Cost-effectiveness of magnetic resonance-guided focused ultrasound surgery for treatment of uterine fibroids.

OBJECTIVE: To estimate the cost-effectiveness of a treatment strategy for symptomatic uterine fibroids, which starts with Magnetic Resonance-guided Focused Ultrasound Surgery (MRgFUS) as compared with current practice comprising uterine artery embolisation, myomectomy and hysterectomy. DESIGN: Cost-utility analysis based on a Markov model. SETTING: National Health Service (NHS) Trusts in England and Wales. POPULATION: Women for whom surgical treatment for uterine fibroids is being considered. METHODS: The parameters of the Markov model of the treatment of uterine fibroids are drawn from a series of clinical studies of MRgFUS, and from the clinical effectiveness literature. Health-related quality of life is measured using the 6D. Costs are estimated from the perspective of the NHS. The impact of uncertainty is examined using deterministic and probabilistic sensitivity analysis. MAIN OUTCOME MEASURES: Incremental cost-effectiveness measured by cost per quality-adjusted life-year (QALY) gained. RESULTS: The base-case results imply a cost saving and a small QALY gain per woman as a result of an MRgFUS treatment strategy. The cost per QALY gained is sensitive to cost of MRgFUS relative to other treatments, the age of the woman and the nonperfused volume relative to the total fibroids volume. CONCLUSIONS: A treatment strategy for symptomatic uterine fibroids starting with MRgFUS is likely to be cost-effective.

How cost-effective is the treatment of dyslipidemia in patients with diabetes but without cardiovascular disease?

OBJECTIVE: Epidemiological studies have shown that the risk of myocardial infarction (MI) in diabetic patients without cardiovascular disease (CVD) is comparable to the risk of MI in patients with CVD. We used a validated Markov model to compare the long-term costs and benefits of treating dyslipidemia in diabetic patients without CVD versus treating CVD patients without diabetes in the U.S. The generalizability and robustness of these results were also compared across six other countries (Canada, France, Germany, Italy, Spain, and the U.K.). RESEARCH DESIGN AND METHODS: With use of the Cardiovascular Disease Life Expectancy Model, cost effectiveness simulations of simvastatin treatment were performed for men and women who were 40-70 years of age and had dyslipidemia. We forecast the long-term risk reduction in CVD events after treatment. On the basis of the Scandinavian Simvastatin Survival Study results, we assumed a 35% reduction in LDL cholesterol and an 8% rise in HDL cholesterol. RESULTS: In the U.S., treatment with simvastatin for CVD patients without diabetes was cost-effective, with estimates ranging from $8,799 to $21,628 per year of life saved (YOLS). Among diabetic individuals without CVD, lipid therapy also appeared to be cost-effective, with estimates ranging from $5,063 to $23,792 per YOLS. In the other countries studied, the cost effectiveness of treating diabetes in the absence of CVD was comparable to the cost effectiveness of treating CVD in the absence of diabetes. CONCLUSIONS: Among diabetic men and women who do not have CVD, lipid therapy is likely to be as effective and cost-effective as treating nondiabetic individuals with CVD.

Lipid screening to prevent coronary artery disease: a quantitative evaluation of evolving guidelines.

