Cost-effectiveness of intensive glycemic control, intensified hypertension control, and serum cholesterol level reduction for type 2 diabetes

CONTEXT

Several treatment interventions can reduce complications of type 2 diabetes, but their relative cost-effectiveness is not known.

OBJECTIVE

To estimate the incremental cost-effectiveness of intensive glycemic control (relative to conventional control), intensified hypertension control, and reduction in serum cholesterol level for patients with type 2 diabetes.

DESIGN, SETTING, AND PATIENTS

Cost-effectiveness analysis of a hypothetical cohort of individuals living in the United States, aged 25 years or older, who were newly diagnosed as having type 2 diabetes. The results of the United Kingdom Prospective Diabetes Study (UKPDS) and other studies were used to create a model of disease progression and treatment patterns. Costs were based on those used in community practices in the United States.

INTERVENTIONS

Insulin or sulfonylurea therapy for intensive glycemic control; angiotensin-converting enzyme inhibitor or beta-blocker for intensified hypertension control; and pravastatin for reduction of serum cholesterol level.

MAIN OUTCOME MEASURES

Cost per quality-adjusted life-year (QALY) gained. Costs (in 1997 US dollars) and QALYs were discounted at a 3% annual rate.

RESULTS

The incremental cost-effectiveness ratio for intensive glycemic control is $41 384 per QALY; this ratio increased with age at diagnosis from $9614 per QALY for patients aged 25 to 34 years to $2.1 million for patients aged 85 to 94 years. For intensified hypertension control the cost-effectiveness ratio is -$1959 per QALY. The cost-effectiveness ratio for reduction in serum cholesterol level is $51 889 per QALY; this ratio varied by age at diagnosis and is lowest for patients diagnosed between the ages of 45 and 84 years.

CONCLUSIONS

Intensified hypertension control reduces costs and improves health outcomes relative to moderate hypertension control. Intensive glycemic control and reduction in serum cholesterol level increase costs and improve health outcomes. The cost-effectiveness ratios for these 2 interventions are comparable with those of several other frequently adopted health care interventions.

Assessing the impact of complications on the costs of Type II diabetes

AIMS/HYPOTHESIS

'The Cost of Diabetes in Europe-Type II (CODE-2) study' provides the first coordinated attempt to assess the total costs of managing people with Type II (non-insulin-dependent) diabetes mellitus in Europe. Type II diabetes is associated with a number of serious long-term complications, which are a major cause of morbidity, hospitalisation and mortality in diabetic patients.

METHODS

Patients were divided into four broad categories defining their complication status in terms of no complications, one or more microvascular complications, one or more macrovascular complications or one or more of each microvascular and macrovascular complication. The prevalence of complications and associated costs were assessed retrospectively for 6 months.

RESULTS

In total, 72% of patients in the CODE-2 study had at least one complication, with 19% having microvascular only, 10% having macrovascular only and 24% of the total having both microvascular and macrovascular complications. Of patients with microvascular complications, 28% had neuropathy, 20% renal damage, 20% retinopathy and 6.5% required treatment for eye complications. Among the patients with macrovascular complications, 18% had peripheral vascular disease, 17% angina, 12% heart failure and 9% had myocardial infarction. Percutaneous transluminal coronary angioplasty, coronary artery bypass graft or stroke occurred in 3%, 4% and 5% of the patients, respectively. In patients with both microvascular and macrovascular complications, the total cost of management was increased by up to 250% compared to those without complications.

CONCLUSION/INTERPRETATION

Complications have a substantial impact on the costs of managing Type II diabetes. This study has confirmed that the prevention of diabetic complications will not only benefit patients, but potentially reduce overall healthcare expenditure.

Model of complications of NIDDM. II. Analysis of the health benefits and cost-effectiveness of treating NIDDM with the goal of normoglycemia

OBJECTIVE

To analyze the health benefits and economics of treating NIDDM with the goal of normoglycemia.

RESEARCH DESIGN AND METHODS

Incidence-based simulation model of NIDDM was used. Hazard rates for complications were adjusted for glycemia using risk gradients from the Diabetes Control and Complications Trial. Treatment costs were estimated from national survey data and clinical trials. Incremental costs and benefits were expressed in present value dollars (3% discount rate). Life-years were adjusted for quality of life, yielding quality-adjusted life-years (QALYs).

RESULTS

Comprehensive treatment of NIDDM that maintains an HbA1c value of 7.2% is predicted to reduce the cumulative incidence of blindness, end-stage renal disease, and lower-extremity amputation by 72, 87, and 67%, respectively. Cardiovascular disease risk increased by 3% (no effect of treating glycemia is assumed). Life expectancy increased 1.39 years. The cost of treating hyperglycemia increased by almost twofold, which is partially offset by reductions in the cost of complications. The estimated incremental cost/QALY gained is $16,002. Treatment is more cost-effective for those with longer glycemic exposure (earlier onset of diabetes), minorities, and those with higher HbA1c under standard care.

CONCLUSIONS

The incremental effectiveness of treating NIDDM with the goal of normoglycemia is estimated to be approximately $16,000/QALY gained, which is in the range of interventions that are generally considered cost-effective.

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.

