Cost-Effectiveness of Sibutramine in the Treatment of Obesity

Does the Structure Matter? An External Validation and Health Economic Results Comparison of Event Simulation Approaches in Severe Obesity

OBJECTIVES

As obesity-associated events impact long-term survival, health economic (HE) modelling is commonly applied, but modelling approaches are diverse. This research aimed to compare the events simulation and the HE outcomes produced by different obesity modelling approaches.

METHODS

An external validation, using the Swedish obesity subjects (SOS) study, of three main structural event modelling approaches was performed: (1) continuous body mass index (BMI) approach; (2) risk equation approach; and (3) categorical BMI-related approach. Outcomes evaluated were mortality, cardiovascular events, and type 2 diabetes (T2D) for both the surgery and the control arms. Concordance between modelling results and the SOS study were investigated by different state-of-the-art measurements, and categorized by the grade of deviation observed (grades 1-4 expressing mild, moderate, severe, and very severe deviations). Furthermore, the costs per quality-adjusted life-year (QALY) gained of surgery versus controls were compared.

RESULTS

Overall and by study arm, the risk equation approach presented the lowest average grade of deviation (overall grade 2.50; control arm 2.25; surgery arm 2.75), followed by the continuous BMI approach (overall 3.25; control 3.50; surgery 3.00) and by the categorial BMI approach (overall 3.63; control 3.50; surgery 3.75). Considering different confidence interval limits, the costs per QALY gained were fairly comparable between all structural approaches (ranging from £2,055 to £6,206 simulating a lifetime horizon).

CONCLUSION

None of the structural approaches provided perfect external event validation, although the risk equation approach showed the lowest overall deviations. The economic outcomes resulting from the three approaches were fairly comparable.

Incremental cost-effectiveness of evidence-based non-surgical weight loss strategies

Recent medical advancements have led to new modes of treatment for non-surgical weight loss, including several new medications. Our aim was to conduct an incremental cost-effectiveness analysis for all commercially available, evidence-based non-surgical weight loss interventions for people with excess weight. We identified interventions through a systematic review of randomized controlled trials that reported weight loss 12 months from baseline. We then meta-analysed the results, sourced costs and performed an incremental cost-effectiveness analysis from the payer perspective. Cost-effectiveness was presented in terms of cost per kilogram lost and quality-adjusted life years (QALY) gained. We further performed sensitivity analyses on costs and duration of benefits, and a probabilistic sensitivity analysis. Ten interventions were identified for inclusion: six pharmaceutical products (Alli, Xenical, Qsymia, Contrave, Belviq and Saxenda), two lifestyle modification programmes (Weight Watchers Meetings and Online), one food replacement and lifestyle programme (Jenny Craig) and one intragastric balloon system (Orbera). At an incremental cost-effectiveness ratio of $30 071 per additional QALY gained, only Weight Watchers Meetings was cost-effective. Sensitivity analyses revealed that for the medications to become incrementally cost-effective, costs would have to decrease by as much as 91%. Results are highly dependent on duration that benefits are maintained. Despite several newly available interventions, Weight Watchers Meetings is currently the only evidence-based, commercially available, cost-effective option for non-surgical weight loss. Other interventions, specifically medications, are more effective but priced too high to be cost-effective.

Meta- and cost-effectiveness analysis of commercial weight loss strategies

OBJECTIVE

To estimate the incremental cost-effectiveness of clinically proven nonsurgical commercial weight loss strategies for those with BMIs between 25 and 40.

METHODS

We performed a systematic literature review to identify randomized controlled trials of commercially available weight loss studies of at least 1 year in duration. Using the results of these trials and publicly available cost data, we quantified the incremental cost per kilogram of weight loss and per quality adjusted life year (QALY) gained. We then use probabilistic sensitivity analyses to quantify uncertainty in our results.

RESULTS

Based on the literature review, two lifestyle programs (Weight Watchers and Vtrim), one meal replacement program (Jenny Craig), and three pharmaceutical products (Qsymia, Lorcaserin, and Orlistat) were included in the analysis. Average cost per kilogram of weight lost ranged from $155 (95% CI: $110-$218) for Weight Watchers to $546 (95% CI: $390-$736) for Orlistat. The incremental cost per QALY gained for Weight Watchers and Qsymia was $34,630 and $54,130, respectively. All other interventions were prohibitively expensive or inferior in that weight loss could be achieved at a lower cost through one or a combination of the other strategies.

CONCLUSIONS

Results suggest that, in the absence of other considerations and at current market prices, Weight Watchers and Qsymia represent the two most cost-effective strategies for nonsurgical weight loss.

