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.

BACKGROUND: The anemia prevalence is higher in highlands populations. It is assumed that iron deficiency anemia (IDA) in children is mainly due to low dietary intake. However, other suggest that high prevalence of anemia is due to an inappropriate hemoglobin (Hb) adjustment for altitude. MATERIALS AND METHODS: Cross-sectional study conducted in 338 preschoolers (PSC) from Puno-Peru. Hb was measured in whole blood, and ferritin, Soluble transferrin receptor, and Interleukin 6 in serum.The dietary iron intake was assessed by 24-h dietary recall, using NutriCap Software. Hb concentration was assessed as adjusted or unadjusted for altitude. RESULTS: With unadjusted Hb, the anemia prevalence was 4.7%, whereas after Hb correction, the prevalence raised-up to 65.6% (p < 0.001). Reciprocally, erythrocytosis proportion decreased from 20.35 to 0.30% (p < 0.001). Total Body Iron (TBI) showed that 7.44% had ID and 0.32% had IDA. PSC with normal unadjusted Hb levels have more protein and micronutrients intake than anemic ones. PSC with erythrocytosis consumed less fat, and more niacin and ascorbic acid than anemics. Total iron intake was lower in anemic than the other groups, but without statistical significance due to the standard deviation of the data in a small number of anemic PSC (n = 16). TBI, unadjusted Hb, and adjusted Hb were not different between groups consuming or not multimicronutrients. CONCLUSIONS: The consumption of iron and iron status in children who live at high altitude is adequate, and that anemia could be due to other micronutrient deficiencies and/or that the adjustment of Hb by altitude is inappropriate.

Evaluating the Diagnostic Performance of Hemoglobin in the Diagnosis of Iron Deficiency Anemia in High-Altitude Populations: A Scoping Review.

We evaluated the available literature on the diagnostic performance of hemoglobin (Hb) in the diagnosis of iron deficiency anemia (IDA) in high-altitude populations. We searched PubMed, Web of Science, Scopus, Embase, Medline by Ovid, the Cochrane Library, and LILCAS until 3 May 2022. We included studies that evaluated the diagnostic performance (sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), receiver operating characteristic (ROC) curves, and accuracy) of Hb (with and without an altitude correction factor) compared to any iron deficiency (ID) marker (e.g., ferritin, soluble transferrin receptor (sTFR), transferrin saturation, or total body iron (TBI)) in populations residing at altitudes (≥1000 m above sea level). We identified a total of 14 studies (with 4522 participants). We found disagreement in diagnostic performance test values between the studies, both in those comparing hemoglobin with and in those comparing hemoglobin without a correction factor for altitude. Sensitivity ranged from 7% to 100%, whereas specificity ranged from 30% to 100%. Three studies reported higher accuracy of uncorrected versus altitude-corrected hemoglobin. Similarly, two studies found that not correcting hemoglobin for altitude improved the receiver operating characteristic (ROC) curves for the diagnosis of iron deficiency anemia. Available studies on high-altitude populations suggest that the diagnostic accuracy of Hb is higher when altitude correction is not used. In addition, the high prevalence of anemia in altitude regions could be due to diagnostic misclassification.

Risk of death, hospitalization and intensive care unit admission by SARS-CoV-2 variants in Peru: a retrospective study.

OBJECTIVES: Peru has had the highest death toll from the pandemic worldwide; however, it is not clear what the effects of the different variants on these outcomes are. The study aimed to evaluate the risk of death, hospitalization, and intensive care unit (ICU) admission rates of COVID-19 according to the SARS-CoV-2 variants detected in Peru from March 2020-February 2022. METHODS: Retrospective study using open-access databases were published by the Peruvian Ministry of Health. Databases of genomic sequencing, death, COVID-19 cases, hospitalization and ICU, and vaccination were used. Crude and adjusted Cox proportional hazards regressions with clustered variances were modeled to calculate the hazard ratio (HR) of outcomes by variant. RESULTS: Lambda variant had the highest risk of death (HR 1.92, 95% CI 1.37-2.68), whereas the Delta variant had the lowest risk (HR 0.50, 95% CI 0.31-0.82). Mu variant had the highest risk of hospitalization (HR: 2.39, 95% CI 1.56-3.67), Omicron the lowest (HR 0.45, 95%CI 0.23-0.90), and Gamma had the highest ICU admission rate (HR 1.95, 95%CI 1.40-2.71). CONCLUSION: SARS-CoV-2 variants showed distinctive risks of clinical outcomes, which could have implications for the management of infected persons during the pandemic.