The direct medical cost of type 2 diabetes

OBJECTIVE

To describe the direct medical costs associated with type 2 diabetes, as well as its treatments, complications, and comorbidities.

RESEARCH DESIGN AND METHODS

We studied a random sample of 1,364 subjects with type 2 diabetes who were members of a Michigan health maintenance organization. Demographic characteristics, duration of diabetes, diabetes treatments, glycemic control, complications, and comorbidities were assessed by surveys and medical chart reviews. Annual resource utilization and costs were assessed using health insurance claims. The log-transformed annual direct medical costs were fitted by multiple linear regression to indicator variables for demographics, treatments, glycemic control, complications, and comorbidities.

RESULTS

The median annual direct medical costs for subjects with diet-controlled type 2 diabetes, BMI 30 kg/m(2), and no microvascular, neuropathic, or cardiovascular complications were 1,700 dollars for white men and 2,100 dollars for white women. A 10-kg/m(2) increase in BMI, treatment with oral antidiabetic or antihypertensive agents, diabetic kidney disease, cerebrovascular disease, and peripheral vascular disease were each associated with 10-30% increases in cost. Insulin treatment, angina, and MI were each associated with 60-90% increases in cost. Dialysis was associated with an 11-fold increase in cost.

CONCLUSIONS

Insulin treatment and diabetes complications have a substantial impact on the direct medical costs of type 2 diabetes. The estimates presented in this model may be used to analyze the cost-effectiveness of interventions for type 2 diabetes.

An economic analysis of interventions for diabetes

The objective of this article is to stratify interventions for diabetes according to their economic impact. We conducted a review of the literature to select articles that performed a cost-benefit analysis for 17 widely practiced interventions for diabetes. A scale for categorizing interventions according to their economic impact was defined. The 17 interventions were classified as follows: 1) clearly cost-saving, 2) clearly cost-effective, 3) possibly cost-effective, 4) non-cost-effective, or 5) unclear. Clearly cost-saving interventions included eye care and pre-conception care. Clearly cost-effective interventions included nephropathy prevention in type 1 diabetes and improved glycemic control. Possibly cost-effective interventions included nephropathy prevention in type 2 diabetes and self-management training. Non-cost-effective interventions were not identified. Interventions with unclear economic impact included case management, medical nutrition therapy, self-monitoring of blood glucose, foot care, blood pressure control, blood lipid control, smoking cessation, exercise, weight loss, HbA1c measurement, influenza vaccination, and pneumococcus vaccination. Widely practiced interventions for patients with diabetes can be clearly cost-saving and clearly cost-effective. These practices are attractive from both a medical and an economic perspective.

The progressive cost of complications in type 2 diabetes mellitus

BACKGROUND

A substantial proportion of the costs of diabetes treatment arises from treating long-term complications, particularly cardiovascular and renal disease. However, little is known about the progressive cost of these complications. Firmer knowledge would improve diabetes modeling and might increase the financial and organizational support for the prevention of diabetic complications.

METHODS

We analyzed 9 years of clinical data on 11 768 members of a large group-model health maintenance organization who had probable type 2 diabetes mellitus. We ascertained the presence of cardiovascular and renal complications, staged the members progression, and estimated their incremental costs by stage.

RESULTS

We found no significant differences between men and women in the prevalence or staging of complications. Per-person costs increased over baseline ($2033) by more than 50% ($1087) after initiation of cardiovascular drug therapy and/or use of a cardiologist, and by 360% ($7352) after a major cardiovascular event. Abnormal renal function increased diabetes treatment costs by 65% ($1337); advanced renal disease, by 195% ($3979); and end-stage renal disease, by 771% ($15 675). Both cardiovascular and renal diseases were more common among older subjects, but age did not affect the additional costs of these complications. Women had substantially higher medical care costs after controlling for age and presence of complications. Incremental cost estimates based solely on "labeled" events significantly underestimate true incremental cost.

CONCLUSIONS

In an aggregate population, the greatest cost savings would be achieved by preventing major cardiovascular events. For individuals, the greatest savings would be achieved by preventing progression to stage 3 renal disease.

Direct medical costs of complications resulting from type 2 diabetes in the U.S

OBJECTIVE

To estimate direct medical costs of managing the complications of type 2 diabetes.

RESEARCH DESIGN AND METHODS

Costs were estimated for 15 diabetic complications by applying unit costs to typical resource-use profiles. Resource used and unit costs were estimated from many sources, including acute care discharge databases, clinical guidelines, government reports, fee schedules, and peer-reviewed literature. For each complication, the event costs are those associated with resource use that is specific to the acute episode and any subsequent care occurring in the 1st year. State costs are the annual costs of continued management. All costs are expressed in 1996 U.S. dollars.

RESULTS

As expected, the more severe or debilitating events, such as acute myocardial infarction ($27,630 event cost; $2,185 state cost), generate a greater financial burden than do early-stage complications, such as microalbuminuria ($62 event cost; $14 state cost). Yet, complications that are initially relatively low in cost (e.g., microalbuminuria) can progress to more costly advanced stages (e.g., end-stage renal disease, $53,659 state cost); therefore, minor complications should also be considered in any economic analysis of diabetes.

