Cost-effectiveness of primary prevention of cardiovascular disease with atorvastatin in type 2 diabetes: results from the Collaborative Atorvastatin Diabetes Study (CARDS).

AIMS/HYPOTHESIS: We estimated the cost-effectiveness of atorvastatin treatment in the primary prevention of cardiovascular disease in patients with type 2 diabetes using data from the Collaborative Atorvastatin Diabetes Study (CARDS). SUBJECTS AND METHODS: A total of 2,838 patients, who were aged 40 to 75 years and had type 2 diabetes without a documented history of cardiovascular disease and without elevated LDL-cholesterol, were recruited from 32 centres in the UK and Ireland and randomly allocated to atorvastatin 10 mg daily (n = 1,428) or placebo (n = 1,410). These subjects were followed-up for a median period of 3.9 years. Direct treatment costs and effectiveness were analysed to provide estimates of cost per endpoint-free year over the trial period for alternative definitions of endpoint, and of cost per life-year gained and cost per quality-adjusted life-year (QALY) gained over a patient's lifetime. RESULTS: Over the trial period, the incremental cost-effectiveness ratio (ICER) was estimated to be 7,608 pounds per year free of any CARDS primary endpoint; the ICER was calculated to be 4,896 pounds per year free of any cardiovascular endpoint and 4,120 pounds per year free of any study endpoint. Over lifetime, the incremental cost per life-year gained was 5,107 pounds and the cost per QALY was 6,471 pounds (costs and benefits both discounted at 3.5%). CONCLUSIONS/INTERPRETATION: Primary prevention of cardiovascular disease with atorvastatin is a cost-effective intervention in patients with type 2 diabetes, with the ICER for this intervention falling within the current acceptance threshold ( 20,000 pounds per QALY) specified by the National Institute for Health and Clinical Excellence (NICE).

Estimating medical care costs under conditions of censoring.

A number of non-parametric estimators have been proposed to calculate average medical care costs in the presence of censoring. This paper assesses their performance both in terms of bias and efficiency under extreme conditions using a medical dataset which exhibits heavy censoring. The estimators are further investigated using artificially generated data. Their variances are derived from analytic formulae based on the estimators' asymptotic properties and these are compared to empirically derived bootstrap estimates. The analysis revealed various performance patterns ranging from generally stable estimators under all conditions considered to estimators which become increasingly unstable with increasing levels of censoring. The bootstrap estimates of variance were consistent with the analytically derived asymptotic variance estimates. Of the two estimators that performed best, one imposes restrictions on the censoring distribution while the other is not restricted by the censoring pattern and on this basis the second may be preferred.

An economic evaluation of atenolol vs. captopril in patients with Type 2 diabetes (UKPDS 54).

AIMS: To compare the net cost of a tight blood pressure control policy with an angiotensin converting enzyme inhibitor (captopril) or beta blocker (atenolol) in patients with Type 2 diabetes. DESIGN: A cost-effectiveness analysis based on outcomes and resources used in a randomized controlled trial and assumptions regarding the use of these therapies in a general practice setting. SETTING: Twenty United Kingdom Prospective Diabetes Study Hospital-based clinics in England, Scotland and Northern Ireland. SUBJECTS: Hypertensive patients (n = 758) with Type 2 diabetes (mean age 56 years, mean blood pressure 159/94 mmHg), 400 of whom were allocated to the angiotensin converting enzyme inhibitor captopril and 358 to the beta blocker atenolol. MAIN OUTCOME MEASURES: Life expectancy and mean cost per patient. RESULTS: There was no statistically significant difference in life expectancy between groups. The cost per patient over the trial period was 6485 UK pounds in the captopril group, compared with 5550 UK pounds in the atenolol group, an average cost difference of 935 UK pounds (95% confidence interval 188 UK pounds, 1682 UK pounds). This 14% reduction arose partly because of lower drug prices, and also because of significantly fewer and shorter hospitalizations in the atenolol group, and despite higher antidiabetic drug costs in the atenolol group. CONCLUSIONS: Treatment of hypertensive patients with Type 2 diabetes using atenolol or captopril was equally effective. However, total costs were significantly lower in the atenolol group. Diabet. Med. 18, 438-444 (2001)

Cost-effectiveness analysis of intensive blood-glucose control with metformin in overweight patients with type II diabetes (UKPDS No. 51).