Comparison of two isothermal methods for SARS-COV-2 screening in Callao, Peru

Objective: To compare the isothermal molecular screening techniques CPA and RT-LAMP, against the gold standard test, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and to determine its agreement. Materials and Methods: Paired comparative case-control study. For the evaluation of the CPA method, 70 cases and 130 controls were used, while for RT-LAMP, 30 cases and 70 controls were used. The sensitivity and specificity of both tests were calculated. Subsequently, the bias-corrected Kappa index was calculated by resampling. Results: Both techniques have adequate and equivalent values of sensitivity (RT-LAMP: 82.8%, CPA: 83%) and specificity (RT-LAMP and CPA: 91.5%), as well as a high concordance (88%), and Kappa-index (0.72). Conclusion: Both isothermal molecular screening techniques are suitable for SARS-CoV-2 screening, with a similar sensitivity and specificity.

Objetivo : Comparar las técnicas de cribado molecular isotérmico CPA y RT-LAMP, frente a la prueba de referencia, la reacción en cadena de la polimerasa cuantitativa de transcripción inversa (RT-qPCR), y determinar su concordancia. Materiales y métodos : Estudio comparativo de casos y controles emparejados. Para la evaluación del método CPA se utilizaron 70 casos y 130 controles, mientras que para la RT-LAMP se utilizaron 30 casos y 70 controles. Se calcularon la sensibilidad y la especificidad de ambas pruebas. Posteriormente, se calculó el índice Kappa corregido por sesgo mediante un nuevo muestreo. Resultados: Ambas técnicas presentan valores adecuados y equivalentes de sensibilidad (RT-LAMP: 82,8 %, CPA: 83 %) y especificidad (RT-LAMP y CPA: 91,5 %), así como una alta concordancia (88 %), y un índice Kappa (0,72). Conclusiones: Ambas técnicas de cribado molecular isotérmico son adecuadas para el cribado del SARS-CoV-2, con una sensibilidad y especificidad similares.

A Critical Analysis of the Automated Hematology Assessment in Pregnant Women at Low and at High Altitude: Association between Red Blood Cells, Platelet Parameters, and Iron Status.

