VOLUME 18 (Supplement)

Serum ferritin, insulin, and c-reactive protein as early biochemical indicators for gestational diabetes mellitus among a Filipino population in Manila

Gestational diabetes mellitus (GDM) is one of the metabolic diseases that affects pregnant women. GDM diagnosis is done during the late second or early third trimester, which may be too late to prevent complications. Objective: The study aimed to determine the association between serum ferritin, insulin, and CRP measurements, alone or in combination, and GDM. Methods: A prospective cohort study was done longitudinally over the three trimesters of gestation on 118 Filipino pregnant women who were 20-45 years old, had no recognizable diabetes, and were free from cardiovascular and other inflammatory disorders- thirty-six (36) with GDM and 82 without GDM. Ferritin, insulin, and CRP were measured in the first, second, and third trimesters of pregnancy. GDM diagnosis was done by OGTT at 28-32 weeks of gestation. Serum ferritin and insulin were determined by sandwich ELISA and CRP by solid-phase sandwich-format immunometric assay. Results: Women with GDM had higher ferritin levels in the first, second, and third trimesters at 30.47, 20.76, and 13.68 (ng/ml), respectively than in the non-GDM group at 27.41, 13.32, and 13.02 (ng/ml), respectively. Differences in the means of CRP and ferritin levels among women with GDM across the three trimesters were significant at p < 0.01. When tested individually, CRP and ferritin were significantly associated with GDM in the first at p<0.05 and second at p<0.01 trimester. In combination, the effects of ferritin and CRP (R-value=0.280>) were significant in the first trimester. Insulin in the GDM group was higher in the second trimester at 7.36 (μIU/ml) than in the non-GDM group at 7.15 (μIU/ml). Differences in means of insulin in the three trimesters were not significant. CRP was higher in the GDM group in the first trimester at 5.25 (mg/L), and the second trimester at 6.11 (mg/L), than in the non-GDM group at 5.00 (mg/L), and 5.82 (mg/L) in the first and second trimesters, respectively. Conclusions: In the first trimester of pregnancy, the combined effects of ferritin and CRP can enhance early detection of GDM risk. In the second trimester, the combination of ferritin and CRP, and the combination of ferritin and insulin can serve as potential biochemical indicators of GDM.