{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T16:41:01Z","timestamp":1790527261116,"version":"4.1.0"},"reference-count":41,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T00:00:00Z","timestamp":1771545600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"UNIVERSIDAD NACIONAL DEL ALTIPLANO, PUNO, PERU","award":["(K23HL173694)"],"award-info":[{"award-number":["(K23HL173694)"]}]},{"name":"NIH","award":["K23HL173694"],"award-info":[{"award-number":["K23HL173694"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>In 2024, the World Health Organization (WHO) introduced new hemoglobin cutoffs for diagnosing anemia. The WHO also incorporated revised altitude adjustments and lowered thresholds to diagnose anemia for children aged 6\u201323 months. Puno, Peru has historically reported the highest prevalence of anemia in the country, exceeding 70% in infants and young children.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To assess the impact of the new WHO cutoffs on anemia prevalence and evaluate whether they affected the proportion of anemia attributable to iron deficiency (ID), inflammation, and other causes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A cross-sectional study was conducted among 310 children aged 6\u201359 months in Puno, Peru. Participants were recruited via convenience sampling during routine medical check-ups. Venous blood samples were analyzed using an automated hemoglobin analyzer and serum biomarker evaluations. Anemia prevalence was determined based on WHO guidelines for children aged 6\u221259 months (and 6\u221223 months and 24\u221259 months as subgroups). The ratio of anemia due to ID (Ferritin &lt;12 ng\/mL) or inflammation (IL-6\u2009&gt;\u200960 pg\/mL) was estimated using adjusted Poisson regression models, reporting prevalence ratios (PR).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Applying the new WHO guidelines, anemia prevalence changed from 50% to 42.2% in children aged 6\u221259 months (62% to 47% in children aged 6\u221223 months and from 45.9% to 40.6% in children aged 24\u221259 months). The proportion of anemia due to ID was 27.5%, due to inflammation was 45.9%, and due to other causes was 26.6%. ID was significantly associated with anemia in both unadjusted and adjusted analyses (PR: 1.4, 95% CI: 1.1\u20131.8; PR: 1.32, 95% CI: 1.0\u20131.7). The 2024 WHO guidelines did not substantially alter the estimated proportion of anemia associated with ID or inflammation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec005\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Application of the new WHO cutoffs resulted in a lower estimated prevalence of anemia among young children. ID accounted for only a small proportion of cases of anemia, emphasizing the need for further research into other causes of childhood anemia in Peru.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0342255","type":"journal-article","created":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T18:49:35Z","timestamp":1771613375000},"page":"e0342255","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["Changes in anemia prevalence and the proportion of anemia associated with iron deficiency or inflammation in young children residing in Puno, Peru: Analysis using new World Health Organization guidelines for defining anemia"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3326-0437","authenticated-orcid":true,"given":"Cinthya","family":"V\u00e1squez-Vel\u00e1squez","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benita Maritza","family":"Choque-Quispe","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Parminder S.","family":"Suchdev","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chris A.","family":"Rees","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vilma","family":"Tapia","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6543-9765","authenticated-orcid":true,"given":"Yi-An","family":"Ko","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gustavo F.","family":"Gonzales","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,2,20]]},"reference":[{"key":"pone.0342255.ref001","volume-title":"Nutritional anaemias: report of a WHO scientific group [meeting held in Geneva from 13 