CONCLUSIONS

The recent literature has lacked cost estimates that may be readily translated into patient-level cost inputs for an economic model. Emerging therapies that may reduce the incidence of some diabetic complications will need to be scrutinized economically in today's cost-conscious environment. The cost estimates from this study provide one piece of the economic analysis needed to evaluate these new interventional therapies.

The cost-effectiveness of treating all patients with type 2 diabetes with angiotensin-converting enzyme inhibitors

BACKGROUND

Although guidelines recommend angiotensin-converting enzyme inhibitors for diabetic patients with microalbuminuria, this strategy requires that providers adhere to screening recommendations. In addition, the benefit of angiotensin-converting enzyme inhibitors in normoalbuminuric patients was recently demonstrated.

OBJECTIVE

To evaluate the cost-effectiveness of treating all patients with type 2 diabetes.

DESIGN

Markov model simulating the progression of diabetic nephropathy.

DATA SOURCES

Randomized trials estimating the progression of diabetic nephropathy with and without angiotensin-converting enzyme inhibitors.

TARGET POPULATION

Patients 50 years of age with newly diagnosed type 2 diabetes (fasting plasma glucose level > or = 7.8 mmol/L [140 mg/dL]).

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTIONS

Patients received angiotensin-converting enzyme inhibitors, screening for microalbuminuria, or screening for gross proteinuria.

OUTCOME MEASURES

Lifetime cost, quality-adjusted life expectancy, and marginal cost-effectiveness.

RESULTS OF BASE-CASE ANALYSIS

Screening for gross proteinuria had the highest cost and the lowest benefit. Compared with screening for microalbuminuria, treating all patients was more expensive ($15240 and $14940 per patient) but was associated with increased quality-adjusted life expectancy (11.82 and 11.78 quality-adjusted life-years). The marginal cost-effectiveness ratio was $7500 per quality-adjusted life-year gained.

RESULTS OF SENSITIVITY ANALYSIS

Results were sensitive to the cost, effectiveness, and quality of life associated with angiotensin-converting enzyme inhibitor therapy, as well as age at diagnosis. The model was relatively insensitive to adherence with screening and costs of treating end-stage renal disease.

CONCLUSIONS

Treating all middle-aged diabetic patients with angiotensin-converting enzyme inhibitors is a simple strategy that provides additional benefit at modest additional cost. The strategy assumes that patients meet the older diagnostic criteria for diabetes and makes sense only for those who are not bothered by treatment.

Review of the cost of diabetes complications in Australia, Canada, France, Germany, Italy and Spain

OBJECTIVES

To provide a comprehensive source document on previously published cost data for diabetic complications in Australia, Canada, France, Germany, Italy and Spain for use in a peer-reviewed, validated diabetes model.

METHODS

A search for published cost of diabetes complications data was performed in peer-reviewed journals listed in PubMed and health economic conference proceedings from 1994 to March 2005. Where country specific data were not available, we referred to government websites and local cost experts. All costs were inflated to 2003 Euros (E). Major complication costs are presented.

RESULTS

First year costs of non-fatal myocardial infarction varied between E19277 in Spain and E12292 in Australia. In subsequent years of treatment, this range was E1226 (France) to E203 (Australia). Angina costs were similar across all four countries: E1716 in Australia; E2218 in Canada; E2613 in France; E3342 in Germany; E2297 in Italy; and E2207 in Spain. Event costs of non-fatal stroke were higher in Canada (E23173) than in other countries (Australia E13443; France E11754; Germany E19399; Italy E6583; Spain E4638). Event costs of end-stage renal disease varied depending on the type of dialysis: in Australia (E17188-27552); Canada (E33811-58159); France (E24608-56487); Germany (E46296-68175); Italy (E43075-56717); and Spain (E28370-32706). Lower extremity amputation costs were: E18547 (Australia); E17130 (Canada); E31998 (France); E22096 (Germany); E10177 (Italy); and E14787 (Spain).

CONCLUSIONS

Overall, our search showed costs are well documented in Australia, Canada, France and Germany, but revealed a paucity of data for Spain and Italy. Spanish costs, collected by contacting local experts and from government reports, generally appeared to be lower for treating cardiovascular complications than in other countries. Italian costs reported in the literature were primarily hospitalization costs derived from diagnosis-related groups, and therefore likely to misrepresent the cost of specific complications. Additional research is required to document complication costs in Spain and Italy. Australian and German values were collected primarily by referring to diagnostic related group (DRG) tariffs and, as a result, there may be a need for future economic evaluations measuring the accuracy of the costs and resource utilization in the reported values. These cost data are essential to create models of diabetes that are able to accurately simulate the cumulative costs associated with the progression of the disease and its complications.

