We investigated the relationship between gestational diabetes (GDM) and the metabolic syndrome in 368 (185 European (EUR), 103 South Asian (SA) and 80 Afro-Caribbean (AC)) women studied 20.0 (18.2-22.1) months (mean (95% CI)) following a GDM pregnancy and 482 normoglycaemic women (288 EUR, 99 SA, 95 AC) with no history of GDM. Estimates of beta-cell function (%B) and insulin sensitivity (%S) were derived using the HOMA method. Analysis was by multiple linear regression including metabolic and anthropometric variables, adjusting for age, parity, time since delivery and ethnicity.
Compared to controls, women with previous GDM displayed features of the metabolic syndrome including higher BMI (27.5(26.9-28.1) vs. 24.5(24.1-24.9) kilogram per meter2, waist/hip ratio (0.83(0.82-0.84) vs 0.78(0.77-0.78)), blood pressure (systolic: 116(114-118) vs 111(110-113), diastolic: 73(72-75) vs 70(69-71) millimeters Hg), fasting triglycerides (1.2(1.2-1.3) vs 0.9(0.8-0.9) millimoles per litre), glucose (5.6(5.4-5.7) vs 4.6(4.6-4.7) millimoles per litre) and insulin (122(109-137) vs 65(58-73) picomoles per litre), all p values £0.001. There was no difference in HDL-Cholesterol and HOMA-%B. HOMA-%S was decreased in the post-GDM group (38(34-43) vs 74(66-82)%, p<0.001).
When analysis was restricted to those women with previous GDM who were normoglycaemic post-partum (133 EUR, 58 SA and 40 AC), findings were similar, although HOMA-%B was significantly higher in this group than in controls (178(161-196) vs 137(127-148)%, p<0.001). When we compared the features of those post-GDM women who were normoglycaemic, with those with abnormal glucose regulation post-partum, the striking difference was a marked reduction in beta-cell function in the latter, evidenced by similar fasting insulin levels in the face of the raised fasting glucose and a consequential reduction in HOMA-%B (119(102-140) vs 178(161-196)%; p<0.001).
We conclude that the metabolic syndrome is present in women following GDM even when they remain normoglycaemic post-partum. The progression to abnormal glucose tolerance is associated with a loss of beta-cell function.
04 - 06 Nov 2002
Society for Endocrinology