to 17 March 1967]","author":"WHO Scientific Group on Nutritional Anaemias & World Health Organization","year":"1968"},{"key":"pone.0342255.ref002","volume-title":"Guideline on haemoglobin cutoffs to define anaemia in individuals and populations","author":"World Health Organization","year":"2024"},{"key":"pone.0342255.ref003","volume-title":"Iron deficiency anaemia: assessment, prevention and control","author":"World Health Organization","year":"2001"},{"key":"pone.0342255.ref004","volume-title":"Accelerating anaemia reduction: a comprehensive framework for action","author":"WHO","year":"2023"},{"issue":"22","key":"pone.0342255.ref005","first-page":"400","article-title":"CDC criteria for anemia in children and childbearing-aged women","volume":"38","author":"(CDC) Centers for Disease Control","year":"1989","journal-title":"MMWR Morb Mortal Wkly Rep"},{"issue":"11","key":"pone.0342255.ref006","doi-asserted-by":"crossref","first-page":"2601","DOI":"10.1007\/s00277-019-03823-7","article-title":"Proportion of anemia attributable to iron deficiency in high-altitude infant populations","volume":"98","author":"BM Choque-Quispe","year":"2019","journal-title":"Ann Hematol"},{"key":"pone.0342255.ref007","unstructured":"INEI. Per\u00fa: Indicadores de Resultados de los Programas Presupuestales, 2023, Encuesta Demogr\u00e1fica y de Salud Familiar 2023, Informe Principal, marzo. 2024."},{"issue":"7","key":"pone.0342255.ref008","doi-asserted-by":"crossref","first-page":"1350","DOI":"10.1017\/S1368980017003858","article-title":"The WHO recommendation of home fortification of foods with multiple-micronutrient powders in children under 2 years of age and its effectiveness on anaemia and weight: a pragmatic cluster-randomized controlled trial","volume":"21","author":"YE Somass\u00e8","year":"2018","journal-title":"Public Health Nutr"},{"key":"pone.0342255.ref009","author":"MINSA","year":"2017"},{"issue":"5","key":"pone.0342255.ref010","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1038\/ejcn.2012.212","article-title":"Preventing childhood anemia in India: iron supplementation and beyond","volume":"67","author":"HPS Sachdev","year":"2013","journal-title":"Eur J Clin Nutr"},{"key":"pone.0342255.ref011","doi-asserted-by":"crossref","first-page":"234","DOI":"10.3389\/fpubh.2020.00234","article-title":"How effective is iron supplementation during pregnancy and childhood in reducing anemia among 6-59 months old children in India?","volume":"8","author":"MS Thomas","year":"2020","journal-title":"Front Public Health"},{"issue":"1","key":"pone.0342255.ref012","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1111\/nyas.14038","article-title":"Anemia in Bolivian children: a comparative analysis among three regions of different altitudes","volume":"1450","author":"D Cordero","year":"2019","journal-title":"Ann N Y Acad Sci"},{"issue":"10","key":"pone.0342255.ref013","first-page":"1","article-title":"Association between iron supplementation and the presence of diarrhoea in Peruvian children aged 6-59 months: analysis of the database of the Demographic and Family Health Survey in Peru (DHS, Peru), years 2009-2019","volume":"25","author":"VJ Valverde-Bruffau","year":"2021","journal-title":"Public Health Nutr"},{"issue":"8","key":"pone.0342255.ref014","doi-asserted-by":"crossref","first-page":"494","DOI":"10.3390\/nu8080494","article-title":"Iron fortification of foods for infants and children in low-income countries: effects on the gut microbiome, gut inflammation, and diarrhea","volume":"8","author":"D Paganini 14","year":"2016","journal-title":"Nutrients"},{"issue":"1","key":"pone.0342255.ref015","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1111\/nyas.14356","article-title":"Is the prevalence of anemia in children living at high altitudes real? An observational study in Peru","volume":"1473","author":"BM Choque-Quispe","year":"2020","journal-title":"Ann N Y Acad Sci"},{"issue":"1","key":"pone.0342255.ref016","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1186\/s40795-024-00837-x","article-title":"Evaluation of dietary composition between hemoglobin categories, total body iron content and adherence to multi-micronutrients in preschooler residents of the highlands of