Modelling the economics of type 2 diabetes mellitus prevention: a literature review of methods

Our objective was to review modelling methods for type 2 diabetes mellitus prevention cost-effectiveness studies. The review was conducted to inform the design of a policy analysis model capable of assisting resource allocation decisions across a spectrum of prevention strategies. We identified recent systematic reviews of economic evaluations in diabetes prevention and management of obesity. We extracted studies from two existing systematic reviews of economic evaluations for the prevention of diabetes. We extracted studies evaluating interventions in a non-diabetic population with type 2 diabetes as a modelled outcome, from two systematic reviews of obesity intervention economic evaluations. Databases were searched for studies published between 2008 and 2013. For each study, we reviewed details of the model type, structure, and methods for predicting diabetes and cardiovascular disease. Our review identified 46 articles and found variation in modelling approaches for cost-effectiveness evaluations for the prevention of type 2 diabetes. Investigation of the variables used to estimate the risk of type 2 diabetes suggested that impaired glucose regulation, and body mass index were used as the primary risk factors for type 2 diabetes. A minority of cost-effectiveness models for diabetes prevention accounted for the multivariate impacts of interventions on risk factors for type 2 diabetes. Twenty-eight cost-effectiveness models included cardiovascular events in addition to type 2 diabetes. Few cost-effectiveness models have flexibility to evaluate different intervention types. We conclude that to compare a range of prevention interventions it is necessary to incorporate multiple risk factors for diabetes, diabetes-related complications and obesity-related co-morbidity outcomes.

An economic evaluation of adaptive e-learning devices to promote weight loss via dietary change for people with obesity

Background

The prevalence of obesity is over 25 % in many developed countries. Obesity is strongly associated with an increased risk of fatal and chronic conditions such as cardiovascular disease and type 2 diabetes. Therefore it has become a major public health concern for many economies. E-learning devices are a relatively novel approach to promoting dietary change. The new generation of devices are ‘adaptive’ and use interactive electronic media to facilitate teaching and learning. E-Learning has grown out of recent developments in information and communication technology, such as the Internet, interactive computer programmes, interactive television and mobile phones. The aim of this study is to assess the cost-effectiveness of e-learning devices as a method of promoting weight loss via dietary change.

Methods

An economic evaluation was performed using decision modelling techniques. Outcomes were expressed in terms of Quality-Adjusted Life-Years (QALYs) and costs were estimated from a health services perspective. All parameter estimates were derived from the literature. A systematic review was undertaken to derive the estimate of relative treatment effect.

Results

The base case results from the e-Learning Economic Evaluation Model (e-LEEM) suggested that the incremental cost-effectiveness ratio was approximately £102,000 per Quality-Adjusted Life-Year (QALY) compared to conventional care. This finding was robust to most alternative assumptions, except a much lower fixed cost of providing e-learning devices. Expected value of perfect information (EVPI) analysis showed that while the individual level EVPI was arguably negligible, the population level value was between £37 M and £170 M at a willingness to pay between £20,000 to £30,000 per additional QALY.

Conclusion

The current economic evidence base suggests that e-learning devices for managing the weight of obese individuals are unlikely to be cost-effective unless their fixed costs are much lower than estimated or future devices prove to be much more effective.

Economic evaluations of adult weight management interventions: a systematic literature review focusing on methods used for determining health impacts

BACKGROUND

One of the challenges when undertaking economic evaluations of weight management interventions is to adequately assess future health impacts. Clinical trials commonly measure impacts using surrogate outcomes, such as reductions in body mass index, and investigators need to decide how these can best be used to predict future health effects. Since obesity is associated with an increased risk of numerous chronic diseases occurring at different future time points, modelling is needed for predictions.

OBJECTIVE

To assess the methods used in economic evaluations to determine health impacts of weight management interventions and to investigate whether differences in methods affect the cost-effectiveness estimates.

METHODS

Eight databases were systematically searched. Included studies were categorized according to a decision analytic approach and effect measures incorporated.

