Association between serum transferrin receptor levels and malaria recurrence in a malaria endemic area in Tanzania

Background: The relationship between body iron levels and malaria presents a complex interaction that provide variable and contradicting results. We designed a study to investigate associations between concentrations of biomarkers of body iron and malaria recurrence among children.
Methods: We conducted a longitudinal descriptive community based study in a malaria endemic area in north- eastern Tanzania. The study involved 428 children of ≤5 years of age who were positive for malaria. Over a period of 6 months, sick children visited the study clinic for screening of malaria and measurement of iron storage biomarkers by serological assays. Correlations between levels of biomarkers and malaria was determined by Spearman correlations and Mann-Whitney U-Test. Associations between malaria recurrence and serum levels of iron biomarkers were determined by odds ratio (OR) with significance cut-off points of <0.15 in univariate and <0.05 in multivariate logistic regression analyses.
Results: Only serum Transferrin Receptor (sTfR) levels had a positive correlation with malaria recurrence. When Mann-Whitney U test was used higher Hepcidin, sTfR and Leptin levels were significantly associated with malaria recurrence when malaria incidence was grouped into ‘once’ versus ‘more than once’. When malaria incidence was recategorised to ‘up to twice’ versus ‘more than twice’, only higher level of sTfR was associated with recurrence of malaria. With univariate regression analysis, only sTfR was found to be significantly associated with malaria recurrence, although this associated was not observed in Multivariate analyses.
Conclusion: Despite the absence of association in multivariate analyses, univariate analyses suggest elevated levels of sTFR as a likely predictor of Plasmodium falciparum re-infection.