Paul C. Langley

A review of cost-of-illness studies on obesity

This paper reviews the published cost-of-illness studies on obesity. The medical literature has demonstrated that obesity is an independent risk factor for a number of medical conditions, including diabetes mellitus, hypertension, coronary heart disease, elevated cholesterol levels, depression, musculoskeletal disorders, gallbladder disease, and several cancers. Since these conditions can be costly to treat, obesity clearly has a substantial economic impact. Epidemiologic estimates of the aggregate economic costs associated with specific obesity-related diseases in the United States indicate that the annual burden to society totals in the billions of dollars, representing 5.5% to 7.8% of total health-care expenditures. Although estimates of the costs attributable to obesity differ across studies, the one common finding is that these costs are substantial from a health-policy perspective. The objective of this paper is to identify and review the obesity cost-of-illness literature, address study limitations, and identify key areas for future economic research. This review indicates that the economic burden of obesity has been estimated using a prevalence-based cost-of-illness framework. Areas for future research include estimating the economic burden of obesity using an incidence-based cost-of-illness framework and modeling the association between health-care expenditure and level of obesity using individual-level data, such as medical and pharmacy claims data.

The November 1995 revised Australian guidelines for the economic evaluation of pharmaceuticals.

SummaryIn November 1995, the revised Australian Guidelines for the Economic Evaluation of Pharmaceuticals (‘the Guidelines’) were published. The new document is to be seen as a measured bureaucratic response to the perceived shortcomings of the August 1992 document. The new document sets substantially more demanding and more rigorous evidentiary standards in the reporting of randomised clinical trialş and in the justification of the selected evaluation methodology. It also introduces the requirement for a trial— or efficacy—based preliminary economic evaluation, and it recognises the need. under certain circumstances. to model economic evaluations.Although this document has an immediate appeal to those coming to pharmacoeconomic evaluations from a clinical perspective. the approach taken is unlikely to appeal either to economists (the Guidelines continue to discourage cost—benefit analysis) or to health system evaluators working in a competitive delivery environment (such as the US). The Guidelines. in a US environment. would be seen as not only unreasonable in their evidentiary demands and in the task imposed on evaluators. but limited in their failure to take an explicit modelling or system approach to therapy intervention evaluations.

A pharmacoeconomic assessment of enoxaparin and warfarin as prophylaxis for deep vein thrombosis in patients undergoing knee replacement surgery

This paper examines the relative cost-effectiveness of enoxaparin and warfarin as prophylactic therapy for the prevention of deep vein thrombosis (DVT) in patients undergoing knee replacement surgery in a managed care setting. Although enoxaparin is more expensive than warfarin, it is also more effective in the prevention of DVT after knee replacement surgery. To date there has been no comprehensive assessment of the cost-effectiveness of the alternative agents used for this purpose. This evaluation is undertaken using a decision model that contrasts enoxaparin and warfarin regimens. The model takes explicit account of the incidence of proximal DVT, distal DVT, pulmonary embolism (PE), and major bleeds. The probabilities of clinical events are taken from data from a published randomized, controlled, clinical trial. Key assumptions are that PEs derive only from asymptomatic proximal DVTs and that a false-positive diagnosis of DVT is made in 10% of cases. Unit resource cost data are taken from pharmacoeconomic studies of DVT prophylaxis in hip replacement surgery. The analysis focuses on the actual or expected cost of prophylactic treatment using enoxaparin as opposed to warfarin and, as appropriate measures of cost-effectiveness, the cost per DVT event avoided and the cost per incidence of PE avoided. The expected cost of warfarin prophylaxis is

Formulary submission guidelines for Blue Cross and Blue Shield of Colorado and Nevada. Structure, application and manufacturer responsibilities.

105 less per patient than that of enoxaparin. In terms of expected cost per DVT event avoided, enoxaparin prophylaxis is

A Utility Assessment of Oral and Intravenous Ganciclovir for the Maintenance Treatment of AIDS-Related Cytomegalovirus Retinitis

2525 less than for warfarin; in terms of expected cost per PE avoided, it is

A retrospective analysis of costs and patterns of treatment for external genital warts in the Netherlands

87,201 less. Enoxaparin is more cost-effective than warfarin in terms of both DVT events and PEs avoided in patients who have undergone knee replacement surgery.

Modeling the impact of treatment options in genital warts: Patient-applied versus physician-administered therapies

AbstractFrom 1 January 1999, all requests by pharmaceutical manufacturers and others to Blue Cross and Blue Shield (BCBS) of Colorado and Nevada for the listing of new pharmaceutical products or any proposed change to the formulary status of an existing product must be accompanied by a submission which meets the informational and analytical standards set out in the BCBS Guidelines for Formulary Submissions for Pharmaceutical Product Evaluation. These submission requirements relate both to the anticipated therapeutic impact of a new product and to claims made as to its anticipated pharmacoeconomic impact.The guidelines have been developed because BCBS is concerned that decisions to admit a drug to formulary have been based in the past on incomplete information. In order to rectify this situation (and to meet quality control objectives), it has been decided that all submissions to BCBS should meet a common information standard that describes both the characteristics of the product and its expected impact in a disease or therapeutic area.Unlike guidelines that have been introduced in countries such as Australia and the Canadian Province of Ontario, these guidelines take an explicit systems approach to the case a manufacturer must make before a product is considered for formulary listing. While the notion of systems impact requirements is not new, this is the first time that a managed healthcare system in the US has adopted this explicit perspective and notified manufacturers that traditional pharmacoeconomic evaluations may not meet the information needs of drug purchasers.The purpose of this paper is to describe the BCBS formulary guidelines and to demonstrate how manufacturers are expected to meet the information needs of a systems impact perspective in submissions to the pharmacy and therapeutics committee.