RESULTS

A total of 44 articles were included; 21 evaluated behavioural interventions, 12 evaluated surgical procedures and 11 evaluated pharmacological compounds. Of the 27 papers that estimated future impacts, eleven used Markov modelling, seven used a decision tree, five used a mathematical application, two used patient-level simulation and the modelling method was unclear in two papers. The most common types of effects included were co-morbidity treatment costs, heath-related quality of life due to weight loss and gain in survival. Only 12 of the studies included heath-related quality of life gains due to reduced co-morbidities and only one study included productivity gains. Despite consensus that trial-based analysis on its own is inadequate in guiding resource allocation decisions, it was used in 39% of the studies. Several of the modelling papers used model structures not suitable for chronic diseases with changing health risks. Three studies concluded that the intervention dominated standard care; meaning that it generated more quality-adjusted life-years (QALYs) for less cost. The incremental costs per QALY gained varied from $US235 to $US56,836 in the remaining studies using this outcome measure. An implicit hypothesis of the review was that studies including long-term health effects would illustrate greater cost effectiveness compared with trial-based studies. This hypothesis is partly confirmed with three studies arriving at dominating results, as these reach their conclusion from modelling future co-morbidity treatment cost savings. However, for the remaining studies there is little indication that decision-analytic modelling disparities explain the differences.

CONCLUSIONS

This is the first literature review comparing methods used in economic evaluations of weight management interventions, and it is the first time that observed differences in study results are addressed with a view to methodological explanations. We conclude that many studies have methodological deficiencies and we urge analysts to follow recommended practices and use models capable of depicting long-term health consequences.

The effect of weight loss on changes in health-related quality of life among overweight and obese women with urinary incontinence

OBJECTIVE

To estimate the effect of change in weight and change in urinary incontinence (UI) frequency on changes in preference-based measures of health-related quality of life (HRQL) among overweight and obese women with UI participating in a weight loss trial.

METHODS

We conducted a longitudinal cohort analysis of 338 overweight and obese women with UI enrolled in a randomized clinical trial comparing a behavioral weight loss intervention to an educational control condition. At baseline, 6, and 18 months, health utilities were estimated using the Health Utilities Index Mark 3 (HUI3), a transformation of the SF-36 to the preference-based SF-6D, and the estimated Quality of Well-Being (eQWB) score (a summary calculated from the SF-36 physical functioning, mental health, bodily pain, general health perceptions, and role limitations-physical subscale scores). Potential predictors of changes in these outcomes were examined using generalized estimating equations.

RESULTS

In adjusted multivariable models, weight loss was associated with improvement in HUI3, SF-6D, and eQWB at 6 and 18 months (P < 0.05). Increases in physical activity also were independently associated with improvement in HUI3 (P = 0.01) and SF-6D (P = 0.006) scores at 18 months. In contrast, reduction in UI frequency did not predict improvements in HRQL at 6 or 18 months.

CONCLUSION

Weight loss and increased physical activity, but not reduction in UI frequency, were strongly associated with improvements in health utilities measured by the HUI3, SF-6D, and eQWB. These findings provide important information that can be used to inform cost-utility analyses of weight loss interventions.

The economics of childhood obesity

In the past few decades, obesity rates among American children have skyrocketed. Although many factors have played a part in this unhealthy increase, this paper focuses on how economic policies may be contributing to our children's growing girth and how these policies might be altered to reverse this trend. It examines the economic causes and consequences of obesity, the rationales for government intervention, the cost-effectiveness of various policies, and the need for more research funding.

Cost-effectiveness of medical nutrition therapy and therapeutically designed meals for older adults with cardiovascular disease

BACKGROUND

Many older adults experience hyperlipidemia and hypertension, but there is little information about whether medical nutrition therapy (MNT) or therapeutic meals have independent or joint beneficial effects on older adults with these diagnoses.

OBJECTIVE

To assess the cost-effectiveness of MNT and therapeutic meals for older adults with hyperlipidemia and/or hypertension.

DESIGN

A 1-year prospective four-arm controlled randomized community-based clinical trial.

SUBJECTS/SETTING

Participants were people ages 60 years or older residing in community settings who were medically diagnosed with either hypertension or hyperlipidemia. They were recruited through a number of venues beginning in May 2003.

INTERVENTION

The 321 eligible individuals were assigned to one of four arms: (a) a literature control group, (b) a therapeutic meal group that received seven diagnosis-appropriate therapeutic meals a week, (c) an MNT group, and (d) an MNT-plus-therapeutic meal group.

MAIN OUTCOME MEASURE

The outcome measure was quality-adjusted life-years (QALYs). Costs included both intervention and medical costs.

STATISTICAL ANALYSES

Estimations of separate models of costs and QALYs facilitated the construction of incremental cost-effectiveness ratios. Net benefit analysis produced the probability that each intervention was cost-effective given different values for society's willingness to pay for a QALY.

RESULTS

Therapeutic meals are cost-effective. Using the net benefit approach and a willingness to pay of $109,000 per QALY, the probability that the therapeutic meal delivery program is cost-effective is 95% and for MNT the probability is 90%. However, the combination of MNT and therapeutic meals did not have an independent significant effect on QALYs.

