Excessive Erythrocytosis and Chronic Mountain Sickness in Dwellers of the Highest City in the World

Hancco, Iván; Bailly, Sébastien; Baillieul, Sébastien; Doutreleau, Stéphane; Germain, Michèle; Pépin, Jean‐Louis; Vergès, Samuel

doi:10.3389/fphys.2020.00773

Cited by 32 publications

(24 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As shown in this and our previous studies (Hancco et al, 2020;Oberholzer et al, 2020), although consisting of relatively young and active workers, the population of La Rinconada is characterized by a profound and chronic hypoxemia (as reflected by a mean SpO 2 of 80%) and by a high prevalence of EE (which may promote severe complications such as high-altitude pulmonary hypertension and right heart failure, mostly underdiagnosed in a precarious environment with limited health care access). Thereby, we believe that these specific high-altitude comorbidities may represent potential worsening factors when severe COVID-19 occurred, making this population particularly vulnerable in case of critical illness.…”

Section: Covid-19 In the Highest City In The Worldsupporting

confidence: 67%

“…In addition to SARS-CoV-2 testing, hemoglobin concentration ([Hb]) was assessed (Hemocue AB, Angelholm, Sweden). The presence of EE ([Hb] ‡21 g/dl for male and ‡19 g/dl for female) and CMS (based on the [Hb] concentration and the Quinghai CMS symptom score) was reported (Hancco et al, 2020;Oberholzer et al, 2020). Demographic, occupational, and house characteristics, as well as the occurrence of at least one symptom compatible with a COVID-19 illness in the previous 6 months, were recorded (Hu et al, 2020).…”

Section: Methodsmentioning

confidence: 99%

“…La Rinconada, known as the highest city in the world, is a gold-mining town located in the southeastern Peru at an altitude of 5,100-5,300 m where an estimated population of >50,000 dwellers live in precarious sanitary conditions (Enserink, 2019). We recently reported that highlanders permanently living at such an extreme altitude exhibited severe chronic hypoxemia, leading to excessive erythrocytosis (EE) and chronic mountain disease (CMS), a specific high-altitude comorbidity (Hancco et al, 2020;Oberholzer et al, 2020). In contrast to a putative protective effect of high altitude against SARS-CoV-2, crowded and precarious living conditions have been shown to be associated with a high seroprevalence for SARS-CoV-2 (Del Brutto et al, 2020;Roederer et al, 2021).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

High-Altitude Environment and COVID-19: SARS-CoV-2 Seropositivity in the Highest City in the World

Champigneulle

Hancco

Renan

et al. 2021

High Altitude Medicine & Biology

Self Cite

View full text Add to dashboard Cite

Background: A reduced coronavirus disease 2019 (COVID-19) diffusion has been suggested in high-altitude areas but remained questionable. Aims of this study were to estimate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seropositivity as well as the risk factors associated in La Rinconada, the highest city in the world (5,100-5,300 m), a gold-mining town located in southeastern Peru where >50,000 dwellers live in precarious sanitary conditions. Materials and Methods: We performed a cross-sectional study during a 1-week period in October 2020, using point-of-care lateral flow serological assays allowing detection of antibodies directed against SARS-CoV-2 among voluntary dwellers in La Rinconada. Participants were also questioned about potential occupational and environmental risk factors of COVID-19 occurrence. Results: In a sample of 159 dwellers tested in La Rinconada, 48.4% [95% confidence interval, CI: 40.5-56.4] were seropositive for the SARS-CoV-2. Occurrence of at least one symptom compatible with the COVID-19 over the past 6 months remained the only significant factor associated with SARS-CoV-2 seropositivity (adjusted odds ratio: 3.27; [95% CI: 1.70-6.44]; p < 0.001). Conclusions: The high rate of SARS-CoV-2 seropositivity observed in this small sample of highlanders does not support a protective effect of high-altitude against the COVID-19 spread and demonstrates its large dissemination in vulnerable populations. Clinical Trial Registration number: NCT04604249.

show abstract

Section: Covid-19 In the Highest City In The Worldsupporting

confidence: 67%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

High-Altitude Environment and COVID-19: SARS-CoV-2 Seropositivity in the Highest City in the World

Champigneulle

Hancco

Renan

et al. 2021

High Altitude Medicine & Biology

Self Cite

View full text Add to dashboard Cite

show abstract

“…46,47 The Tibetans are known to have a lower prevalence of CMS compared to the Andeans. [48][49][50] Though our participants had a comparatively higher prevalence of CMS, all of them had mild CMS. Though RBC, HCT and hemoglobin were significantly higher in the high altitude Tibetans, interestingly, serum EPO was only insignificantly higher in high altitude individuals; this might be because the normal concentration of serum erythropoietin has an apparently broad range: 3.3-16.6 mIU/mL.…”

