Association of serum trimethylamine oxide with red blood cell parameters in patients with chronic kidney disease

Objectives: The present study was designed to determine the relationship between serum TMAO levels and red blood cell (RBC) parameters in patients with chronic kidney disease (CKD). Material and Methods: This was a case–control study involving 100 subjects comprising 50 CKD patients (25 patients with mild anemia and 25 patients with severe anemia) and 50 apparently healthy controls recruited from April to December 2023. The TMAO levels were measured using Sandwich-based Enzyme-Linked Immunosorbent Assay kit (Sulong Diagnostic Ltd, Wuham, China) while RBC parameters were measured using Automated Hematology Analyzer (Mindray BC-6800, Shenzhen, China). Data were analyzed using GraphPad Prism version 8.0 (San Diego, California, USA) and presented as mean ± SD with P < 0.05 considered significant. Results: The mean value of TMAO (ng/mL) was 189.4 ± 2.4 in CKD with severe anemia, 122.3 ± 1.6 in CKD with mild anemia, and 36.4 ± 2.7 in control. Serum TMAO showed significant negative correlation with RBC ( P = 0.003), hemoglobin (Hgb) ( P = 0.002), hematocrit ( P = 0.004), mean cell volume ( P = 0.0240), mean cell Hgb ( P = 0.018), and mean cell Hgb concentration ( P = 0.001) but a significant positive correlation with erythropoietin ( P = 0.029) and rticulocyte ( P = 0.022). Conclusion: Serum TMAO levels showed significant association with markers of anemia in CKD suggesting a potential therapeutic target for anemia in patients with CKD.