A relational study of gestational diabetes and type 2 diabetes

Objectives: The purposes of this study were to investigate the factors impacting the women with gestational diabetes mellitus (GDM) developing type 2 diabetes and its incidence density and to compare the differences between developing type 2 diabetes and non-developing type 2 diabetes in risk factors of coronary heart disease. Method: Based on a non-concurrent cohort study design, we got a total of 558 women with GDM and delivered to a medical center in Taipei from 1998 to 2002. We invited them to participate in the activity of "Come Back Home for Women with GDM" through telephone and mailing from May to June of 2003. Participants were asked to complete the questionnaire and finish the blood test when they came back. The StatXact 4.0 was used to analyze the incidence density of type 2 diabetes. In addition, we presented the descriptive analysis, t-test, K-W test, and Multivariate Logistic Regression analysis using SPSS 11.0. Results: 152 GDM women had been followed, 10 of whom developed diabetes, the other 5 women had been diagnosed with diabetes before this research, so that the diabetes incidence came up to 9.6%. The incidence density of diabetes during the years from 1998 to 2002 was 2.5%c person year, and the predicting factors of developing type 2 diabetes were "pre-pregnant body mass index" and "the plasma glucose value of 100g oral glucose tolerance test (OGTT) in the first hour during pregnancy". There was a significant association between developing type 2 diabetes and non-developing type 2 diabetes in risk factors of coronary heart disease, such as 75g OGTT 2-hour insulin and blood sugar, HbA₁c, triglyceride, actual body mass index, waist circumstance, waist buttock ratio, body fat and systolic pressure. Conclusion: The findings reveal that the incidence density of type 2 diabetes and its predictors of GDM women are similar with the findings from abroad. Developing type 2 diabetes women with GDM have higher risk factors of coronary heart disease than other non-GDM women.