Low antispike antibody levels correlate with poor outcomes in COVID‐19 breakthrough hospitalizations

Abstract

Background While COVID‐19 immunization programs attempted to reach targeted rates, cases rose significantly since the emergence of the delta variant. This retrospective cohort study describes the correlation between antispike antibodies and outcomes of hospitalized, breakthrough cases during the delta variant surge. Methods All patients with positive SARS‐CoV‐2 polymerase chain reaction hospitalized at Mayo Clinic Florida from 19 June 2021 to 11 November 2021 were considered for analysis. Cases were analyzed by vaccination status. Breakthrough cases were then analyzed by low and high antibody titers against SARS‐CoV‐2 spike protein, with a cut‐off value of ≥132 U/ml. Outcomes included hospital length of stay (LOS), need for intensive care unit (ICU), mechanical ventilation, and mortality. We used 1:1 nearest neighbor propensity score matching without replacement to assess for confounders. Results Among 627 hospitalized patients with COVID‐19, vaccine breakthrough cases were older with more comorbidities compared to unvaccinated. After propensity score matching, the unvaccinated patients had higher mortality (27 [28.4%] vs. 12 [12.6%], p = 0.002) and LOS (7 [1.0–57.0] vs. 5 [1.0–31.0] days, p = 0.011). In breakthrough cases, low‐titer patients were more likely to be solid organ transplant recipients (16 [34.0%] vs. 9 [12.3%], p = 0.006), with higher need for ICU care (24 [51.1%] vs. 22 [11.0%], p = 0.034), longer hospital LOS (median 6 vs. 5 days, p = 0.013), and higher mortality (10 [21.3%] vs. 5 [6.8%], p = 0.025) than high‐titer patients. Conclusions Hospitalized breakthrough cases were more likely to have underlying risk factors than unvaccinated patients. Low‐spike antibody titers may serve as an indicator for poor prognosis in breakthrough cases admitted to the hospital.

Clinical Effectiveness of SARS-CoV-2 Vaccination in Renal Transplant Recipients. Antibody Levels Impact in Pneumonia and Death

“…The cutoff point of the antibody titers proposed in these studies is 132 AU/ mL. 21 Our results also described that patient who did not develop a broad humoral immunity after vaccination (<100 AU/mL) also showed an unfavorable evolution, in terms of the development of death and pneumonia, compared with those who did have a greater response. In fact, patients who do not develop antibodies postvaccine (0-20 AU/mL) had similar mortality rate to those who did not receive the vaccine in earlier COVID-19 waves (18%) (Figure 3).…”

“…As far as the titer of antibodies predicting protection against COVID-19 in RTRs is concerned, little information exists to date. Sanghavi et al 21 described in a study that included SOTRs, that patients with low-titer patient had higher need for intensive care unit care (51.1 versus 11%) and higher mortality (21.3% versus 6.8%) than high-titer patients. The cutoff point of the antibody titers proposed in these studies is 132 AU/ mL.…”

“…19 Despite the benefits of the vaccine, even of a third dose, up to 30% of our patients remain with a low titer of antibodies, which could be associated a worse clinical outcome. 19 Diverse studies have demonstrated the efficacy of the mRNA vaccines in terms of antibody development against SARS-CoV-2, [20][21][22]35 but to date, there is controversial the value of antibody titers to consider that a patient is actually protected from symptomatic or severe SARS-CoV-2 infection.…”

Impact of vaccination on the presence and severity of symptoms of hospitalised patients with an infection by the Omicron variant (B.1.1.529) of the SARS-CoV-2 (subvariant BA.1)

“…Moreover, we included patients from four countries, and our results may have been different if more countries (either European or not) had been represented. In addition, we did not perform anti-Spike serology at admission; anti-Spike antibody level has been shown to be associated with prognosis (Plūme et al 2022; Sanghavi et al 2022), and it might have facilitated understanding of the severity of SARS-CoV-2 infection in some vaccinated subjects, in particular among immunosuppressed subjects who could present lesser response to vaccines. In addition, availability of antiviral treatment was not comparable between the Delta and the Omicron wave, which could have had an impact on mortality.…”

Conserved longitudinal alterations of anti-S-protein IgG subclasses in disease progression in initial ancestral Wuhan and vaccine breakthrough Delta infections

“…The incidence of severe cases has greatly reduced ( Selvaraj et al, 2022 ). However, vaccine breakthrough infections do occur, potentially due to a suboptimal anti-S-protein antibody response ( Sanghavi et al, 2022 ). Thus, there is a critical need to better understand the humoral immunity against the S protein in both unvaccinated and vaccinated individuals to inform public health decisions on primary or booster vaccination and, possibly, treatment and prophylaxis.…”