Diagnosing GDM: Role of Simple, Cost Effective, and Sensitive DIPSI Test

A sequential explanatory mixed method study of maternal and fetal outcome in gestational diabetes mellitus using Diabetes in Pregnancy Study Group India (DIPSI) test in Puducherry

Background

Gestational diabetes mellitus in pregnancy is associated with polyhydramnios, macrosomia, and shoulder dystocia, and it also increases maternal and perinatal mortality.

Methods

This sequential explanatory mixed-method study was conducted for six months. All the pregnant women attending the outpatient department of the Obstetrics and Gynaecology Department at 24-28 weeks of gestation were subjected to universal screening with 75 gms of glucose and 2 hours of plasma glucose >140 mgs% is taken for diagnosis (according to DIPSI guidelines). After diagnosis, they were subjected to an HbA1c test. Women with HbA1c is >6.5% were excluded from the study. If pregnant women are screened negative by the DIPSI test, the test was repeated in the third trimester (32-34 weeks of gestation). Chi-square tests were used to find out the test of association for quantitative data and manual content analysis was performed for qualitative data.

Results

DIPSI test was found to decrease the adverse maternal and neonatal outcome by early screening and management. The stakeholders' perspectives identified by key informant interview were improper knowledge and awareness about the testing and others were anxiety and fear associated with the testing procedure.

Conclusions

As DIPSI test is an effective single step in screening and diagnostic test, hence all pregnant mothers should undergo this glucose challenge test in their antenatal visits.

Evaluation of the diabetes in pregnancy study group of India criteria and Carpenter-Coustan criteria in the diagnosis of gestational diabetes mellitus

OBJECTIVE

Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance that is diagnosed for the first time during pregnancy. This prospective study was undertaken to validate the single-step non-fasting 75 gm Diabetes in Pregnancy Study Group of India (DIPSI) criteria of GDM in Indian patients in comparison with the two-step fasting 100 gm glucose challenge through the Carpenter Coustan criteria (CCC).

MATERIALS AND METHODS

Two hundred patients underwent comparative testing using the DIPSI criteria and CCC. Plasma venous blood glucose levels were estimated using the hexokinase method; values ≥140 mg/dL at 2 hours were considered positive according to the DIPSI criteria. Any two values from ≥95 mg/dL for fasting, ≥180 mg/dL at 1 hour, ≥155 mg/dL at 2 hours, and ≥140 mg/dL at 3 hours were considered positive with the CCC.

RESULTS

The mean age and body mass index were 24.26±3.75 years and 20.7±3.07 kg/m2. The sensitivity, specificity, and positive and negative predictive values of the DIPSI guidelines were found as 100%, 97.14%, 83.87%, and 100%, respectively. The positive and negative likelihood ratios were 35.8 and zero. Diagnostic accuracy was found as 97.56%.

CONCLUSION

DIPSI having high sensitivity, specificity, negative predictive value and diagnostic accuracy. DIPSI offers simplicity, feasibility, convenience, and repeatability while economizing universal screening and diagnosis of GDM on a mass-scale. The DIPSI procedure has the potential to be applied to the entire obstetric population, in the implementation of public health programs to diagnose GDM in the community, thus reaching the needs of the developing world.

Evaluation of 75 g glucose load in non-fasting state [Diabetes in Pregnancy Study group of India (DIPSI) criteria] as a diagnostic test for gestational diabetes mellitus

Background & objectives:

There is no consensus regarding optimal standard for diagnosis of gestational diabetes mellitus (GDM). In this study, use of 75 g glucose load in non-fasting state [Diabetes in Pregnancy Study Group of India (DIPSI) criteria] as a diagnostic test for GDM in pregnant women was compared with different oral glucose tolerance tests (OGTTs).

Methods:

This prospective study included 936 pregnant women, who underwent plasma glucose evaluation two hours after the challenge of 75 g glucose load irrespective of the timing of last meal (DIPSI criteria for GDM). After three days, standard 75 g OGTT was done in all women irrespective of previous plasma glucose value. Accuracy of the first result was compared to OGTT using cut-offs as per the World Health Organization (WHO) and International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria for the diagnosis of GDM.

Results:

Of the total 936 pregnant women, 73 (7.8%) patients had plasma glucose value ≥140 mg/dl when measured two hours after glucose load. When comparing with the WHO and IADPSG criteria, the sensitivity values were 65.1 and 74.1 per cent, respectively, and the corresponding specificity values were 96.3 and 96.9 per cent, respectively. On comparing with the WHO OGTT, only 41 of the 73 (56.2%) were true positives, whereas when IADPSG criteria were used, true positives were 46 (63%). False negative cases were also present when classified by the WHO and IADPSG criteria though in lesser numbers than false positives. The positive predictive values (PPVs) for the WHO and IADPSG criteria were 56.1 and 63 per cent, respectively, and their corresponding negative predictive values were 97.7 and 97.9 per cent, respectively.

Interpretation & conclusions:

Our findings showed that when 75 g glucose load in non-fasting state was used as a diagnostic test for GDM, almost one quarter of patients with GDM escaped diagnosis as sensitivity values were low. On the other hand, some GDM cases were falsely labelled as normal as this test did not account for cases of fasting hyperglycaemia. In addition, comparison with other OGTTs showed low PPVs. Hence, use of DIPSI criteria for diagnosing GDM must be reconsidered till further validation.