A Preliminary Report on the Pattern of Plasma Homocysteine- Protein Ratio among Pregnant Women in Lagos, Nigeria

Abstract

In plasma, homocysteine (Hcy) is majorly bound to protein, and have been significantly associated with adverse obstetric outcomes such as placental abruption or placental infarction, unexplained recurrent fetal loss, and pre-eclampsia among others; including the possibility of predicting women at risk of these conditions.Estimated Hcy levels have been observed to vary significantly with age, sex, lifestyles, hereditary factors, and ethnicity among several other confounding factors. However, the evaluation of homocysteine-protein ratio (Hcy/Pro) may provide a more reliable biomarker by adjusting for variations in serum proteins. The aim of the study was to determine the pattern of Hcy/Pro among pregnant Nigerian females and evaluate possible associations with some haematological variables (Haemoglobin-Hb; Mean cell volume-MCV; Mean cell haemoglobin concentration-MCHC; White blood cell count-WBC and Platelet count-PLT).This study was an observational, hospital based, Cross-Sectional study comprising 130 pregnant women (cases) and 130 non-pregnant women (controls). The participants were recruited from the Lagos University Teaching Hospital (LUTH).Structured questionnaires were applied to obtain demographic, medical, socio-economic, and nutritional histories. Plasma Hcy was evaluated using Enzyme linked Immunosorbent Assay (ELISA), and Plasma protein was evaluated using a fully automated Beckman Synchron LX20 by Beckman Coulter, Inc., 250 S. Kraemer Blvd. Brea, CA 92821, USA. Statistical analyzes were performed using SPSS version 23. Reference range for Hcy/Pro for non-pregnant females was estimated to be 0.050 – 0.098µmol/g. Homocysteine-protein ratio was observed to decline progressively throughout pregnancy (F=36.565; p=0.0001). The mean Hcy/Pro of control group participants (0.074 ± 0.012 µmol/g) was significantly higher than the 0.057 ± 0.019 µmol/g reported for the study group (p=0.001). Homocysteine-protein ratio correlated negatively with gestational age (GA) of study group participants (r= - 0.364; p=0.003).The Hcy/Pro showed a progressive decline throughout pregnancy, compared to total plasma Hcy pattern, and may be a truer reflection of plasma homocysteine pattern in pregnancy.

Keywords: Homocysteine-protein ratio, homocysteine, pregnancy, proteins