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Preprint: Lower prevalence of Post-Covid-19 Condition following Omicron SARS-CoV-2 infection 2023 De Bruijn, Knoop et al

Discussion in 'Long Covid research' started by Andy, Apr 6, 2023.

  1. Andy

    Andy Committee Member

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    Hampshire, UK
    Background: Different SARS-CoV-2 variants can differentially affect the prevalence of Post Covid-19 Condition (PCC). This prospective study assesses prevalence and severity of symptoms three months after an Omicron infection, compared to Delta, test-negative and population controls. This study also assesses symptomology after reinfection and breakthrough infections .

    Methods: After a positive SARS-CoV-2 test, cases were classified as Omicron or Delta based on ≥ 85% surveillance prevalence. Population controls were representatively invited and symptomatic test-negative controls enrolled after a negative SARS-CoV-2 test. Three months after enrolment, participants indicated point prevalence for 41 symptoms and severity of four symptoms. Permutation tests identified significantly elevated symptoms in cases compared to controls. PCC prevalence was estimated as the difference in prevalence of at least one elevated symptom in cases compared to population controls.

    Findings: At three months follow-up, five symptoms and severe dyspnea were significantly elevated in Omicron cases (n = 4138) compared to test-negative (n= 1672) and population controls (n= 2762). PCC prevalence was 10.4% for Omicron cases and 17.7% for Delta cases (n = 6855). Prevalence of severe fatigue and dyspnea were higher in reinfected compared to primary infected Omicron cases, while severity of symptoms did not significantly differ between Omicron cases with a booster or primary vaccination course.

    Interpretation: Three months after Omicron, prevalence of PCC is 41% lower than after Delta. Reinfection seems associated with more prevalent severe long-term symptoms compared to a first infection. A booster prior to infection does not seem to improve the outcome of long-term symptoms.

    https://www.medrxiv.org/content/10.1101/2023.04.05.23288157v1
     
    Andy, Apr 6, 2023
    #1
    Robert 1973, Peter Trewhitt and DokaGirl like this.
  2. Hutan

    Hutan Moderator Staff Member

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    Location:
    Aotearoa New Zealand
    I don't think I can be bothered giving this study much time. A definition of PCC as at least one elevated symptom at 3 months is just way too loose. There are too many problems with assuming test-negative controls didn't have Covid. And the mixing of symptoms (and therefore different causes such as ME/CFS; lung damage and so on) reduces the ability to draw sound conclusions further.

    What I do find interesting is that Knoop and crew did this study. If the incidence of post-covid symptoms varies by covid strain, does that not suggest biological mechanisms? I didn't see any BPS spin in that abstract, and I fully expected it.
     
    Last edited: Apr 7, 2023
    Hutan, Apr 6, 2023
    #2
    SNT Gatchaman, Sean, RedFox and 6 others like this.
  3. Sean

    Sean Moderator Staff Member

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    7,608
    Location:
    Australia
    My first thought too.

    They could argue that the psycho-social influences become less influential over time with general public exposure and awareness. But that might be a difficult one to run. Could just as easily argue that it gets worse. Even that an essential feature of 'functional' disorders is that they are socially contagious and thus tend to become more widespread and entrenched over time, especially when publicly controversial. Otherwise they would be be self limiting and not a serious problem affecting up to [checks notes] 50% of primary care presentations, allegedly.
     
    Sean, Apr 7, 2023
    #3
    RedFox, alktipping, Peter Trewhitt and 3 others like this.
  4. rvallee

    rvallee Senior Member (Voting Rights)

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    Canada
    Expecting reason and logical consistency? Uh. Bold.
     
    rvallee, Apr 7, 2023
    #4
    alktipping, Peter Trewhitt and Hutan like this.

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