CONCLUSIONS

Results inform the debate about extending Medicare funding for MNT to individuals with hypertension and hyperlipidemia. Future research should include more individuals who are not currently receiving medications for these diseases.

Delivering the diabetes education and self management for ongoing and newly diagnosed (DESMOND) programme for people with newly diagnosed type 2 diabetes: cost effectiveness analysis

OBJECTIVES

To assess the long term clinical and cost effectiveness of the diabetes education and self management for ongoing and newly diagnosed (DESMOND) intervention compared with usual care in people with newly diagnosed type 2 diabetes.

DESIGN

We undertook a cost-utility analysis that used data from a 12 month, multicentre, cluster randomised controlled trial and, using the Sheffield type 2 diabetes model, modelled long term outcomes in terms of use of therapies, incidence of complications, mortality, and associated effect on costs and health related quality of life. A further cost-utility analysis was also conducted using current "real world" costs of delivering the intervention estimated for a hypothetical primary care trust.

SETTING

Primary care trusts in the United Kingdom.

PARTICIPANTS

Patients with newly diagnosed type 2 diabetes.

INTERVENTION

A six hour structured group education programme delivered in the community by two professional healthcare educators.

MAIN OUTCOME MEASURES

Incremental costs and quality adjusted life years (QALYs) gained.

RESULTS

On the basis of the data in the trial, the estimated mean incremental lifetime cost per person receiving the DESMOND intervention is pound209 (95% confidence interval - pound704 to pound1137; euro251, -euro844 to euro1363; $326, -$1098 to $1773), the incremental gain in QALYs per person is 0.0392 (-0.0813 to 0.1786), and the mean incremental cost per QALY is pound5387. Using "real world" intervention costs, the lifetime incremental cost of the DESMOND intervention is pound82 (- pound831 to pound1010) and the mean incremental cost per QALY gained is pound2092. A probabilistic sensitivity analysis indicated that the likelihood that the DESMOND programme is cost effective at a threshold of pound20 000 per QALY is 66% using trial based intervention costs and 70% using "real world" costs. Results from a one way sensitivity analysis suggest that the DESMOND intervention is cost effective even under more modest assumptions that include the effects of the intervention being lost after one year.

CONCLUSION

Our results suggest that the DESMOND intervention is likely to be cost effective compared with usual care, especially with respect to the real world cost of the intervention to primary care trusts, with reductions in weight and smoking being the main benefits delivered.

Economic evaluation of lifestyle interventions for preventing diabetes and cardiovascular diseases

Lifestyle interventions (i.e., diet and/or physical activity) are effective in delaying or preventing the onset of diabetes and cardiovascular disease. However, policymakers must know the cost-effectiveness of such interventions before implementing them at the large-scale population level. This review discusses various issues (e.g., characteristics, modeling, and long-term effectiveness) in the economic evaluation of lifestyle interventions for the primary and secondary prevention of diabetes and cardiovascular disease. The diverse nature of lifestyle interventions, i.e., type of intervention, means of provision, target groups, setting, and methodology, are the main obstacles to comparing evaluation results. However, most lifestyle interventions are among the intervention options usually regarded as cost-effective. Diabetes prevention programs, such as interventions starting with targeted or universal screening, childhood obesity prevention, and community-based interventions, have reported favorable cost-effectiveness ratios.

A population model evaluating the costs and benefits associated with different oral treatment strategies in people with type 2 diabetes

AIM

The attainment of near-normal glycaemia is an important feature in reducing complications in people with type 2 diabetes. Current treatment pathways advocate a failure-driven therapy algorithm for blood-glucose lowering that leads to the sequential addition of therapies. The addition and combination of multiple blood-glucose lowering agents may be associated with significant side effects, such as weight gain and hypoglycaemia, resulting in a detrimental quality of life. The objective of this study is to quantify the overall costs and quality-adjusted life years (QALY) associated with therapy escalation via oral only treatment strategies with different adverse event profiles as a function of target HbA1c achievement.

METHODS

A previously published model was adapted to run as a non-terminating simulation model. The model is designed to evaluate the cost utility of treatment strategies in a population of type 2 diabetes mellitus patients. Model outputs include incidence of micro- and macrovascular complications, hypoglycaemia and diabetes-specific and all-cause mortality.

RESULTS

The total number of vascular events predicted by the model varied little across the four treatment strategies because of the glycaemic profile associated with each therapy strategy being similar. The strategy with sequential addition of thiazolidinediones (TZDs) and sulphonylureas (SUs) to metformin (MF) was associated with greatest predicted hypoglycaemia burden. The addition of SU and dipeptidyl peptidase (DPP-4) inhibitors to MF was associated with the highest estimated QALYs.