Section: Discussionmentioning

confidence: 99%

Heterogeneity in Hematological Parameters of High and Low Altitude Tibetan Populations

Basak¹,

Norboo²,

Mustak³

et al. 2021

JBM

View full text Add to dashboard Cite

Introduction: High altitude hypoxia is believed to be experienced at elevations of more than 2500 meters above sea level. Several studies have shed light on the biochemical aspects of high altitude acclimatization, where participants were sojourners to the high altitude from low altitude areas. However, information regarding the difference between the high altitude adapted Tibetans living at high altitude and their counterparts who reside at low altitude are lacking. To understand this, we have measured various hematological parameters in the Tibetan populations, who are residing in both high and low altitudes in India. Methods: A total of 168 individuals (79 from high altitude (≥4500 meters) and 89 from low altitude (~850 meters) were recruited for this study. Hematological parameters such as red blood cells (RBC) count, hematocrit (HCT), hemoglobin concentration (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) were measured from the individuals from high and low altitudes. Serum erythropoietin (EPO) was measured by ELISA. Statistical analyses were performed to compare data from both of the altitudes. Gender-wise comparison of data was reported. Correlation analysis was performed within relevant parameters. Results: Highly significant differences (p <0.0001) between high and low altitude Tibetans were detected in RBC count, HCT, Hb, MCHC in both males and females and in MCV in females. In the case of MCHC, however, age and BMI were potential confounders. Nominally significant differences (p <0.05) were detected in MCV and MCH within males. No significant difference in serum EPO level was found between altitude groups, in any gender. No significant correlation was found between serum EPO with Hb as well as serum EPO with HCT. Discussion: Our study explores significantly lower RBC count, HCT, Hb, MCH, MCHC and higher MCV in long-term Tibetan residents living at low altitude compared to their high altitude counterparts, which is likely due to the outcome of hematological adaptation to a relatively hyperoxic environment in low altitude areas.

show abstract

“…CMS survey is an important way to acknowledge the prevalence. However, studies in different periods or areas could not be compared properly due to the varied CMS diagnosis methods [1][2][3][4]. In this study, we used Qinghai standard to survey the prevalence of CMS in Chinese Han individuals who migrated to Qinghai-Tibetan plateau at an altitude of 3300-5400 m in 2009 and 2019.…”

Section: Introductionmentioning

confidence: 99%

2009-2019: A comparative study on CMS of plateau migrants around ten years

Gao

Xie

Gao

et al. 2021

Preprint

View full text Add to dashboard Cite

BackgroundChronic mountain sickness (CMS), is a common disease occurred to people who migrate to plateau. Current CMS studies in different periods or areas have poor comparability due to the inconsistent diagnosis methods. Here we carried out a comparative study of the CMS prevalence in the year 2019 and 2009, to provide evidence for the prevention and diagnosis of CMS. Methods The Qinghai CMS Scoring System (Qinghai standard) was used to investigate the subjects who lived for at least months in the 3300-5400 m altitude area in 2019 and 2009, respectively. Their prevalence and symptom scores were also analyzed and statistically compared.ResultsThe prevalence of CMS in 2019 survey subjects (15.60%) was significantly lower than that in 2009 (31.18%). The prevalence of dyspnea, venous dilatation, paresthesia, headache, tinnitus, and hemoglobin concentration reached 21g/dL or above decreased significantly among the survey subjects in 2019. The scores of cyanosis, venous dilatation, paresthesia, and headache significantly decreased in the 2019 survey subjects. But among the CMS patients, the sleep disturbance scores of the 2019 survey subjects increased significantly. ConclusionCompared to 2009, the health level of high altitude living population in 2019 has been significantly improved, indicating that the sleep research on high-altitude living population and the application of high altitude oxygen therapy has been effective in the past ten years. Among the CMS associated symptoms, sleep disturbance is an important indicator for the prevention and diagnosis of CMS, which deserves special attention.

show abstract

Excessive Erythrocytosis and Chronic Mountain Sickness in Dwellers of the Highest City in the World

Cited by 32 publications

References 33 publications

High-Altitude Environment and COVID-19: SARS-CoV-2 Seropositivity in the Highest City in the World

High-Altitude Environment and COVID-19: SARS-CoV-2 Seropositivity in the Highest City in the World

Heterogeneity in Hematological Parameters of High and Low Altitude Tibetan Populations

2009-2019: A comparative study on CMS of plateau migrants around ten years

Contact Info

Product

Resources

About