Comparison of utilization and cost of healthcare services and pharmacotherapy following implantation of vagus nerve stimulation vs. responsive neurostimulation or deep brain stimulation for the treatment of drug-resistant epilepsy: analyses of a large United States healthcare claims database

AIM

Vagus nerve stimulation (VNS), responsive neurostimulation (RNS), and deep brain stimulation (DBS) all are options for drug-resistant epilepsy (DRE). However, little is known about how the choice of neurostimulation impacts subsequent healthcare costs.

MATERIALS AND METHODS

We used a large US healthcare claims database to identify all patients with epilepsy who underwent neurostimulation between 2012 and 2019. Eligible patients were identified and stratified based on procedure received (VNS vs. RNS/DBS). VNS patients were matched by propensity scoring to RNS/DBS patients. Use and cost of healthcare resources and pharmacotherapy were ascertained over the 24-month period following neurostimulation, incorporating all-cause and epilepsy-related measures. Disease-related care was defined based on diagnoses of claims for medical care and relevant pharmacotherapies.

RESULTS

Seven hundred and ninety-two patients met all selection criteria. VNS patients were younger, were prescribed a higher pre-index mean number of anti-seizure medications (ASMs), and had higher pre-index levels of use and cost of epilepsy-related healthcare services. We propensity matched 148 VNS patients to an equal number of RNS/DBS patients. One year following index date (inclusive), mean total all-cause healthcare costs were 50% lower among VNS patients than RNS/DBS patients, and mean epilepsy-related costs were 55% lower; corresponding decreases at the two-year mark were 41% and 48%, respectively.

LIMITATIONS

Some clinical variables, such as seizure frequency and severity, quality of life, and functional status were unavailable in the database, precluding our ability to comprehensively assess differences between devices. Administrative claims data are subject to billing code errors, inaccuracies, and missing data, resulting in possible misclassification and/or unmeasured confounding.

CONCLUSIONS

After matching, VNS was associated with significantly lower all-cause and epilepsy-related costs for the two-year period following implantation. All-cause and epilepsy-related costs remained statistically significantly lower for VNS even after costs of implantation were excluded.

Analysis of pharmacotherapy regimen and costs in patients with drug-resistant epilepsy following vagus nerve stimulation therapy: a single-center study (Poland)

Approximately 30-40% of patients with drug-resistant epilepsy (DRE) who underwent vagus nerve stimulator (VNS) implantation achieve above 50% reduction in seizure frequency. VNS proves effective in reducing frequency of seizures in DRE patients, when combined with antiepileptic drugs (AEDs). This raises a question whether improvement of clinical parameters is achieved with VNS only or relies on combined therapy with AEDs. The aim of the study was the analysis of impact of VNS on clinical recovery of patients with DRE and the analysis of pharmacotherapy costs and drug regimen following VNS implantation in DRE patients. The study included all the patients who had VNS implanted at our department in the years 2014-2018. The patients would be followed up for 2 years after the VNS implantation date. The most commonly used drugs included levetiracetam, lacosamide, valproate, oxcarbazepine, and topiramate. Average cost of AEDs in year 1 following VNS implantation was between EUR 15.53 (CLB) and EUR 545.52 (TGB) and in year 2 between EUR 13.51 (NTZ) and EUR 779.44 (LAC). The greatest number of seizures affected the group of patients treated with three drugs. A statistically significant improvement in seizure frequency was observed in the group of patients treated with two and three drugs. With the rising costs of healthcare, the importance of economic efficiency is becoming increasingly relevant. VNS is a reasonable option for saving money in the healthcare system while ensuring measurable clinical and therapeutic outcomes over the long term.

Cost-effectiveness of noninvasive vagus nerve stimulation for acute treatment of episodic migraine and role in treatment sequence strategies

Migraine affects 15% of the population in the United States and is associated with comorbidities, with an estimated economic burden of $78 billion annually. GammaCore is used adjunctively with current standard of care and abortive medications and has shown to be superior in acute treatment of episodic migraine compared to sham. However, the economic impact has not been characterized for this indication. We conducted a cost-effectiveness analyses for 2 hypothetical scenarios: a primary model for treatment options gammaCore plus standard of care compared to standard of care alone for acute treatment of migraine; and a secondary model for treatment sequence strategies where acute treatment with gammaCore or standard of care each prior to erenumab prevention compared to initiating erenumab prevention with no prerequisite. The time horizon for the model is 1 year, using a payer perspective. GammaCore plus standard of care arm was dominant over standard of care alone in the primary model. The mean costs for gammaCore plus standard of care arm and standard of care individually were $9678 and $10,010, respectively. The mean quality of life-years for gammaCore plus standard of care arm and standard of care alone were 0.67, and 0.63, respectively. For the secondary model, the mean costs for gammaCore followed by erenumab, standard of care followed by erenumab and initiating with erenumab with no prior gammaCore or standard of care treatment were $10,678, $11,583, and $13,766. The corresponding mean for quality of life-years were 0.70, 0.67, and 0.65, respectively. For gammaCore dominance, ie, in this scenario, patients were more satisfied on gammaCore, to not need erenumab for preventative therapy lower mean costs and represents savings for payers. This was driven by efficacy, improvement in quality of life, and reduction in costs of care associated with successful treatment of migraine attacks. These findings provide new economic evidence to support value forcoverage for gammaCore.