CONCLUSIONS

A treatment strategy involving the sequential addition of SU and TZD to first-line MF therapy is associated with the lowest cost and lowest gain across a population, whereas addition of TZD and SU sequentially to first-line MF therapy resulted in the highest cost and incrementally less QALY gain when compared with treatment strategies involving the addition of a DPP-4 inhibitor and SU to first-line MF (irrespective of the treatment sequence) that were associated with both less cost and greatest QALY gain.

A case study of ex ante, value-based price and reimbursement decision-making: TLV and rimonabant in Sweden

Value-based pricing (VBP) is a method of setting prices for products based on perceived benefits to the consumer. When information is symmetric and freely available and agency is perfect, VBP is efficient and desirable. Because of substantial information asymmetries, medical insurance distortions, and the prescribing monopoly of physicians, VBP is rare for prescription drugs, though a number of countries have recently moved in this direction. Because the potential benefits can be sizable, it is high time for a review of actual VBP-based decision-making in practice. Sweden, with its pharmaceutical benefits board (TLV), was an early adopter of VBP decision-making. We illustrate actual decision-making, thus, using the case of Acomplia for the treatment of obesity in Sweden, with and without the presence of co-morbid conditions. This example has a number of features that will be useful in illustrating the strengths and weaknesses of VBP in actual practice, including multiple indications, a need for not just one but two economic simulation models, considerable sub-group analysis, and requirements for additional evidence development. TLV concluded, in 2006, that Acomplia was cost-effective for patients with a body mass index (BMI) exceeding 35 kg/m2 and patients with a BMI exceeding 28 kg/m2 and either dyslipidemia or type 2 diabetes. Because of uncertainty in some of the underlying assumptions, reimbursement was granted only until 31 December 2008, at which time the manufacturer would be required to submit additional documentation of the long-term effects and cost-effectiveness in order to obtain continued reimbursement. Deciding on reimbursement coverage for pharmaceutical products is difficult. Ex ante VBP assessment is a form of risk sharing, which has been used by TLV to speed up reimbursement and dispersion of effective new drugs despite uncertainty in their true cost-effectiveness. Manufacturers are often asked in return to generate additional health economic evidence that will establish cost-effectiveness as part of ex post review. The alternative is to delay the reimbursement approval until satisfactory evidence is available.

Obesity management interventions: a review of the evidence

The burden of disease associated with the obesity epidemic shortens lives, and prevalence is accelerating. As with other chronic diseases, improved outcomes are associated with effective self-management of obesity across the life span. The disease of obesity, then, fits squarely within the disease management and chronic care models. This article reviews selected interventions, described in peer-reviewed literature, designed to achieve significant weight loss for individuals identified as overweight or obese. The study objective is to provide an overview of the full range of methods and models for weight loss, including some available without medical supervision. The intended audience includes individuals and organizations with an expressed interest in disease management and the chronic care models. Our review identified promising lines of investigation for future research that span diverse medical disciplines applied to obesity. The quality of the studies included in our review was uneven, and compromises the current evidence for effectiveness and efficacy. Generally, our results showed that combination approaches-surgical or pharmacologic, combined with a behavioral intervention-were most likely to be effective.

Cost-effectiveness of a low-calorie diet and orlistat for obese persons: modeling long-term health gains through prevention of obesity-related chronic diseases

OBJECTIVE

Our study estimated the cost-effectiveness of pharmacologic treatment of obesity in combination with a low-calorie diet in The Netherlands.

METHODS

Costs and effects of a low-calorie diet-only intervention and of a low-calorie diet in combination with 1 year of orlistat were compared to no treatment. The RIVM Chronic Disease Model was used to project the differences in quality adjusted life years (QALYs) and lifetime health-care costs because of the effects of the interventions on body mass index (BMI) status. This was done by linking BMI status to the occurrence of obesity-related diseases and by relating quality of life to disease status. Probabilistic sensitivity analysis was employed to study the effect of uncertainty in the model parameters. In univariate sensitivity analysis, we assessed how sensitive the results were to several key assumptions.

RESULTS

Incremental costs per QALY gained were Euro 17,900 for the low-calorie diet-only intervention compared to no intervention and Euro 58,800 for the low-calorie diet + orlistat compared to the low-calorie diet only. Assuming a direct relation between BMI and quality of life, these ratios decreased to Euro 6000 per QALY gained and Euro 24,100 per QALY gained. Costs per QALY gained were also sensitive to assumptions about long-term weight loss maintenance.

