ABSTRACT
commonly worldwide but their effectiveness in participants with cirrhosis is unknown. We explored the effectiveness of vaccination with the Janssen Ad.26.COV2.S compared to the mRNA Pfizer BNT162b2 or Moderna 1273-mRNA vaccine in participants with cirrhosis. Method: This was a test-negative case control study among participants with cirrhosis. This study design is widely used in evaluations of vaccine effectiveness and has the advantage of minimizing biases associated with access to vaccination or health care. Cases were those who were SARS CoV2 PCR positive, controls were those who tested negative during the study period between March 15, 2021 and October 3, 2021. Participants who did not undergo SARS CoV2 PCR testing, who had COVID-19 before the study period, or received a liver transplant, were excluded. COVID-19 was classified based on individual chart review using the National Institute of Health (NIH) COVID-19 severity scale as asymptomatic, mild, moderate, severe or critical illness. Propensity score matching was used to match test positive cases and test negative controls. The propensity score of having COVID-19 were derived from a logistic regression that adjusted for the participant's sex, age, date of testing, race/ethnicity, location, alcohol as the etiology of liver disease, body mass index (BMI), diabetes mellitus, current tobacco use, current alcohol use, co-morbidities, and the Child Turcotte Pugh score. Multinomial logistic regression models were fit for COVID-19, to assess the adjusted effect from vaccination with either the Ad.26.COV2.S or the mRNA-1273 or BNT162b2 vaccines. Results: A total of 955 cases and 955 matched controls were included in the study population. The two groups were well matched to all baseline characteristics. The Ad.26.COV2.S vaccine had an effectiveness of 64% against COVID-19 (adjusted Odds Ratio [aOR] 0.36, 95% CI 0.20-0.62, p=0.005). Effectiveness was lowest with asymptomatic illness (aOR 0.42, 0.18-0.73, p=0.03), and higher against mild (aOR 0.36, 0.15-0.63, p= 0.006), moderate (aOR 0.33, 0.14-0.49, p=0.002) and severe/critical (aOR 0.24, 0.08-0.83, p=0.04) COVID-19. In the same period, mRNA vaccines had a 73% effectiveness against overall COVID-19 (aOR 0.27, 0.19-0.37, p<0.0001), progressively higher from asymptomatic (aOR 0.38, 0.23-0.59, p=0.0004) to mild (aOR 0.29, 0.18-0.42, p<0.0001), moderate (aOR 0.27, 0.18-0.36, p<0.0001), and severe or critical illness (aOR 0.17, 0.06-0.32, p<0.0001). There were no statistically significant differences between the viral vector and mRNA vaccines. Conclusion: In participants with cirrhosis, the Ad.26.COV2.S demonstrated a 64% effectiveness against COVID-19, and a 74% effectiveness against severe or critical COVID-19, similar to that associated with mRNA vaccines. (Figure Presented)
ABSTRACT
Background and Aims: Immunity to Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be either infection-induced or vaccine-induced. The duration of protective immunity following SARS-CoV-2 infection and how this compares with that from vaccination is presently unclear. Cirrhosis is associated with vaccine hyporesponsiveness to several vaccines include COVID-19 mRNA vaccines. The objective of our study was to compare infection-induced and vaccine-induced immunity against COVID-19 among patients with cirrhosis. Methods: This was a retrospective cohort study among patients with cirrhosis. Vaccine-induced immunity group was defined as participants with cirrhosis who were fully vaccinated with an mRNA vaccine and received the first dose of the mRNA vaccine between 12/18/2020 and 4/1/2021. Infection-induced immunity was defined as participants who had their first positive SARS-CoV-2 PCR in the same study period. The outcome was a positive SARS-CoV-2 PCR more than 60 days after previous infection or vaccination. Patients were followed until the outcome, death or the end of the study period (11/16/21). COVID-19 cases were classified based on individual chart review using the National Institute of Health (NIH) COVID-19 severity scale as asymptomatic, mild, moderate, severe or critical illness. The two groups were matched 1:3 using propensity score (PS) matching, with PS scores calculated based on variables associated with COVID-19 severity, including for the date of infection or first dose of vaccnation, and location, to account for variants. Cox proportional hazards models were fit from the immunity generating event to outcome (SARS-CoV-2PCR). Logistic regression models were also fit for the outcome (positive SARS-CoV-2 PCR) after the immunity generating event. Results: There were 443 participants in the infection-induced group, that were PS matched with 1,329 participants in the vaccine-induced group. The two groups were well matched after PS matching. On multivariable Cox hazard model, vaccine-induced immunity was associated with a 75% reduction in COVID-19 compared to infection-induced immunity (adjusted Hazard Ratio 0.25, 95% CI 0.15-0.43, p<0.0001). On multinomial logistic regression analysis, vaccine-induced immunity was associated with a 80% reduction in asymptomatic (adjusted Odds Ratio [aOR] 0.20, 95% CI 0.09-0.47, p-0.0002), 64% reduction in mild (aOR 0.36, 95% CI 0.13-0.97, p=0.048), and 79% reduction in severe or critical COVID-19 (aOR 0.21,95% CI 0.06-0.74, p=0.02) compared to infection-induced immunity. There were no observed differences between the two groups for moderate COVID-19 (aOR 0.31, 95% CI 0.06-1.56, p=0.16). Conclusions: In participants with cirrhosis, vaccine-induced immunity is associated with a significantly greater protection against COVID-19 compared to infection-induced immunity.[Figure Presented]
ABSTRACT
Background and Aims: The recent COVID-19 pandemic has upended health care delivery in the United States and the world, resulting in a rapid switch from in-person patient interactions to telemedicine. While telemedicine evaluation offers many advantages including convenience, patient satisfaction and improved access, it is unclear if it is an adequate substitute for in-person evaluation for complex interventions such as liver transplantation. There is a dearth of multi-center data on transplant evaluation using telemedicine and its impact on liver transplant outcomes. Methods: We performed a retrospective analysis of 1,118 non-local patients who underwent non-urgent evaluation for liver transplantation within the Veterans Affairs Health care system, which had implemented liver transplant evaluation by telemedicine predating COVID-19. During the study period, 176 patients underwent initial evaluation by telemedicine and 942, by an in-person evaluation. We studied the association of evaluation by telemedicine on pre-transplant mortality, as well as with time to evaluation, listing and transplantation. Results: After its initial introduction, the proportion of patients who underwent transplant evaluation by telemedicine, increased from 1.6% in 2013 to 20.2% in 2017. The percentage of telemedicine adoption varied across centers, from 0.5% to 44.2% of all evaluations. Patients in the telemedicine group had a shorter unadjusted time from referral to evaluation (20.0 vs. 27.0 days, p<0.0001), and listing (65.0 vs. 99.0 days, p<0.0001). There were no differences in time from referral to transplantation (220.5 vs. 265.5 days, p=0.25). These differences were maintained on an adjusted analysis, with transplant evaluation by telemedicine associated with a shorter adjusted time from referral to evaluation (19.4 vs. 28.9 days, p<0.001), and listing (97.4 vs. 118.7 days, p=0.0003), but not to transplantation (253.3 vs. 311.2 days, p=0.06). Telemedicine offered the highest benefit in patients with MELD below 20. Conclusion: In a national multi-center study within the VA system, Liver transplant evaluation by telemedicine is associated with a shorter time to evaluation and listing, and a trend towards shorter time to transplantation. (Table presented.) Time from referral to evaluation, listing and transplantation, by telemedicne or in-person evaluation (Generalized linear regression) by MELD-Na