Cost-effectiveness of gammaCore (non-invasive vagus nerve stimulation) for acute treatment of episodic cluster headache

Cluster headache is a debilitating disease characterized by excruciatingly painful attacks that affects 0.15% to 0.4% of the US population. Episodic cluster headache manifests as circadian and circannual seasonal bouts of attacks, each lasting 15 to 180 minutes, with periods of remission. In chronic cluster headache, the attacks occur throughout the year with no periods of remission. While existing treatments are effective for some patients, many patients continue to suffer. There are only 2 FDA-approved medications for episodic cluster headache in the United States, while others, such as high-flow oxygen, are used off-label. Episodic cluster headache is associated with comorbidities and affects work, productivity, and daily functioning. The economic burden of episodic cluster headache is considerable, costing more than twice that of nonheadache patients. gammaCore adjunct to standard of care (SoC) was found to have superior efficacy in treatment of acute episodic cluster headaches compared with sham-gammaCore used with SoC in ACT1 and ACT2 trials. However, the economic impact has not been characterized for this indication. We conducted a cost-effectiveness analysis of gammaCore adjunct to SoC compared with SoC alone for the treatment of acute pain associated with episodic cluster headache attacks. The model structure was based on treatment of acute attacks with 3 outcomes: failures, nonresponders, and responders. The time horizon of the model is 1 year using a payer perspective with uncertainty incorporated. Parameter inputs were derived from primary data from the randomized controlled trials for gammaCore. The mean annual costs associated with the gammaCore-plus-SoC arm was $9510, and mean costs for the SoC-alone arm was $10,040. The mean quality-adjusted life years for gammaCore-plus-SoC arm were 0.83, and for the SoC-alone arm, they were 0.74. The gammaCore-plus-SoC arm was dominant over SoC alone. All 1-way and multiway sensitivity analyses were cost-effective using a threshold of $20,000. gammaCore dominance, representing savings, was driven by superior efficacy, improvement in quality of life (QoL), and reduction in costs associated with successful and consistent abortion of episodic attacks. These findings serve as additional economic evidence to support coverage for gammaCore. Additional real-world data are needed to characterize the long-term impact of gammaCore on comorbidities, utilization, QoL, daily functioning, productivity, and social engagement of these patients, and for other indications.

Review of non-invasive vagus nerve stimulation (gammaCore): efficacy, safety, potential impact on comorbidities, and economic burden for episodic and chronic cluster headache

The FDA has cleared gammaCore (non-invasive vagus nerve stimulator [nVNS]) for the treatment of episodic cluster headache (eCH). With the exception of subcutaneous sumatriptan, all other treatments are used off label and have many limitations. The FDA approval process for devices differs from that of drugs. We performed a review of the literature to evaluate new evidence on various aspects of gammaCore treatment and impact. The ACute Treatment of Cluster Headache Studies (ACT1 and ACT2), both double-blind sham-controlled randomized trials, did not meet the primary endpoints of the trials but each demonstrated significant superiority of gammaCore among patients with eCH. In ACT1, gammaCore resulted in a higher response rate (RR) (RR, 3.2; 95% CI, 1.6-8.2; P = .014), higher pain-free rate for >50% of attacks (RR, 2.3; 95% CI, 1.1-5.2; P = .045), and shorter duration of attacks (mean difference [MD], -30 minutes; P <.01) compared with the sham group. In ACT2, gammaCore resulted in higher odds of achieving pain-free attacks in 15 minutes (OR, 9.8; 95% CI, 2.2-44.1; P = .01), lower pain intensity in 15 minutes (MD, -1.1; P <.01), and higher rate of achieving responder status at 15 minutes for ≥50% of treated attacks (RR, 2.8; 95% CI, 1.0-8.1; P = .058) compared with the sham group. The PREVention and Acute Treatment of Chronic Cluster Headache (PREVA) study also demonstrated that gammaCore plus standard of care (SOC) was superior to SOC alone in patients with chronic cluster headache (CH). Medical costs, pharmacy refills, and pharmacy costs were higher in patients coded for CH in claims data compared with controls with nonheadache codes. gammaCore is easy to use, practical, and safe; delivery cannot be wasted; and patients prefer using gammaCore compared with SOC. The treatment improves symptoms and reduces the need for CH rescue medications. Current US reimbursement policies, which predate nVNS and are based on expensive, surgically implanted, and permanent implanted vagus nerve stimulation (iVNS), need to be modified to distinguish nVNS from iVNS. gammaCore, cleared by the FDA in April 2017, provides substantial value to patients and also to payers. There is sufficient evidence to support the need to modify current reimbursement policies to include coverage for gammaCore (nVNS) for eCH.