Continuum of Renoprotection with Losartan at All Stages of Type 2 Diabetic Nephropathy: A Post Hoc Analysis of the RENAAL Trial Results

Renin angiotensin system inhibitor therapy is seldom offered to individuals who have diabetes and advanced chronic kidney disease because of safety concerns. In this post hoc, secondary analysis of the Reduction of Endpoints in NIDDM with the Angiotensin II Antagonist Losartan (RENAAL) trial, angiotensin antagonism risk/benefit profile was assessed in 1513 individuals with type 2 diabetes and overt nephropathy. Incidence of ESRD, hospitalizations for heart failure, withdrawals for adverse events, and proteinuria during losartan or conventional treatment were compared within three tertiles of baseline serum creatinine concentration (highest, 2.1 to 3.6 mg/dl; middle, 1.6 to 2.0 mg/dl; lowest, 0.9 to 1.6 mg/dl). Losartan decreased the risk of ESRD by 24.6, 26.3, and 35.3% in highest, middle, and lowest tertiles, respectively. For every 100 patients with serum creatinine >2.0, 1.6 to 2.0, or <1.6 mg/dl, respectively, 4 yr of losartan therapy was estimated to save 18.9, 8.4, and 2.9 ESRD events and US$1,502,855, US$1,021,770, and US$528,591 costs for renal replacement therapy. Losartan also decreased the hospitalizations for heart failure by 50.2 and 45.1, in the highest and middle tertile, respectively. Withdrawals for adverse events other than heart failure were comparable between tertiles and treatment groups. Proteinuria decreased more on losartan than on placebo in all tertiles (highest, 24 versus -8%; middle, 16 versus -8%; lowest, 15 versus -10%). In proteinuric individuals with type 2 diabetes, losartan therapy reduced ESRD and hospitalizations for heart failure and was well tolerated at all levels of renal function. Angiotensin II antagonism is a suitable and well-tolerated treatment for individuals with type 2 diabetes even with GFR levels approaching renal replacement therapy.

The effects of treatment on the direct costs of diabetes

Treatment of diabetic complications consumes health care resources. Intensive therapy was shown by the Diabetes Control and Complications Trial (DCCT) to avert complications. Economic analyses and models have been used to evaluate the cost-effectiveness of intensive therapy for people with type 1 and type 2 diabetes. An economic analysis of the DCCT estimated the cost of intensive therapy to be two to three times greater than that of conventional therapy. In contrast, an economic model predicts that intensive therapy, as compared with conventional therapy, could reduce blindness from 34 to 20% or by 41%, end-stage renal disease from 24 to 7% or by 71%, and lower-extremity amputations from 7 to 4% or by 43%. Although intensive therapy is more expensive, when the costs of complications are factored in, it becomes cost-effective for treatment of type 1 diabetes. Similarly, a model to evaluate the cost-effectiveness of intensive therapy for people with type 2 diabetes found that the lifetime costs of general and diabetes-related medical care would be approximately two times greater. However, the reduction in lifetime costs of complications, which would produce substantial reductions in costs of treatment, largely offsets the difference. Intensive therapy for type 1 and type 2 diabetes may be more expensive than conventional therapy, but from an economic perspective, it is comparable in cost to pharmacological therapies for people with hypertension and hypercholesterolemia. From a health system viewpoint, intensive therapy represents a fruitful long-term financial investment.

Cost of managing complications resulting from type 2 diabetes mellitus in Canada

BACKGROUND

Decision makers need to have Canadian-specific cost information in order to develop an accurate picture of diabetes management. The objective of this study is to estimate direct medical costs of managing complications of diabetes. Complication costs were estimated by applying unit costs to typical resource use profiles. For each complication, the event costs refer to those associated with the acute episode and subsequent care in the first year. State costs are the annual costs of continued management. Data were obtained from many Canadian sources, including the Ontario Case Cost Project, physician and laboratory fee schedules, formularies, reports, and literature. All costs are expressed in 2000 Canadian dollars.

RESULTS

Major events (e.g., acute myocardial infarction: 18,635 dollars event cost; 1,193 dollars state cost), generate a greater financial burden than early stage complications (e.g., microalbuminuria: 62 dollars event cost; 10 dollars state cost). Yet, complications that are initially relatively low in cost (e.g., microalbuminuria) can progress to more costly advanced stages (e.g., end-stage renal disease, 63,045 dollars state cost).

CONCLUSIONS

Macrovascular and microvascular complication costs should be included in any economic analysis of diabetes. This paper provides Canadian-based cost information needed to inform critical decisions about spending limited health care dollars on emerging new therapies and public health initiatives.

An economic analysis of captopril in the treatment of diabetic nephropathy. The Collaborative Study Group

OBJECTIVE

The results of a recent clinical trial. The Effect of ACE inhibition on Diabetic Nephropathy, demonstrated that captopril reduced the rate of renal failure, end-stage renal disease (ESRD), and death in patients with IDDM and nephropathy. The purpose of this study was to determine the cost-benefit and cost-effectiveness of captopril as a therapy in patients with IDDM as well as the potential savings for all patients with diabetes and nephropathy.

RESEARCH DESIGN AND METHODS

We used the results from a randomized, placebo-controlled trial comparing captopril (207 patients) with placebo (202 patients), whose purpose was to determine whether captopril has kidney-protecting properties independent of its effect on blood pressure in diabetic nephropathy to develop a model of medical treatment for patients before progression to ESRD. To model the course of illness after progression to ESRD and to extend the model to patients with NIDDM, we used data from the U.S. Renal Data System and published literature. Medical resource cost data were based predominantly upon Medicare reimbursement levels, published wholesale drug prices, and surveying health care providers. The economic model uses a payer perspective to estimate direct cost. The cost to society (indirect cost) associated with lost patient productivity due to ESRD was also estimated. Using this information, we predicted the costs incurred annually and over a lifetime if patients with IDDM and NIDDM and overt nephropathy were treated with either placebo or captopril. We also constructed a model of the overall prevalence of diabetic nephropathy to estimate the aggregate savings in total U.S. health care expenditures.

