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William H Herman

Publications and source records attributed to William H Herman.

At least 37 records · Page 2Linked to original sources

The cost-effectiveness of lifestyle modification or metformin in preventing type 2 diabetes in adults with impaired glucose tolerance.

BACKGROUND: The Diabetes Prevention Program (DPP) demonstrated that interventions can delay or prevent the development of type 2 diabetes. OBJECTIVE: To estimate the lifetime cost-utility of the DPP interventions. DESIGN: Markov simulation model to estimate progression of disease, costs, and quality of life. DATA SOURCES: The DPP and published reports. TARGET POPULATION: Members of the DPP cohort 25 years of age or older with impaired glucose tolerance. TIME HORIZON: Lifetime. PERSPECTIVES: Health system and societal. INTERVENTIONS: Intensive lifestyle, metformin, and placebo interventions as implemented in the DPP. OUTCOME MEASURES: Cumulative incidence of diabetes, microvascular and neuropathic complications, cardiovascular complications, survival, direct medical and direct nonmedical costs, quality-adjusted life-years (QALYs), and cost per QALY. RESULTS OF BASE-CASE ANALYSIS: Compared with the placebo intervention, the lifestyle and metformin interventions were estimated to delay the development of type 2 diabetes by 11 and 3 years, respectively, and to reduce the absolute incidence of diabetes by 20% and 8%, respectively. The cumulative incidence of microvascular, neuropathic, and cardiovascular complications were reduced and survival was improved by 0.5 and 0.2 years. Compared with the placebo intervention, the cost per QALY was approximately 1100 dollars for the lifestyle intervention and $31 300 for the metformin intervention. From a societal perspective, the interventions cost approximately 8800 dollars and 29,900 dollars per QALY, respectively. From both perspectives, the lifestyle intervention dominated the metformin intervention. RESULTS OF SENSITIVITY ANALYSIS: Cost-effectiveness improved when the interventions were implemented as they might be in routine clinical practice. The lifestyle intervention was cost-effective in all age groups. The metformin intervention did not represent good use of resources for persons older than 65 years of age. LIMITATIONS: Simulation results depend on the accuracy of the underlying assumptions, including participant adherence. CONCLUSIONS: Health policy should promote diabetes prevention in high-risk individuals.

Adult↗

Preconception care in managed care: the translating research into action for diabetes study.

OBJECTIVES: This study was undertaken to examine the rates of preconception counseling in managed care for women with diabetes and associated patient and physician characteristics. STUDY DESIGN: Participants included women aged 18 to 45 years enrolled in a study of diabetes care in managed care. Women were asked if they recalled discussions regarding glucose control before conception (n = 236) and use of family planning until glucose control was achieved (n = 227). Hierarchical logistic regression models accounted for patient and physician characteristics. RESULTS: Fifty-two percent of women recalled being counseled about glucose control and 37% recalled family planning advice. In adjusted models, patient age (years) (odds ratio [OR] 0.91, 95% CI 0.86-0.96) and body mass index (BMI) (kg/m2) (OR 0.96, 95% CI 0.93-0.99) remained significant predictors of glucose control counseling. Similarly, patient age (years) (OR 0.94, 95% CI 0.89-0.99) and BMI (kg/m2) (0.96, 95% CI 0.93-0.99) remained significant predictors of family planning counseling. CONCLUSIONS: Preconception counseling rates for diabetic women are low and associated with younger age and lower BMI.

Adolescent↗

Glycated hemoglobin assessment in clinical practice: comparison of the A1cNow point-of-care device with central laboratory testing (GOAL A1C Study).

BACKGROUND: The Glycemic Optimization with Algorithms and Labs At Po1nt of Care (GOAL A1C) Study assessed the effect of titration monitoring strategies and methods of A1C testing on glycemic control in patients with type 2 diabetes failing oral therapy and beginning basal insulin glargine. The availability of both point-of-care (POC) and central laboratory A1C values provided an opportunity to evaluate correlation and statistical agreement between these methods of testing. This analysis forms the basis of the current report. METHODS: This is a 24-week, randomized, four-arm, open-label study conducted in 7,758 subjects enrolled at 2,130 sites. At baseline, patients had A1C measurements both by POC testing using the A1cNow device (Metrika, Inc., Sunnyvale, CA), which applies an immunoassay method, and by central laboratory analysis using ion exchange high-performance liquid chromatography. These measures were compared statistically. RESULTS: An r value of 0.72 was calculated for POC and laboratory A1C assessments. Although the mean POC A1C values were in agreement with the central laboratory values, there was a large range in individual POC A1C values. CONCLUSIONS: POC testing of A1C in predominantly primary care settings using the A1cNow device was correlated with central laboratory results. The correlation was less than expected based on each method's reproducibility data. Although there was agreement between the average POC A1C values and the corresponding central laboratory values, the dispersion of individual POC A1C values was large. Thus, we conclude that these two methods of A1C testing should not be used interchangeably.

