Insights from basic adjunctive examinations of GCK‐MODY, HNF1A‐MODY, and type 2 diabetes: A systemic review and meta‐analysis

BACKGROUND: Glucokinase maturity‐onset diabetes of the young (GCK‐MODY) is difficult to distinguish from other diabetic forms. This article aims to characterize the differences in results from routine examinations between GCK‐MODY and hepatocyte nuclear factor 1‐α (HNF1A)‐MODY or type 2 diabetes (T2D) patients in different periods of diabetes. METHODS: Ovid Medline, Embase, and the Cochrane Library were searched up until October 9, 2022 for articles containing baseline characteristics of GCK‐MODY, HNF1A‐MOFY, and T2D, excluding pregnant women. The pooled standardized mean differences were derived using a random‐effects model. RESULTS: Compared to HNF1A‐MODY, GCK‐MODY patients had lower indicators of glucose metabolism. Total triglycerides (TG) (−0.93 [−1.66, −0.21] mmol/l) were consistently lower in GCK‐MODY patients in the all‐family‐members subgroup analysis. Compared to T2D, GCK‐MODY patients were younger at diagnosis and had lower body mass index (BMI), lower high‐sensitivity C‐reactive protein (hsCRP) (−0.60 [−0.75, −0.44] mg/l), lower fasting C‐peptide (FCP), and lower 2‐hour postprandial glucose (2‐h PG). Indicators of glycated hemoglobin (HbA1c) and fasting blood glucose (FPG) were consistently lower in subgroup studies with all family members of GCK‐MODY patients as well. CONCLUSIONS: Lower HbA1c, FPG, 2‐h PG, and change in 2‐h PG may help to diagnose GCK‐MODY differentially from HNF1A‐MODY at an early stage, and lower TG may strengthen such a diagnosis in the follow‐up stages. Younger age combined with lower BMI, FCP, hsCRP, and 2‐h PG may be useful to distinguish GCK‐MODY from MODY‐like T2D, whereas results of glucose metabolism indicators such as HbA1c and FPG may not help physicians until after a long follow‐up period.