RESULTS

Treatment with captopril resulted in an absolute direct cost savings or benefit of $32,550 per patient with IDDM over the course of a lifetime compared to treatment with placebo. For patients with NIDDM, the direct cost savings totaled $9,900 per patient. Absolute savings were found for indirect costs as well: $84,390 per patient with IDDM and $45,730 per patient with NIDDM. If captopril therapy were initiated in 1995 for patients with either IDDM or NIDDM and nephropathy, the aggregate health care cost savings (i.e. direct cost savings alone) would be $189 million a year for the year 1999 and $475 million a year in 2004, the present value of cumulative health care cost savings for these 10 years would be $2.4 billion.

CONCLUSIONS

The use of captopril in diabetic nephropathy will provide significant savings in health care costs; in addition, it will result in savings in indirect cost, which reflects the broader societal benefit.

The health care costs of diabetic nephropathy in the United States and the United Kingdom

PROBLEM

Diabetic nephropathy (DN) is a common microvascular complication of diabetes and can result in end-stage renal disease (ESRD) necessitating long-term dialysis or kidney transplantation. The costs of these complications are relatively high. The aim of this study was to quantify and compare the rates and annual costs of DN in the USA and the UK.

METHODS

A cost of illness model was used to estimate the numbers of people with DN (microalbuminuria, overt nephropathy, and ESRD) or a previous kidney transplant at a given point in time and the numbers of new kidney transplants during a year. All costs were estimated in 2001 currencies. A sensitivity analysis assessed the robustness of the national annual cost estimates.

RESULTS

In the USA, the total annual medical costs incurred by all payers in managing DN were US dollars 1.9 billion for Type 1 diabetes (range: US dollars 1.0-2.8 billion), US dollars 15.0 billion for Type 2 diabetes (range: US dollars 7.6-22.4 billion), and US dollars 16.8 billion for all diabetes (range: US dollars 8.5-25.2 billion). In the UK, the total annual costs to the National Health Service (NHS) of managing DN were US dollars 231 million ( pound 152 million) for Type 1 diabetes (range: US dollars 190-350 million [ pound 125-230 million]), US dollars 933 million (pound 614 million) for Type 2 diabetes (range: US dollars 809 million-US dollars 1.4 billion [pound 532-927 million]), and US dollars 1.2 billion ( pound 765 million) for all diabetes (range: US dollars 999 million-US dollars 1.8 billion [pound 657 million- pound 1.2 billion]).

CONCLUSIONS

The total annual cost of DN is 13 times greater in the USA than in the UK. Controlling for the substantially higher number of people at risk, the total cost per person with DN and/or a kidney transplant is 40% higher: US dollars 3735 in the USA and US dollars 2672 (pound 1758) in the UK.

End-stage renal disease-associated managed care costs among patients with and without diabetes

OBJECTIVE

To examine the direct costs of care before and after onset of end-stage renal disease (ESRD) for patients with and without diabetes based on analyses of retrospective healthcare claims data.

RESEARCH DESIGN AND METHODS

Patients with onset of ESRD between January 1998 though June 2002 were identified based on use of dialysis, renal transplantation, or other ESRD-related services. Continuous health plan enrollment > or =12 months before and > or =1 month after ESRD onset was required. The costs calculated include both observed and adjusted estimates; the latter were calculated using generalized linear models, controlling for demographic and clinical characteristics, "onset" period, and duration of follow-up. Analyses focus on the diabetic ESRD patient and include a comparison with ESRD patients without diabetes.

RESULTS

The study included 2,020 patients with diabetes and 2,170 without diabetes; 63% of patients were >50 years of age. Average costs were relatively stable before ESRD ($1,535 to $4,357 for diabetes, $1,082 to $2,447 for no diabetes) but more than doubled in the month preceding onset ($9,152 and $8,211, respectively). Postonset, average monthly per-patient costs escalated sharply in the 1st month ($26,507 and $26,789), declined steadily through month 6, and remained flat but elevated thereafter. Adjusted annual costs per patient pre- and postonset of ESRD were significantly higher for diabetes (P <0.0001); annual costs were 69% ($38,041 vs. $22,538) and 79% ($96,014 vs. $53,653) higher pre- and postonset, respectively.

CONCLUSIONS

The economic burden of ESRD in the year after onset is substantial, particularly among patients with diabetes.

Direct all-cause health care costs associated with chronic kidney disease in patients with diabetes and hypertension: a managed care perspective

BACKGROUND

Diabetes and hypertension are the 2 major causes of endstage renal disease. The rate of chronic kidney disease (CKD) secondary to diabetes and/or hypertension is on the rise, and the related health care costs represent a significant economic burden.

OBJECTIVE

To quantify from a health system perspective the incremental direct all-cause health care costs associated with a diagnosis of CKD in patients with diabetes and/or hypertension.