Aged↗

Does diabetes care compete with the provision of women's preventive care services?

OBJECTIVE: Care for chronic diseases may compete with preventive health care. To test this hypothesis, we examined the association between diabetes-related processes of care and preventive care in women. RESEARCH DESIGN AND METHODS: Using data from a prospective cohort study of diabetes care in managed care settings, we reviewed the care 540 diabetic women received from 355 primary care providers within 14 provider groups from one health plan. Of the 540 women, 278 were eligible to receive mammograms and 314 were eligible to receive Pap smears. Mammography performance was measured as at least one mammogram over a 2-year period and Pap performance was measured as at least one Pap smear over a 3-year period. To assess the association between diabetes-related processes of care and preventive services, we used hierarchical logistic regression models, accounted for clustering within provider groups, and adjusted for patient age, race, income and education level, diabetes treatment and duration, and health status, as well as physician age, sex, years of practice, and specialty. Diabetes-related processes of care were defined as dilated retinal examinations, urine microalbumin/protein testing, foot examinations, lipid and HbA(1c) testing, recommendations to take aspirin, and influenza vaccinations received over a 1-year period. RESULTS: In this cohort, 73% of eligible women received mammograms and 56% received Pap smears. After adjustment of models, better diabetes-related processes of care, better health status, and non-Medicaid insurance were associated with mammography performance. Better diabetes-related processes of care, younger patient age, and any visit to a gynecologist were associated with Pap performance. CONCLUSIONS: Better processes of diabetes care were associated with better women's preventive health care. Diabetes management did not compete with sex-specific screening.

Aged↗

A computer simulation model of diabetes progression, quality of life, and cost.

OBJECTIVE: To develop and validate a comprehensive computer simulation model to assess the impact of screening, prevention, and treatment strategies on type 2 diabetes and its complications, comorbidities, quality of life, and cost. RESEARCH DESIGN AND METHODS: The incidence of type 2 diabetes and its complications and comorbidities were derived from population-based epidemiologic studies and randomized, controlled clinical trials. Health utility scores were derived for patients with type 2 diabetes using the Quality of Well Being-Self-Administered. Direct medical costs were derived for managed care patients with type 2 diabetes using paid insurance claims. Monte Carlo techniques were used to implement a semi-Markov model. Performance of the model was assessed using baseline and 4- and 10-year follow-up data from the older-onset diabetic population studied in the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR). RESULTS: Applying the model to the baseline WESDR population with type 2 diabetes, we predicted mortality to be 51% at 10 years. The prevalences of stroke and myocardial infarction were predicted to be 18 and 19% at 10 years. The prevalences of nonproliferative diabetic retinopathy, proliferative retinopathy, and macular edema were predicted to be 45, 16, and 18%, respectively; the prevalences of microalbuminuria, proteinuria, and end-stage renal disease were predicted to be 19, 39, and 3%, respectively; and the prevalences of clinical neuropathy and amputation were predicted to be 52 and 5%, respectively, at 10 years. Over 10 years, average undiscounted total direct medical costs were estimated to be USD $53,000 per person. Among survivors, the average utility score was estimated to be 0.56 at 10 years. CONCLUSIONS: Our computer simulation model accurately predicted survival and the cardiovascular, microvascular, and neuropathic complications observed in the WESDR cohort with type 2 diabetes over 10 years. The model can be used to predict the progression of diabetes and its complications, comorbidities, quality of life, and cost and to assess the relative effectiveness, cost-effectiveness, and cost-utility of alternative strategies for the prevention and treatment of type 2 diabetes.

