Antiviral therapies for herpes zoster infections. Are they economically justifiable?

Teaching Medical Decision Modeling: A Qualitative Description of Student Errors and Curriculum Responses

Background. Novice medical decision modelers are prone to errors. The purpose of this article is to describe the common errors committed by decision modeling students and the changes made to a structured decision modeling project course in response. Curriculum. The decision modeling curriculum includes month-long segments in decision analysis, cost-effectiveness analyses, and a project course. In the project course, students solve a decision problem with prespecified assumptions and input variable values, with the expectation that all reach the same answer. At first, students worked in groups of 2 or 3 but more recently work individually; over time, there have been other changes in the course. Originally, the only assignment was an abstract and 10-minute presentation describing their solution, but now periodic homework monitors progress. Outcomes. Students' results frequently differed significantly from the expected answers. Errors were common in sensitivity analyses and model construction, among other areas. Defensible differences in structural programming decisions were rare. More recently, result ranges have narrowed as stepwise homework ensures progress and areas prone to error are emphasized. Student communication is timelier, facilitated by homeworkrelated questions. Individual, rather than group, work avoids potential problems with weaker students being carried by the more advanced. Student satisfaction has increased, with more beginning their own projects afterward. Conclusion. Solving a common decision problem is an efficient teaching tool. Closer supervision leads to increased satisfaction and decreased frustration, facilitated by a more structured approach and the anticipation of common errors.

Prevention of shingles by varicella zoster virus vaccination

Herpes zoster is caused by reactivation from previous varicella zoster virus (VZV) infection, and affects millions of people worldwide. It primarily affects older adults and those with immune system dysfunction, most likely as a result of reduced or lost VZV-specific cell-mediated immunity. Complications include post-herpetic neuralgia, a potentially debilitating and chronic pain syndrome. Current treatment of herpes zoster and post-herpetic neuralgia involves antiviral agents and analgesics, and is associated with significant economic cost. Results from several clinical trials have determined that a live, attenuated VZV vaccine using the Oka/Merck strain (Zostavax) is safe, elevates VZV-specific cell-mediated immunity, and significantly reduces the incidence of herpes zoster and post-herpetic neuralgia in people over 60 years of age. Regulatory approval has recently been obtained and once launched, it is expected that this vaccine will significantly reduce the morbidity and financial costs associated with herpes zoster. Durability of vaccine response and possible booster vaccination will still need to be determined.

Effect of pregabalin in the treatment of refractory neck pain: cost and clinical evidence from medical practice in orthopedic surgery and rehabilitation clinics

BACKGROUND

The study aims to prospectively analyze the effect of adding pregabalin upon costs and consequences in the treatment of refractory neck pain under routine medical practice.

METHODS

A secondary analysis was carried out including patients over 18 years, with 6-month chronic neck pain refractory from a prospective, naturalistic, 12-week two-visit study. The analysis compared patients adding pregabalin to its therapy vs. usual care. Severity of pain, healthcare resources utilization, lost workday equivalents (LWDE) because of pain, and related cost-adjusted reductions were assessed.

RESULTS

A total of 312 patients (65.3% women, age 54.2 [12.1] years), 78.2% receiving pregabalin, were analyzed. Adding pregabalin was associated with higher adjusted reduction in pain severity: -3.2 (1.8) points, 55.4% responders (≥50% baseline pain reduction) vs. -2.3 (2.0) and 38.2%, respectively; P<0.001, yielding a higher reduction in mean LWDE: 20.1 (23.1) vs. 8.2 (22.4); P=0.014, which produced significant reductions in the indirect components of cost: €1,041.0 (1,222.8) vs. €457.3 (1,132.1), P=0.028. The costs of pregabalin (€309.8 [193.2] vs. €26.4 [79.6], P<0.001) was offset by higher numerical reductions in the other components of costs, producing similar direct cost reductions in both groups at the end of the study: €66.8 (1,080.8) and €143.5 (1,922.4), respectively; P=0.295.

CONCLUSION

Compared with usual care, the addition of pregabalin to treat refractory neck pain seems to be associated with a higher reduction in pain severity and lost work-days equivalents, which in turn results in a greater reduction of the indirect components of cost while maintaining similar healthcare cost levels despite its higher price.

A cost-consequence analysis of pregabalin versus usual care in the symptomatic treatment of refractory low back pain: sub-analysis of observational trial data from orthopaedic surgery and rehabilitation clinics

BACKGROUND

low back pain is one of the most common reasons for outpatient consultation in both the primary-care and specialized-care settings. However, few studies have explored the effect of pregabalin in this context.