METHODS

An analysis was conducted of medical claims and laboratory data with dates of service between January 1, 2000, and February 28, 2006, from a managed care database for approximately 30 million members enrolled in 35 health plans. Each patient's observation period began on the date of the first diabetes or hypertension diagnosis (index date) and ended on the earlier of the health plan disenrollment date or February 28, 2006. Inclusion criteria were continuous insurance coverage in the 6 months prior to the index date and during the observation period, age at least 18 years, and at least 2 claims less than 90 days apart with a primary or secondary diagnosis for diabetes or hypertension. Exclusion criteria were cancer, lupus, or organ transplantation or chemotherapy at any time during the observation period. CKD was defined as at least 1 claim with a primary or secondary diagnosis for CKD and at least 2 glomerular filtration rate values of below 60 milliliters per minute per 1.73 square meters of body surface area (60 mL/min/1.73 m(2)) at any time during the observation period. Bivariate and Tobit regression analyses were conducted to compare patients who developed CKD versus those who did not for annualized (per patient per month [PPPM] multiplied by 12) direct, all-cause, health care costs, defined as standardized net provider payments after subtraction of member cost-share. These costs consisted of outpatient services, inpatient services, and pharmacy claims. A subset analysis of the post-versus pre- CKD medical costs was also conducted for cohorts of patients with at least 60 days of observation before and after the development of CKD; that analysis measured both all-cause costs and costs for services directly related to CKD treatment (i.e., claims with a primary or secondary diagnosis of CKD or claims for dialysis services).

RESULTS

11,531 patients with diabetes, 74,759 patients with hypertension, and 4,779 patients with both conditions were identified, of whom 123 (1.1%), 1,137 (1.5%), and 712 (14.9%), respectively, developed CKD during the observation period. The CKD group was older than the no-CKD group in each cohort (mean ages for CKD vs. no-CKD were, respectively, diabetes only cohort: 60.7 vs. 49.9 years, P < 0.001; hypertension only cohort: 63.6 vs. 53.6 years, P < 0.001; diabetes and hypertension cohort: 63.4 vs. 61.8 years, P < 0.001). CKD was associated with significantly higher total direct all-cause health care costs, with unadjusted annualized per patient mean [median] cost differences of $11,814 [$6,895], $8,412 [$4,115], and $10,625 [$7,203], respectively (diabetes: $18,444 [$11,025] vs. $6,631 [$4,131], P < 0.001; hypertension: $14,638 [$7,817] vs. $6,226 [$3,703], P < 0.001; diabetes and hypertension: $21,452 [$13,840] vs. $10,827 [$6,637], P < 0.001). The largest driver of the all-cause mean cost difference associated with CKD for each cohort was hospitalization cost (diabetes: $6,410, P < 0.001; hypertension: $5,498, P < 0.001; diabetes and hypertension: $6,467, P < 0.001). Among patients developing CKD, all-cause mean [median] annualized costs increased significantly following CKD onset (increases for patients with diabetes: $8,829 [$4,899], P = 0.026; hypertension: $4,175 [$2,741], P = 0.004; diabetes and hypertension: $9,397 [$7,240], P < 0.001). In the post-CKD period, costs directly related to treatment of CKD accounted for 9%--19% of all-cause medical service costs--9.2% for patients with diabetes, 11.6% for patients with hypertension, and 18.8% for patients with both diabetes and hypertension.

CONCLUSION

CKD was associated with significantly higher all-cause health care costs in managed care patients with diabetes and/or hypertension.

Losartan reduces the costs associated with diabetic end-stage renal disease: the RENAAL study economic evaluation

OBJECTIVE

To evaluate the within-trial effect of losartan and conventional antihypertensive therapy (CT) compared with placebo and CT on the economic cost associated with end-stage renal disease (ESRD).

RESEARCH DESIGN AND METHODS

The Reduction of End Points in Type 2 Diabetes With the Angiotensin II Antagonist Losartan (RENAAL) study was a multinational double-blind randomized placebo-controlled clinical trial designed to evaluate the renal protective effects of losartan on a background of CT (excluding ACE inhibitors and angiotensin II receptor agonists [AIIAs]) in patients with type 2 diabetes and nephropathy. The primary composite end point was doubling of serum creatinine, ESRD, or death. Data on the duration of ESRD were used to estimate the economic benefits of slowing the progression of nephropathy. The cost associated with ESRD was estimated by combining the days each patient experienced ESRD with the cost of ESRD over time. The cost of ESRD for individuals with diabetes was estimated using data from the U.S. Renal Data System. Total cost was estimated as the sum of the cost associated with ESRD and the cost of study therapy. RESULTS-We estimated that losartan and CT compared with placebo and CT reduced the number of days with ESRD by 33.6 per patient over 3.5 years (P = 0.004, 95% CI 10.9-56.3). This reduction in ESRD days resulted in a decrease in cost associated with ESRD of 5144 US dollars per patient (P = 0.003, 95% CI 1701 to 8587 US dollars). After accounting for the cost of losartan, the reduction in ESRD days resulted in a net savings of 3522 US dollars per patient over 3.5 years (P = 0.041, 143 to 6900 US dollars).

