The effects of hypertension as an existing comorbidity on mortality rate in patients with COVID-19 A systematic review and meta-analysis

  1. Elena Whiteman

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Abstract

Introduction

Coronavirus has spread throughout the world rapidly, and there is a growing need to identify host risk factors to identify those most at risk. There is a growing body of evidence suggesting a close link exists between an increased risk of infection and an increased severity of lung injury and mortality, in patients infected with COVID-19 who have existing hypertension. This is thought to be due to the possible involvement of the virus target receptor, ACE2, in the renin-angiotensin-aldosterone blood pressure management system.

Objective

To investigate the association between hypertension as an existing comorbidity and mortality in hospitalized patients with confirmed coronavirus disease 2019 (COVID-19).

Methods

A systematic literature search in several databases was performed to identify studies that comment on hypertension as an existing comorbidity, and its effect on mortality in hospitalized patients with confirmed COVID-19 infection. The results of these studies were then pooled, and a meta-analysis was peformed to assess the overall effect of hypertension as an existing comorbidity on risk of mortality in hospitalized COVID-19 positive patients.

Results

A total of 12243 hospitalised patients were pooled from 19 studies. All studies demonstrated a higher fatality rate in hypertensive COVID-19 patients when compared to non-hypertensive patients. Meta-analysis of the pooled studies also demonstrated that hypertension was associated with increased mortality in hospitalized patients with confirmed COVID-19 infection (risk ratio (RR) 2.57 (95% confidence interval (CI) 2.10, 3.14), p < 0.001; I 2 =74.98%).

Conclusion

Hypertension is associated with 157% increased risk of mortality in hospitalized COVID-19 positive patients. These results have not been adjusted for age, and a meta-regression of covariates including age is required to make these findings more conclusive.

Summary

Risk of mortality is considerably higher in hospitalised COVID-19 patients who have hypertension as an existing comorbidity prior to admission.

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  1. ScreenIT

    SciScore for 10.1101/2020.11.16.20149377: (What is this?)

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

    Table 1: Rigor

    Institutional Review Board Statementnot detected.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.
    Sex as a biological variablenot detected.

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    We used STATA (StataCorp. 2019. Stata Statistical
    STATA
    suggested: (Stata, RRID:SCR_012763)
    StataCorp
    suggested: (Stata, RRID:SCR_012763)

    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: We detected the following sentences addressing limitations in the study:
    Limitations and strengths: This meta-analysis does demonstrate a significantly increased risk of mortality in hypertensive COVID-19 patients admitted to hospital; however, only 12243 patients were included. To date, there have been 8,577,196 reported cases of COVID-19 worldwide and so this sample is not largely representative, and a much larger sample of patients would be needed to make these findings conclusive. The reason for such a small sample of inclusion, at least at present, is the lack of studies due to the novel nature of this disease; as time progresses, I expect there to be many more studies eligible for inclusion in a similar systematic review in future. A large level of heterogeneity between studies was also present, and this is likely to be due to confounding factors which were not controlled for in the studies. These factors can include smoking status, ethnicity, additional comorbidities, amongst others. There may also be significant discrepancies in how data was collected across all studies, as the studies included fail to define how ‘existing hypertension’ was classified. The follow-up period is also very limited, again owing to the novel nature of this disease, and therefore the mortality figures may be skewed; a longer follow up period would be preferred to allow a bigger catchment time to assess mortality in patients who were only recently admitted at the time of writing. Finally, COVID-19 is a worldwide pandemic but the included studies are not descriptiv...

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    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.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

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  2. Version published to 10.1101/2020.11.16.20149377v1 on medRxiv