OBJECTIVE

to prospectively analyse the effect of adding pregabalin on costs and consequences in the treatment of refractory low back pain in routine medical practice.

METHODS

a secondary analysis was carried out in patients aged >or=18 years with a 6-month history of chronic refractory low back pain who had participated in a previous prospective, naturalistic, 12-week, two-visit study (RADIO study). The analysis compared patients receiving pregabalin with those receiving usual care. Severity of pain, healthcare resources utilization, lost workday equivalents due to pain, and related cost-adjusted reductions were assessed. The year of costing for all cost data reported in the study was 2007.

RESULTS

data from a total of 683 patients (49.5% women, mean age 55.0 years), 82.6% of whom were receiving pregabalin, were analysed. Pregabalin was associated with a higher covariable-adjusted reduction in severity of pain, i.e. mean (SD) -3.4 (2.0) compared with -2.0 (2.1) points with usual care on a 10-point neuropathic pain questionnaire (p < 0.001), and a 61.6% response rate (defined as >/=50% reduction in pain from baseline) compared with 37.3% with usual care (p < 0.001). This resulted in fewer lost workday equivalents in the pregabalin group versus usual care (27.8 vs 34.6, p = 0.002), which produced more significant adjusted reductions in indirect costs, i.e. mean (SD) -euro961.8 (euro1242.9) compared with -euro625.8 (euro1169.2) with usual care (p = 0.004). The cost of pregabalin, i.e. mean (SD) euro303.8 (euro175.8) compared with euro37.1 (euro97.0) for usual care (p < 0.001), was offset by larger reductions in the other cost components. While the adjusted total costs were substantially reduced in both groups, pregabalin-treated patients showed more significant reductions, i.e. mean (SD) -euro991.5 (euro1702.3) compared with -euro579.3 (euro2410.3) with usual care (p = 0.023).

CONCLUSION

compared with usual care, addition of pregabalin to existing therapy for refractory low back pain was associated with a larger reduction in pain severity and lost workday equivalents. The acquisition cost of pregabalin was offset by a higher reduction in the indirect components of cost, resulting in a significant decrease in total costs.

Cost-effectiveness of eszopiclone for the treatment of adults with primary chronic insomnia

STUDY OBJECTIVE

To assess the cost-effectiveness of treatment with eszopiclone for chronic primary insomnia in adults.

METHODS

A model using patient-level data from a 6-month, double-blind, placebo-controlled, clinical trial (n = 824), combined with data from a claims database and published literature, was used to assess the quality-adjusted life years (QALYs) gained and costs associated with eszopiclone versus placebo in adults with primary insomnia. Quality of life data were collected during the trial via the SF-36, from which preference-based utility scores were derived using published algorithms. Medical and absenteeism costs, estimated via a retrospective analysis of a claims and absenteeism database, were assigned to patients based on the degree of severity of their insomnia, assessed via the Insomnia Severity Index collected in the clinical trial. Presenteeism costs (lost productivity while at work) were estimated from responses to the Work Limitation Questionnaire collected during the trial. Six-month gains in QALYs and costs for each treatment group were calculated to derive cost-effectiveness ratios. Uncertainty was addressed via univariate and multivariate sensitivity analyses.

RESULTS

Over the 6-month period, eszopiclone use resulted in a net gain of 0.0137 QALYs over placebo at an additional cost of $67, resulting in an incremental cost per QALY gained of slightly less than $5,000. When absenteeism and presenteeism costs were excluded, the cost-effectiveness ratio increased to approximately $33,000 per QALY gained, which is below the commonly used threshold of $50,000 used to define cost-effectiveness. Extensive sensitivity analyses indicate the results are generally robust.

CONCLUSION

Our model, based on efficacy data from a clinical trial, demonstrated eszopiclone was cost-effective for the treatment of primary insomnia in adults, especially when lost productivity costs were included.

