Influence of inflammation as measured by α-1-acid glycoprotein on iron status indicators among HIV-positive postpartum Zimbabwean women

• Published in: European journal of clinical nutrition Vol. 63; no. 6; pp. 787 - 793
• Main Authors: Rawat, R, Stoltzfus, R.J, Ntozini, R, Mutasa, K, Iliff, P.J, Humphrey, J.H
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.06.2009; Nature Publishing Group
• Subjects: acute phase proteins; acute phase response; anemia (disease); Anemia, Iron-Deficiency - complications; Biological and medical sciences; biomarkers; blood serum; Causes of; Clinical Nutrition; Cross-Sectional Studies; Cytokines; Demographic aspects; Development and progression; Diagnosis; Epidemiology; Erythropoietin; Evaluation; Feeding. Feeding behavior; Female; Ferritin; Ferritins - blood; Fundamental and applied biological sciences. Psychology; Glycoproteins; Health aspects; Health status indicators; Hemoglobin; Hemoglobins - metabolism; HIV; HIV infections; HIV seropositivity; HIV Seropositivity - blood; HIV Seropositivity - complications; human diseases; Human immunodeficiency virus; Human viral diseases; Humans; Indicators; Infectious diseases; Inflammation; Inflammation - complications; Influence; Internal Medicine; Iron; Iron deficiency; Iron deficiency anemia; Medical sciences; Medicine; Medicine & Public Health; Metabolic Diseases; Nutrient deficiency; nutritional status; original-article; Orosomucoid - metabolism; Physiological aspects; Polls & surveys; Postpartum Period; Properties; Public Health; receptors; Receptors, Transferrin - blood; Transferrin; Transferrins; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Viral diseases; Viral diseases of the lymphoid tissue and the blood. Aids; women; Zimbabwe; Zimbabwe; Africa; United States; acute phase response; TfR; AGP; SF; HIV; iron status; Iron; Evolution; Female; Woman; Human; Immunopathology; Acute; Glycoprotein; Retroviridae; Metabolic diseases; AIDS; Inflammation; Puerperium; Immune deficiency; Lentivirus; Indicator; Infection; Virus; Acids; Viral disease; Human immunodeficiency virus
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/ejcn.2008.33

Objectives: The acute phase response (APR) influences indicators of iron status. A recent WHO/CDC consultation recommended concurrent measurement of α-1-acid-glycoprotein (AGP) in surveys to control for the APR, and aid in interpreting iron status. They proposed further exploratory analyses using AGP. We examined whether the APR (measured by AGP) influences the expected relationships between iron status indicators in an HIV-infected population. Subjects: We measured hemoglobin (Hb), serum ferritin (SF), transferrin receptor (TfR), erythropoietin (EPO) and AGP in a cross-sectional survey of 643 HIV-positive Zimbabwean women. Results: SF was significantly higher in APR-positive (AGP>1 g/l) women (P<0.001), in whom there was no association between SF and Hb. TfR was inversely associated with Hb, in both APR-positive and APR-negative women (P<0.001). However, among anemic women (Hb<110 g/l), APR-positive women had marginally lower TfR concentrations (P=0.053). There was no difference in EPO response to decreasing Hb among APR-positive and APR-negative women. Conclusions: AGP captured the influence of the APR on iron indicators and their relationships with each other. The APR influenced SF and its relationship with Hb as expected. TfR behaved unexpectedly. Although TfR has been promoted as an iron indicator that is uninfluenced by the APR, TfR concentrations were depressed among anemic APR-positive women. Because TfR reflects iron deficiency and erythropoietic activity, pro-inflammatory cytokines associated with the APR may be inhibiting erythropoeisis, which is reflected by lower TfR concentrations. We support the WHO/CDC recommendation that AGP is a useful indicator to assess the influence of the APR on iron status indicators.