Colombian Prediabetic Patients Classified Using Glycosylated Hemoglobin or Fasting Plasma Glucose Present Distinct Microbiome Compositions

Résumé

Prediabetes is the precursor condition to Type II diabetes (T2D), a chronic metabolic disorder characterized by insulin resistance and insufficient uptake of glucose from the bloodstream.  Current diagnostic methods glycosylated hemoglobin (HbA1c) and fasting plasma glucose (FPG) are the most widely used clinical tools yet can be inconsistent in determining prediabetic or T2D status. While current research highlights the association between gut microbiome composition and T2D, and to a lesser extent prediabetes, the difference between the microbiome composition of patients classified using HbA1c and FPG is currently unknown. To address this knowledge gap, we used 16S rRNA sequencing data collected from stool samples of a Colombian cohort, investigating the differences in the gut microbiome composition in patients classified using HbA1c compared to FPG. Although the alpha and beta diversity analysis revealed no significant differences on a community level, the core microbiome, differential abundance, and indicator taxa analyses displayed differences in gut microbial composition when comparing HbA1c and FPG prediabetic definitions with minimal overlap in identified taxa. Further, functional analysis suggested distinct metabolic profiles among HbA1c compared to FPG-classified prediabetes patients. Taken together, our study demonstrates that diagnosing prediabetes using the two diagnostic tools reveals distinct compositions of the gut microbiome, impacting both taxonomic and functional levels, underscoring the importance of employing multiple diagnostic tools in clinical practice to optimize prediabetes management.