Evaluation of Costs Associated with Tolvaptan-Mediated Hospital Length of Stay Reduction Among US Patients with the Syndrome of Inappropriate Antidiuretic Hormone Secretion, Based on SALT-1 and SALT-2 Trials
ABSTRACT Two randomized clinical trials, the Study of Ascending Levels of Tolvaptan in Hyponatremia 1 and 2 (SALT-1 and SALT-2), showed that tolvaptan was an efficacious and safe therapy for the treatment of hyponatremic patients with the syndrome of inappropriate antidiuretic hormone secretion (SIADH).
This study evaluated the potential cost savings associated with tolvaptan usage based on the SALT-1 and SALT-2 trials.
Hospital length of stay (LOS) reduction associated with tolvaptan versus placebo was evaluated among hyponatremic patients with the SIADH (serum sodium < 135 mEq/L) from the combined data of the SALT-1 and SALT-2 trials. The Healthcare Cost and Utilization Project 2009 Nationwide Inpatient Sample database was used to estimate hospital cost and LOS for hospitalizations of adult (age ≥ 18 years) patients with the SIADH. A cost-offset model was constructed to evaluate the impact of tolvaptan on hospital cost and LOS, with univariate and multivariate Monte Carlo sensitivity analyses.
In the SALT-1 and SALT-2 trials, patients with the SIADH receiving tolvaptan had a shorter hospital LOS than patients receiving placebo (4.98 vs 6.19 days, respectively). There were 21 718 hospitalizations for the SIADH identified from the Healthcare Cost and Utilization Project Nationwide 2009 Inpatient Sample database, with a mean LOS of 5.7 days and mean total hospital costs of $8667. Using an inpatient tolvaptan treatment duration of 4 days, with a daily wholesale acquisition cost of $250, the cost-offset model estimated an LOS reduction among SIADH hospitalizations of 1.11 days. The total cost offset, including tolvaptan drug cost, was estimated to be $694 per admission. The cost-neutral break-even duration of tolvaptan therapy is 6.78 days. Univariate and multivariate sensitivity analyses demonstrated consistent cost reduction associated with tolvaptan usage. Ten thousand cycles of Monte Carlo simulation showed the 95% CI for cost offset to be $73 to $1405.
Based on the SALT-1 and SALT-2 trials, tolvaptan usage is associated with a shorter hospital LOS than placebo among patients with the SIADH. Including the drug cost for 4 days of inpatient tolvaptan therapy, tolvaptan is associated with an estimated mean hospital cost reduction of $694 per admission in the United States.
- SourceAvailable from: Bowen Jiang
[Show abstract] [Hide abstract]
- "Inclusion • Surgical resection of a pituitary mass between December 29, 2005 and September 15, 2012 • Pituitary adenoma with adrenocorticotropic hormone (ACTH) positive staining on pathology • Clinical signs and symptoms of Cushing's Syndrome (such as fatigue, weight gain, emotional lability, diabetes, proximal muscle weakness, easy bruisability, abdominal striae, and insomnia) • Postoperative serum sodium level of less than 130 mEq/L Exclusion • Treatment with desmopressin (DDAVP) for post-operative diabetes insipidus • Serum sodium levels of 131–135 mEq/L for less than 48 h (these patients did not receive treatment for hyponatremia) • Di-or pluri-hormonal tumors on pathological staining or any other endocrine abnormalities is a significant source of morbidity and mortality in this population . Furthermore, two recent studies provided the first evidence that in medical patients with SIADH, vaptans reduced inpatient length-of-stay and consequently medical costs associated with treatment of hyponatremia  . Our retrospective study was designed to compare rates of sodium stabilization and length of hospital stay in postoperative Cushing's patients managed with or without vaptan therapy. "