BACKGROUND: There is strong evidence to support the treatment of abnormal blood lipid levels among people with cardiovascular disease. Primary prevention is problematic because many individuals with lipid abnormalities may never actually develop cardiovascular disease. We evaluated the 1998 Canadian lipid guidelines to determine whether they accurately identify high-risk adults for primary prevention. METHODS: Using data from the Lipid Research Clinics and receiver operating characteristic (ROC) curves, we compared the diagnostic performance of the 1998 lipid guidelines when risk factors for coronary artery disease (CAD) were counted versus calculating risk using Framingham risk equations. We also compared the diagnostic accuracy of the 1998 guidelines with guidelines previously published by the National Cholesterol Education Program in the United States and the 1988 Canadian Consensus Conference on Cholesterol and then used Canadian Heart Health Survey data to forecast lipid screening and treatment rates for the Canadian population. RESULTS: The Framingham risk equations were more accurate than counting risk factors for predicting CAD risk (areas under the ROC curves, 0.83 [standard deviation (SD) 0.02] v. 0.77 [SD 0.03], p < 0.05). Risk counting was a particularly poor method for predicting risk for women. The 1998 Canadian guidelines identified high-risk individuals more accurately than the earlier guidelines, but the increased accuracy was largely due to a lower false-positive rate or a higher true-negative rate (i.e., increased test specificity). Using the 1998 lipid guidelines we estimate that 5.9 million Canadians currently free of cardiovascular disease would be eligible for lipid screening and 322,705 (5.5%) would require therapy. INTERPRETATION: Calculating risk using risk equations is a more accurate method to identify people at high risk for CAD than counting the number of risk factors present, especially for women, and the 1998 Canadian lipid screening guidelines are significantly better at identifying high-risk patients than the 1988 guidelines. Many of our findings were incorporated into the new 2000 guidelines.

Cost-effectiveness of treating hyperlipidemia in the presence of diabetes : who should be treated?

BACKGROUND: The objective of this study was to estimate the long-term costs and benefits of treating hyperlipidemia among diabetic patients with and without known cardiovascular disease after validating the Cardiovascular Life Expectancy Model. METHODS AND RESULTS: The model estimates were compared with the Scandinavian Simvastatin Survival Study (4S) and used to estimate the long-term costs and benefits of treatment with simvastatin. Simulations were performed for men and women, 40 to 70 years of age, having pretreatment LDL cholesterol values of 5.46, 4.34, and 3.85 mmol/L (211, 168, and 149 mg/dL). We forecasted the long-term risk of cardiovascular events, the need for medical and surgical interventions, and the associated costs in 1996 US dollars. The model validated well against the observed results of the of the 4S diabetic patients. In this validation, the model estimates fell within the 95% confidence interval of the observed results for 7 of the 8 available end points (coronary deaths, total deaths, and so forth). Treatment with simvastatin for patients with cardiovascular disease is cost-effective for men and women, with or without diabetes. Among diabetic individuals without cardiovascular disease, the benefits of primary prevention were also substantial and the cost-effectiveness ratios attractive across a wide range of assumptions ( approximately $4000 to $40 000 per year of life saved). These conclusions were robust even among diabetics with lower baseline LDL values and smaller LDL reductions as observed in the Cholesterol and Recruitment Events (CARE) trial. CONCLUSIONS: Among adults with hyperlipidemia, the presence of diabetes identifies men and women among whom lipid therapy is likely to be effective and cost-effective even in the absence of other risk factors or known cardiovascular disease.

The cost-effectiveness of exercise training for the primary and secondary prevention of cardiovascular disease.

BACKGROUND: Although exercise training improves cardiovascular disease (CVD) risk factors, few studies have evaluated its potential long-term cost-effectiveness. METHODS: Using the Cardiovascular Disease Life Expectancy Model, a validated disease simulation model, we calculated the life expectancy of average 35- to 74-year-old Canadians found in the 1992 Canadian Heart Health Survey. The impacts of exercise training on cardiovascular risk factors were estimated as a 4% decrease in low-density lipoprotein (LDL) cholesterol, a 5% increase in high-density lipoprotein (HDL) cholesterol, and a 6 mm Hg decrease in both systolic and diastolic blood pressure. Exercise adherence was estimated at 50% for the first year and 30% for all additional years. Costs for a supervised exercise program determined from Canadian sources and converted to US dollars were estimated at $605 for the first year (medical evaluation, stress test, exercise prescription, and program costs) and $367 for all additional years (program costs). For an unsupervised program, the costs were estimated at $311 for the first year and $73 for all additional years. RESULTS: The cost-effectiveness (CE) of an unsupervised exercise program (1996 U.S. dollars) was less than $12,000 per year of life saved (YOLS) for all individuals. The CE of a supervised exercise program was less than $15,000/YOLS for men with CVD, and between $12,000 and $43,000 for women with CVD and men without CVD. CONCLUSIONS: Given the relatively few risks, substantial long-term benefits, and modest costs, an unsupervised exercise training program represents good value for all. A more expensive supervised exercise program is also cost-effective for most individuals with CVD.