The objectives of the study were to determine differences in the parameters of red blood cells (RBC), white blood cells (WBC), and platelets at low altitude (LA) and at high altitude (HA) and with the gestation being advanced, and to determine correlations between parameters of RBC and platelets. We also studied the association of RBC and platelets with markers of iron status. In addition, markers of iron status and inflammation were measured and compared at each trimester of gestation in pregnant women at LA and HA. A cross-sectional comparative study was conducted at Lima (150 m above sea level) and Cusco at 3400 m above sea level from May to December 2019. Hematological parameters in pregnant women (233 at LA and 211 at HA) were analyzed using an automated hematology analyzer. Serum ferritin levels, soluble transferrin receptor (sTfR), hepcidin, erythropoietin, testosterone, estradiol, and interleukin-6 (IL6) levels were measured by ELISA. One-way ANOVA supplemented with post hoc test, chi-square test, and Pearson correlation test statistical analyses were performed. p < 0.05 was considered significant. Pregnant woman at HA compared to LA had significantly lower WBC (p < 0.01), associated with higher parameters of the RBC, except for the mean corpuscular volume (MCV) that was no different (p > 0.05). Platelets and mean platelet volume (MPV) were higher (p < 0.01), and platelet distribution width (PDW) was lower at HA than at LA (p < 0.01). A higher value of serum ferritin (p < 0.01), testosterone (p < 0.05), and hepcidin (p < 0.01) was observed at HA, while the concentration of sTfR was lower at HA than at LA (p < 0.01). At LA, neutrophils increased in the third trimester (p < 0.05). RBC parameters decreased with the progress of the gestation, except RDW-CV, which increased. The platelet count decreased and the MPV and PDW were significantly higher in the third trimester. Serum ferritin, hepcidin, and serum testosterone decreased, while sTfR and serum estradiol increased during gestation. At HA, the WBC and red blood cell distribution width- coefficient of variation (RDW-CV), PCT, and serum IL-6 did not change with gestational trimesters. RBC, hemoglobin (Hb), hematocrit (Hct), mean corpuscular hemoglobin concentration (MCHC), and platelet count were lower as gestation advanced. MCV, MPV, and PDW increased in the third trimester. Serum ferritin, testosterone, and hepcidin were lower in the third trimester. Serum estradiol, erythropoietin, and sTfR increased as gestation progressed. Direct or inverse correlations were observed between RBC and platelet parameters and LA and HA. A better number of significant correlations were observed at HA. Hb, Hct, and RDW-CV showed a significant correlation with serum ferritin at LA and HA. Of these parameters, RDW-CV and PDW showed an inversely significant association with ferritin (p < 0.05). In conclusion, a different pattern was observed in hematological markers as well as in iron status markers between pregnant women at LA and HA. In pregnant women a significant correlation between several RBC parameters with platelet marker parameters was also observed. Data suggest that pregnant women at HA have adequate iron status during pregnancy as reflected by higher serum ferritin levels, lower sTfR levels, and higher hepcidin values than pregnant women at LA.

Ingesta de dióxido de cloro para la COVID-19

Durante muchos años, el dióxido de cloro ha sido utilizado por su principal característica como desinfectante, abarcando diversas áreas de aplicación como la sanitaria, alimenticia, industrial, etc. La evidencia reportada hasta la fecha cita diversos estudios en modelos animales, desde revisiones sobre la toxicocinética hasta la aplicación o usos del compuesto. Su poder como bactericida, virucida y eliminador microbiológico lo convirtió en una fuente de control y potabilización de aguas. La controversia generada actualmente es sobre el uso de este compuesto para el tratamiento y control de la COVID-19. Se ha evidenciado incongruencia con algunos resultados reportados y que su aplicación en pacientes positivos a SARS-CoV-2 o para prevenir COVID-19 puede tener efectos adversos, como un acrecentado número de intoxicaciones y, en otros casos, la muerte. En la presente revisión se detalla, a partir de la evidencia científica reportada, los efectos de este compuesto sobre la salud y la interacción con el virus SARS-CoV-2.

Anemias nutricionales de la infancia / Nutritional anemias of childhood

La presente publicación describe los temas que pueden permitir explicar, en base a evidencias científicas, las razones de la baja respuesta a las intervenciones con suplementos de hierro y que van más allá de una explicación basada solo en la falta de adherencia al consumo de hierro. La deficiencia de hierro, con o sin anemia, es un problema mundial que afecta a millones de personas, sobre todo a mujeres y niños. En países en desarrollo, principalmente debido a la pobre ingesta y/o a parasitosis y, en países desarrollados, debido a pérdida de sangre crónica, dietas vegetarianas condicionantes o pobre absorción de hierro por mecanismos patológicos asociados. El diagnóstico actual del estado deficitario de hierro es relativamente simple salvo en condiciones de deficiencia funcional de hierro asociada a procesos inflamatorios crónicos. Hemos hecho una revisión del metabolismo del hierro desde su ingreso al tracto digestivo, su absorción y transporte en el enterocito, su liberación al polo vascular y su unión a la transferrina y la acción de la hormona hepática hepcidina, el más importante regulador de la absorción del hierro intestinal y finalmente la forma en que el hierro se deposita como reserva en forma de ferritina. Las sales de hierro por vía oral son las más usadas para tratar esta deficiencia absorbiéndose bastante bien cuando hay un bajo nivel de hepcidina. Lamentablemente muchos pacientes no lo toleran bien y no completan el tratamiento impidiéndose una adecuada recuperación de los niveles de hemoglobina y reserva de hierro. El uso de hierro endovenoso viene siendo usado cada vez más, puesto que permite en pocas infusiones restablecer el depósito de hierro y elevar el nivel de hemoglobina de los pacientes más rápidamente que con la forma oral, siendo también de utilidad en casos de deficiencia funcional de hierro asociada a procesos inflamatorios crónicos

