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

Effect of early administration of tolvaptan on pleural effusion post-hepatectomy

PURPOSE

This study evaluated the efficacy of tolvaptan administration at the early stage after hepatectomy to control pleural effusion and improve the postoperative course.

METHODS

Patients were administered tolvaptan (7.5 mg) and spironolactone (25 mg) from postoperative day 1 to postoperative day 5 (tolvaptan group, n = 68) for 13 months. Early administration of tolvaptan was not provided in the control group (n = 68); however, diuretics were appropriately administered according to the patient's condition. The amount of pleural effusion on computed tomography on postoperative day 5 was compared between the two groups.

RESULTS

The amount of pleural effusion and increase in body weight on postoperative day 5 showed significant differences in both groups (p < 0.001 and p = 0.019, respectively). However, the rate of pleural aspiration and the duration of postoperative hospitalization were comparable between the groups. The amount of intraoperative blood loss and lack of early administration of tolvaptan were identified as independent risk factors contributing to pleural effusion on multivariate analysis.

CONCLUSION

Early administration of tolvaptan to patients after hepatectomy was found to be capable of controlling postoperative pleural effusion and increase in body weight, but it did not reduce the rate of pleural aspiration or the hospitalization period.

Urea Transporter Inhibitor 25a Reduces Ascites in Cirrhotic Rats

Ascites is a typical symptom of liver cirrhosis that is caused by a variety of liver diseases. Ascites severely affects the life quality of patients and needs long-term treatment. 25a is a specific urea transporter inhibitor with a diuretic effect that does not disturb the electrolyte balance. In this study, we aimed to determine the therapeutic effect of 25a on ascites with a dimethylnitrosamine (DMN)-induced cirrhotic rat model. It was found that 100 mg/kg of 25a significantly increased the daily urine output by 60% to 97% and reduced the daily abdominal circumference change by 220% to 260% in cirrhotic rats with a water intake limitation. The 25a treatment kept the serum electrolyte levels within normal ranges in cirrhotic rats. The H&E and Masson staining of liver tissue showed that 25a did not change the cirrhotic degree. A serum biochemical examination showed that 25a did not improve the liver function in cirrhotic rats. A Western blot analysis showed that 25a did not change the expression of fibrosis-related marker protein α-SMA, but significantly decreased the expressions of type I collagen in the liver of cirrhotic rats, indicating that 25a did not reverse cirrhosis, but could slow the cirrhotic progression. These data indicated that 25a significantly reduced ascites via diuresis without an electrolyte imbalance in cirrhotic rats. Our study provides a proof of concept that urea transporter inhibitors might be developed as novel diuretics to treat cirrhotic ascites.

A cross-sectional survey of hospitalization and blood tests implementation status in patients who received tolvaptan under 75 years of age using a Japanese claims database

BACKGROUND

Hypernatremia and liver injury are typical adverse effects of tolvaptan. Therefore, hospitalization and frequent monitoring of serum sodium concentration and liver function are necessary for tolvaptan initiation. We performed a cross-sectional survey to evaluate these situations.

RESEARCH DESIGN AND METHODS

We employed the Japanese claims database, which contains data of patients aged < 75 years. Patients who were newly prescribed tolvaptan for fluid accumulation induced by chronic heart failure (FA-CHF) or liver cirrhosis (FA-LC) from January 2011 to June 2017 were included. We evaluated the hospitalization status and implementation of serum sodium and liver function tests in the evaluation period, based on the Japanese package insert.

RESULTS

Of 1,173 patients, 347 and 117 were enrolled in FA-CHF and FA-LC groups, respectively. Among them, 10.7% (FA-CHF group) and 5.13% (FA-LC group) were prescribed tolvaptan without hospitalization. In the FA-CHF group, 11.0% and 17.6% did not undergo serum sodium and liver function tests even once in the evaluation period, respectively, compared with 12.0% and 12.8% in the FA-LC group.

CONCLUSIONS

Our results highlight the deviation from Japanese package insert recommendations. This approach can be applied to other drugs and provides important perspectives on pharmacovigilance research.