Neuropathic pain: quality-of-life impact, costs and cost effectiveness of therapy

A number of different diseases or injuries can damage the central or peripheral nervous system and produce neuropathic pain (NP), which seems to be more difficult to treat than many other types of chronic pain. As a group, patients with NP have greater medical co-morbidity burden than age- and sex-adjusted controls, which makes determining the humanistic and economic burden attributable to NP challenging. Health-related quality of life (HR-QOL) is substantially impaired among patients with NP. Patients describe pain-related interference in multiple HR-QOL and functional domains, as well as reduced ability to work and reduced mobility due to their pain. In addition, the spouses of NP patients have been shown to experience adverse social consequences related to NP. In randomized controlled trials, several medications have been shown to improve various measures of HR-QOL. Changes in HR-QOL appear to be tightly linked to pain relief, but not to the development of adverse effects. However, in cross-sectional studies, many patients continue to have moderate or severe pain and markedly impaired HR-QOL, despite taking medications prescribed for NP. The quality of NP treatment appears to be poor, with few patients receiving recommended medications in efficacious dosages. The substantial costs to society of NP derive from direct medical costs, loss of the ability to work, loss of caregivers' ability to work and possibly greater need for institutionalization or other living assistance. No single study has measured all of these costs to society for chronic NP. The cost effectiveness of various interventions for the treatment or prevention of different types of NP has been assessed in several different studies. The most-studied diseases are post-herpetic neuralgia and painful diabetic neuropathy, for which tricyclic antidepressants (both amitriptyline and desipramine) have been found to be either cost effective or dominant relative to other strategies. Increasing the use of cost-effective therapies such as tricyclic antidepressants for post-herpetic neuralgia and painful diabetic neuropathy may improve the HR-QOL of patients and decrease societal costs. Head-to-head clinical trials comparing NP therapies are needed to help assess the relative clinical efficacy of treatments, ideally using HR-QOL and utility outcomes. The full costs to society of NP, including productivity loss costs, have not been determined for chronic NP. Improved relative efficacy, utility and cost estimates would facilitate future cost-effectiveness research in NP.

Cost effectiveness of long-term treatment with eszopiclone for primary insomnia in adults: a decision analytical model

OBJECTIVE

Although the clinical benefits of pharmacological treatments for insomnia have been studied, no systematic assessment of their economic value has been reported. This analysis assessed, from a broad payer and societal perspective, the cost effectiveness of long-term treatment with eszopiclone (LUNESTA, Sepracor Inc., [Marlborough, MA, USA]) for chronic primary insomnia in adults in the US.

METHODS

A decision analytical model was developed based on the reanalysis of a 6-month placebo-controlled trial, which demonstrated that eszopiclone 3mg significantly improved sleep and daytime function measures versus placebo in adults with primary insomnia. Patients were classified as either having remitted or not remitted from insomnia based upon a composite index of eight sleep and daytime function measures collected during the trial. These data were supplemented with quality-of-life and healthcare and lost productivity cost data from the published literature and medical and absenteeism claims databases.

RESULTS

Compared with non-remitted patients, patients classified as remitted had lower monthly healthcare and productivity costs (in 2006 dollars) [a reduction of $US242 and $US182, respectively] and higher quality-adjusted life-year (QALY) weight (a net gain of 0.0810 on a scale ranging from 0 to 1). During the study, eszopiclone-treated patients were about 2.5 times more likely to have remitted than placebo-treated patients. Six months of eszopiclone treatment reduced direct (healthcare) and indirect (productivity) costs by an estimated $US245.13 and $US184.19 per patient, respectively. Eszopiclone use was associated with a cost of $US497.15 per patient over 6 months (including drug cost, dispensing fee, physician visit and time loss to receive care). Thus, after considering the above savings and the costs associated with eszopiclone treatment over 6 months, cost increased by $US252.02 (excluding productivity gains) and $US67.83 (including productivity gains) per person. However, eszopiclone treatment was also associated with a net QALY gain of 0.006831 per patient over the same period. Consequently, the incremental cost per QALY gained associated with eszopiclone was approximately $US9930 (including productivity gains [i.e. $US67.83 / 0.006831]) and $US36 894 (excluding productivity gains [i.e. $US252.02 / 0.006831]). Sensitivity analyses using a variety of scenarios suggested that eszopiclone is generally cost effective.

CONCLUSIONS

This analysis suggested that long-term eszopiclone treatment was cost effective over the 6-month study period, particularly when the impact on productivity costs is considered. Given the increasing interest in new pharmacological interventions to manage insomnia, payers and clinicians alike should carefully consider the balance of health and economic benefits that these interventions offer. Accordingly, additional research in this area is warranted.