CONCLUSIONS

Treatment with losartan in patients with type 2 diabetes and nephropathy not only reduced the incidence of ESRD, but also resulted in substantial cost savings.

Dialysis Care and Dialysis Funding in Asia

Asia is the largest and most populated continent in the world, with a high burden of kidney failure. In this Policy Forum article, we explore dialysis care and dialysis funding in 17 countries in Asia, describing conditions in both developed and developing nations across the region. In 13 of the 17 countries surveyed, diabetes is the most common cause of kidney failure. Due to great variation in gross domestic product per capita across Asian countries, disparities in the provision of kidney replacement therapy (KRT) exist both within and between countries. A number of Asian nations have satisfactory access to KRT and have comprehensive KRT registries to help inform practices, but some do not, particularly among low- and low-to-middle-income countries. Given these differences, we describe the economic status, burden of kidney failure, and cost of KRT across the different modalities to both governments and patients and how changes in health policy over time affect outcomes. Emerging trends suggest that more affluent nations and those with universal health care or access to insurance have much higher prevalent dialysis and transplantation rates, while in less affluent nations, dialysis access may be limited and when available, provided less frequently than optimal. These trends are also reflected by an association between nephrologist prevalence and individual nations' incomes and a disparity in the number of nephrologists per million population and per thousand KRT patients.

The impact of patient preferences on the cost-effectiveness of intensive glucose control in older patients with new-onset diabetes

OBJECTIVE

Cost-effectiveness analyses have reported that intensive glucose control is not cost-effective in older patients with new-onset diabetes. However, these analyses have had limited data on patient preferences concerning diabetic health states. We examined how the cost- effectiveness of intensive glucose control changes with the incorporation of patient preferences.

RESEARCH DESIGN AND METHODS

We collected health state preferences/utilities from 519 older diabetic patients. We incorporated these utilities into an established cost-effectiveness model of intensive glucose control and compared incremental cost-effectiveness analyses ratios (ICERs) (cost divided by quality-adjusted life-year [QALY]) when using the original and patient-derived utilities for complications and treatments.

RESULTS

The mean utilities were approximately 0.40 for major complications, 0.76 (95% CI 0.74-0.78) for conventional glucose control, 0.77 (0.75-0.80) for intensive therapy with oral medications, and 0.64 (0.61-0.67) for intensive therapy with insulin. Incorporating our patient-derived complication utilities alone improved ICERs for intensive glucose control (e.g., patients aged 60-65 years at diagnosis, 136,000 dollars/QALY-->78,000 dollars/QALY), but intensive therapy was still not cost-effective at older ages. When patient-derived treatment utilities were also incorporated, the cost-effectiveness of intensive treatment depended on the method of glucose control. Intensive control with insulin generated fewer QALYs than conventional control. However, intensive control with oral medications was beneficial on average at all ages and had an ICER < or =100,000 dollars to age 70.

CONCLUSIONS

The cost-effectiveness of intensive glucose control in older patients with new-onset diabetes is highly sensitive to assumptions regarding quality of life with treatments. Cost-effectiveness analyses of diabetes care should consider the sensitivity of results to alternative utility assumptions.

The cost of insulin-dependent diabetes mellitus (IDDM) in England and Wales

This study estimates the direct health and social care costs of insulin-dependent diabetes mellitus (IDDM) in England and Wales in 1992 to be 96 million pounds, or 1021 pounds per person in a population with IDDM estimated at 94,000 individuals. These costs include insulin maintenance, hospitalization, GP and out-patient consultations, renal replacement therapy, and payments to informal carers. Expenditure is concentrated on younger age groups, with one-third of the total expended on those aged 0-24. Around one-half of the total costs can be directly attributed to IDDM, with the remainder associated with a range of complications of the disease. The single largest area of service expenditure is renal replacement therapy. The cost estimates are most sensitive to incidence rates of IDDM, numbers on dialysis and average duration of dialysis. A further 113 million pounds may be lost each year due to premature deaths resulting in lost productive contributions to the economy. The direct and indirect costs of IDDM are therefore significant. The cost of illness framework presented here should facilitate the economic evaluation of new and existing treatment regimens, which may improve value for money by reducing costs and/or increasing the quality or quantity of life for people with IDDM.

Cost-effectiveness of screening and early treatment of nephropathy in patients with insulin-dependent diabetes mellitus

Studies have demonstrated that "antihypertensive" treatment with angiotensin-converting enzyme inhibitors (ACEI) may retard the progress of nephropathy in patients with insulin-dependent diabetes mellitus. To obtain an indication of the potential effect of ACEI treatment and as a guide to future research, the effects of screening and early ACEI treatment programs were estimated using cost-effectiveness models. The preliminary analysis suggests that the early treatment of insulin-dependent diabetes mellitus patients with ACEI is likely to be a very cost-effective use of health care resources. The cost-effectiveness ratio for screening and treatment at the stage of microalbuminuria ($7,900 to $16,500 per year of life saved) compares favorably with those of other medical life-saving interventions. Less-aggressive programs (screening followed by treatment at the stage of proteinuria) would improve life expectancy to a lesser extent but could save net health care costs as well as years of life. Although more exact and comprehensive cost-effectiveness analysis must await clinical trials, these illustrative results demonstrate the range of cost-effectiveness that can be expected from these programs and identify data needed for more decisive policy conclusions.

