tolvaptan did not improve long-term (RR 1.04; 95% CI 0.66–1.62) or short-term all-cause mortality (RR 0.89; 95% CI 0.45–1.76), incidence of clinical events (worsening heart failure, RR 0.75; 95% CI 0.50–1.12 and worsening renal function, RR 0.97; 95% CI 0.75–1.27), and length of hospital stay in patients (WMD 0.14; 95% CI -0.29 to 2.38) with acute heart failure.

Conclusion

Tolvaptan can decrease body weight, increase serum sodium level, and ameliorate some of the congestion symptoms in patients with acute heart failure, which may help avoid the overdose of loop diuretics, especially in patients with renal dysfunction.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-017-0598-y) contains supplementary material, which is available to authorized users.

Use of tolvaptan vs. furosemide in older patients with heart failure : Meta-analysis of randomized controlled trials

BACKGROUND

It is not known whether older patients with acute heart failure (HF) receiving tolvaptan have decreased mortality rates and a better long-term prognosis than patients who receive furosemide. We conducted a systematic review of randomized controlled trials (RCTs) to address this issue.

METHODS

The Medline, Embase, and Cochrane Library databases were searched for English-language RCTs published before September 2016 comparing tolvaptan with furosemide treatment in older patients (>65 years old) after acute HF. The primary outcomes assessed were 6‑month all-cause mortality and worsening renal function (WRF); the secondary outcomes were electrolyte disorders, hospital readmissions, and adverse events.

RESULTS

Out of 669 citations, six RCTs met the inclusion criteria for this meta-analysis. There was a significant decrease in WRF (relative risk [RR] = 0.67, 95% confidence interval [CI] = 0.52-0.86, p = 0.002) and in the hospitalization period (mean difference [MD] = -1.86, 95% CI = -3.70--0.02, p = 0.05), as well as a significant increase in urine volume within 3 days of tolvaptan administration (MD = 1.59, 95% CI = 1.41-1.76, p < 0.00001). There were significant differences in creatinine levels between subgroups (MD = 0.33, 95% CI = 0.14-0.52, p = 0.0006). However, for the outcome of 6‑month all-cause mortality (RR = 0.56, 95% CI = 0.29-1.06, p = 0.07), there was no significant difference among all subgroups. There were significant differences in serum sodium concentration (MD = 0.68, 95% CI = 0.02-1.34, p = 0.04) but no significant changes in systolic blood pressure (MD = 3.57, 95% CI = -2.33-9.47, p = 0.24) between groups.

CONCLUSION

In older patients, tolvaptan relieves WRF, reduces the hospitalization period, and increases urine volume without significant effects on blood pressure. However, surprisingly, the use of tolvaptan did not influence 6‑month all-cause mortality.

The Efficacy and Safety of Tolvaptan in Patients with Hyponatremia: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND AND OBJECTIVES

Comprehensive evaluations regarding the benefits of tolvaptan in the treatment of hyponatremia are lacking. The objective of this meta-analysis was to assess the efficacy and safety of tolvaptan in patients with hyponatremia.

METHODS

Pertinent studies were identified by searching PubMed, EMBASE, Web of Science, and the Cochrane Library for articles published between their respective inception dates and 31 April 2016. Summary relative risks (RRs) or weighted mean differences (WMDs) with their 95 % confidence intervals (CIs) were calculated using fixed-effects or randomized-effects models, depending on the degree of heterogeneity noted among the studies included in the analysis.

RESULTS

Eleven articles comprising 5209 patients were ultimately included in the analysis. Our pooled results showed that tolvaptan was more effective than control with respect to increasing serum sodium concentrations (WMD = 3.99 mEq/L), 95 % CI 2.80-5.19, Z = 6.56, P < 0.001), improving serum sodium correction rates (RR = 3.35, 95 % CI 1.93-5.82, Z = 4.31, P < 0.001), improving 24-h urine output (WMD = 987.64 mL, 95 % CI 850.71-1124.57, Z = 14.14, P < 0.001), and improving net fluid balance (WMD = 795.97 mL, 95 % CI 418.56-1173.38, Z = 4.13, P < 0.001). Tolvaptan treatment also resulted in increased incidences of adverse events compared with control treatment (RR = 1.05, 95 % CI 1.02-1.07, Z = 3.83, P < 0.001). These events included dry mouth (RR = 2.38, 95 % CI 1.41-4.04, Z = 3.23, P = 0.001), thirst (RR = 3.85, 95 % CI 1.96-7.57, Z = 3.92, P < 0.001), pollakiuria (RR = 2.47, 95 % CI 1.41-4.33, Z = 3.16, P = 0.002), and overly rapid hyponatremia correction (RR = 8.43, 95 % CI 1.06-66.96, Z = 2.02, P = 0.04). No significant differences in all-cause mortality (RR = 0.99, 95 % CI 0.90-1.10, Z = 0.17, P = 0.86), serious adverse event rate (RR = 1.01, 95 % CI 0.80-1.29, Z = 0.11, P = 0.92), systolic blood pressure (WMD = 0.1 mmHg, 95 % CI -1.04 to 1.23, Z = 0.17, P = 0.87), or heart rate (WMD = -0.16 bpm, 95 % CI -1.14 to 0.82, Z = 0.31, P = 0.76) were noted between the two groups, based on the results of our meta-analysis.

