High-altitude is associated with better short-term survival in critically ill COVID-19 patients admitted to the ICU

  1. Katherine Simbaña-Rivera
  2. Pablo R. Morocho Jaramillo
  3. Javier V. Velastegui Silva
  4. Lenin Gómez-Barreno
  5. Ana B. Ventimilla Campoverde
  6. Juan F. Novillo Cevallos
  7. Washington E. Almache Guanoquiza
  8. Silvio L. Cedeño Guevara
  9. Luis G. Imba Castro
  10. Nelson A. Moran Puerta
  11. Alex W. Guayta Valladares
  12. Alex Lister
  13. Esteban Ortiz-Prado

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Abstract

Multiple studies have attempted to elucidate the relationship between chronic hypoxia and SARS-CoV-2 infection. It seems that high-altitude is associated with lower COVID-19 related mortality and incidence rates; nevertheless, all the data came from observational studies, being this the first one looking into prospectively collected clinical data from severely ill patients residing at two significantly different altitudes.

Methods

A prospective cohort, a two-center study among COVID-19 confirmed adult patients admitted to a low (sea level) and high-altitude (2,850 m) ICU unit in Ecuador was conducted. Two hundred and thirty confirmed patients were enrolled from March 15 th to July 15 th , 2020.

Results

From 230 patients, 149 were men (64.8%) and 81 women (35.2%). The median age of all the patients was 60 years, and at least 105 (45.7%) of patients had at least one underlying comorbidity, including hypertension (33.5%), diabetes (16.5%), and chronic kidney failure (5.7%). The APACHE II scale (Score that estimates ICU mortality) at 72 hours was especially higher in the low altitude group with a median of 18 points (IQR: 9.5–24.0), compared to 9 points (IQR: 5.0–22.0) obtained in the high-altitude group. There is evidence of a difference in survival in favor of the high-altitude group (p = 0.006), the median survival being 39 days, compared to 21 days in the low altitude group.

Conclusion

There has been a substantial improvement in survival amongst people admitted to the high-altitude ICU. Residing at high-altitudes was associated with improved survival, especially among patients with no comorbidities. COVID-19 patients admitted to the high-altitude ICU unit have improved severity-of-disease classification system scores at 72 hours.

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  1. Version published to 10.1371/journal.pone.0262423
  2. ScreenIT

    SciScore for 10.1101/2021.01.22.21249811: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board StatementConsent: Inclusion criteria: Adult men and women patients admitted to the ICU diagnosed with COVID-19 by means of RT-PCR who lived at least 1 year in the unit’s coverage region and signed the informed consent for the use of the information were included in this study.
    Randomizationnot detected.
    BlindingBias: In order to minimize observation bias for systematic differences between the low and high-altitude group, observers were blinded the hypothesis under investigation and a strict protocol was implemented in both sites.
    Power Analysisnot detected.
    Sex as a biological variableInclusion criteria: Adult men and women patients admitted to the ICU diagnosed with COVID-19 by means of RT-PCR who lived at least 1 year in the unit’s coverage region and signed the informed consent for the use of the information were included in this study.

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    All statistical analyzes were performed in SPSS version 25 and graphs were generated using GraphPad Prism version 7.00 software (GraphPad Software Inc).
    SPSS
    suggested: (SPSS, RRID:SCR_002865)
    GraphPad Prism
    suggested: (GraphPad Prism, RRID:SCR_002798)
    GraphPad
    suggested: (GraphPad Prism, RRID:SCR_002798)

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: An explicit section about the limitations of the techniques employed in this study was not found. We encourage authors to address study limitations.

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We found bar graphs of continuous data. We recommend replacing bar graphs with more informative graphics, as many different datasets can lead to the same bar graph. The actual data may suggest different conclusions from the summary statistics. For more information, please see Weissgerber et al (2015).

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • No funding statement was detected.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  3. Version published to 10.1101/2021.01.22.21249811v1 on medRxiv