Total Urinary Arsenic and Inorganic Arsenic Concentrations and Birth Outcomes in Pregnant Women of Tacna, Peru: A Cross-Sectional Study.

Inorganic arsenic exposure has been linked to the development of several health conditions, including adverse birth outcomes; and around 150 million of people worldwide are exposed to levels above the WHO suggested limit of 10 µg/L. A recent risk assessment in pregnant women of Tacna, of this same population performed by our group, found that 70.25% were exposed to arsenic concentrations in drinking water ≥25 µg/L. The present study aimed to evaluate the relationship between prenatal total urinary arsenic (U-tAs) and inorganic arsenic (U-iAs) with adverse birth outcomes. A total of 147 pregnant women from the province of Tacna, Peru, during February - March, 2019, were evaluated for U-tAs and U-iAs exposure during their second trimester of pregnancy, while the birth records of their children were collected from the local hospital. The geometric mean U-tAs was 43.97 ± 25.88 µg/L (P50 22.30, range 5.99 - 181.94 µg/L) and U-iAs was 5.27 ± 2.91 µg/L. Controlling for maternal age, pre-pregnancy BMI, parity, mother's education and newborn sex, no relationship was observed between tertile of U-tAs and the birth outcomes considered, although we found an apparent but statistically non-significant dose-response relationship for small-for-gestational-age 2.38% ( 95% CI 0.003, 0.16), versus 7.32% (95% CI 0.02, 0.21%), versus 8.57% (0.03, 0.25%). This finding requires further evaluation considering other factors such as metabolic arsenic species, additional maternal covariates and ethnicity.

Changes in hemoglobin levels with age and altitude in preschool-aged children in Peru: the assessment of two individual-based national databases.

According to the World Health Organization, the cutoff hemoglobin (Hb) value for defining anemia is 11 g/dL in preschool-aged children, and Hb measurements should be corrected above an altitude of 1000 meters. This study sought to determine the altitude at which the Hb value increases compared with that at sea level, Hb changes with age and region in Peru, the prevalence of anemia according to three different models used to correct Hb for altitude, and the association of the Hb value with stunting. Two individual-based Peruvian national databases were analyzed. Hb increased from an altitude of 375 meters. Hb concentration was lower at younger ages and higher at older ages. The increase in Hb with increasing altitude was lower in southern Peru. Implementing the different models for Hb measurement correction resulted in a higher and lower prevalence of anemia at altitudes >2500 and <2500 m, respectively, using the CDC adjustment. In children aged 6-23 months, the rate of stunting was lower in those with an Hb level of 10-12 g/dL (including mild anemia). In conclusion, the adjustment of Hb values for altitude should be considered before 1000 m and reference ranges should be adjusted to smaller groups of children instead of the same reference range for children aged 6-59 months.

Arsenic Concentrations in Household Drinking Water: A Cross-Sectional Survey of Pregnant Women in Tacna, Peru, 2019.

The World Health Organization (WHO) estimates that around ~150 million people in 70 different countries have been consuming water with arsenic levels higher than the recommended limit of 10 µg/L. Here we describe the concentrations of inorganic arsenic in drinking water in homes of pregnant women living in the province of Tacna, near the southern border of Peru. 161 pregnant women were enrolled in their second trimester of pregnancy. A total of 100mL drinking water was collected in each household from the source of most common use. Inorganic arsenic was categorized into 3 levels with a commercial kit. Thirty percent of women had drinking water ≤10 µg/L (the WHO recommended level), 35% had 25 µg/L, and 35% had greater than 50 µg/L. Low arsenic levels were found in the southernmost homes, supplied by groundwater, while high levels were found in the northern and metropolitan homes supplied by river water.

