Pancreatic volume, fat content and T1 relaxation time using magnetic resonance imaging in patients with prior gestational diabetes mellitus

Purpose: To compare the volume, fat content, and T1 relaxation time of the pancreas in participants with and without prior gestational diabetes mellitus (GDM).

Methods: In this prospective case-control study, we enrolled 29 women with prior GDM, and divided them into three groups (normoglycemic, prediabetic, and diabetic) based on their glycaemic status in the postpartum period; and a group of 13 participants as controls who had normoglycemia during pregnancy. Participants underwent MR examination including an axial multi-echo DIXON-based sequence and an axial-oblique T1 mapping sequence. The average proton density fat fraction (PDFF) and T1 value of the pancreas were measured by drawing multiple circular regions of interest (ROIs). Average hepatic PDFF was similarly calculated. Pancreatic volume was computed by summating cleaned freehand ROIs outlining pancreatic parenchyma.

Results: Women were evaluated at a mean age of 32.9 ± 4.0 years and with a mean BMI of 25.2 ± 2.9 kg/m2. The median (IQR) duration of follow-up after childbirth was 24 (34-44) months. In controls, the pancreatic PDFF, T1 value, and volume were 5.4 ± 2.3%, 850.6 ± 101.6 ms, and 69.3 ± 16.2 cm³, respectively, while in subjects with a history of GDM, these values were 4.7 ± 2.0%, 844.6 ± 91.8 ms, and 69.8 ± 16.6 cm³, respectively. No statistical differences were observed (all p > 0.05). Mean hepatic PDFF was significantly higher in the diabetic and prediabetic groups (12.2 ± 6.4% and 11.0 ± 7.6% respectively) than in the control and normoglycemic groups (7.9 ± 7.3 and 4.7 ± 1.6% respectively; p -0.01).

Conclusion: We did not find any significant changes in pancreatic volume, fat content, or fibrosis in women with prior GDM and with different glycaemic categories when evaluated in the early postpartum period, compared to the control group. These findings may be a consequence of the transient state of insulin resistance in GDM and the finite duration of the disease course in new-onset prediabetes and diabetes patients.