The cost-effectiveness of mycophenolate mofetil as firstline therapy in active lupus nephritis

OBJECTIVES

Systemic lupus erythematosus (SLE) is an autoimmune disorder that can affect any system of the body. Involvement of the kidneys, lupus nephritis (LN), affects up to 50% of SLE patients during the course of their disease, and is characterized by periods of active disease (flares) and remission. For more severe nephritis, an induction course of immunosuppressive therapy is recommended. Options include intravenous cyclophosphamide (IVC) or mycophenolate mofetil (MMF), followed by a maintenance course, typically of azathioprine. The objective of this study is to determine which therapy results in better quality of life (QoL) for patients and which represents best value for money for finite health service resources.

METHODS

A patient-level simulation model is developed to estimate the costs and quality-adjusted life-years (QALYs) of a patient treated with IVC or MMF for an induction period of six months. Efficacy, QoL, resource use and cost data are extracted from the literature and standard databases and supplemented with expert opinion where necessary.

RESULTS

On average, the model predicts MMF to result in improved QoL compared with IVC. MMF is also less expensive than IVC, costing pound 1600 (euro 2400; US$ 3100) less over the period, based on 2005 NHS prices. The major determinant and cost driver of this result is the requirement for a day-case procedure to administer IVC. Sensitivity analysis shows an 81% probability that MMF will be cost-effective compared with IVC at a willingness to pay of pound 30,000 (euro 44,700; US$ 58,500) per QALY gained.

CONCLUSION

MMF is likely to result in better QoL and be less expensive than IVC as induction therapy for LN.

Sequential medication strategies for postherpetic neuralgia: a cost-effectiveness analysis

Several medications are recommended for relief of postherpetic neuralgia (PHN). A sequential treatment algorithm has been suggested, but its cost-effectiveness is unclear. We developed a decision model to estimate the cost-effectiveness of this algorithm compared with other sequential medication strategies in 70-year-olds with PHN, using literature data to model medication-related PHN relief while also accounting for severe medication side effects. Hypothetical patients with and without coronary artery disease (CAD) were considered separately, with and without localized pain. Sequential medication switches occurred as the result of inadequate relief or intolerable side effects. Probabilistic sensitivity analyses were performed to estimate the favorability of each medication early in treatment sequences. In patients without CAD, tricyclic and gabapentin were equally favored as initial therapy if mortality with tricyclic use was not increased, but gabapentin was strongly favored if it was. In patients with CAD, gabapentin was overwhelmingly favored. In either patient group, opioids, pregabalin, and tramadol were not favored as initial therapy but were sensible choices later in treatment sequences. The lidocaine patch was a reasonable first choice in patients with localized PHN. Our analysis supports the suggested treatment algorithm, with cost-effectiveness ratios within acceptable ranges for medications given sequentially, based on literature-based estimates of effectiveness and tolerability.

PERSPECTIVE

This article examines the cost-effectiveness of recommended sequential treatment strategies for postherpetic neuralgia. This decision analysis-based synthesis of effectiveness and cost data found that recommended treatment algorithms are also economically reasonable.

A Registry of the Aetiology and Costs of Neuropathic Pain in Pain Clinics

OBJECTIVE

The aim of this study was to determine health resource consumption and costs in patients with neuropathic pain managed in pain clinics in Spain.

METHODS

This was a retrospective, cross-sectional study performed in 2004 in 18 pain clinics across Spain. Consecutive neuropathic pain patients were recruited between April and December 2004. Demographic data, type and cause of neuropathic pain, source of referral and utilisation of health resources (treatments, medical visits, hospital admissions, etc.) were collected. Direct medical costs were estimated using 2004 prices. Descriptive statistics and ANCOVA models were used for significance.

RESULTS

The study included 504 patients with neuropathic pain of broad aetiologies (44% radiculopathies, 21% neuralgias, 11% neuropathies, 7% entrapment syndromes, 5% complex regional painful syndrome, 4% central pain), aged 57.8 +/- 0.7 years (mean +/- SE), 57.6% of whom were women. The mean time since diagnosis was 23.7 +/- 26.8 months. Two groups of patients according to type of pain management were also identified: those referred to pain clinics for pain control from primary-care/other specialists (r-PC, n = 326) and those primarily managed at pain clinics (p-PC, n = 178). The adjusted mean monthly total cost was 363 euros per patient with no statistically significant differences between type of care: 376 euros (p-PC) versus 344 euros (r-PC) [p = 0.626]. Acquisition monthly mean drug costs were higher in the p-PC group: 131 euros (34.8% of total costs) versus 80 euros (23.3%) per patient (p = 0.0001). However, emergency-room visits, primary-care visits and number of treatment drugs were significantly higher in the r-PC group: 0.27, 0.20 and 2.90 visits/drugs per patient per month versus 0.13, 0.10 and 2.50, respectively (p < 0.01 in all cases). There were also more diagnostic tests and specialised physician visits and higher hospitalisation costs in r-PC subjects (differences not statistically significant).

