Association of hyperglycaemia during pregnancy with future risk of type 2 diabetes among women: a nested case-control study using a US health administrative database.

OBJECTIVE: To quantify the risk of type 2 diabetes mellitus (T2DM) among women based on the number of abnormal values on 100-gram oral glucose tolerance test (OGTT). DESIGN: A 1:5 matched case-control study nested to a cohort of pregnant women was conducted. Conditional logistic regression was employed to estimate the independent association between glucose levels and future risk of T2DM. SETTING: This study used a large multicentre electronic health records (EHRs) database-Cerner Real-World Data (CRWD) between 2000 and 2016, covering approximately 21.6% of US inpatient EHRs. PARTICIPANTS: We identified a cohort of 130 172 pregnant women registered in the CRWD between 2000 and 2016 and were followed up until the end of 2016. A nested case-control study was conducted within this cohort, comprising 1 390 cases and 6 950 matched controls. RESULTS: Adjusted Odds Ratios for the risk of T2DM among women with one abnormal value and at least two abnormal values on OGTT diagnosed by the National Diabetes Data Group criteria, as compared with those women with normal OGTT values, were 5.69 (95% CI 4.34 to 7.47) and 13.20 (95% CI 10.52 to 16.57), respectively. CONCLUSION: Women with one abnormal value on the 100-gram OGTT had a significantly higher risk of developing T2DM compared with women with normal glucose value.