CONCLUSIONS

Cost-effectiveness ratios of interventions aiming at weight reduction depend strongly on assumptions regarding the relation between BMI and quality of life. We recommend that a low-calorie diet should be the first option for policymakers in combating obesity.

Cost-effectiveness of pharmacological anti-obesity treatments: a systematic review

AIM

To review economic evaluations of weight loss drugs and compare reported incremental cost-effectiveness ratios (ICERs).

METHODS

A literature search was conducted for cost-effectiveness (CEAs) and cost-utility analyses (CUAs) of sibutramine, orlistat and rimonabant.

RESULTS

Fourteen unique articles were identified (11 CUAs and 3 CEAs; 9 orlistat, 4 sibutramine and 1 rimonabant). All used diet and exercise as comparator, whereas none included indirect costs. Time horizons varied from treatment period only (1-4 years) to 80 years (median 7.5 years). Longer studies modeled effects on diabetes, micro- and macrovascular complications, coronary heart disease and death. Of the CUAs, the median ICER was 16,000 euro(2007)/QALY (quality-adjusted life-year; range 10,000-88,000), with the worst cost-effectiveness when recommended stop rules for non-responding patients were not applied. All studies but three were funded by the manufacturing company, and the median ICER was considerably higher for independent than for sponsored analyses (62,000 euro vs 15,000 euro/QALY). However, two of the three independent CUAs did not use recommended stop rules, as compared with one of eight manufacturer-sponsored analyses. The results were most sensitive to assumptions regarding weight loss sustainability and utility per kilogram lost. Side effects and dropout because of reasons other than lack of efficacy were generally not incorporated.

CONCLUSION

Published economic evaluations indicate that orlistat, sibutramine and rimonabant are within the range of what is generally regarded as cost-effective. Uncertainty remains about weight loss sustainability, utility gain associated with weight loss and extrapolations from transient weight loss to long-term health benefits. Modeling of head-to-head comparisons and attrition is needed, as are analyses conducted independently of manufacturing companies.

The impact of body weight on patient utilities with or without type 2 diabetes: a review of the medical literature

BACKGROUND

Weight gain is a common side effect of many therapies for type 2 diabetes (T2DM). Selecting utility values for incorporation into cost-utility analyses (CUAs) of T2DM therapies is difficult because of variations in methodologies to elicit utilities and other study limitations.

METHODS

A review of the medical literature was conducted to identify studies assessing the impact of body weight on patient utility.

RESULTS

Eighteen articles presented either: 1) utility values by body-mass index (BMI) or body weight, or 2) the change in utility scores or quality-adjusted life-years based on unit changes in BMI or body weight. Regardless of the study population or methodology used to elicit utility scores, all studies reviewed found that as body weight increased, patient utility decreased. Utility scores obtained using standard gamble were generally higher than those using time trade-off(TTO) or the EQ-5D. Most studies reported utility scores stratified by BMI and used regression analyses to attribute the difference in utility scores to differences in weight while controlling for other factors. Studies generally assumed a constant change in utility occurs with a one unit change in BMI. Recent studies, however, demonstrate the magnitude of changes in utility may vary depending on 1) valuing weight loss versus weight gain; 2) valuing a small or large change in body weight; and 3) baseline BMI.

CONCLUSIONS

Various utility values associated with body weight using different methodologies have been published. Careful consideration should be given to determine the most appropriate utility values to use in CUAs of T2DM therapies.

Cost-utility analysis of rimonabant in the treatment of obesity

OBJECTIVE

To estimate the incremental cost-utility ratio (ICUR) of rimonabant 20 mg/day in the treatment of obesity from a third-party payer's perspective.

METHODS

Pooled data from three randomized clinical trials were used to develop a decision tree with five treatment alternatives: 1- and 2-year treatment with rimonabant, 2-year placebo, 1-year rimonabant followed by 1-year placebo, and no treatment. All alternatives, except no treatment, were accompanied by lifestyle interventions. Treatment benefits included gains in quality-adjusted life-years (QALYs) and reduced incidence of type-2 diabetes mellitus and coronary heart disease (CHD). Drug acquisition cost was based on the average wholesale price of a comparator drug minus 15%. One-way and probabilistic sensitivity analyses were conducted to assess the stability of the base-case results.

