{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T03:04:07Z","timestamp":1782529447104,"version":"3.54.5"},"reference-count":20,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2019,2,16]],"date-time":"2019-02-16T00:00:00Z","timestamp":1550275200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Serum ferritin concentration is the preferred biomarker to assess population iron status in the absence of inflammation. Interpretation of this biomarker is complicated in populations with a high burden of infection, however, because inflammation increases serum ferritin concentration independently of iron status. We aimed to compare estimates of iron status of Kenyan pregnant women, with circulating ferritin concentrations adjusted for inflammation using newly proposed methods by the BRINDA project, or using previously proposed adjustment methods. We re-analyzed data from pregnant Kenyan women living in a rural area where malaria is highly endemic (n = 470) or in an urban area (n = 402). As proposed by the BRINDA group, we adjusted individual ferritin concentration by internal regression for circulating concentrations of C-reactive protein (CRP) and \u03b11-acid glycoprotein (AGP). Other adjustment methods comprised: (a) arithmetic correction factors based on CRP or AGP; (b) exclusion of subjects with inflammation (CRP &gt;5 mg\/L or AGP &gt;1 g\/L); and (c) higher ferritin cut-off value (&lt;30 \u03bcg\/L). We additionally adjusted for Plasmodium infection as appropriate. Lastly, we assessed iron status without adjustment for inflammation. All correction methods increased prevalence of iron deficiency compared to the unadjusted estimates. This increase was more pronounced with the internal regression correction method. The iron deficiency prevalence estimate increased from 53% to 87% in rural Kisumu study and from 30% to 41% in the urban Nairobi study after adjusting for inflammation (CRP and AGP) using the BRINDA internal regression method. When we corrected for both inflammation and Plasmodium infection using the regression correction, it resulted in lower prevalence estimates compared to uninfected women. Application of linear regression methods to adjust circulating ferritin concentration for inflammation leads to markedly decreased point estimates for ferritin concentration and increased estimates for the prevalence of iron deficiency in pregnancy.<\/jats:p>","DOI":"10.3390\/nu11020420","type":"journal-article","created":{"date-parts":[[2019,2,17]],"date-time":"2019-02-17T22:11:50Z","timestamp":1550441510000},"page":"420","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Iron Status of Kenyan Pregnant Women after Adjusting for Inflammation Using BRINDA Regression Analysis and Other Correction Methods"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8358-4448","authenticated-orcid":false,"given":"Martin N.","family":"Mwangi","sequence":"first","affiliation":[{"name":"Division of Human Nutrition, Wageningen University and Research, P.O. Box 9101, 6700HB Wageningen, The Netherlands"},{"name":"Training and Research Unit of Excellence, Department of Public Health, College of Medicine, University of Malawi, Private Bag 360, Chichiri, Blantyre 3, Malawi"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth","family":"Echoka","sequence":"additional","affiliation":[{"name":"Centre for Public Health Research, Kenya Medical Research Institute (KEMRI), P.O. Box 54840 00200, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1489-3797","authenticated-orcid":false,"given":"Marthe","family":"Knijff","sequence":"additional","affiliation":[{"name":"Division of Human Nutrition, Wageningen University and Research, P.O. Box 9101, 6700HB Wageningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lydia","family":"Kaduka","sequence":"additional","affiliation":[{"name":"Centre for Public Health Research, Kenya Medical Research Institute (KEMRI), P.O. Box 54840 00200, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brenda G.","family":"Werema","sequence":"additional","affiliation":[{"name":"Danone Nutricia Africa &amp; Overseas, Kenrail Towers, Ring Road Parklands, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Frida M.","family":"Kinya","sequence":"additional","affiliation":[{"name":"Danone Nutricia Africa &amp; Overseas, Kenrail Towers, Ring Road Parklands, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard","family":"Mutisya","sequence":"additional","affiliation":[{"name":"Centre for Public Health Research, Kenya Medical Research Institute (KEMRI), P.O. Box 54840 00200, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erastus M.","family":"Muniu","sequence":"additional","affiliation":[{"name":"Centre for Public Health Research, Kenya Medical Research Institute (KEMRI), P.O. Box 54840 00200, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ay\u015fe Y.","family":"Demir","sequence":"additional","affiliation":[{"name":"Laboratory for Clinical Chemistry, Meander Medical Centre, Maatweg 3, 3813 TZ Amersfoort, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hans","family":"Verhoef","sequence":"additional","affiliation":[{"name":"Division of Human Nutrition, Wageningen University and Research, P.O. Box 9101, 6700HB Wageningen, The Netherlands"},{"name":"Cell Biology and Immunology Group, Wageningen University and Research, P.O. Box 338, 6700AH Wageningen, The Netherlands"},{"name":"MRC Unit, The Gambia, Atlantic Boulevard, Fajara, Republic of Gambia"},{"name":"MRC International Nutrition Group, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0765-8350","authenticated-orcid":false,"given":"Raphaelle","family":"Bourdet-Sicard","sequence":"additional","affiliation":[{"name":"Danone Nutricia Research, route de la Vauve, 91120 Palaiseau, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,16]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization, Centers for Disease Control and Prevention (2007). Assessing the Iron Status of Populations, World Health Organization."},{"key":"ref_2","unstructured":"World Health Organization (2011). 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Nutr."}],"container-title":["Nutrients"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-6643\/11\/2\/420\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T12:32:41Z","timestamp":1760185961000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-6643\/11\/2\/420"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,2,16]]},"references-count":20,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2019,2]]}},"alternative-id":["nu11020420"],"URL":"https:\/\/doi.org\/10.3390\/nu11020420","relation":{},"ISSN":["2072-6643"],"issn-type":[{"value":"2072-6643","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,2,16]]}}}