Background
Variations of serum biomarkers and bacterial diversity of the gastrointestinal tract in obese patients with diabetes or hypothyroid are poorly understood. This study broadened our understanding of recent findings in this regard.
Methods
A total of 120 obese patients (18 with diabetes, 23 with hypothyroid, and 79 patients without either diabetes or hypothyroid (control)) were recruited in this study. Serum biomarkers such as biochemical, hormonal (insulin and glucagon), and cytokine levels (IL-6, IL-1β, TNF-α, IL-10, and TGF–β 1) were measured under fasting conditions. Bacterial diversity of gut microbiota was also quantitated by real-time PCR using 16S rRNA gene-based specific primers.
Results
Average value of blood sugar (P: 0.0184), insulin, HOMA-IR, TGF-β 1, IL-6, IL-1β, IFNγ, IL-10 (Pfor each < 0.001), phylum Actinobacteria (OR: 1.5, P: 0.032), Firmicutes (OR: 0.6 P: 0.058), and Akkermansia muciniphilai (OR: 0.4, P: 0.053) was significantly different in diabetic vs. non-diabetic obese patients but was not significantly different in hypothyroid vs. non-hypothyroid obese patients. Average value of Bifidobacterium, Bacteroidetes, Prevotella spp., Bacteroides fragilis group, Clostridium cluster IV, Roseburia spp., and Firmicutes to Bacteroidetes ratio (F/B) was not significantly different between these groups either in crude or adjusted models.
Conclusion
While there are some associations between serum biomarkers or bacterial diversity with diabetes prediction in obese patients, this prognostication is less likely in obese patients with hypothyroid. Further investigation is warranted in the application of identified preclinical biomarkers in the diagnosis of diabetes or hypothyroid in obese patients.