Microalbuminuria: prognostic and therapeutic implications in diabetes mellitus

Thirty years following the development of the first radioimmunoassay for albumin, microalbuminuria is widely acknowledged as an important predictor of overt nephropathy in patients with Type 1 diabetes and of cardiovascular mortality in Type 2 diabetes. In addition, there is accumulating evidence to suggest that diabetic patients with microalbuminuria may have more advanced retinopathy, higher blood pressure, and worse dyslipidaemia than patients with normal albumin excretion rates. Recent studies have focused on the role of intervention, principally with antihypertensive therapy and intensive glycaemic control, in reducing microalbuminuria. While successful in reducing urinary albumin excretion it remains to be established whether such therapies will be translated into a reduction in renal failure and decreased cardiovascular morbidity and mortality.

Economic outcomes associated with microvascular complications of type 2 diabetes mellitus: results from a US claims data analysis

BACKGROUND

Patients with diabetes mellitus have been shown to be at high risk for both macrovascular and microvascular complications (MVC). Recent studies have focused on MVC and their effect on the healthcare system, but limited published data exist on long-term costs associated with MVC in patients with type 2 diabetes mellitus (T2DM).

OBJECTIVE

The objective of this study was to compare resource utilization and medical costs over a 12-month period among patients diagnosed with T2DM with versus without MVC in a managed-care population.

METHODS

Patients aged >/=18 years, diagnosed with T2DM between 1 January 2003 and 31 December 2004 were identified in an administrative claims database of approximately 55 million beneficiaries in private and public health plans. The date of the first T2DM diagnosis during this period was the 'index date' for each patient. All patients had to have a minimum of 12 months of continuous enrolment both prior to and following the index date. MVC was identified during the 12 months prior to the first T2DM diagnosis and these patients were matched (1 : 2) by age, sex and ten co-morbid conditions to those with no evidence of MVC during the entire study period.

RESULTS

Among the 15 326 MVC patients included in the study, 61% had a history of peripheral neuropathy, 28% diabetic retinopathy and 19% nephropathy. Compared with 30 652 patients without MVC, the MVC patients were more likely to use oral antidiabetics and insulin and had a higher co-morbidity score. Over 12 months, patients with MVC had more (mean 0.3 vs 0.2; p < 0.001) and longer (mean length of stay 1.79 days vs 0.85 days; p < 0.001) hospital stays; physician office visits (19.7 vs 13.7; p < 0.001); and prescriptions for oral antidiabetic (6.3 vs 5.6 scripts; p < 0.001) and insulin (0.7 vs 0.2 scripts; p < 0.001) use. Average total costs per patient over 12 months were $US14 414 with MVC versus $US8669 without MVC (p < 0.001).

CONCLUSIONS

This study indicates that in patients with T2DM, MVC is associated with significant consumption of healthcare resources. Mean total costs with MVC were almost double those of patients without MVC over a 12-month period.

Treatment strategies for insulin-dependent diabetics with ESRD: a cost-effectiveness decision analysis model

Clinical decision analysis has become an important tool for evaluating specific clinical scenarios and exploring public health policy issues. A decision analysis model that incorporates patient preferences regarding various outcomes, as well as cost, may be particularly informative in patients with type I diabetes and end-stage renal disease (ESRD). Such a model that includes pancreas transplantation as a treatment choice has not been performed and is presented in this study. The decision tree consisted of a choice between four possible treatment strategies: dialysis, kidney-alone transplant from a cadaver (KA-CAD) or living donor (KA-LD), and simultaneous pancreas-kidney (SPK) transplant. The analysis was based on a 5-year model, and the measures of outcome used in the model were cost and cost adjusted for quality of life. The measure of preference for quality of life was obtained using the "Standard Reference Gamble" method in 17 SPK transplant recipients who underwent transplantation between January, 1992 and June, 1996 at our center. The measures for various outcome states (mean +/- 1 SD) were dialysis-free/insulin-free = 1, dialysis-free/insulin-dependent = 0.6 (0.4 to 0.8), dialysis-dependent/insulin-free = 0.5 (0.36 to 0.64), dialysis-dependent/insulin-dependent = 0.4 (0.21 to 0.59), and death = 0. The expected 5-year costs for each of the treatment strategies in the model were dialysis, $216,068; KA-CAD transplant, $214,678; KA-LD transplant, $210,872; and SPK transplant, $241,207. The expected cost per quality-adjusted year for each of the treatment strategies in the model were dialysis, $317,746; KA-CAD transplant, $156,042; KA-LD transplant, $123,923; and SPK transplant, $102,422. SPK transplantation remained the optimal strategy after varying survival probabilities, costs, and utilities over plausible ranges by means of one-way sensitivity analysis. In conclusion, according to the 5-year cost-utility model presented in this study, SPK transplantation is the most cost-effective treatment strategy for a patient with type I diabetes and ESRD. From a policy standpoint, looking at the cost alone of pancreas transplantation is deceiving. In these patients, who may view various outcome states differently, it would be important to take into account cost adjusted for quality of life when evaluating this procedure.