Study of Soluble Transferrin Receptor/Log Ferritin Ratio as a Determinant of Body Iron in Young Healthy Non Pregnant Females

Abstract

Introduction: Iron deficiency is the most common nutritional deficiency which affects young females in India. A battery of diagnostic tests is available these days which can diagnose this condition. However, to arrive at a particular marker which can tell about the iron status of healthy and non anaemic females becomes more promising as timely preventive interventions may be started. Aim: To determine the role of soluble Transferrin Receptor (sTfR) and index based on it in determining the body iron status in young non anaemic females. Materials and Methods: We undertook a cross-sectional study and recruited 200 female students (in the age group of 18-22 years) of SGT University; who volunteered to participate. Only those with haemoglobin (Hb)>12 gm/dL upon screening were included in the study. Blood samples were taken from the participants and routine haematological parameters were measured i.e., haematocrit, Mean Corpuscular Volume (MCV), Mean Corpuscular Haemoglobin Concentration (MCHC), Mean Corpuscular Haemoglobin (MCH), platelet count, red cell count and Total Leukocyte Count (TLC) to rule out anaemia and inflammation. Further we measured the iron markers like serum ferritin, transferrrin, iron, Total Iron Binding Capacity (TIBC) and Transferrin Saturation (TSAT) and sTfR along with the calculation of a ratio i.e., sTfR/log ferritin ratio (R/F ratio). This ratio was correlated with the traditional iron markers using Pearson’s correlation coefficients. Receiver Operating Characteristic (ROC) curve was used to arrive at the desired sensitivity and specificity for a particular test at a particular cut off level. Results: The sTfR/log ferritin (R/F ratio) had better discriminative power compared to sTfR or serum ferritin alone to distinguish between iron deficient and non iron deficient population. It had the best combination of sensitivity and specificity at a cut off value of 1.575 derived from ROC (AUC 0.9809) and identified 108/200 (54%) subjects to be iron deficient with a good sensitivity (98.18) and specificity (87.5%). Conclusion: Significant numbers of healthy females were found to be iron deficient and therefore accurate analysis of iron status will aid in undertaking timely preventive intervention. R/F ratio at a cut off value of 1.575 can become a good screening test in bringing forth such individuals and providing an insight towards their body iron status.

Keywords

• anaemia
• iron stores
• serum transferrin receptor