AIMS/HYPOTHESIS: To estimate the economic efficiency of intensive blood-glucose control with metformin compared with conventional therapy primarily with diet in overweight patients with Type II (non-insulin-dependent) diabetes mellitus. METHODS: Cost-effectiveness analysis based on patient level data from a randomised clinical controlled trial involving 753 overweight (> 120% ideal body weight) patients with newly diagnosed Type II diabetes conducted in 15 hospital-based clinics in England, Scotland and Northern Ireland as part of the UK Prospective Diabetes Study. Subjects were allocated at random to an intensive blood-glucose control policy with metformin (n = 342) or a conventional policy primarily with diet (n = 411). The analysis was based on the cost of health care resources associated with metformin and conventional therapy and the estimated effectiveness in terms of life expectancy gained from within-trial effects. RESULTS: Intensive blood-glucose control with metformin produced a net saving of 258 Pounds per patient (1997 United Kingdom prices) over the trial period (median duration of 10.7 years) due to lower complication costs, and increased life expectancy by 0.4 years (costs and benefits discounted at 6%). CONCLUSIONS/INTERPRETATION: As metformin is both cost-saving in the United Kingdom and extends life expectancy when used as first line pharmacological therapy in overweight Type II diabetic patients, its use should be attractive to clinicians and health care managers alike.

Centre-specific or average unit costs in multi-centre studies? Some theory and simulation.

Costing issues are increasingly being addressed in multi-centre studies. In this paper, two methods for collecting costing information are compared within a simulated clinical trial setting. One method estimates average treatment costs by applying unit costs averaged across treatment centres to centre-specific volumes of resource use. The second uses centre-specific information for both the unit costs and the resource volumes, and then averages across centres. Using a pre-specified production relation between the different volumes of resource use, and simulating changes in unit costs, it is shown that these two methods result in statistically different estimates of average treatment costs. This finding holds, regardless of the degree of substitutability between the resource volumes, except when considerable uncertainty surrounds treatment centre responses to relative changes in unit costs. The findings suggest that a more cautious approach should be adopted in the collection, calculation and interpretation of treatment costs in multi-centre studies.

Cost effectiveness of an intensive blood glucose control policy in patients with type 2 diabetes: economic analysis alongside randomised controlled trial (UKPDS 41). United Kingdom Prospective Diabetes Study Group.

OBJECTIVE: To estimate the cost effectiveness of conventional versus intensive blood glucose control in patients with type 2 diabetes. DESIGN: Incremental cost effectiveness analysis alongside randomised controlled trial. SETTING: 23 UK hospital clinic based study centres. PARTICIPANTS: 3867 patients with newly diagnosed type 2 diabetes (mean age 53 years). INTERVENTIONS: Conventional (primarily diet) glucose control policy versus intensive control policy with a sulphonylurea or insulin. MAIN OUTCOME MEASURES: Incremental cost per event-free year gained within the trial period. RESULTS: Intensive glucose control increased trial treatment costs by pound 695 (95% confidence interval pound 555 to pound 836) per patient but reduced the cost of complications by pound 957 (pound 233 to pound 1681) compared with conventional management. If standard practice visit patterns were assumed rather than trial conditions, the incremental cost of intensive management was pound 478 (-pound 275 to pound 1232) per patient. The within trial event-free time gained in the intensive group was 0.60 (0.12 to 1.10) years and the lifetime gain 1.14 (0.69 to 1.61) years. The incremental cost per event-free year gained was pound 1166 (costs and effects discounted at 6% a year) and pound 563 (costs discounted at 6% a year and effects not discounted). CONCLUSIONS: Intensive blood glucose control in patients with type 2 diabetes significantly increased treatment costs but substantially reduced the cost of complications and increased the time free of complications.

Where are the economic guidelines coming from?

Economic guidelines recommend methods that should be employed in conducting economic evaluations of healthcare programs. The nature of the efficiency or equity goal underpinning economic guidelines is unclear. What is also unclear is how the methods recommended in the guidelines are linked to the underlying efficiency or equity goal being targeted. If it is unclear what efficiency/equity objectives are being pursued, then it is unlikely that even full implementation of economic guidelines will improve resource allocation.