Predicting persistent impaired glucose tolerance in patients with gestational diabetes: The role of high sensitivity CRP and adiponectin.

BACKGROUND: To evaluate whether maternal serum adiponectin and high-sensitivity C-reactive protein (hsCRP) levels at the time of gestational diabetes mellitus (GDM) diagnosis are associated with persistent glucose intolerance in GDM women at 6 to 12 weeks postpartum.

METHODS: This is a secondary analysis of prospective randomized trial of GDM women enrolled in a behaviour education programme. Women with a GDM diagnosis ≥20 weeks were included. At the time of randomization, serum adiponectin and hsCRP levels were drawn. After delivery, women underwent a 2-hour 75-g oral glucose tolerance test at 6 to 12 weeks postpartum. Persistent impaired glucose tolerance (P-IGT) was defined as impaired fasting glucose, impaired glucose tolerance, or a diagnosis of type 2 diabetes mellitus. Regression models and receiver operator curves were used to evaluate the association between midpregnancy adiponectin and hsCRP and persistent impaired glucose tolerance.

RESULTS: Of 100 women in the trial, 63 completed postpartum glucose testing. Twenty (31.7%) of the women had P-IGT. Median hsCRP levels were higher at randomization (22-34 wk) in women with persistent impaired glucose tolerance compared with women with normal glucose tolerance (5.1 vs 3.8, P = .01). After adjustment for the original study intervention, the association between hsCRP and P-IGT persisted (odds ratio, 3.45; 95% confidence interval, 1.34-8.92; P = .01) and had good diagnostic performance with an area under the curve of 0.73. There was no difference in median adiponectin levels between groups (44.8 vs 52.0, P = .57) or in odds of P-IGT (odds ratio, 0.81; 95% confidence interval, 0.33-1.99; P = .65), and area under the curve = 0.54.

CONCLUSIONS: Midpregnancy high sensitivity CRP is a potential predictor of persistent impaired glucose tolerance diagnosed on the postpartum 2-hour 75-g oral glucose tolerance test in GDM women in the immediate postpartum period. Further investigation is needed in a larger population of women prior to using specific cut-offs for diagnostic purposes. High-sensitivity C-reactive protein levels in the immediate postpartum period should be seen as an adjunct, not a replacement, for the standard long-term screening of women with a history of a GDM pregnancy.