RESULTS

One-year rimonabant and 1-year rimonabant followed by placebo were extensively dominated. Rimonabant for 2 years showed an average weight reduction of 8.49 kg, a body mass index reduction of 2.98 kg/m(2) and reduced waist circumference by 8.24 cm (placebo: 3.55 kg, 1.22 kg/m(2), 4.18 cm). Two-year rimonabant was associated with a relative reduction in the 5-year incidence of CHD by 7.15% and of diabetes by 9.28%. Incremental benefits (costs) were 0.0984 QALYs ($5209) compared to no treatment and 0.0581 QALYs ($4182) compared to placebo, producing ICURs of $52,936/QALY (95% confidence interval $39K-$69K) and $71,973/QALY ($51K-$98K), respectively.

CONCLUSIONS

Rimonabant combined with lifestyle interventions has the potential to decrease the rate of obesity-related comorbidities and improve health-related quality of life, albeit at considerable cost.

Health economic evaluation of controlled and maintained physical exercise in the prevention of cardiovascular and other prosperity diseases

OBJECTIVES

Several studies and reports support the health benefits of frequent physical exercise, on the condition that this exercise is controlled and maintained. Given the scarce resources that can be spent on health and health care, the objective of this study was to evaluate the long-term health and economic outcomes of controlled and maintained physical exercise in a fitness setting.

METHODS

A 25-year Markov model with a 12-month cycle-length and states representing diabetes, coronary heart disease, stroke, colon cancer and breast cancer was developed to predict cumulative costs and QALYs (quality adjusted life years) for three defined population cohorts, of different risk levels. Physical exercise was thereby compared with no intervention. Reduced risks associated with physical exercise, cost of diseases and loss of quality of life in case of disease were obtained from published literature. Costs were taken from a societal perspective; Belgium was selected as the setting. One way and probabilistic sensitivity analyses were carried out.

RESULTS

For each of the cohorts, physical exercise is predicted to increase the QALYs and to offset a large part of the initial investment. The cost per QALY varies from 2000 to 15,000 Euro per QALY depending on the risk levels, which is better compared with a majority of secondary preventions that are currently publicly financed.

CONCLUSION

Controlled and maintained physical exercise is projected to be cost-effective, which is likely to be explained by its simultaneous effect on several diseases and the associated weight loss, which affects quality of life positively.

The cost-effectiveness of sibutramine in non-diabetic obese patients: evidence from four Western countries

This paper aims to assess the cost-effectiveness of sibutramine in treating obese patients in the Western countries. The model estimates the costs and quality of life benefits directly associated with weight losses combined with the costs and benefits associated with the reduced incidence of coronary heart disease (CHD) and diabetes. The pivotal effectiveness evidence is derived from a German multicentre, double-blind, randomized clinical trial on obese (body mass index >/= 30 Euro kg m(-2)) patients. The incremental cost per quality-adjusted life year ranges from 10,734 Euro in Switzerland to 13,707 Euro in Germany. The total number of CHD events avoided ranges from 1.96 for the UK to 4.49 for Switzerland. The number of diabetes cases avoided is in the region of 3.0 (ranges from 2.58 for Germany to 3.28 for Switzerland). The majority of costs and benefits are accrued through sibutramine treatment and monitoring. Univariate sensitivity analyses show that results are sensitive to changes in the utility directly attributable to weight losses. The results demonstrate that the benefits associated with sibutramine-induced weight losses are obtained at a reasonable cost in each of the settings explored and suggest that sibutramine treatment could be considered as a viable option for pharmacotherapy treatment alongside diet and exercise.

A review of the cost-effectiveness of face-to-face behavioural interventions for smoking, physical activity, diet and alcohol

OBJECTIVE

To assess the evidence for the cost-effectiveness of health behaviour interventions that address the major behavioural risk factors for chronic disease, including smoking, physical inactivity, poor diet, and alcohol misuse.

METHODS

Medical and economic databases were searched for relevant economic evaluations. Studies were critically appraised using a published 35-point checklist, and the results are described using a narrative approach, noting methodological limitations. The review included 64 studies from 1995-2005, including 17 reports on multiple behaviour interventions.

RESULTS

There was considerable variation among the studies by target populations, intervention components, primary outcomes, and economic methods, but the reported incremental cost-effectiveness ratios were consistently low (e.g. <14,000 Euros per quality-adjusted life-year gained for smoking-cessation programmes in 2006 Euros) as compared to certain preventive pharmaceutical and invasive interventions. Interventions targeting high-risk-population subgroups were relatively better value for money as compared to those targeting general populations.

DISCUSSION

In general, the results of this review demonstrate favourable cost-effectiveness for smoking interventions, physical activity interventions and multiple behaviour interventions in high-risk groups. Although alcohol and dietary interventions appeared to be economically favourable, it is difficult to draw conclusions because of the variety in study outcomes. However, methodological limitations weaken the generalizability of findings, and suggest that the results of any given study should be considered carefully when being used to inform resource allocation.