Electrical stimulation for drug-resistant epilepsy: an evidence-based analysis

OBJECTIVE

The objective of this analysis was to evaluate the effectiveness of deep brain stimulation (DBS) and vagus nerve stimulation (VNS) for the treatment of drug-resistant epilepsy in adults and children.

DATA SOURCES

A literature search was performed using MEDLINE, EMBASE, the Cochrane Library, and the Centre for Reviews and Dissemination database, for studies published from January 2007 until December 2012.

REVIEW METHODS

Systematic reviews, meta-analyses, randomized controlled trials (RCTs), and observational studies (in the absence of RCTs) of adults or children were included. DBS studies were included if they specified that the anterior nucleus of thalamus was the area of the brain stimulated. Outcomes of interest were seizure frequency, health resource utilization, and safety. A cost analysis was also performed.

RESULTS

The search identified 6 studies that assessed changes in seizure frequency after electrical stimulation: 1 RCT on DBS in adults, 4 RCTs on VNS in adults, and 1 RCT on VNS in children. The studies of DBS and VNS in adults found significantly improved rates of seizure frequency, but the study of VNS in children did not find a significant difference in seizure frequency between the high and low stimulation groups. Significant reductions in hospitalizations and emergency department visits were found for adults and children who received VNS. No studies addressed the use of health resources for patients undergoing DBS. Five studies reported on adverse events, which ranged from serious to transient for both procedures in adults and were mostly transient in the 1 study of VNS in children.

LIMITATIONS

We found no evidence on DBS in children or on health care use related to DBS. The measurement of seizure frequency is self-reported and is therefore subject to bias and issues of compliance.

CONCLUSIONS

Based on evidence of low to moderate quality, both DBS and VNS seemed to reduce seizure frequency in adults. In children, VNS did not appear to be as effective at reducing seizure frequency, but children had significantly fewer hospitalizations and ED visits after VNS implantation. Despite the considerable risks associated with these invasive procedures, long-term adverse events appear to be limited.

PLAIN LANGUAGE SUMMARY

Electrical stimulation of specific areas of the brain is a procedure used to control epileptic seizures when more conventional treatments are not working. Most adults and children with epilepsy are able to control their seizures with medication, but for some patients, drugs are not effective and surgery to remove the part of the brain where the seizures start is not an appropriate option. This study looked at the research available on the effectiveness, safety, and cost of two types of electrical stimulation devices currently licensed for treatment of epilepsy for adults and children in Canada: vagus nerve stimulation (VNS) and deep brain stimulation (DBS). Both approaches appear to be effective at reducing the frequency of seizures in adults. However, the evidence on DBS is limited to a single study with adults; we found no studies of DBS with children. Studies on VNS showed that both adults and children had fewer hospitalizations and emergency department visits after the procedure. Both procedures carry serious risks, but several longer-term studies have found that adverse events appear to be limited. The cost of VNS, including the process of assessing whether or not patients are good candidates for the procedure, is estimated to be about $40,000 per person (and higher for DBS because the device is more expensive and the operating time is longer). Of the 70,000 people in Ontario with epilepsy, about 1,400 (300 children and 1,110 adults) may be candidates for VNS to reduce their seizures.

Medicare patient experience with vagus nerve stimulation for treatment-resistant depression

BACKGROUND

Major depressive disease (MDD) represents a cost burden to the US healthcare system: approximately one-third of MDD patients fail conventional treatment: multiple failures define treatment-resistant depression (TRD). Vagus nerve stimulation (VNS) therapy is an approved adjunctive treatment for TRD.

OBJECTIVE

To study the healthcare utilization experience of Medicare beneficiaries implanted with VNS (VNSBs) during Medicare coverage, compared with beneficiaries with TRD (TRDBs) and managed depression (Mdeps).

