Baseline Iron Status and Indices of Oxidative Stress in a Cohort of Pregnant Women in Kinshasa, DR Congo

Abstract

Objective: To determine baseline iron and oxidative status in a cohort of pregnant women before iron supplementation in our setting. Background: Screening of iron deficiency before supplementation during pregnancy has been scarce. Therefore, following routine iron supplementation confounding results might be found in outcomes of groups of patients considered. Taking in account that body/serum iron status is reportedly linked to maternal oxidative status, we aimed to associate assessment of baseline iron and oxidative status of women in need of oral supplementation during pregnancy. Methods: This is a cross-sectional study concerning 74 women attending antenatal care at the University Clinics of Kinshasa from September 2017 throughout June 2018, with a singleton pregnancy not exceeding 19 weeks, regardless of age and parity. Variables of the study included sociodemographic and anthropometric ones along with parameters of iron status (hemoglobin, hematocrit, ferritin, serum iron, transferrin and iron saturation capacity). Oxidative status was assessed using superoxide dismutase (SOD) and uric acid as antioxidants, while oxidant agents were oxidized LDL and blood glucose (beside serum iron and ferritin). According to local standards anemia was defined as hemoglobin < 10 g/L and pathologic serum ferritin as < 15 ng/ml. For statistical calculations we used t-test, chi-square test and Pearson’s correlation test, the significance being stated at p ≤ 0.05. Results: At recruitment (15.9 ± 1.7 9 week gestational age) mean hemoglobin value of the overall study group was 10.3 ± 1.5 g/dl. Anemia was diagnosed to 39 women that represented 52.2% of the study group, most of anemic women belonging to low socioeconomic sub-group (69.2% vs 29%; P < 0.001). The majority was para 2, with average weight of 70.2 ± 14.5 Kg (P not significant between sub-groups) and BMI of 26 ± 5.2 Kg/m2 (P < 0.01). The proportion of obeses was 18.9%. The proportion of intestinal parasitosis was significantly higher among anemic women (61.5% vs 34.3%; P < 0.02) that had lower alimentary iron intake (22.8 ± 4.9 gr/day vs 31.4 ± 9.5 gr; P < 0.001). Of markers of iron status serum ferritin and iron were lower in anemic women (7.5 ± 3.9 ng/ml vs 35.7 ± 17.1 ng/ml; P < 0.001 and 52.7 ± 38.9 μg/dl vs 96.2 ± 41.8 μg/dl, respectively. Both sub-groups were similar in serum transferrin. As of markers of oxidative stress anemic women had significantly higher superoxide dismutases (SOD) (1056.4 ± 762.1 UI/L vs 682.6 ± 543.9 UI/L (P < 0.02) and oxidizedd anti LDL Ac (439.6 ± 209.5 UI/L vs 192.8 ± 136.3 UI/L (P < 0.001). Serum iron, ferritin, SOD and oxidized LDL were more likely to assess iron and oxidative status in our setting. Conclusion: The rate of anemic mothers found in our study (52.2%) has been quite constant in our setting for years, meaning endemicity. Serum iron and ferritin were significantly lower in anemic women, which is supportive of routine iron supplementation during pregnancy. Significantly higher level of SOD and oxidized LDL in anemic women suggests that maternal anemia may count into oxidative stress likely to be found in these women.