Efficacy and cost of postpartum screening strategies for diabetes among women with histories of gestational diabetes mellitus

OBJECTIVE - To compare the cost and time to diagnosis associated with several screening strategies for diabetes in women with histories of gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS - We simulated screening for diabetes with fasting plasma glucose (FPG), a 2-h oral glucose tolerance test (OGTT), and A1C annually, every 2 years, and every 3 years over a period of 12 years. We assumed that women had negative screening tests 6 weeks after delivery, progressed to diabetes at 8% per year, and that each positive FPG and A1C was followed by a confirmatory FPG. For each strategy, we calculated the cost per case detected, cost per woman screened, the percent of cases detected, and the time elapsed with undiagnosed diabetes. In sensitivity analyses, we considered the inclusion of indirect costs, the impact of imperfect adherence to screening strategies, exclusion of confirmatory tests, and lower rates of progression to diabetes. RESULTS - When annual, biannual, or every 3-year screening strategies were utilized, OGTTs resulted in lower costs per case detected than FPG or A1C. Testing every 3 years resulted in lower costs per case detected compared with more frequent testing. These patterns persisted in sensitivity analyses, except that FPG resulted in lower cost per case detected than OGTT, assuming annual screening and inclusion of indirect costs or assuming annual screening without a confirmatory FPG. CONCLUSIONS - Screening every 3 years with OGTTs results in the lowest cost per case of detected diabetes.