The clinical burden of prostate cancer in Canada: forecasts from the Montreal Prostate Cancer Model.

OBJECTIVES: The incidence of prostate cancer is increasing, as is the number of diagnostic and therapeutic interventions to manage this disease. We developed a Markov state-transition model--the Montreal Prostate Cancer Model--for improved forecasting of the health care requirements and outcomes associated with prostate cancer. We then validated the model by comparing its forecasted outcomes with published observations for various cohorts of men. METHODS: We combined aggregate data on the age-specific incidence of prostate cancer, the distribution of diagnosed tumours according to patient age, clinical stage and tumour grade, initial treatment, treatment complications, and progression rates to metastatic disease and death. Five treatments were considered: prostatectomy, radiation therapy, hormonal therapies, combination therapies and watchful waiting. The resulting model was used to calculate age-, stage-, grade- and treatment-specific clinical outcomes such as expected age at prostate cancer diagnosis and death, and metastasis-free, disease-specific and overall survival. RESULTS: We compared the model's forecasts with available cohort data from the Surveillance, Epidemiology and End Results (SEER) Program, based on over 59,000 cases of localized prostate cancer. Among the SEER cases, the 10-year disease-specific survival rates following prostatectomy for tumour grades 1, 2 and 3 were 98%, 91% and 76% respectively, as compared with the model's estimates of 96%, 92% and 84%. We also compared the model's forecasts with the grade-specific survival among patients from the Connecticut Tumor Registry (CTR). The 10-year disease-specific survival among the CTR cases for grades 1, 2 and 3 were 91%, 76% and 54%, as compared with the model's estimates of 91%, 73% and 37%. INTERPRETATION: The Montreal Prostate Cancer Model can be used to support health policy decision-making for the management of prostate cancer. The model can also be used to forecast clinical outcomes for individual men who have prostate cancer or are at risk of the disease.

The economic burden of prostate cancer in Canada: forecasts from the Montreal Prostate Cancer Model.

BACKGROUND: We developed an economic model of prostate cancer management from diagnosis until death. We have used the Montreal Prostate Cancer Model to estimate the total economic burden of the disease in a cohort of Canadian men. METHODS: Using this Markov state-transition simulation model, we estimated the probability of prostate cancer, annual prostate cancer progression rates and associated direct medical costs according to patient age, tumour stage and grade, and treatment modalities in a 1997 cohort of Canadian men. The estimated lifetime costs of prostate cancer included the costs of clinical staging, initial treatments and complications, follow-up cancer therapies, routine outpatient care, and palliative care following metastatic disease. RESULTS: The clinical burden of prostate cancer forecasted using the model was similar to the projections of the National Cancer Institute. In the 1997 cohort of 5.8 million Canadian men between 40 and 80 years old, prostate cancer would be diagnosed in an estimated 701,491 men (12.1%) over their lifetime. Direct medical costs would total $9.76 billion, or $3.89 billion when discounted 5% annually. INTERPRETATION: The Montreal Prostate Cancer Model indicates that the economic burden of prostate cancer to Canada's health care system will be substantial. Further analyses are needed to identify the most efficient means of treating this disease.

Predicting the short term direct medical costs incurred by patients with rheumatoid arthritis.

