Jeanette Wahlberg
Accepted Abstracts: J Diabetes Metab
Objective: To investigate associations between glucose levels at the time of diagnosis of gestational diabetes (GDM) and infant birth weight and the long-term risk of manifest diabetes mellitus (DM) in the mother. Research design and methods: In a nationwide Swedish study GDM pregnancies (n=2085) was compared with non-GDM pregnancies (n=3683). GDM was defined as capillary blood glucose (cB-glucose)≥9.0mmol/l (plasma glucose ≥10.0mmol/l) after a 75g oral glucose tolerance test (OGTT). Follow up questionnaires 8.5-13.5 yrs. after initial diagnosiswere answered by 1324 GDM women (65%).In order to validate questionnaire data 51 women from a local area of South East of Swedenagreed to participate in a clinical follow-up including 75g OGTT. Results: GDM women were older, shorter, had higher BMI, and higher mean infant birth weight compared with controls (3683g vs. 3543g, P<0.001).In multiple linear regression analysis, birth weight was positively correlated to fasting cB-glucose at GDM diagnosis (P<0.001), increased week of gestation (P<0.001) and BMI before pregnancy (P<0.046), while increasing levels of 2h OGTTcB-glucosewere not related. Infants born to mothers with fasting cB-glucose ≤5.0 mmol/l had no increased mean birth weight or macrosomia compared to controls. In the long term follow up 334/1324 women (25 %) of the GDM women had developed DM, 215 T2D, 46 T1D and 72 unclassified. In logistic regression fasting cB-glucose and 2h OGTT cB-glucose at diagnosis of GDM, high BMI before pregnancy, as well as origin outside Europe were risk factors for manifest DM.In the clinical follow up of 51 women 12/51 (24%) reported DM, and in addition 4 more patients were diagnosed with DM after OGTT, increasing the prevalence to 16/51 patients (31%). Moreover, 22/51 were diagnosed with impaired fasting plasma glucose (IGF) or impaired glucose tolerance (IGT), left only 13 (24%) with normal glucose tolerance. Conclusions: Fasting blood glucose at diagnosis of GDM gives important information about pregnancy outcome and future risk for maternal diabetes and has to be measured in addition to OGTT 2-hour glucose values. Our data suggests that all women with GDMdiagnosed by 2hour plasma glucose ≥10.0mmol/l after 75g OGTT must be recommended life-long followup regarding glucose disturbances.