Assessment of clinical and economic benefits of weight management with sibutramine in general practice in Germany

Obesity is associated with major health risks and a high economic burden impacting on health care systems. This study utilises the latest evidence from randomised clinical trials (RCTs) to explore and to assess the cost effectiveness of sibutramine in combination with diet and lifestyle advice compared to diet and lifestyle advice alone for the treatment of obese subjects without comorbidities at baseline in Germany. New evidence from recently published RCTs and post-marketing surveillance studies, including health economic data as well as quality of life (QoL) data, were used to model the long-term outcomes of weight management with sibutramine in German practice. German healthcare costs and new data from over 8,000 patients were analysed based on a recently published model. These new RCT data were used to model weight losses, proportion of responders to treatment, utilities by weight loss and variability in weight regain post-treatment. Costs and QoL benefits associated with weight loss (using SF-36 data from sibutramine trials), reduced incidence of coronary heart disease (using Framingham equations) and diabetes were used to estimate the cost per quality adjusted life year of sibutramine treatment. For 1,000 patients treated with sibutramine for 1 year, extrapolating outcomes over 4 further years, sibutramine is estimated to save 4.18 CHD events, 2.58 diabetes incident cases and give 51.5 more quality-adjusted life years (QALYs). The cost-utility analysis (CUA) estimates 13,706 euro per QALY gained. Results are sensitive to changes in weight loss, rate of weight regain and discounting rate. Although the non-pharmacological weight management programme in the comparator arm yielded higher weight losses than generally observed in clinical practice, these results demonstrate that additional sibutramine treatment is a cost effective therapy for an obese population without comorbidities in Germany. The CUA results are within the range generally accepted as cost effective and should be viewed as conservative when generalizing to settings offering standard non-pharmacological treatment.

Emerging drugs for obesity: linking novel biological mechanisms to pharmaceutical pipelines

Obesity is associated with hypertension, diabetes, dyslipidaemias and metabolic syndrome, and causes substantial morbidity and mortality from cardiovascular and other diseases. The cost to treat obesity and its complications in the US has increased steeply and is currently estimated to be USD 100 billion. Current therapy for obesity is mainly based on changes in lifestyle that often fail. Existing pharmacological treatment is marginally efficient and poorly tolerated. The discovery of leptin and related neural mechanisms of energy metabolism regulation has opened the doors to potential targets for new antiobesity drugs. In this review, new pharmacological targets are discussed and an update on the development of emerging antiobesity drugs is provided. Despite intense investigation, the pipelines for antiobesity drugs in late stages of development are relatively empty. Breakthrough treatments for obesity may take some years to emerge. Clinical trials will be necessary to clarify the impact of new antiobesity drugs on hard cardiovascular and metabolic end points.

Effects of sibutramine in overweight, poorly controlled Chinese female type 2 diabetic patients: a randomised, double-blind, placebo-controlled study

To assess the efficacy of sibutramine 15 mg once daily as weight reduction in overweight and obese (body mass index > 25 kg/m2) Chinese female type 2 diabetic patients and to evaluate the influence of weight loss on diabetic control, a randomised, double-blind, placebo-control, 12-week study was conducted. Chinese female type 2 diabetic patients, poorly controlled glucose levels and HbA(1C) > 8% were randomly assigned to two groups. In addition to their hypoglycaemic agents (maximal doses of sulphonylureas and metformin), one group (n = 30) received a sibutramine 15 mg once daily for 12 weeks, and the other (n = 30) received placebo for the same period. Comparing the changes that occurred after 12 weeks in the sibutramine and placebo groups, the former showed significantly greater reduction in body weight (2.5 vs. 0.1 kg, p < 0.05), fasting plasma insulin level (28.8 vs. 2.4 pmol/l, p < 0.01), 2-h postprandial blood glucose after standard test meal (3.2 vs. 1.1 mmol/l, p < 0.01), insulin resistance (5.1 vs. 0.2, p < 0.01), HbA1C (1.7% vs. 0.2%, p < 0.05), triglyceride (0.43 vs. 0.12 mmol/l, p < 0.05) and total cholesterol (0.52 vs. 0.08 mmol/l, p < 0.05). No significant differences were found between treatment groups in blood pressure and heart rate. The addition of sibutramine to diet and oral hypoglycaemic therapy resulted in significant weight loss and improvement in metabolic parameters in the treatment group. Sibutramine should be considered for use alongside diet and oral hypoglycaemic therapy in Chinese overweight and obese women with poorly controlled type 2 diabetes.