METHODS

A retrospective analysis of 100% standard analytic file (SAF) Medicare claims from 2006-2009 using specific criteria to identify a VNSB dataset, compared to TRDs and Mdeps datasets (extract of 5% sample SAF from 2001-2009) and 2009 general Medicare beneficiaries (GMBs). Comparative analysis included demographics, mortality, healthcare utilization, and costs.

RESULTS

Among patients meeting study criteria for VNSBs (n = 690), TRDBs (n = 4639), Mdeps (n = 7524), and GMBs (n > 36 million), VNSBs were on average: younger, more likely to be female, and white, with Medicare eligibility due to disability. Of the VNSBs in the 2-year post-implantation period: 5% died; 22% experienced no negative events (defined as hospitalizations for psychoses or poisoning, emergency room use, electroconvulsive therapy, or poisoning, suicidal ideation, or self-harm diagnoses); 29% experienced multiple negative events; and 41% had either a single hospitalization or only all-cause ER visits. VNSBs experiencing negative events had more complex co-occurring psychiatric diagnoses. The annual mortality rate for VNSBs post-implant was 19.9 deaths per 1000 patient years, compared with 46.2 (CI: 41.9-51.6) and 46.8 (CI: 43.4-50.4) deaths for TRDBs and Mdeps, respectively. The medical costs per patient-year post-VNS implantation for VNSBs ($8749) was similar to the Mdeps ($8960; CI $8555-$9381) and was substantially lower than TRDBs ($13,618; CI $12,937-$14,342).

CONCLUSIONS

VNSBs achieving positive health outcomes (measured by lack of negative events post-implantation) tend to have fewer psychiatric co-occurring conditions. Lowered costs post-implantation with evidence of response to VNS suggest the therapy represents an option for carefully screened TRDBs who have failed other therapies.

LIMITATIONS

Administrative data are missing pharmaceuticals and clinical measures. Data for the VNS population were not available pre-implantation for comparison to post-implantation experience. Cost comparisons are adjusted for missing costs in the VNS dataset.

Clinical and economic impact of vagus nerve stimulation therapy in patients with drug-resistant epilepsy

We evaluated long-term medical and economic benefits of vagus nerve stimulation (VNS) therapy in drug-resistant epilepsy. A pre-post analysis was conducted using multistate Medicaid data (January 1997-June 2009). One thousand six hundred fifty-five patients with one or more neurologist visits with epilepsy diagnoses (ICD-9 345.xx, 780.3, or 780.39), one or more procedures for vagus nerve stimulator implantation, one or more antiepileptic drugs (AEDs), and 6 or more months of continuous Medicaid enrollment pre- and post-VNS were selected. The pre-VNS period was 6 months. The post-VNS period extended from implantation to device removal, death, Medicaid disenrollment, or study end (up to 3 years). Incidence rate ratios (IRRs) and cost differences ($2009) were estimated. Mean age was 29.4 years. Hospitalizations decreased post-VNS compared with pre-VNS (adjusted IRR=0.59, P<0.001). Grand mal status events decreased post-VNS compared with pre-VNS (adjusted IRR=0.79, P<0.001). Average total health care costs were lower post-VNS than pre-VNS ($18,550 vs $19,945 quarterly, P<0.001). VNS is associated with decreased resource utilization and epilepsy-related clinical events and net cost savings after 1.5 years.

Vagus nerve stimulation for epilepsy

In the UK, around 0.5-1% of the population have epilepsy,1 and seizures remain uncontrolled in up to 50% of all people with the condition,2 which can have a significant impact on work, family and social life.2 Vagus nerve stimulation is now being used in both adults and children for epilepsy that is refractory to medical treatment.3-7 Worldwide, over 52,000 patients have been treated with such a device. Here we examine the place of vagus nerve stimulation therapy in the management of people with epilepsy.

Longer-term effects of implanted vagal nerve stimulation

Vagal nerve stimulation (VNS) is a non-pharmacologic therapeutic intervention approved in adults and children with neuropsychiatric disorders. Studies conducted over the past 20 years have demonstrated that VNS results in immediate and longer-term changes in brain regions implicated in neuropsychiatric disorders, such as the thalamus, cerebellum, orbitofrontal cortex, limbic system, hypothalamus, and medulla with vagus innervations. This review summarizes the effects of longer-term implanted VNS and how the incorporation of this non-pharmacologic therapeutic management in the treatment regime can be beneficial to address the needs of patients who are unable to tolerate medications and/or undergo surgery and do not respond to pharmacologic therapies. We also highlight the therapeutic efficacy of longer-term implanted VNS, safety, tolerability, patient acceptance, adherence, and adverse events, if any, in adults and children in this modality of treatment.