ABSTRACT: Hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a common osmoregulatory complication following surgery for Cushing's disease. Conventional management includes water restriction and sodium repletion, however this regimen does not address the underlying pathophysiology of excessive vasopressin production. Vaptans are arginine vasopressin receptor antagonists shown to be effective in correcting water excess in other disease states of euvolemic and hypervolemic hyponatremia. The use of these agents has not been reported in Cushing's patients. We retrospectively studied Cushing's patients at our institution with post-surgical hyponatremia (Na<130mEq/L) treated with and without conivaptan between 2005 and 2011. We report rates of serum sodium normalization and compare length-of-stay (LOS) between the groups. Hyponatremia developed in six of 98 patients (6.1%) undergoing resection of ACTH-positive pituitary adenomas. Three patients received conivaptan and fluid restriction±sodium supplementation, and three received conventional therapy alone. The rate of serum sodium normalization with conivaptan was 5.8±2.3mEq/L/20mg IV bolus given every 24h. All patients receiving conivaptan were discharged with normal serum sodium values and no instances of rapid overcorrection occurred. A trend toward longer LOS occurred in patients treated with conivaptan (4.6±0.3 days, mean±SE) versus conventional therapy alone (1.6±0.3 days). Conivaptan is a potentially useful treatment option for hyponatremia in the setting of Cushing's disease patients after pituitary surgery.Clinical neurology and neurosurgery 08/2013; 115(11). DOI:10.1016/j.clineuro.2013.08.019 · 1.25 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: The randomized clinical trials, RE-LY, ROCKET-AF, and ARISTOTLE, demonstrate that the novel oral anticoagulants (NOACs) are effective options for stroke prevention among non-valvular atrial fibrillation (AF) patients. This study aimed to evaluate the medical cost reductions associated with the use of individual NOACs instead of warfarin from the US payer perspective. Rates for efficacy and safety clinical events for warfarin were estimated as the weighted averages from the RE-LY, ROCKET-AF and ARISTOTLE trials, and event rates for NOACs were determined by applying trial hazard ratios or relative risk ratios to such weighted averages. Incremental medical costs to a US health payer of an AF patient experiencing a clinical event during 1 year following the event were obtained from published literature and inflation adjusted to 2010 cost levels. Medical costs, excluding drug costs, were evaluated and compared for each NOAC vs warfarin. Sensitivity analyses were conducted to determine the influence of variations in clinical event rates and incremental costs on the medical cost reduction. In a patient year, the medical cost reduction associated with NOAC usage instead of warfarin was estimated to be -$179, -$89, and -$485 for dabigatran, rivaroxaban, and apixaban, respectively. When clinical event rates and costs were allowed to vary simultaneously, through a Monte Carlo simulation, the 95% confidence interval of annual medical costs differences ranged between -$424 and +$71 for dabigatran, -$301 and +$135 for rivaroxaban, and -$741 and -$252 for apixaban, with a negative number indicating a cost reduction. Of the 10,000 Monte-Carlo iterations 92.6%, 79.8%, and 100.0% were associated with a medical cost reduction >$0 for dabigatran, rivaroxaban, and apixaban, respectively. Usage of the NOACs, dabigatran, rivaroxaban, and apixaban may be associated with lower medical (excluding drug costs) costs relative to warfarin, with apixaban having the most substantial medical cost reduction.Journal of Medical Economics 03/2012; 15(4):776-85. DOI:10.3111/13696998.2012.680555
- [Show abstract] [Hide abstract]
ABSTRACT: Tolvaptan is a member of a new class of drugs, called the vaptans, that antagonize receptors of the neurohormone arginine vasopressin. From a clinical perspective, tolvaptan has been shown to be efficacious in the treatment of hyponatremia, whether it is idiopathic or disease related, and it may have a more favorable benefit/risk profile than other treatment modalities. From an economic perspective, tolvaptan is an expensive drug for treating hyponatremia, but recent economic cost-offset models provide evidence that tolvaptan can be cost effective. The cost-effectiveness of tolvaptan is driven by reduced healthcare resource usage and hospitalization costs. More comparative research of tolvaptan versus other pharmacotherapies and analyses of patients treated with tolvaptan in the real world are needed to better determine the benefits of tolvaptan usage to patient outcome, and more accurately assess its value in the treatment of hyponatremia, an independent predictor of morbidity, mortality and cost.Expert Review of Pharmacoeconomics & Outcomes Research 08/2012; 12(4):399-410. DOI:10.1586/erp.12.30 · 1.87 Impact Factor