Tolvaptan-induced hypernatremia related to low serum potassium level accompanying high blood pressure in patients with acute decompensated heart failure

Backgrounds

Tolvaptan significantly increases urine volume in acute decompensated heart failure (ADHF); serum sodium level increases due to aquaresis in almost all cases. We aimed to elucidate clinical factors associated with hypernatremia in ADHF patients treated with tolvaptan.

Methods

We enrolled 117 ADHF patients treated with tolvaptan in addition to standard therapy. We examined differences in clinical factors at baseline between patients with and without hypernatremia in the initial three days of hospitalization.

Results

Systolic (p = 0.045) and diastolic (p = 0.004) blood pressure, serum sodium level (p = 0.002), and negative water balance (p = 0.036) were significantly higher and serum potassium level (p = 0.026) was significantly lower on admission day in patients with hypernatremia (n = 22). In multivariate regression analysis, hypernatremia was associated with low serum potassium level (p = 0.034). Among patients with serum potassium level ≤ 3.8 mEq/L, the cutoff value obtained using receiver operating characteristic curve analysis, those with hypernatremia related to tolvaptan treatment showed significantly higher diastolic blood pressure on admission day (p = 0.004).

Conclusion

In tolvaptan treatment combined with standard therapy in ADHF patients, serum potassium level ≤ 3.8 mEq/L may be a determinant factor for hypernatremia development. Among hypokalemic patients, those with higher diastolic blood pressure on admission may be carefully managed to prevent hypernatremia.

Hypertonic saline, isotonic saline, water restriction, long loops diuretics, urea or vaptans to treat hyponatremia

Introduction: Hyponatremia is the most common fluid and electrolyte abnormality. It is associated with much higher morbidity and mortality rates than found in non hyponatremic patients.Areas covered: When the physician is faced to a hyponatremic patient he first has to confirm that hyponatremia is associated with hypoosmolality. Then he must answer to a series of questions: What is its origin? Is it acute or chronic? Which treatment is the most appropriate? We will discuss the various options for the treatment of hypotonic hyponatremia. For a better comprehensive approach of the treatment we will also discuss some pathophysiological data. The use of urea in euvolemic and hypervolemic hyponatremia will be particularly discussed. Literature was reviewed from Jan 1970 to Dec 2019.Expert opinion: Prospective studies showing the benefit in decreasing morbidity by increasing SNa in patients with chronic hyponatremia should be done. These studies should also compare the efficacy and side effects of urea therapy compare to vaptans.

Post-hepatectomy tolvaptan-induced hypernatremia in a hepatocellular carcinoma patient with cirrhosis: a case report

Background

Tolvaptan is used in Japan to reduce fluid retention caused by cirrhosis. However, hypernatremia is one of the most important side effects. This report is the first case report of a patient who developed hypernatremia after tolvaptan administration in the early stages following hepatectomy.

Case presentation

A female patient in her 60s, who was admitted to the psychiatric department of a different hospital for bipolar disorder, developed hepatocellular carcinoma with cirrhosis. She was transferred to our hospital, and hepatectomy was performed in October 2019, after which pleural effusion and severe edema due to fluid retention were evident. Thus, the patient was started on tolvaptan (7.5 mg/day) from postoperative day (POD) 1. The patient began to experience disturbance of consciousness after POD 4. On the fifth day, the serum sodium (Na) level increased to 174 mEq/L, and hypernatremia was diagnosed. The Na level gradually improved with fluid infusion therapy, dropping to preoperative levels on the ninth day; her consciousness also gradually improved.

Conclusions

Tolvaptan administration must be performed under strictly controlled conditions, followed by careful observation during the early postoperative period, when the patient’s physical status is unstable.