OBJECTIVE: With increasing interest in revising the mechanisms of health care funding, the ability to anticipate patients' medical expenditures as well as to identify potentially modifiable predictors would be informative for health care providers, payers, and policy makers. METHODS: Eight hundred fifty-eight patients with rheumatoid arthritis from 2 Canadian centers reported semi-annually on their health services utilization and health status for up to 12 years. Annual direct costs were calculated using 1994 Canadian prices. Regression models for the variation in total direct costs and the individual resource components (i.e., physicians, tests, medications, acute and non-acute hospital care) were estimated using previous values of age, sex, disease duration, education, methotrexate availability, employment status, global well being, pain, duration of morning stiffness, and functional disability as predictor variables. The models were developed using all available data except the last 2 observations (i.e., data collected on the last 2 self-report questionnaires) from each patient, which were reserved for model validation. The predictive abilities of the models were assessed by comparing the most recent costs with those predicted by the model using values of the predictor variables from the previous time period. Further, to assess whether the models conferred any advantage over cost estimates based only on previous costs, most recent observed costs were also compared with costs observed in the preceding time period. RESULTS: Self-reported indices of either global well being, pain, or functional disability predicted total direct costs as well as the costs of the 5 individual resource components. Being younger, female, disabled from the work force, having shorter disease duration, and receiving more formal education also predicted higher costs in at least on health resource category. However, being older predicted higher acute and non-acute care hospital costs. Regression models incorporating longitudinal data did not perform better than average costs in the preceding time period in predicting future short term costs. CONCLUSION: Global well being, pain, functional disability, and previous costs are the most important predictors of short term direct medical costs. Although we have demonstrated that regression models do not perform better than previous costs in predicting future short term costs, previous costs are a much less informative predictor than health status variables. Variables such as functional disability and pain identify potentially modifiable disease features and suggest interventions that may improve patient well being and reduce costs.

Cost-effectiveness of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors in the secondary prevention of cardiovascular disease: forecasting the incremental benefits of preventing coronary and cerebrovascular events.

OBJECTIVE: To forecast the long-term benefits and cost-effectiveness of lipid modification in the secondary prevention of cardiovascular disease. METHODS: A validated model based on data from the Lipid Research Clinics cohort was used to estimate the benefits and cost-effectiveness of lipid modification with 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) based on results from the Scandinavian Simvastatin Survival Study (4S), including a 35% decrease in low-density-lipoprotein (LDL)-cholesterol levels and an 8% increase in high-density-lipoprotein (HDL)-cholesterol levels. After comparing the short-term outcomes predicted for the 4S with the results actually observed, we forecast the long-term risk of recurrent myocardial infarction, congestive heart failure, transient ischemic attacks, arrhythmias, and strokes and the need for surgical procedures such as coronary artery bypass grafting, catheterization, angioplasty, and pacemaker insertions. Outpatient follow-up care costs were estimated, as were the costs of hospital care and drug therapy. All costs were expressed in 1996 US dollars. RESULTS: The short-term outcomes predicted for the 4S were consistent with the observed results. The long-term benefits of lipid modification among low-risk subjects (normotensive nonsmokers) with a baseline LDL/ HDL ratio of 5 but no other risk factors ranged from $5424 to $9548 per year of life saved for men and $8389 to $13747 per year of life saved for women. In high-risk subjects (hypertensive smokers) with an LDL/HDL ratio of 5, the estimated costs ranged from $4487 to $8532 per year of life saved in men and $5138 to $8389 per year of life saved in women. Assuming that lipid modification has no effect on the risk of stroke, cost-effectiveness increased by as much as 100%. CONCLUSIONS: These long-term cost estimates are consistent with the short-term economic analyses of the published 4S results. The long-term treatment of hyperlipidemia in secondary prevention is forecasted to be cost-effective across a broad range of patients between 40 and 70 years of age. Recognizing the additional effects of lipid changes on cerebrovascular events can substantially improve the cost-effectiveness of treating hyperlipidemia.

Estimating the benefits of modifying risk factors of cardiovascular disease: a comparison of primary vs secondary prevention.

