Greater Covid-19 Severity and Mortality in Hospitalized Patients in Second (Delta Variant) Wave Compared to the First: Single Centre Prospective Study in India

  1. Raghubir S Khedar
  2. Kartik Mittal
  3. Harshad C Ambaliya
  4. Alok Mathur
  5. Jugal B Gupta
  6. Krishna K Sharma
  7. Yogendra Singh
  8. Gunjan Sharma
  9. Akhil Gupta
  10. Vaibhav Bhargava
  11. Kishore Mangal
  12. Anil K Sharma
  13. Yatendra K Gupta
  14. Pramod Sarwa
  15. Bhawani S Mishra
  16. Swati Sharma
  17. Krishnakumar Sharma
  18. Rajeev Gupta

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Abstract

Background & Objective

Covid-19 pandemic has led to multiple waves secondary to mutations in SARS-CoV-2 and emergence of variants of concern (VOC). Clinical characteristics of delta (B.1.617.2) VOC are not well reported. To compare demographic, clinical and laboratory features and outcomes in the second Covid-19 wave in India (delta VOC) with the previous wave we performed a registry-based study.

Methods

Successive SARS-CoV-2 reverse transcriptase-polymerase chain reaction (RT-PCR) confirmed Covid-19 patients presenting to our Advanced Covid Care hospital were prospectively recruited. In the first phase (wave) from March-December 2020, 1395 of 7476 (18.7%) suspected patients tested positive and 863 (61.89%) hospitalized, while in second wave from January-July 2021 out of 1641 confirmed cases out of 8680 (19.4%) suspected 388 (23.6%) were hospitalized. Details of clinical and laboratory features at admission to hospital, management and outcomes in the two waves have been compared.

Results

In both cohorts, majority were men and 20% less than 40 years. Prevalence of hypertension, diabetes and cardiovascular diseases was more than 20%. Second wave patients had similar pre-hospitalization symptom duration but had significantly greater cough, fever and shortness of breath and lower SpO 2 at presentation with greater lymphopenia, C-reactive proteins, interleukin-6, ferritin, lactic dehydrogenase and transaminases. In the second vs first wave patients, requirement of supplementary oxygen (47.9% vs 34.3%), prone positioning (89.2 vs 38.6%), high flow nasal oxygen(15.7 vs 9.1%), non-invasive ventilation (14.4 vs 9.5%), invasive ventilation (16.2 vs 9.5%), steroids (94.1 vs 85.9%), remdesivir (91.2 vs 76.0%) and anticoagulants (94.3 vs 76.0%) was greater (p<0.001). Median (IQR) length of stay [8 (6-10) vs 7 (5-10) days] as well as ICU stay [9 (5-13) vs 6 (2-10) days] was more in second wave (p<0.001). In-hospital deaths occurred in 173 patients (13.9%) and were significantly more in the second wave, 75 (19.3%), compared to the first, 98 (11.5%); unadjusted odds ratio (95% CI) 1.84 (1.32-2.55) which did not change significantly with adjustment for age and sex (2.03, 1.44-2.86), and age, sex and comorbidities (2.09, 1.47-2.95). Greater disease severity at presentation was associated with mortality in both the waves.

Conclusions

Covid-19 patients hospitalized during the second wave of the epidemic (delta variant) had more severe disease with greater dyspnea, hypoxia, hematological and biochemical abnormalities compared to first wave patients. They had greater length of stay in intensive care unit, oxygen requirement, non-invasive and invasive ventilatory support. The in-hospital mortality in the second wave was double of the first.

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  1. ScreenIT

    SciScore for 10.1101/2021.09.03.21263091: (What is this?)

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

    Table 1: Rigor

    EthicsIRB: The registry protocol was approved by the institutional ethics committee (Government of India registration, CDSCO No. ECR/615/Inst/RJ/2014/RR-20).
    Consent: Informed consent from all the patients or next-of-kin was obtained for anonymized data publication as permitted by the ethics committee.
    Sex as a biological variablenot detected.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    Descriptive analyses have been performed using SPSS package (Version 21.0).
    SPSS
    suggested: (SPSS, RRID:SCR_002865)

    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:
    This is a study limitation and should be studied in prospective studies. There are only limited studies from India and other countries which compared clinical features and outcomes among the patients in the first and delta VOC waves. Modelling studies predicted lower mortality from the delta variant compared to the earlier VOC’s in India.21,21 Multisite Indian Council of Medical Research study,23 compared clinical characteristics and outcomes of patients in first (September 2020 to January 2021, n=12,059) and the second (February to May 2021, n=6903) waves in a nationwide multisite hospital-based observational study. The study reported greater oxygen requirement, non-invasive and invasive ventilatory support, and higher mortality (13.3% vs 10.2%, unadjusted OR 1.35, CI 1.19-1.52) among patients in the second compares to the first wave. Although clinical details were provided, which are similar to the present study, no biochemical data were published. Budhiraja et al,24 compared clinical characteristics and outcomes in hospitalized Covid-19 patients in a north Indian corporate chain of hospitals (n=10) in the first (n=14,398) and second (n=5454) waves. In the second wave, more patients had evidence of biomarker abnormalities and oxygen and ventilatory support although duration of hospitalization was shorter. Greater mortality was reported in the second vs first wave (10.5% vs 7.2%, +45.8%). A study in Gujarat reported similar mortality due to Covid-19 among renal transplant re...

    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.

    Results from scite Reference Check: We found no unreliable references.

    About SciScore

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  2. Version published to 10.1101/2021.09.03.21263091v1 on medRxiv