Computer Simulation↗

The efficacy and cost of alternative strategies for systematic screening for type 2 diabetes in the U.S. population 45-74 years of age.

OBJECTIVE: To simulate the outcomes of alternative strategies for screening the U.S. population 45-74 years of age for type 2 diabetes. RESEARCH DESIGN AND METHODS: We simulated screening with random plasma glucose (RPG) and cut points of 100, 130, and 160 mg/dl and a multivariate equation including RPG and other variables. Over 15 years, we simulated screening at intervals of 1, 3, and 5 years. All positive screening tests were followed by a diagnostic fasting plasma glucose or an oral glucose tolerance test. Outcomes include the numbers of false-negative, true-positive, and false-positive screening tests and the direct and indirect costs. RESULTS: At year 15, screening every 3 years with an RPG cut point of 100 mg/dl left 0.2 million false negatives, an RPG of 130 mg/dl or the equation left 1.3 million false negatives, and an RPG of 160 mg/dl left 2.8 million false negatives. Over 15 years, the absolute difference between the most sensitive and most specific screening strategy was 4.5 million true positives and 476 million false-positives. Strategies using RPG cut points of 130 mg/dl or the multivariate equation every 3 years identified 17.3 million true positives; however, the equation identified fewer false-positives. The total cost of the most sensitive screening strategy was $42.7 billion and that of the most specific strategy was $6.9 billion. CONCLUSIONS: Screening for type 2 diabetes every 3 years with an RPG cut point of 130 mg/dl or the multivariate equation provides good yield and minimizes false-positive screening tests and costs.

Aged↗

A clinical trial of continuous subcutaneous insulin infusion versus multiple daily injections in older adults with type 2 diabetes.

OBJECTIVE: To compare the efficacy and safety of continuous subcutaneous insulin infusion (CSII) and multiple daily injection (MDI) in older adults with insulin-treated type 2 diabetes and to assess treatment satisfaction and quality of life. RESEARCH DESIGN AND METHODS: Adults (n = 107) > or =60 years of age (mean age 66 years) with insulin-treated type 2 diabetes (mean duration 16 years, BMI 32 kg/m(2), and HbA(1C) [A1C] 8.2%) were randomized to CSII (using insulin lispro) or MDI (using insulin lispro and insulin glargine) in a two-center, 12-month, prospective, randomized, controlled clinical trial. Efficacy was assessed with A1C, safety by frequency of hypoglycemia, and treatment satisfaction and quality of life with the Diabetes Quality of Life Clinical Trial Questionnaire and the 36-item short-form health survey, version 2. RESULTS: Forty-eight CSII subjects (91%) and 50 MDI subjects (93%) completed the study. Mean A1C fell by 1.7 +/- 1.0% in the CSII group to 6.6% and by 1.6 +/- 1.2% in the MDI group to 6.4%. The difference in A1C between treatment groups was not statistically significant (P = 0.20). Eighty-one percent of CSII subjects and 90% of MDI subjects experienced at least one episode of minor (self-treated) hypoglycemia (P = 0.17), and three CSII and six MDI subjects experienced severe hypoglycemia (P = 0.49). Rates of severe hypoglycemia were similarly low in the two groups (CSII 0.08 and MDI 0.23 events per person-year, P = 0.61). Weight gain did not differ between groups (P = 0.70). Treatment satisfaction improved significantly with both CSII and MDI (P < 0.0001), and the difference between groups was not statistically significant (P = 0.58). CONCLUSIONS: In older subjects with insulin-treated type 2 diabetes, both CSII and MDI achieved excellent glycemic control with good safety and patient satisfaction.

Diabetes Mellitus, Type 2↗

Is physician gender associated with the quality of diabetes care?