[Development of Stratified and Personalized Medicine Based on Pharmacogenomic and Pharmacokinetic Analyses]

To administer optimal and safe pharmacotherapy, development of stratified and personalized therapy is imperative. Pharmacogenomics (PGx) is useful in elucidating factors causing individual differences in drug efficacy and the emergence of adverse effects. It also helps design accurate drug administration methods by evaluating the effects of patient-related factors, such as genetic factors, that influence pharmacokinetics (PK) and pharmacodynamics (PD). In addition, selection of appropriate therapeutic agents requires the implementation of precision medicine allowing accurate disease diagnosis. To establish precision medicine, it is necessary to uncover the association of pathophysiological factors, which are represented as endotype or genotype, with the pathology of several phenotypes. This review describes two aspects related to realization of individualized medicine, namely the effectiveness of PK/PD/PGx studies and the stratification of pathological conditions. First, we conducted a PK/PD/PGx study with the aim to individualize warfarin treatment. In this study, we elucidated the effect of CYP4F2 polymorphisms associated with vitamin K metabolism by measuring the blood concentrations of warfarin and vitamin K. Then, to develop precision medicine for asthma and chronic obstructive pulmonary disease (COPD), we analyzed not only clinical symptoms but also pathological biomarkers and genes associated with inflammation. The findings may contribute toward better understanding of the pathological conditions of asthma, COPD, and asthma-COPD overlap.

A selective oral vasopressin V2-receptor antagonist for patients with end-stage liver disease awaiting liver transplantation: a preliminary study

Administration of the selective arginine vasopressin V2 receptor antagonist tolvaptan to cirrhotic patients is controversial. There are no reports of tolvaptan use for patients with far-advanced end-stage liver disease (ESLD) and refractory ascites awaiting liver transplantation. Between 2013 and 2016, 64 patients awaiting adult-to-adult living donor liver transplantation (LDLT) were screened for enrollment. Patients with refractory ascites and on dual conventional diuretics (≥ 50 mg/day of spironolactone and ≥ 20 mg/day of a loop diuretic) were enrolled and assigned to the tolvaptan (TOL) group (n = 10), and low-dose tolvaptan, 3.75 mg/day, was started. The remaining patients who had no or little ascites on conventional diuretic therapy (CDT) were assigned to the CDT group (n = 23). The median model for end-stage liver disease and Child-Pugh scores were 16 (range 7-41) and 10 (7-15), respectively. The median dose of spironolactone in the TOL group was 88 mg (range 50-200) vs. 50 (0-100) in the CDT group (p < 0.01). The median dose of loop diuretics in the TOL group was 70 mg (20-120) vs. 20 (0-80) in the CDT group (p = 0.03). No significant liver damage was detected during tolvaptan therapy. Tolvaptan demonstrated favorable effects in 60% (6/10) of the patients, decreasing the body weight by at least 1.5 kg during the 7 day treatment. These findings suggest that low-dose of tolvaptan may be safe for patients having far-advanced ESLD patients with apparent and refractory ascites taking dual conventional diuretics for a short period before LDLT.

The Role of Tolvaptan Administration After Cardiac Surgery: A Meta-Analysis

OBJECTIVE

To evaluate the efficacy and safety of tolvaptan in fluid management after cardiac surgery compared with conventional diuretic treatment.

DESIGN

Systematic review of the literature with meta-analyses.

SETTING

The Medline, Scopus, Cochrane Central Register of Controlled Trials, Clinicaltrials.gov, and Google Scholar databases were searched from inception to July 30, 2018.

PARTICIPANTS

The study comprised 759 patients undergoing cardiac surgery.

INTERVENTIONS

Tolvaptan administration (n = 397) or standard diuretic therapy (n = 398).

MEASUREMENTS AND MAIN RESULTS

Ten studies were included in the present meta-analysis. Tolvaptan administration was associated with a significantly faster return to preoperative body weight (mean difference [MD)] -1.48 d, 95% confidence interval [CI] -1.92 to 1.03), shorter duration of hospital stay (MD -2.58 d, 95% CI -5.09 to -0.07), lower incidence of acute kidney injury (odds ratio 0.34, 95% CI 0.16-0.69), and greater urine output (MD 0.47 L/d, 95% CI 0.25-0.69) and sodium levels (MD 2.85 mEq/L, 95% CI 1.90-3.80). No significant differences were present regarding duration of intensive care unit stay (MD -0.09 d, 95% CI -0.33 to 0.15), arrhythmia incidence (odds ratio 0.58, 95% CI 0.33-1.02), and serum creatinine values (MD -0.08 mg/dL, 95% CI -0.20 to 0.04).

