Annual T2D screening delivers economic gains in women with GDM history

A study from Singapore shows that universal annual screening for type 2 diabetes (T2D) cuts the economic and societal burden of delayed T2D diagnosis in women with a history of gestational diabetes (GDM).

Compared with triennial screening, universal annual screening reduced costs by S$1 million and increased quality-adjusted life-years (QALY) by 1.3 thousand. When compared against elective screening, the cost reduction with annual screening was markedly greater at S$19.4 million, while QALY was up by 3.8 thousand. [Value Health Reg Issues 2025;doi:10.1016/j.vhri.2024.101048]

“Universal annual screening was [the dominant] strategy compared with strategies with less frequent screening given that it increased QALY while reducing cost, which suggests that annual screening is the optimal strategy for Singapore,” said the researchers.

They noted that the more pronounced improvement in QALY implies that the efficacy of screening and the associated reduction in T2D complication rates appear to have sprung more from the improvement in health-related quality of life rather than from an extension in lifespan.

Although increased screening rates meant higher screening costs, this eventually translated to lower T2D-related expenses, the researchers explained. “[D]espite an increase in T2D diagnoses and associated T2D treatment, [there were fewer complications. Also,] the reductions in T2D-related cost were larger than the increases in screening costs. As a result, strategies with more frequent screening were cost-saving measures compared with strategies with less frequent screening.”

Urgent need for appropriate screening strategies

Several guidelines recommend diabetes screening for mothers diagnosed with GDM, as GDM increases the maternal risk of developing T2D, the researchers noted.

In Singapore, the Ministry of Health recommends a 75-g 2-hr OGTT* 6–12 weeks postpartum, followed by lifelong screening for the development of prediabetes or diabetes at least once every 3 years. “[However,] only 54 percent of women belonging to this risk group attend the first postpartum diabetes screening in Singapore, with the proportion screened rapidly declining after the first year postpartum,” they said.

This lack of screening uptake means that a substantial fraction of individuals with T2D may go undiagnosed. Globally, about one in two T2D cases remains undiagnosed. [https://www.ncbi.nlm.nih.gov/books/NBK581940, accessed 30 March 2025; Diabetes Res Clin Pract 2022;183:109118; Diabetes Res Clin Pract 2014;103:150-160]

“[W]omen are at risk of delayed diagnosis and interventions which, in turn, would lead to increased risk of diabetes-related complications,” the researchers said.

“Therefore, there is an urgent need to implement appropriate screening strategies that may detect glycaemic abnormalities at early stages, thus allowing timely and cost-effective interventions for diabetes-related complications, to reduce further morbidity and mortality,” they said.

The reference population comprised pregnant women with GDM from the GUSTO** cohort (n=201). Five screening strategies were compared: universal annual screening, elective screening, universal screening at 1 year postpartum, triennial screening, and no screening. The OGTT was selected as the T2D screening tool across all strategies. Results per 6,500 cases of GDM were reported.

“[T]here are no clear recommendations in relation to lifelong screening for T2D … The existing gap in health economic evaluations in this area, the present context of Singapore waging war against diabetes, and the current economic landscape make this study timely and relevant,” said the researchers.

“[O]ur study highlights the importance of more comprehensive interventions after GDM and, in general, the need for cost-effectiveness evaluations of diabetes prevention programmes,” they concluded.

Shifting screening costs from personal expenses to government subsidies and diabetes awareness campaigns may improve screening uptake.