Inflammatory pathway employed by Red Maca to treat induced benign prostatic hyperplasia in rats.

Benign prostatic hyperplasia (BPH) is a pathology characterised by an increase in prostate size associated with low urinary tract symptoms. Finasteride (F), a 5a-reductase inhibitor, is the standard treatment for BPH reducing prostate weight but also sexual desire. The Peruvian plant known as Red Maca (RM) (Lepidium meyenii) inhibits BPH in rats and mice. The aim of the study was to assess the inflammatory effect of RM and finasteride in rats with testosterone enanthate (TE)-induced BPH. Thirty rats were divided into 5 groups: Control, TE (50 mg/rat), TE + F (0.6 mg/kg), and two groups of TE + RM 40/80 (40 or 80 mg). After treatments, tumour necrosis factor alpha (TNFa), interleukin 4 (IL4) and interferon gamma (INFg) as well as testosterone and oestradiol were evaluated and inflammatory cells (neutrophils, mast cells and lymphocytes) in prostate were quantified. Red Maca and finasteride treatments decreased inflammatory cells counts in prostate, inhibiting TNFa by different pathways. Finasteride increased IL4 whereas Red Maca increased INFg. In conclusion, data suggest that finasteride acts on Th2 response by increasing IL4 in prostate, while Red Maca acts on Th1 response mediated by INFg.

Situación mundial de la anemia en gestantes / No disponible

No disponible

[Traffic regulation and environmental pollution by particulate material (2.5 and 10), sulfur dioxide, and nitrogen dioxide in Metropolitan Lima, Peru]. / Reordenamiento vehicular y contaminación ambiental por material particulado (2,5 y 10), dióxido de azufre y dióxido de nitrógeno en Lima Metropolitana, Perú.

OBJECTIVE.: To assess the change in environmental levels of PM2.5, PM10, SO2, and NO2, after the application of a traffic regulation plan in Abancay Avenue between the years 2013-2015 vs. to 2007-2009, and comparing it against two other avenues, in which no traffic regulation was implemented: Guillermo de La Fuente Avenue in the district of Comas and Cesar Vallejo Avenue in El Agustino. MATERIALS AND METHODS.: Environmental data were collected by three air monitors from the Ministry of Health's Environmental Health and Food Safety General Directorate (Dirección General de Salud Ambiental e Inocuidad Alimentaria) that are part of the Air Quality Surveillance network of the city of Lima. The beta coefficient of the linear regression allowed to assess change in the concentration of each pollutant. RESULTS.: The traffic regulation plan of Abancay Av. reduced the levels of PM2.5 by 62%; 55% for PM10 levels; 65% for the NO2 levels, and 82% for the SO2 levels. In the other two avenues assess, this reduction was not observed. A significant reduction in PM2.5 (ß: -53.11 µg/m3; 95% CI: -63.92 to -42.30), PM10 (ß: -47.99 µg/m3; 95% CI: -62.61 to -33.37), NO2 (ß: -41.71 µg/m3; 95% CI: -48.18 to -35.23), and SO2 (ß: -28.59 µg/m3; 95% CI: -35.23 to -21.95) was observed in Abancay Av., with respect to the other two avenues, after the traffic regulation plan was implemented. CONCLUSIONS.: Traffic regulation can contribute to the continuous reduction of different air pollutants. The expansion of this measure could improve air quality and the health status of the residents of Lima.