Puno, Peru","volume":"10","author":"BM Choque-Quispe","year":"2024","journal-title":"BMC Nutr"},{"issue":"6","key":"pone.0342255.ref017","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/j.humimm.2020.04.005","article-title":"HLA study in Amerindian Bolivia La Paz Aymaras","volume":"81","author":"A Arnaiz-Villena","year":"2020","journal-title":"Hum Immunol"},{"issue":"8","key":"pone.0342255.ref018","first-page":"961","article-title":"Perinatal variables from newborns of Aymara mothers suggest a genetic adaptation to high altitude","volume":"142","author":"M Pizarro-Ortiz","year":"2014","journal-title":"Rev Med Chil"},{"key":"pone.0342255.ref019","author":"Ministry of Health"},{"key":"pone.0342255.ref020","volume-title":"WHO guideline on use of ferritin concentrations to assess iron status in individuals and populations","year":"2020"},{"issue":"1","key":"pone.0342255.ref021","doi-asserted-by":"crossref","first-page":"741","DOI":"10.1186\/s12879-021-06470-4","article-title":"Interleukin 6 as a marker of severe bacterial infection in children with sickle cell disease and fever: a case-control study","volume":"21","author":"EM Rinc\u00f3n-L\u00f3pez","year":"2021","journal-title":"BMC Infect Dis"},{"issue":"1","key":"pone.0342255.ref022","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1186\/s40795-023-00748-3","article-title":"Anaemia, iron deficiency and inflammation prevalence in children in the Mount Cameroon area and the contribution of inflammatory cytokines on haemoglobin and ferritin concentrations: a cross sectional study","volume":"9","author":"SO Sama","year":"2023","journal-title":"BMC Nutr"},{"issue":"1","key":"pone.0342255.ref023","doi-asserted-by":"crossref","first-page":"15","DOI":"10.36393\/spmi.v37i1.844","article-title":"La nueva gu\u00eda sobre los puntos de corte de la hemoglobina para definir anemia en individuos y poblaciones","volume":"37","author":"C V\u00e1squez-Vel\u00e1squez","year":"2024","journal-title":"spmi"},{"issue":"7","key":"pone.0342255.ref024","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0307502","article-title":"Evaluation of the hemoglobin cutoff point for anemia in adult women residents of different altitudinal levels in Peru","volume":"19","author":"C V\u00e1squez-Vel\u00e1squez","year":"2024","journal-title":"PLoS One"},{"issue":"1","key":"pone.0342255.ref025","doi-asserted-by":"crossref","DOI":"10.1016\/S2214-109X(13)70001-9","article-title":"Global, regional, and national trends in haemoglobin concentration and prevalence of total and severe anaemia in children and pregnant and non-pregnant women for 1995-2011: a systematic analysis of population-representative data","volume":"1","author":"GA Stevens","year":"2013","journal-title":"Lancet Glob Health"},{"issue":"1","key":"pone.0342255.ref026","doi-asserted-by":"crossref","DOI":"10.1002\/ajh.24932","article-title":"Correcting the cut-off point of hemoglobin at high altitude favors misclassification of anemia, erythrocytosis and excessive erythrocytosis","volume":"93","author":"GF Gonzales","year":"2018","journal-title":"Am J Hematol"},{"issue":"9","key":"pone.0342255.ref027","doi-asserted-by":"crossref","DOI":"10.1002\/ajh.25194","article-title":"WHO hemoglobin thresholds for altitude increase the prevalence of anemia among Ethiopian highlanders","volume":"93","author":"K Sarna","year":"2018","journal-title":"Am J Hematol"},{"issue":"6","key":"pone.0342255.ref028","doi-asserted-by":"crossref","DOI":"10.1002\/ajh.25765","article-title":"Current WHO hemoglobin thresholds for altitude and misdiagnosis of anemia among Tibetan highlanders","volume":"95","author":"K Sarna","year":"2020","journal-title":"Am J Hematol"},{"key":"pone.0342255.ref029","doi-asserted-by":"crossref","DOI":"10.3945\/ajcn.116.142323","article-title":"Predictors of anemia in preschool children: Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project","volume":"106","author":"R Engle-Stone","year":"2017","journal-title":"Am J Clin Nutr"},{"issue":"11","key":"pone.0342255.ref030","doi-asserted-by":"crossref","first-page":"693","DOI":"10.3390\/nu8110693","article-title":"The Proportion of Anemia Associated with Iron Deficiency in Low, Medium, and High Human Development Index Countries: A