CONCLUSIONS

The outcomes of the present meta-analysis suggest the promising role of tolvaptan administration in the management of fluid retention in patients after cardiac surgery. Future large-scale clinical trials should be conducted to fully elucidate its efficacy and to assess the optimal treatment protocol to be applied in the clinical setting.

Rapidity of Correction of Hyponatremia Due to Syndrome of Inappropriate Secretion of Antidiuretic Hormone Following Tolvaptan

BACKGROUND

Tolvaptan effectively corrects hyponatremia due to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), but undesired overcorrection can occur. We hypothesized that pretherapy parameters can predict the rapidity of response to tolvaptan in SIADH.

STUDY DESIGN

Multicenter historical cohort study.

SETTING & PARTICIPANTS

Adults with SIADH or congestive heart failure (CHF) treated with tolvaptan for a serum sodium concentration ≤ 130 mEq/L at 5 US hospitals.

PREDICTORS

Demographic and laboratory parameters.

OUTCOMES

Rate of change in serum sodium concentration.

MEASUREMENTS

Spearman correlations, analysis of variance, and multivariable linear mixed-effects models.

RESULTS

28 patients with SIADH and 39 patients with CHF treated with tolvaptan (mean baseline serum sodium, 120.6 and 122.4 mEq/L, respectively) were studied. Correction of serum sodium concentration > 12 mEq/L/d occurred in 25% of patients with SIADH compared to 3% of those with CHF (P<0.001). Among patients with SIADH, the increase in serum sodium over 24 hours was correlated with baseline serum sodium concentration (r=-0.78; P<0.001), serum urea nitrogen concentration (SUN; r=-0.76; P<0.001), and estimated glomerular filtration rate (r=0.58; P=0.01). Baseline serum sodium and SUN concentrations were identified as independent predictors of change in serum sodium concentration in multivariable analyses. When patients were grouped into 4 categories according to baseline serum sodium and SUN median values, those with both low baseline serum sodium (≤121 mEq/L) and low baseline SUN concentrations (≤10mg/dL) exhibited a significantly greater rate of increase in serum sodium concentration (mean 24-hour increase of 15.4 mEq/L) than the other 3 categories (P<0.05). Among patients with CHF, only baseline SUN concentration was identified as an independent predictor of change in serum sodium concentration over time.

LIMITATIONS

Lack of uniformity in serial serum sodium concentration determinations and documentation of water intake.

CONCLUSIONS

Baseline serum sodium and SUN values are predictive of the rapidity of hyponatremia correction following tolvaptan use in SIADH. We advise caution when dosing tolvaptan in patients with both low serum sodium and SUN concentrations.

The Outcome of Cirrhotic Patients with Ascites Is Improved by the Normalization of the Serum Sodium Level by Tolvaptan

Objective Hyponatremia is frequently observed in patients with decompensated liver cirrhosis and it is also related to a poor prognosis. The vasopressin V2-receptor antagonist tolvaptan is used to treat cirrhotic patients with ascites and increases the serum sodium (Na) level. In this study, we investigated (i) whether or not correction of the Na level improves the prognosis of cirrhotic patients with ascites and (ii) predictors of normalization of the serum Na level after tolvaptan therapy. Methods This was a single-center retrospective study. A total of 95 Japanese cirrhotic patients (60 men, median age 63 years) were enrolled and received tolvaptan orally after hospitalization for ascites treatment. The serum Na level was monitored during the period of tolvaptan treatment. The laboratory data and survival rates of patients who achieved serum Na levels of <135 and ≥135 mEq/L after 1 week were compared. Results Patients showed serum Na levels of 136 (121-145) mEq/L, and 42.1% had a serum Na level of <135 mEq/L. Among patients with an initial serum Na level <135 mEq/L, 60.0% achieved a normal level after 1 week, and the survival rate was significantly higher in patients with a normalized serum Na level (p<0.01). The pretreatment brain natriuretic peptide (BNP) level was predictive of achieving a serum Na level of ≥135 mEq/L (odds ratio: 0.87, 95% confidence interval: 0.316-0.987, p<0.05). Conclusion Normalization of the Na level after one week was associated with a favorable outcome of tolvaptan therapy, and Na correction improved the prognosis.

