1412-P: Racial Differences of Incident Diabetes Postpartum in Women with a History of Gestational Diabetes

The aim of the present study was to investigate the race-specific association between a history of GDM and incidence of type 2 diabetes and evaluate how the risk changed over different years after delivery. We performed two large cohorts - the Coronary Artery Risk Development in Young Adults (CARDIA) cohort with African Americans and whites in the U.S. (188 GDM and 1625 non-GDM women), and the Tianjin GDM Observational Study with Chinese in China (1263 GDM and 705 non-GDM women). The multivariate cox regression model was used to assess the risk of incident diabetes postpartum between women with and without GDM. During a mean follow-up of 13.9 years, 419 women developed type 2 diabetes. After adjustment for multiple confounding factors, Chinese women with GDM had a higher risk of incident diabetes within 5 years postpartum than African Americans with GDM compared with Chinese and African Americans without GDM (Hazard ratio 71.5 in Chinese vs. 11.0 in African Americans). When the risk of incident diabetes was analyzed within 10 years, white women with GDM seemed to have a higher hazard ratio than African American and Chinese women with GDM compared with women without GDM of different race. In comparison to African American women without GDM, different racial women with GDM showed an increased risk of type 2 diabetes within 10 years postpartum, however, white women without GDM had a decreased risk of type 2 diabetes. The largest increased risk of type 2 diabetes over 10 years postpartum appeared in Chinese women with GDM (Hazard ratio 23.9), followed by African American women with GDM (Hazard ratio 4.92), and the smallest was seen in white women with GDM (Hazard ratio 3.57). Chinese women with a history of GDM had the highest risk of incident diabetes postpartum. The different genetic backgrounds and other risk factors among different races might contribute to the racial differences in the incidence of diabetes postpartum among women with GDM.