Systematic Analysis of National Surveys","volume":"8","author":"N Petry","year":"2016","journal-title":"Nutrients"},{"issue":"12","key":"pone.0342255.ref031","article-title":"Intermittent iron supplementation for improving nutrition and development in children under 12 years of age","volume":"2011","author":"LM De-Regil","year":"2011","journal-title":"Cochrane Database Syst Rev"},{"issue":"11","key":"pone.0342255.ref032","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0079726","article-title":"A novel approach to evaluating the iron and folate status of women of reproductive age in Uzbekistan after 3 years of flour fortification with micronutrients","volume":"8","author":"L Hund","year":"2013","journal-title":"PLoS One"},{"key":"pone.0342255.ref033","article-title":"Daily versus alternate day oral iron therapy in iron deficiency anemia: a systematic review","author":"S Kamath","year":"2023","journal-title":"Naunyn-Schmiedebergs Arch Pharmacol"},{"issue":"1","key":"pone.0342255.ref034","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/j.ajcnut.2022.11.023","article-title":"Effects of iron supplementation on neural indices of habituation in Bangladeshi children","volume":"117","author":"LM Larson","year":"2023","journal-title":"Am J Clin Nutr"},{"issue":"12","key":"pone.0342255.ref035","doi-asserted-by":"crossref","first-page":"6117","DOI":"10.3390\/ijerph20126117","article-title":"Evaluating the Diagnostic Performance of Hemoglobin in the Diagnosis of Iron Deficiency Anemia in High-Altitude Populations: A Scoping Review","volume":"20","author":"C V\u00e1squez-Vel\u00e1squez","year":"2023","journal-title":"Int J Environ Res Public Health"},{"issue":"1","key":"pone.0342255.ref036","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1111\/nyas.14996","article-title":"Diagnosing anemia: Challenges selecting methods, addressing underlying causes, and implementing actions at the public health level","volume":"1524","author":"MN Garcia-Casal","year":"2023","journal-title":"Ann N Y Acad Sci"},{"issue":"3","key":"pone.0342255.ref037","doi-asserted-by":"crossref","first-page":"385","DOI":"10.1002\/(SICI)1096-8644(199807)106:3<385::AID-AJPA10>3.0.CO;2-X","article-title":"Hemoglobin concentration of high-altitude Tibetans and Bolivian Aymara","volume":"106","author":"CM Beall","year":"1998","journal-title":"Am J Phys Anthropol"},{"issue":"1","key":"pone.0342255.ref038","doi-asserted-by":"crossref","first-page":"204","DOI":"10.1111\/nyas.14136","article-title":"The increase in hemoglobin concentration with altitude varies among human populations","volume":"1450","author":"M Gassmann","year":"2019","journal-title":"Ann N Y Acad Sci"},{"issue":"1","key":"pone.0342255.ref039","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0226846","article-title":"Age and altitude of residence determine anemia prevalence in Peruvian 6 to 35 months old children","volume":"15","author":"RA Accinelli","year":"2020","journal-title":"PLoS One"},{"issue":"1","key":"pone.0342255.ref040","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1111\/nyas.14520","article-title":"Changes in hemoglobin levels with age and altitude in preschool-aged children in Peru: the assessment of two individual-based national databases","volume":"1488","author":"GF Gonzales","year":"2021","journal-title":"Ann N Y Acad Sci"},{"issue":"1","key":"pone.0342255.ref041","doi-asserted-by":"crossref","first-page":"26","DOI":"10.20529\/IJME.2023.064","article-title":"Mandatory fortification of rice in the public distribution system in India: An ethics perspective","author":"J Muralidharan","year":"2024","journal-title":"Indian J Med Ethics"}],"container-title":["PLOS One"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0342255","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T18:49:46Z","timestamp":1771613386000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0342255"}},"subtitle":[],"editor":[{"given":"Raquel","family":"Inocencio da Luz","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,2,20]]},"references-count":41,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,2,20]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0342255","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,20]]}}}