OBJECTIVES: To compare the potential years of life saved (YOLS) associated with risk factor modification in the primary and secondary prevention of cardiovascular disease (CVD). METHODS: The CVD life expectancy model estimates the risk of death due to coronary disease, stroke, and other causes based on the levels of independent risk factors (such as age, blood pressure, and blood lipid levels) found in the cohort of the Lipid Research Clinics. The model was validated by comparing its predictions with the observed fatal outcomes of 9 randomized clinical trials. We then estimated the YOLS associated with treating hyperlipidemia or hypertension among hypothetical patient groups with and without CVD at baseline. We defined high-risk patients as those with 3 risk factors (hyperlipidemia, cigarette smoking, and hypertension) and low-risk patients as those with isolated hypertension or hyperlipidemia. RESULTS: The fatal events predicted by the model were consistent with the clinical trial results. Among men and women with hyperlipidemia without CVD, the forecasted benefits of lipid therapy were substantially greater among high-risk groups vs low-risk groups (4.74-0.78 YOLS vs 2.50-0.25 YOLS, respectively). Among those with CVD, the forecasted benefits of treatment were similar for both high-risk and low-risk groups (4.65-0.65 YOLS vs 3.84-0.58 YOLS, respectively). The results for hypertension therapy also demonstrated greater benefits for high-risk vs low-risk patients undergoing primary prevention therapy (1.34-0.29 YOLS vs 0.85-0.13 YOLS, respectively), and the forecasted benefits in secondary prevention were similar (1.26-0.23 YOLS vs 1.00-0.23 YOLS, respectively). CONCLUSIONS: The clinical approach to risk factor modification in primary prevention should be different from that in secondary prevention. The forecasted benefits of therapy among patients without CVD are greatest in the presence of other risk factors. Among those with CVD, the benefits of therapy are equivalent, thereby obviating the need to target high-risk patients.

Direct and indirect medical costs incurred by Canadian patients with rheumatoid arthritis: a 12 year study.

OBJECTIVE: To perform the first prospective longitudinal study of direct (health services utilized) and indirect costs (diminished productivity represented by income loss) incurred by patients with rheumatoid arthritis (RA) in Saskatoon and Montreal, followed for up to 12 and 4 years, respectively. METHODS: 1063 patients reported on health status, health services utilization, and diminished productivity every 6 months. RESULTS: Annual direct costs were $3788 (1994 Canadian dollars) in the late 1980s and $4656 in the early 1990s. Given that the average age exceeded 60 years, few participated in labor force activities or considered themselves disabled from the labor force and their indirect costs were substantially less, $2165 in the late 1980s and $1597 in the early 1990s. Institutional stays and medications made up at least 80% of total direct costs. Lengths of stay in acute care facilities remained constant, but the rate of hospitalization increased in the early 1990s, increasing average hospital costs per patient from $1563 in the late 1980s to $2023 in the early 1990s. For nonacute care facilities, rate of admission as well as length of stay increased over time, increasing costs per patient in Saskatoon 5-fold, from $291 to $1605. Those with greater functional disability incurred substantially higher direct and those under 65 years incurred higher indirect costs. CONCLUSION: Direct costs are higher than indirect costs. The major component is due to institutional stays that, in contrast to other direct cost components, is increased in the older and more disabled. Measures to reduce longterm disability by earlier, more aggressive intervention have the potential to produce considerable cost savings. However, it is unknown which strategies will have the greatest effect on outcome and accordingly, how resources can be optimally allocated.

The cost-effectiveness of HMG-CoA reductase inhibitors to prevent coronary heart disease. Estimating the benefits of increasing HDL-C.

