A new approach to the effect of inflammation on plasma thiamine status in critically ill patients: Kursat-Tugra Equation

Thiamine plays a crucial role on energy metabolism. In critically ill patients, the provision of adequate nutritional support may lead thiamine deficiency. Thiamine deficiency may prevent to use of energy in metabolism in critical illness. This condition may create vicious circle, lead to severe thiamine depletion. Therefore, the determine of thiamine status is important. The analysis of plasma thiamine analysis to determine thiamine level is affected by inflammation related to critical illness. Erythrocyte thiamine pyrophosphate (eTPP) concentration, which is another method for assessing thiamine status, is not affected by inflammation. However, it is a relatively more difficult technical method. The aim of study was to determine the effect of inflammation on plasma thiamine level by accepting the eTPP level as the gold standard in critically ill patients. Patients and methods This study performed prospectively in medical intensive care unit (ICU). A total of 96 samples from 48 critically ill participants aged 18 years and older who did not receive IV thiamine supplementation during the study period were included in the study. Plasma thiamine and eTPP values measured using high pressure liquid chromatography (HPLC). Serum CRP value analyzed by turbidimetric analysis to determine inflammation. The multiple linear regression was performed to determine the relationship between plasma thiamine and serum CRP levels to predict eTPP concentrations. Results The mean age of participants was 62.6±7.98. The mean APACHE II score was 14.2±7.1. The mean plasma thiamine value was 50.6 ± 23.0 ng/g Hb. The median eTPP concentration of participants was 597.2 (IQR: 361.2–890.7) ng/g Hb. The median serum CRP value was 116.3 (IQR: 67.8–198.7) mg/L. The multiple lineer regression showed statistically significant model which is “eThDP level (ng/g Hb) = 444.321 + (4.916*Plasma tiamin level (ng/g Hb)) -(0.231*CRP value (mg/L))” (R2 = 0.78, p = 0.020). Conclusion This multiple linear regression based equation named Kursat-Tugra Equation can present an information about the actual level of thiamine status in the presence of inflammation.