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.