Good response to tolvaptan shortens hospitalization in patients with congestive heart failure

Tolvaptan has been gradually spread to use as a potent diuretic for congestive heart failure in the limited country. However, the response to this aquaretic drug still is unpredictable. A total of 92 patients urgently hospitalized due to congestive heart failure and treated with tolvaptan in addition to standard treatment was retrospectively analyzed. Responder of tolvaptan treatment was defined as a patient with peak negative fluid balance greater than 500 mL/day, and clinical profiles were compared between 76 responders and 16 non-responders. Responders started to increase daily urine volume (UV) from Day 1 through Day 3. In contrast, non-responders showed no significant increase in daily UV from the baseline up to Day 5. Time between admission and tolvaptan administration was shorter in responders, even without statistical significance (3.3 vs. 4.6 days, p = 0.053). Multivariate analysis revealed that blood urea nitrogen (BUN) [cutoff: 34 mg/dL, odds ratio (OR) 9.0, 95% confidence interval (CI) 1.42-57.3, p < 0.01] and plasma renin activity (PRA) (cutoff: 4.7 ng/mL/h, OR 6.1, 95% CI 1.01-36.4, p < 0.01) at baseline were independent predictors for tolvaptan responsiveness. It suggests that renal perfusion may affect tolvaptan-induced UV. Finally, durations of stay in intensive care unit and total hospitalization were significantly shorter in responders (median: 6.0 vs. 13.0 days, p = 0.022; 15.0 vs. 25.0 days, p = 0.016, respectively). Responders of tolvaptan have lower BUN and renin activity at baseline, and shorten hospitalization period. Trial Registration The study was registered at University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) with the identifier UMIN000023594. https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000024988.

Efficacy of tolvaptan for the patients with advanced hepatocellular carcinoma

AIM

To investigate the factors influenced the efficacy of tolvaptan (TLV) in liver cirrhosis.

METHODS

We retrospectively enrolled 61 consecutive patients with refractory hepatic ascites. All of them had been treated with furosemide and spironolactone before admission, and treated with TLV for 7 d in our hospital. The effect of TLV was defined by the rate of body weight loss, and the factors that influenced TLV efficacy were analyzed using multiple regression.

RESULTS

Coexistent hepatocellular carcinoma (HCC) was the only significant predictive variable that attenuated the efficacy of TLV. In stratified analysis, high doses of furosemide decreased the efficacy of TLV in patients with HCC, and increased efficacy in those without HCC. In the latter, a high Child-Pugh-Turcotte score had a positive influence and a high concentration of lactate dehydrogenase had a negative influence on the effectiveness of TLV.

CONCLUSION

Development of ascites may differ between patients with liver failure and those with HCC progression. A sufficient preceding dose of furosemide decreases diuretic effect of TLV.

Vasopressin Receptor Antagonists for the Correction of Hyponatremia in Chronic Heart Failure: An Underutilized Therapeutic Option in Current Clinical Practice?

In the congestive heart failure (CHF) setting, chronic hyponatremia is very common. The present review aims at addressing topics relevant to the pathophysiology of hyponatremia in the course of CHF as well as its optimal treatment, including the main advantages and the limitations resulting from the use of the available dietary and pharmacological measures approved for the treatment of this electrolytic trouble. A narrative review is carried out in order to represent the main modalities of therapy for chronic hyponatremia that frequently complicates CHF. The limits of usual therapies implemented for CHF-related chronic hyponatremia are outlined, while an original analysis of the main advancements achieved with the use of vasopressin receptor antagonists (VRAs) is also executed. The European regulatory restrictions that currently limit the use of VRAs in the management of CHF are substantially caused by financial concerns, i.e., the high costs of VRA therapy. A thoughtful reworking of current restrictions would be warranted in order to enable VRAs to be usefully associated to loop diuretics for decongestive treatment of CHF patients with hyponatremia.