OBJECTIVE: This study examines the association between physician gender and diabetes quality of care. RESEARCH DESIGN AND METHODS: We examined the association between the gender of primary care physicians (n = 1,686) and the quality of diabetes care they provided to their patients participating in the Translating Research Into Action for Diabetes (TRIAD) study. Main outcome measures were diabetes processes of care including receipt of dilated retinal exams, urine microalbumin/protein testing, foot exams, lipid and HbA(1c) (A1C) testing, recommendation to take aspirin, and influenza vaccination over 1 year. Intermediate outcomes included blood pressure, A1C, LDL levels, and patient satisfaction. Hierarchical regression models accounted for clustering within provider groups and health plans and adjusted for patient age, gender, race, income, education, diabetes treatment and duration, and health status, along with physician age, years of practice, and specialty. RESULTS: Compared with male physicians (n = 1,213), female physicians (n = 473) were younger, had more recently completed training, and were more often internists. Patients of female physicians (n = 4,585) were more often women and younger than patients of male physicians (n = 1,783). In adjusted analyses, patients of female physicians were slightly more likely to receive lipid measurements (predicted probability 1.09 [95% CI 1.02-1.15]) and A1C measurements (1.02 [1.00-1.05]) and were slightly more likely to have an LDL <130 mg/dl (1.05 [1.00-1.10]). CONCLUSIONS: Patients of female physicians received similar quality of care compared with patients of male physicians.

Adult↗

Reduction in use of healthcare services with combination sulfonylurea and rosiglitazone: findings from the Rosiglitazone Early vs SULfonylurea Titration (RESULT) study.

OBJECTIVE: To assess and compare healthcare utilization and costs over a 2-year period in older patients (> or = 60 years) with type 2 diabetes receiving combination therapy with rosiglitazone plus a sulfonylurea (glipizide) or progressive up-titration of glipizide monotherapy. STUDY DESIGN: Two-year, randomized, double-blind, parallel-group clinical trial. PATIENTS AND METHODS: Older type 2 diabetic patients initially receiving submaximal doses of a sulfonylurea were randomized to receive rosiglitazone plus glipizide (n = 115) or up-titrated glipizide monotherapy (n = 110). Information on patient self-reported healthcare utilization (hospitalizations, emergency department [ED] visits, physician office visits) was collected prospectively for the duration of the trial. National average healthcare costs per unit were applied to calculate direct medical costs. RESULTS: Demographic characteristics of the 2 groups were similar. At the study's end, glycemic values were better in the rosiglitazone-plus-glipizide group. Compared with the glipizide group, patients receiving rosiglitazone plus glipizide had significantly fewer ED visits (P = .0006) and hospitalizations (P = .0263). Although the glipizide group had more unscheduled physician office visits, the difference was not statistically significant. Estimated treatment costs per patient per month were significantly lower for the rosiglitazone-plus-glipizide group than for the glipizide group (480 dollars vs 645 dollars; P < .05). CONCLUSION: Addition of rosiglitazone to sulfonylurea therapy was associated with decreased use of medical resources, in particular hospitalizations and ED visits, compared with progressive sulfonylurea up-titration. Although causality could not be established, this therapeutic approach could improve clinical outcomes in patients with type 2 diabetes and reduce healthcare utilization and costs.

Adult↗

Diabetes care quality in the Veterans Affairs Health Care System and commercial managed care: the TRIAD study.

BACKGROUND: No studies have compared care in the Department of Veterans Affairs (VA) with that delivered in commercial managed care organizations, nor have studies focused in depth on care comparisons for chronic, outpatient conditions. OBJECTIVE: To compare the quality of diabetes care between patients in the VA system and those enrolled in commercial managed care organizations by using equivalent sampling and measurement methods. DESIGN: Cross-sectional patient survey with retrospective review of medical records. SETTING: 5 VA medical centers and 8 commercial managed care organizations in 5 matched geographic regions. PARTICIPANTS: 8205 diabetic patients: 1285 in the VA system and 6920 in commercial managed care. MEASUREMENTS: We compared scores on identically specified quality measures for 7 diabetes care processes and 3 diabetes intermediate outcomes and on 4 dimensions of satisfaction. Scores were expressed as the percentage of patients receiving indicated care and were adjusted for patients' demographic and health characteristics. RESULTS: Patients in the VA system had better scores than patients in commercial managed care on all process measures (for example, 93% vs. 83% for annual hemoglobin A1c; P = 0.006; 91% vs. 75% for annual eye examination; P < 0.001). Blood pressure control was poor in both groups (52% to 53% of persons had blood pressure < 140/90 mm Hg), but patients in the VA system had better control of low-density lipoprotein cholesterol and hemoglobin A1c (for example, 86% vs. 72% for low-density lipoprotein cholesterol level < 3.37 mmol/L [<130 mg/dL]; P = 0.002). Satisfaction was similar in the 2 groups. LIMITATIONS: Our results may not be generalizable to all regions or health plans, and some of the differences in performance could reflect differences in documentation. CONCLUSIONS: Diabetes processes of care and 2 of 3 intermediate outcomes were better for patients in the VA system than for patients in commercial managed care. However, both VA and commercial managed care had room for improvement, especially for blood pressure control.

