Clinical utility of calculated haematological parameters in the diagnosis of iron deficiency anaemia in pregnant women

Iron deficiency anaemia (IDA) is a common condition during pregnancy. The aim of the present study was to determine the diagnostic accuracy measures and define the optimal parameters for diagnosing IDA. Simple parameters, such as erythrocyte count (E), iron (Fe), haematocrit (HCT), mean corpuscular volume of erythrocytes (MCV), and red blood cell distribution width (RDW), were included and several ratios were calculated (Fe/E, MCV/RDW, RDW/E, RDW/Fe, and RDW/HCT). Additionally, a scoring model was proposed. A total of 623 pregnant women were included in the present study, and the blood was obtained a day before or on the day of delivery. Simple parameters and calculated ratios were determined. The clinical criterion for IDA diagnosis was defined based on the World Health Organization threshold of haemoglobin <110 g/l, and pregnant women were classified as anaemic or non-anaemic based on this metric. The values of all assessed parameters were significantly different (P<0.001) between the two groups. A weak correlation was identified for MCV, Fe/E, and MCV/RDW; a moderate correlation for E, Fe, RDW/E, and RDW/Fe; and a strong correlation for HCT and RDW/HCT. No correlation was identified for RDW. Markedly high diagnostic accuracy for IDA diagnosis was obtained with an area under the curve (AUC) of 0.921 for the calculated parameter RDW/HCT >43.64 l/lx10^-2, and an AUC of 0.973 for the simple parameter HCT ≤0.32 l/l. RDW/HCT and HCT demonstrated the highest diagnostic accuracy, and may be useful parameters in routine practice for the diagnosis of IDA.