The technology of metered-dose inhalers and treatment costs in asthma: A retrospective study of breath actuation versus traditional press-and-breathe inhalers

The purpose of this study was to determine the magnitude of the difference in patient preferences/utility for intravenous (IV) ganciclovir compared with oral ganciclovir for maintenance treatment of cytomegalovirus (CMV) retinitis.We used a cross-sectional, interviewer-administered time trade-off (TTO) exercise with hypothetical health state descriptions, based upon data from clinical trials and the published literature. The study was conducted in a private clinic in Sydney, Australia, specialising in the care of people with HIV. A total of 80 individuals with HIV infection who had not developed AIDS were administered the TIO instrument. The main outcome measure was the difference between each respondent’s utility score for oral and IV ganciclovir maintenance therapy.When the 80 HIV-positive patients were presented with information on drug efficacy, adverse effects and mode of administration, 60 (75%) preferred oral ganciclovir, 4 patients preferred IV ganciclovir, and 16 were indifferent, The median utilities were 0.837 (oral ganciclovir) and 0.475 (IV ganciclovir). The difference in rankings was statistically significant by Wilcoxon’s signed-ranks test (Z = -6.69, P < 0,00005)The median utility scores suggest that, all other things being equal, individuals with HIV infection would prefer an oral formulation of ganciclovir to IV administration in the event of CMV retinitis infection.

The Accuracy of Asthma and Respiratory Disease Diagnostic Codes in a Managed Care Medical Claims Database

BACKGROUND External genital warts (EGWs) are one of the most common sexually transmitted infections, but little is known about the treatment patterns or resources used in the management of this condition. OBJECTIVE The purpose of this retrospective analysis is to examine the patterns of treatment, resource utilization, and costs for EGWs in 3 dermatology clinics in the Netherlands. METHODS A total of 530 completed episodes of care for EGWs were analyzed to identify patterns of treatment and resources used. Costs of care were calculated based on 4 cost components for each visit: labor costs, material costs, indirect costs, and extra costs. RESULTS Across the 3 sites, men required an average of 5.78 clinic visits to achieve a completed episode of care; women required an average of 6.52 visits. The distribution of visits is highly skewed, however, with a median of 4.56 visits for men and 5.55 for women. More than 80% of patients were initially treated with monotherapy. Podophyllin and cryotherapy were the principal choices for initial therapy. The mean cost, in euros, of completing an episode of care was 221.34 euro for men and 292.29 euro for women. The cost per completed or successful episode of care was 395.92 euro for men and 485.05 euro for women. The distribution of costs was also skewed, with a relatively small group of patients accounting for a considerable proportion of overall costs. Although only 31.4% of male patients recorded > or = 6 visits for a completed episode of care, this group accounted for 57.3% of the total costs of treatment for male patients. Among female patients, 43.4% had > or = 6 visits, which accounted for 73.9% of the total costs of care for female patients. Costs also varied markedly by therapy sequence chosen. Patients who remained on their initial monotherapy or combination therapy had the lowest costs; the extent to which patients switched therapies substantially affected overall costs. For those patients initially treated with podophyllin, the mean total costs of treatment, taking into account the proportion who required a change in therapy, were 204.84 euro for men and 386.38 euro for women. For those initially treated with cryotherapy, the mean cost of treatment was 193.60 euro for men and 169.23 euro for women. CONCLUSION Current treatment options for EGWs do not appear to minimize resource utilization or help achieve complete episodes of care at the lowest possile cost.

PERIPHERAL VASCULAR DISORDERS : A PHARMACOECONOMIC AND QUALITY-OF-LIFE REVIEW

With the availability of new patient-applied treatments for genital and perianal warts, medical providers, physician groups, and health systems are reassessing the role of physician-administered therapies. Two key questions are: how cost-effective are physician- versus patient-administered therapies and, given patient preferences for the convenience and privacy associated with the latter therapies, which of the 2 presently available treatments-imiquimod and podofilox-is most appropriate? The purpose of this article is to examine, from the perspective of the health care purchaser, these questions and to undertake a pharmacoeconomic analysis of the direct cost-effectiveness of therapy options, given targets being set for the outcomes of genital warts therapy. The analysis employs a synthetic, decision-modeling framework in which data on sustained clearance and the direct costs of treatment are drawn from both clinical studies and previous studies on the resources used to support treatment. Once targets are set-and it is proposed here that physicians should aim for at least a 50% sustained clearance rate for genital warts--it becomes clear that in cost per sustained clearance terms, imiquimod, as first-line therapy, is the most cost-effective intervention. If we compare imiquimod with podofilox as first-line therapy (with cryotherapy as the second-line option), the cost per sustained clearance for the imiquimod treatment sequence is