Aged↗

Cost effectiveness of ACE inhibitor treatment for patients with type 1 diabetes mellitus.

OBJECTIVE: Current guidelines recommend treating patients with type 1 diabetes mellitus with ACE inhibitors after the onset of microalbuminuria. Recent clinical trials have shown ACE inhibitors can affect the development of nephropathy when initiated prior to the onset of microalbuminuria. Our objective is to examine the cost effectiveness of treating adults aged over 20 years with an ACE inhibitor (captopril) immediately following diagnosis of type 1 diabetes versus treating them after the onset of microalbuminuria. DESIGN: Using a semi-Markov model, we calculated four main outcome measures: lifetime direct medical costs (discounted), QALYs, cumulative incidence of end-stage renal disease (ESRD), and number of days of ESRD over a lifetime. Medical costs are in 1999 US dollars. SETTING: All analyses were from the viewpoint of a single US payer responsible for all direct medical costs, including screening for microalbuminuria, ACE inhibitor treatment (captopril), management of major diabetic complications, and routine annual medical costs not specific to diabetes. METHODS: We applied the model to a hypothetical cohort of 10,000 persons newly diagnosed with type 1 diabetes. Distribution of sex and race/ethnicity within the cohort is representative of the general US population. RESULTS: We estimated that the incremental cost of early use of captopril for the average adult with type 1 diabetes is USD 27,143 per QALY. This level varies considerably with age and glycaemic level. When the age at onset of diabetes is 20 years and glycosylated haemoglobin (HbA(1c)) level is 9%, the cost-effectiveness ratio is USD 13,814 per QALY. When the age at onset is 25 years and HbA(1c) level is 7%, the cost-effectiveness ratio is USD 39,530 per QALY. CONCLUSION: This model, with its underlying assumptions and data, suggests that early treatment with captopril provides modest benefit at reasonable cost effectiveness, from the US single-payer perspective, in the prevention of ESRD compared with delaying treatment until diagnosis of microalbuminuria. Early treatment with other ACE inhibitors will provide similar cost effectiveness if they have equivalent efficacy, compliance and price per dose. Treatment may be considered among patients at age 20 years with new onset of type 1 diabetes. This conclusion is sensitive to the extent that ACE inhibitors delay onset of microalbuminuria. Other factors such as the patient's age and glycaemic level must be considered when deciding to initiate early treatment.

Adult↗

The prevalence of the metabolic syndrome among arab americans.

OBJECTIVE: To estimate the prevalence of the metabolic syndrome in Arab Americans by age, sex, and BMI and to examine the association between insulin resistance and each of the components of the metabolic syndrome. RESEARCH DESIGN AND METHODS: We studied a representative, cross-sectional, population-based sample of 542 Arab Americans aged 20-75 years. The metabolic syndrome was defined by Adult Treatment Panel III (ATP III) and World Health Organization (WHO) diagnostic criteria. Insulin resistance was estimated by homeostasis model assessment (HOMA-IR). RESULTS: The age-adjusted prevalence of the metabolic syndrome was 23% (95% CI 19-26%) by the ATP III definition and 28% (24-32%) by the WHO definition. Although the prevalence increased significantly with age and BMI in both sexes by both definitions, differences in estimates were noted. With ATP III, the age-specific rates were similar for men and women aged 20-49 years but were significantly higher for women aged >/=50 years. With WHO, rates were higher for men than women aged 20-49 years and similar for those aged >/=50 years. The most common component of the metabolic syndrome in men and women was low HDL cholesterol with the ATP III and the presence of glucose intolerance and HOMA-IR with the WHO. Strong associations between HOMA-IR and individual components of the metabolic syndrome were observed. After fitting a model with HOMA-IR as the outcome, waist circumference, triglyceride level, and fasting plasma glucose level were significantly associated with HOMA-IR. CONCLUSIONS: The metabolic syndrome is common among Arab Americans and is related to modifiable risk factors.

Adult↗