ArticleHemaSphere2023
The Increase in Hemoglobin Concentration With Altitude Differs Between World Regions and Is Less in Children Than in Adults.
Article in HemaSphere, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers.
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Who cites it
13 citing papers in PubMed, 19 citations in OpenAlex.
- Altitude thresholds for hemoglobin and plasma volume regulation in adult residents of different altitudes and their impact on hemoglobin concentration.Physiological reports · 2026Article
- Higher Prevalence of Cognitive Impairment in Residents of High-Altitude Regions.Oxygen (Basel, Switzerland) · 2026Article
- Resting and Physical Activity Energy Expenditure Across an Altitudinal Gradient: An Adjusted Analysis.Oxygen (Basel, Switzerland) · 2026Article
- Prevalence, spatial distribution, and determinants of anemia among under-five children in the Democratic Republic of Congo: evidence from the 2023-24 DHS.International journal of health geographics · 2026Article
- Comparison of Red Blood Cell Features in Israeli Circassians: The Possible Effect of Residential Altitude.Rambam Maimonides medical journal · 2026Article
- Demographics, clinical features, and comorbidities of high-altitude polycythaemia: a multicentre, retrospective, observational study.Journal of global health · 2026Observational
- Observational
- Addressing Anemia in High-Altitude Populations: Global Impact, Prevalence, Challenges, and Potential Solutions.American journal of hematology · 2025Review
- Association of hemoglobin with decreased prevalence of diabetic retinopathy among Tibetan male patients.Scientific reports · 2025Article
- Association of hemoglobin variation and hospital mortality in patients with traumatic brain injury at high altitude.Frontiers in neurology · 2025Article
- Establishment of reference intervals for complete blood count in healthy adults at different altitudes on the Western Sichuan Plateau.Frontiers in medicine · 2025Article
- Article
- The Imperative of Population-Specific Biochemical Reference Intervals: A Translational Framework for Precision Public Health.Indian journal of community medicine : official publication of Indian Association of Preventive & Social MedicineArticle
Corrections and comments
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Authors and funding
6 authors at 5 institutions in 4 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
To compensate for decreased oxygen partial pressure, high-altitude residents increase hemoglobin concentrations [Hb]. The elevation varies between world regions, posing problems in defining cutoff values for anemia or polycythemia. The currently used altitude adjustments (World Health Organization [WHO]), however, do not account for regional differences. Data from The Demographic and Health Survey (DHS) Program were analyzed from 32 countries harboring >4% of residents at altitudes above 1000 m. [Hb]-increase, (ΔHb/km altitude) was calculated by linear regression analysis. Tables show 95% reference intervals (RIs) for different altitude ranges, world regions, and age groups. The prevalence of anemia and polycythemia was calculated using regressions in comparison to WHO adjustments. The most pronounced Δ[Hb]/km was found in East Africans and South Americans while [Hb] increased least in South/South-East Asia. In African regions and Middle East, [Hb] was decreased in some altitude regions showing inconsistent changes in different age groups. Of note, in all regions, the Δ[Hb]/km was lower in children than in adults, and in the Middle East, it was even negative. Overall, the Δ[Hb]/km from our analysis differed from the region-independent adjustments currently suggested by the WHO resulting in a lower anemia prevalence at very high altitudes. The distinct patterns of Δ[Hb] with altitude in residents from different world regions imply that one single, region-independent correction factor for altitude is not be applicable for diagnosing abnormal [Hb]. Therefore, we provide regression coefficients and reference-tables that are specific for world regions and altitude ranges to improve diagnosing abnormal [Hb].
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.