CONCLUSION

The results of this meta-analysis suggest that tolvaptan can increase serum sodium concentrations, serum sodium correction rates, 24-h urine output, net fluid balance, and total adverse event rates without significantly decreasing all-cause mortality rates or increasing serious adverse event rates in patients with hyponatremia.

Preoperative Statin Treatment for the Prevention of Acute Kidney Injury in Patients Undergoing Cardiac Surgery: A Meta-Analysis of Randomised Controlled Trials

BACKGROUND

The effect of preoperative statin treatment (PST) on the risk of postoperative acute kidney injury (AKI) after cardiac surgery remains controversial. We performed a meta-analysis of randomised controlled trials (RCT) to investigate whether PST could improve the renal outcomes in patients undergoing cardiac surgery.

METHODS

We conducted a comprehensive search on PubMed, Embase and Cochrane Central Register of Controlled Trials. Randomised controlled trials which reported incidence of AKI and renal replacement treatment (RRT), mean change of serum creatine (SCr) and C-reactive protein (CRP), length of stay in intensive care unit (LOS-ICU) and hospital (LOS-HOS) were included.

RESULTS

A total of nine RCTs, covering 3,201 patients were included. Based on the results of our meta-analysis, PST could not reduce the incidence of AKI (risk ratio (RR) 1.12, 95% confidence interval (CI) 0.97 to 1.29, p=0.37), and RRT (RR 1.13, 95% CI 0.45 to 2.85, p=0.80). Furthermore, SCr was not likely to be improved by PST (weighted mean difference (WMD) 0.03, 95% CI 0.00 to 0.06, p=0.055). However, the level of CRP (WMD -5.93, 95% CI 11.71 to 0.15, p=0.044) in patients treated with PST was significantly lower than that of patients administered with placebo. In addition, no significant difference was observed in LOS-ICU and LOS-HOS between PST and control groups.

CONCLUSION

Our meta-analysis suggests that PST cannot provide any benefit for improving renal complications and clinical outcomes, but may slightly reduce postoperative inflammation in patients undergoing cardiac surgery. In the future, more powerful RCTs will be needed to confirm these findings.

Risk factors for hypernatremia in patients with short- and long-term tolvaptan treatment

PURPOSE

The long-term efficacy of tolvaptan, a vasopressin V2 receptor antagonist, has been reported. However, the safety of long-term treatment remains to be fully elucidated. We assessed the safety profile of tolvaptan with respect to hypernatremia.

METHODS

This retrospective study included 371 patients treated with tolvaptan. Risk factors for hypernatremia (serum sodium concentration ≥147 mEq/L) were determined.

RESULTS

Hypernatremia occurred in 95 patients (25.6 %), of whom 71 (19.1 %) developed hypernatremia within 7 days of tolvaptan treatment (early onset). Stepwise logistic regression analysis demonstrated that baseline serum sodium ≥140 mEq/L, an initial tolvaptan dosage >7.5 mg, and a BUN/serum creatinine ratio ≥20 were independent risk factors for early onset of hypernatremia. Tolvaptan was prescribed for more than 7 days to 233 patients, of whom 123 were administrated tolvaptan for more than 1 month. Hypernatremia occurred in 24 of these patients (10.3 %) (late onset). Predictive factors for late onset of hypernatremia were an average daily dosage of tolvaptan >7.5 mg and age ≥75 years.

CONCLUSIONS

A daily dosage of 7.5 mg or less was recommended to prevent hypernatremia in short- as well as long-term tolvaptan treatment, and mainly elderly patients were at risk for hypernatremia.