CONCLUSIONS

Neuropathic pain results in a substantial utilisation of health resources, particularly by patients referred by primary-care/other specialists to pain clinics for pain control. However, compared with subjects whose pain is primarily managed in pain clinics, the extra health costs arising from drug acquisition observed in such patients are offset by lower costs of the other components of pain management, producing similar mean monthly total costs.

Cost-effectiveness of ocular interventions

The cost-effectiveness of ophthalmic interventions has become increasingly important as the US health care budget continues to grow. During the past two decades, a methodology rooted in utility analysis has provided a way to objectively assess the value of an intervention for a specific disease. Specifically within the field of ophthalmology, there is a growing body of literature on utility analysis using patient preference-based outcomes for ophthalmic disease. This has led the way to combining costs with utility values to derive a cost-utility analysis, or cost-effectiveness, for a given ophthalmic procedure. This article outlines this methodology, provides a reference-case example for initial cataract surgery, and describes a comparative study of the value associated with interventions within the field of ophthalmology and across other medical specialties.

Health care economic analyses and value-based medicine

Health care economic analyses are becoming increasingly important in the evaluation of health care interventions, including many within ophthalmology. Encompassed with the realm of health care economic studies are cost-benefit analysis, cost-effectiveness analysis, cost-minimization analysis, and cost-utility analysis. Cost-utility analysis is the most sophisticated form of economic analysis and typically incorporates utility values. Utility values measure the preference for a health state and range from 0.0 (death) to 1.0 (perfect health). When the change in utility measures conferred by a health care intervention is multiplied by the duration of the benefit, the number of quality-adjusted life-years (QALYs) gained from the intervention is ascertained. This methodology incorporates both the improvement in quality of life and/or length of life, or the value, occurring as a result of the intervention. This improvement in value can then be amalgamated with discounted costs to yield expenditures per quality-adjusted life-year ($/QALY) gained. $/QALY gained is a measure that allows a comparison of the patient-perceived value of virtually all health care interventions for the dollars expended. A review of the literature on health care economic analyses, with particular emphasis on cost-utility analysis, is included in the present review. It is anticipated that cost-utility analysis will play a major role in health care within the coming decade.

A cost-utility analysis of therapy for amblyopia

OBJECTIVE

Evaluation of the incremental cost-effectiveness of therapy for amblyopia.

DESIGN

Cost-utility reference-case analysis.

METHODS

A cost-utility analysis was performed from a third-party insurer perspective by using decision analysis, evidence-based data from the literature, and patient preference-based time trade-off utility values.

DATABASE

Patient-derived time trade-off ocular utility values and the American Academy of Ophthalmology Preferred Practice Pattern guidelines for the treatment of amblyopia.

INTERVENTION

Treatment of childhood amblyopia using medical and surgical therapies per the American Academy of Ophthalmology Preferred Practice Pattern.

MAIN OUTCOME MEASURE

Dollars (year 2001 nominal U.S. dollars) expended per quality-adjusted life-year ($/QALY) gained.

RESULTS

Treatment for amblyopia resulted in a $/QALY gained of $2281 with a discount rate of 3% for costs and outcomes. Sensitivity analysis, varying costs and utility values by 10%, resulted in a $/QALY gained range from $2053 to $2509.

CONCLUSIONS

When compared with other interventions in health care, therapy for amblyopia seems to be highly cost-effective. This information is increasingly important for health care policy makers.

Pharmacoeconomics of antiviral therapies for Herpes zoster infections

Herpes zoster is a common problem, particularly in the elderly, that can lead to postherpetic neuralgia - a significant source of suffering and diminished quality of life. Antiviral medications diminish acute and chronic symptoms of zoster, but whether the relatively high cost of these medications is worth their beneficial effects is controversial. This review updates our prior analysis, synthesizing evidence on the clinical features and costs of zoster and its sequellae, as well as the effects of antiviral therapy, using decision analysis techniques. We find antiviral therapy economically reasonable in immunocompetent adults for whom treatment is clinically recommended: severely symptomatic acute zoster in any adult and milder zoster in adults of 50-60 years or older.