OBJETIVOS.: Evaluar el cambio en los niveles ambientales de material particulado (2,5 y 10) (PM2,5 y PM10), dióxido de azufre (SO2) y dióxido de nitrógeno (NO2), posterior al reordenamiento vehicular en la avenida Abancay, entre 2013-2015 respecto a 2007-2009, comparando con otras dos avenidas sin implementación de un reordenamiento, la avenida Guillermo de La Fuente en el distrito de Comas y la avenida César Vallejo en el distrito de El Agustino. MATERIALES Y MÉTODOS.: Los datos ambientales fueron colectados por tres monitores de Dirección General de Salud Ambiental e Inocuidad Alimentaria del Ministerio de Salud como parte de la red de Vigilancia de la calidad del aire de la ciudad de Lima. El coeficiente beta de la regresión lineal permitió evaluar el cambio en la concentración de cada contaminante. RESULTADOS.: El reordenamiento de la Av. Abancay redujo 62% los niveles de PM2,5; 55% los niveles de PM10; 65% los niveles NO2; y 82% los de SO2. En las otras dos avenidas evaluadas no se observó disminución. Una reducción significativa de PM 2,5 (ß: -53,11 µg/m3; IC 95%: -63,92 a -42,30), PM10 (ß: -47,95 µg/m3; IC 95%: -62,61 a -33,37), NO2 (ß:-41,71 µg/m3, IC 95%: -48,18 a -35,23) y SO2 (ß: -28,59 µg/m3; IC 95%: -35,23 a -21,95) fueron observados en la Av. Abancay, respecto a las otras dos avenidas, posterior al reordenamiento vehicular. CONCLUSIONES.: El reordenamiento vehicular puede contribuir con la disminución continua de diversos contaminantes ambientales. La extensión de esta medida podría mejoraría la calidad de aire y estado de salud de la población residente en la ciudad de Lima.

Reordenamiento vehicular y contaminación ambiental por material particulado (2,5 y 10), dióxido de azufre y dióxido de nitrógeno en Lima Metropolitana, Perú / Traffic regulation and environmental pollution by particulate material (2.5 and 10), sulfur dioxide, and nitrogen dioxide in Metropolitan Lima, Peru

RESUMEN Objetivos. Evaluar el cambio en los niveles ambientales de material particulado (2,5 y 10) (PM2,5 y PM10), dióxido de azufre (SO2) y dióxido de nitrógeno (NO2), posterior al reordenamiento vehicular en la avenida Abancay, entre 2013-2015 respecto a 2007-2009, comparando con otras dos avenidas sin implementación de un reordenamiento, la avenida Guillermo de La Fuente en el distrito de Comas y la avenida César Vallejo en el distrito de El Agustino. Materiales y métodos. Los datos ambientales fueron colectados por tres monitores de Dirección General de Salud Ambiental e Inocuidad Alimentaria del Ministerio de Salud como parte de la red de Vigilancia de la calidad del aire de la ciudad de Lima. El coeficiente beta de la regresión lineal permitió evaluar el cambio en la concentración de cada contaminante. Resultados. El reordenamiento de la Av. Abancay redujo 62% los niveles de PM2,5; 55% los niveles de PM10; 65% los niveles NO2; y 82% los de SO2. En las otras dos avenidas evaluadas no se observó disminución. Una reducción significativa de PM 2,5 (β: -53,11 μg/m3; IC 95%: -63,92 a -42,30), PM10 (β: -47,95 μg/m3; IC 95%: -62,61 a -33,37), NO2 (β:-41,71 μg/m3, IC 95%: -48,18 a -35,23) y SO2 (β: -28,59 μg/m3; IC 95%: -35,23 a -21,95) fueron observados en la Av. Abancay, respecto a las otras dos avenidas, posterior al reordenamiento vehicular. Conclusiones. El reordenamiento vehicular puede contribuir con la disminución continua de diversos contaminantes ambientales. La extensión de esta medida podría mejoraría la calidad de aire y estado de salud de la población residente en la ciudad de Lima.