OBJECTIVE: To evaluate the lifetime cost-effectiveness of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors for treatment of high blood cholesterol levels. DESIGN: We added cost data to a validated coronary heart disease (CHD) prevention computer model that estimates the benefits of lifelong risk factor modification. The updated model takes into account the costs of cholesterol reduction, the savings in CHD health care costs attributable to intervention, the additional non-CHD costs resulting from patients' living longer, and the beneficial effects of reducing CHD risk by reducing total cholesterol and increasing high-density lipoprotein cholesterol (HDL-C). PATIENTS: Men and women aged 30 to 70 years who were free of CHD, had total cholesterol levels equal to the 90th percentile of the US distribution in their age and sex group, had HDL-C levels equal to the mean of the US distribution in their age and sex group, and were either with or without additional CHD risk factors. INTERVENTION: Use of 20 mg of lovastatin per day, which on average reduces total serum cholesterol by 17% and increases HDL-C by 7%. MAIN OUTCOME MEASURES: Cost per year of life saved after discounting benefits and costs by 5% annually. RESULTS: The increase in HDL-C associated with lovastatin lowered cost-effectiveness ratios by approximately 40%, such that the treatment of hypercholesterolemia was relatively cost-effective for men (as low as $20,882 per year of life saved at age 50 years) and women ($36,627 per year of life saved at age 60 years) with additional risk factors. Non-CHD costs resulting from longer life expectancy after intervention added at most 23% to the cost-effectiveness ratios for patients who began treatment at age 70 years, and as little as 3% for patients at age 30 years. CONCLUSION: The cost-effectiveness of HMG-CoA reductase inhibitors varied widely by age and sex and was sensitive to the presence of non-lipid CHD risk factors. The additional non-CHD costs due to increased life expectancy may be significant for the elderly. Accounting for the drug effects of raising HDL-C levels increased the proportion of the population for which medication treatment was relatively cost-effective.

Economic impact of HIV infection and coronary heart disease in immigrants to Canada.

OBJECTIVE: To compare the direct health care costs of illnesses associated with the human immunodeficiency virus (HIV) and of coronary heart disease (CHD) in immigrants to Canada. DESIGN: Comparative cost analysis. PARTICIPANTS: All people who immigrated to Canada in 1988. The numbers with HIV infection and CHD were estimated from country-specific HIV seroprevalence data and national CHD mortality statistics and data from the Framingham study. Health care costs, projected over the 10 years after immigration, were calculated on the basis of data from the Hospital Medical Records Institute and provincial fee schedules. RESULTS: Of the 161,929 immigrants in 1988, 484 were estimated to be HIV positive. The total cost of treatment of HIV-related illnesses from 1989 to 1998 (discounted at 3%) would be $18.5 million: $17.1 million would be spent on the outpatient and inpatient care of the HIV-positive immigrants, $1.0 million on care of the subsequently infected sexual partners and $0.4 million on care of the HIV-positive children born to seropositive immigrant women. In comparison, CHD would develop in 2558 immigrants during the same 10-year period. The total CHD costs would be $21.6 million: $8.4 million would be spent on treating myocardial infarction, $3.2 million on coronary artery bypass grafting, $1.6 million on pacemaker insertion and $8.4 million on treating other CHD events. CONCLUSIONS: The economic impact of HIV infection in immigrants to Canada is similar to that of CHD. This comparison identifies an important shortcoming in current immigration policy: economic considerations can be arbitrarily applied to certain diseases, thereby discriminating against specific groups of immigrants.

HIV antibody screening among immigrants: a cost-benefit analysis.

To assess the economic impact of HIV (human immunodeficiency virus) antibody screening among potential immigrants on Canada's health care system we estimated the costs and benefits of such screening among the 160 135 immigrants who entered Canada in 1988 using the in-hospital costs of treating AIDS (acquired immune deficiency syndrome) over the 10 years after immigration. This economic model was based on current international HIV seroprevalence data, Canadian immigration statistics and estimates of disease progression. Between 343 and 862 of the immigrants were estimated to have been HIV seropositive; with the use of the enzyme-linked immunosorbent assay and the Western blot technique 310 to 780 of them would have been correctly identified as being seropositive, and 33 to 82 would have been incorrectly classified as being seronegative. Another 16 would have been falsely classified as being seropositive. There would have been 151 to 379 cases of AIDS from 1988 to 1998 among the immigrants identified as being HIV-positive. The estimated total cost of screening would have been $3.3 to $3.4 million. The in-hospital costs of treating HIV-infected immigrants in whom AIDS developed between 1989 and 1998 would have been $5.0 to $17.1 million. Accordingly, screening would have saved $1.7 to $13.7 million over the 10 years after immigration. However, we do not advocate screening on the basis of economic analysis alone and acknowledge that any policy regarding such screening must also incorporate social, legal and ethical considerations.