Sharmin Jahan, M Fariduddin, Nusrat-Sultana, Yasmin-Aktar, Mashfiqul-Hasan, Sandesh-Panthi, M Atiqur Rahman and M A Hasanat
Objectives: To observe the impact of predictors [age and
body mass index
(BMI) of mother, family history of diabetes, parity, use of insulin in pregnancy, gestational age and glycemic status at diagnosis) on persistence of abnormal glucose tolerance (AGT) in GDM at 6-12 week post-partum and its relationship with cardio-metabolic risk factors. Methods: This study encompassed 108 GDM subjects [age (year, 29.4 ± 5.3); BMI (Kg/m2, 26.4 ± 4.97) mean ± SD] diagnosed by standard oral glucose tolerance test (OGTT) during index pregnancy. At 6-12 week post-partum, 75 g - 2 hr-OGTT was done to know their glycemic status. Data for predictors and cardio-metabolic risk factors were obtained from history, clinical examination and personal records. Plasma glucose was measured by glucose-oxidase method on the same day of sampling. Results: Age (yr, 31.3 ± 5.8 vs. 28.1 ± 4.5, p<0.001), BMI (kg/m2, 27.9 ± 4.7 vs. 25.3 ± 4.5, p=0.004), FPG (5.9 ± 0.21 vs. 5.3 ± 0.08 mmol/L, p=0.003) and 2-hr-OGTT values (10.7 ± 0.40 vs. 9.5 ± 0.18 mmol/L, p=0.006) (mean ± SD) along with gestational age <20 weeks (p<0.001) during detection of GDM at diagnosis, higher parity (p<0.05) and insulin use during pregnancy (p<0.001) were significantly higher in AGT than those of normal
glucose tolerance
(NGT). However, frequencies for AGT at post-partum considered on trimester of GDM detection (1st trimester: 54.5%, 2nd trimester: 46.6% and 3rd trimester: 33.3%) showed no statistical difference (χ2=2.382, p=0.304). On stratification of FPG values during GDM detection, frequencies decreased for both AGT and NGT with increments of FPG at post-partum. Frequency of AGT was significantly higher than NGT with increment of FPG (χ2=11.976, p=0.007) which was also evident on dichotomization of FPG during GDM detection (at cut-off 5.1 mmol/L: p=0.582; at cut-off 6.1 mmol/L: p=0.003 and at cut-off 7.0 mmol/L: p=0.001). Unlike overweight/obesity and family history of DM (p value 0.092 & 0.138 respectively), frequency of hypertension in AGT was higher than that of NGT (80% vs.20 %, p<0.002). FPG and 2-hr-OGTT value in 6-12 week post-partum correlated in both AGT (r=0.802, p<0.001) and NGT (r=0.296, p=0.019), FPG at detection of GDM with post-partum FPG of AGT (r=0.594, p<0.001 postpartum 2-hr-OGTT glucose in AGT (r=0.499, p<0.001). AGT correlated inversely with age of gestation at GDM detection (r=-0.196, p=0.042) whereas positively with
hypertension
(r=0.304, p<0.001) and use of insulin during pregnancy (r=0.421, pË0.001). Multiple regression revealed that age of the subjects (p=0.009) and use of insulin during pregnancy (p=0.035) were independent predictors of AGT at post-partum. Conclusion: It is concluded that advanced age, higher BMI, magnitude of both FPG and 02-hr glucose value of OGTT, earlier gestational age at diagnosis of GDM and use of insulin during pregnancy are important predictors for AGT during post-partum period and hypertension as a cardio metabolic risk factor was strongly associated with AGT.