Objective. To assess the change in environmental levels of PM2.5, PM10, SO2, and NO2, after the application of a traffic regulation plan in Abancay Avenue between the years 2013-2015 vs. to 2007-2009, and comparing it against two other avenues, in which no traffic regulation was implemented: Guillermo de La Fuente Avenue in the district of Comas and Cesar Vallejo Avenue in El Agustino. Materials and Methods. Environmental data were collected by three air monitors from the Ministry of Health's Environmental Health and Food Safety General Directorate (Dirección General de Salud Ambiental e Inocuidad Alimentaria) that are part of the Air Quality Surveillance network of the city of Lima. The beta coefficient of the linear regression allowed to assess change in the concentration of each pollutant. Results. The traffic regulation plan of Abancay Av. reduced the levels of PM2.5 by 62%; 55% for PM10 levels; 65% for the NO2 levels, and 82% for the SO2 levels. In the other two avenues assess, this reduction was not observed. A significant reduction in PM2.5 (β: -53.11 μg/m3; 95% CI: -63.92 to -42.30), PM10 (β: -47.99 μg/m3; 95% CI: -62.61 to -33.37), NO2 (β: -41.71 μg/m3; 95% CI: -48.18 to -35.23), and SO2 (β: -28.59 μg/m3; 95% CI: -35.23 to -21.95) was observed in Abancay Av., with respect to the other two avenues, after the traffic regulation plan was implemented. Conclusions. Traffic regulation can contribute to the continuous reduction of different air pollutants. The expansion of this measure could improve air quality and the health status of the residents of Lima.

Necesidades de investigación para el diagnóstico de anemia en poblaciones de altura / Diagnosis of anemia in populations at high altitudes

Tanto la deficiencia como la sobrecarga de hierro son situaciones que ponen en riesgo la salud y la vida de las personas, por lo que es importante mantener su homeostasis. Como la hemoglobina contiene 70% del hierro del organismo, la OMS recomienda su medición para determinar la prevalencia de anemia por deficiencia de hierro (ID), a pesar que ellos mismos reconocen que la anemia no es específica de ID. Como la hemoglobina aumenta con la altitud de residencia, la OMS recomienda corregir el punto de corte para definir anemia en la altura. Una objeción a esta corrección es que el aumento de la hemoglobina en la altura no es universal ni aumenta de manera lineal. Además, las poblaciones de mayor antigüedad generacional tienen menos hemoglobina que las más recientes. En infantes, niños, gestantes y adultos, la prevalencia de anemia usando hemoglobina corregida es 3-5 veces mayor que usando marcadores del estatus de hierro. Los programas estatales buscan combatir la anemia mediante la suplementación de hierro; no obstante, resultan ineficaces, especialmente en las poblaciones de altura. Entonces, ¿hay deficiencia de hierro en la altura? Los niveles de hepcidina sérica, hormona que regula la disponibilidad de hierro, son similares a los de nivel del mar indicando que en la altura no hay deficiencia de hierro. Un problema adicional al corregir la hemoglobina por la altura, es que las prevalencias de eritrocitosis disminuyen. En conclusión, la corrección del punto de corte de la hemoglobina en la altura para determinar deficiencia de hierro es inadecuada.

Iron deficiency and overload are risk factors for numerous poor health outcomes, and thus the maintenance of iron homeostasis is vital. Considering that hemoglobin contains 70% of the total iron in the body, the World Health Organization (WHO) recommends the measurement of iron levels to calculate the rate of iron deficiency anemia (IDA), although WHO recognizes that IDA is not the only cause of anemia. As hemoglobin increases with altitude, WHO recommends correcting the cut-off point to define anemia at high altitudes. An objection to this correction is that the increase in hemoglobin at high altitudes is not universal and is not linear. In addition, individuals in older age groups have lower hemoglobin levels than those in younger age groups. In infants, children, pregnant women, and adults, the prevalence of anemia using corrected hemoglobin is 3-5 times higher than that using markers of iron status. State programs seek to control anemia by means of iron supplementation. However, these programs are ineffective, particularly for high-altitude populations. Therefore, the occurrence of iron deficiency at high altitudes is controversial. The serum levels of the hormone hepcidin, which regulates iron availability, are similar in individuals at high altitudes to those of individuals at sea level, indicating that iron deficiency does not occur at high altitudes. An additional problem when correcting hemoglobin at high altitudes is that the frequency of erythrocytosis is decreased. In conclusion, the correction of the cut-off point of hemoglobin at high altitudes to determine iron deficiency is inadequate.