Nomograms for incident risk of post-partum type 2 diabetes in Chinese women with prior gestational diabetes mellitus.

Abstract

Counselling patients with gestational diabetes mellitus (GDM) on their individual risk of post-partum type 2 diabetes (T2D) is challenging. This study aimed to develop nomograms for predicting incident risk of post-partum T2D in women with GDM diagnosed by WHO 1998 criteria. We performed a retrospective cohort study in 1263 Chinese women with GDM, of whom 83 were diagnosed as T2D at 2.3years post-partum. Multivariate Cox proportional hazards models were used to investigate the independent predictors for post-partum T2D. The results of multivariate analyses were used to formulate nomograms for predicting incident risk of post-partum T2D. The predictive accuracy was evaluated using the area under the receiver operating characteristic curve (AUROC). On multivariate analysis, independent predictors of post-partum T2DM in women with GDM included family history of diabetes [hazard ratio (HR) and its 95% confidential interval (95% CI): 2.06 (95% CI: 1.32-3.22)], history of pregnancy-induced hypertension [3.11 (95% CI: 1.86-5.21)], pre-pregnancy BMI [1.00, 1.90 (95% CI: 1.14-3.16), and 3.67 (95% CI: 2.03-6.63) for BMI <24, 24-28, and ≥28kg/m2 ], and 2-hour glucose at 26-30 gestational weeks [1.00, 2.84 (95% CI: 1.42-5.69), and 9.42 (95% CI: 4.46-19.90) for 2-hour glucose at 7.8 ~ <8.5, 8.5 ~ <11.1, and ≥11.1mmol/L). The overall AUROC of nomogram was 82.8% (95% CI: 78.1%-87.5%), with AUROCs of 85.9% (95% CI: 79.7%-92.1%) and 83.2% (95% CI: 77.9%-88.6%) for post-partum 2-year and 3-year risk of T2D, respectively. This easy-to-use nomogram, with non-invasive clinical characteristics, can accurately predict the risk of post-partum T2D in women with GDM. It may facilitate risk communication between patients and clinicians.