Identifying Veterans Who Benefit From Nirmatrelvir-Ritonavir: A Target Trial Emulation.

BACKGROUND: Nirmatrelvir-ritonavir is recommended for persons at risk for severe coronavirus disease 2019 (COVID-19) but remains underutilized. Information on which eligible groups are likely to benefit from treatment is needed. METHODS: We conducted a target trial emulation study in the Veterans Health Administration comparing nirmatrelvir-ritonavir treated versus matched untreated veterans at risk for severe COVID-19 who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from April 2022 through March 2023. We measured incidence of any hospitalization or all-cause mortality at 30 days. Outcomes were measured for the entire cohort, as well as among subgroups defined by 30-day risk of death or hospitalization, estimated using an ensemble risk prediction model. RESULTS: Participants were 87% male with median age 66 years and 16% unvaccinated. Compared with matched untreated participants, those treated with nirmatrelvir-ritonavir (n = 24 205) had a lower 30-day risk for hospitalization (1.80% vs 2.30%; risk difference [RD], -0.50% points [95% confidence interval {CI}: -.69 to -.35]) and death (0.11% vs 0.30%; RD, -0.20 [95% CI: -.24 to -.13]). The greatest reductions in combined hospitalization or death were observed in the highest risk quartile (RD -2.85 [95% CI: -3.94 to -1.76]), immunocompromised persons (RD -1.91 [95% CI: -3.09 to -.74]), and persons aged ≥75 years (RD -1.16 [95% CI: -1.73 to -.59]). No reductions were observed in the 2 lowest risk quartiles or persons younger than 65 years. CONCLUSIONS: Nirmatrelvir-ritonavir was effective in reducing 30-day hospitalization and death in older veterans, those at highest predicted risk for severe outcomes, and immunocompromised groups. Benefit was not observed in younger veterans or groups at lower predicted risk for hospitalization and death.

Hepatocellular carcinoma risk decreases as time accrues following hepatitis C virus eradication.

BACKGROUND: It is unclear whether the risk of hepatocellular carcinoma (HCC) decreases over time following hepatitis C virus (HCV) eradication. AIM: To determine if patients who have accrued longer time since sustained virologic response (SVR) have a lower risk of HCC than those with less time since SVR METHODS: We conducted a retrospective cohort study of all HCV-infected Veterans Affairs patients who achieved SVR before 1 January 2018 and remained alive without a diagnosis of HCC as of 1 January 2019 (n = 75,965). We ascertained their baseline characteristics as of 1 January 2019 (time zero), including time accrued since SVR and followed them for the subsequent 12 months for incident HCC. We used multivariable Cox proportional hazards regression to determine the association between time since SVR and HCC risk after adjusting for age, race/ethnicity, sex, diabetes, hypertension, body mass index, alcohol use, Charlson Comorbidity Index, Fibrosis-4 score, HCV genotype, hepatitis B virus co-infection and HIV co-infection. RESULTS: 96.0% were male; mean age was 64.6 years. Among those with cirrhosis (n = 19,678, 25.9%), compared to patients who had accrued only ≥1 to 2 years since SVR (HCC incidence 2.71/100 person-years), those who had accrued >2 to 4 years (2.11/100 person-years, aHR 0.80, 95% CI 0.63-1.01) and >4 to 6 years (1.65/100 person-years, aHR 0.61, 95% CI 0.41-0.90) had progressively lower HCC risk. However, HCC risk appeared to plateau for those with >6 years since SVR (1.68/100 person-years, aHR 0.70, 95% CI 0.46-1.07). Among those without cirrhosis, HCC risk was 0.23-0.27/100 person-years without a significant association between time since SVR and HCC risk. CONCLUSIONS: Among patients with cirrhosis and cured HCV infection, HCC risk declined progressively up to 6 years post-SVR-although it remained well above thresholds that warrant screening. This suggests that time since SVR can inform HCC surveillance strategies in patients with cured HCV infection and can be incorporated into HCC risk prediction models.

Risk of Suicide-Related Outcomes After SARS-COV-2 Infection: Results from a Nationwide Observational Matched Cohort of US Veterans.

BACKGROUND: Negative mental health-related effects of SARS-COV-2 infection are increasingly evident. However, the impact on suicide-related outcomes is poorly understood, especially among populations at elevated risk. OBJECTIVE: To determine risk of suicide attempts and other self-directed violence (SDV) after SARS-COV-2 infection in a high-risk population. DESIGN: We employed an observational design supported by comprehensive electronic health records from the Veterans Health Administration (VHA) to examine the association of SARS-COV-2 infection with suicide attempts and other SDV within one year of infection. Veterans with SARS-COV-2 infections were matched 1:5 with non-infected comparators each month. Three periods after index were evaluated: days 1-30, days 31-365, and days 1-365. PARTICIPANTS: VHA patients infected with SARS-COV-2 between March 1, 2020 and March 31, 2021 and matched non-infected Veteran comparators. MAIN MEASURES: Suicide attempt and other SDV events for the COVID-19 and non-infected comparator groups were analyzed using incidence rates per 100,000 person years and hazard ratios from Cox regressions modeling time from matched index date to first event. Subgroups were also examined. KEY RESULTS: 198,938 veterans with SARS-COV-2 (COVID-19 group) and 992,036 comparators were included. Unadjusted one-year incidence per 100,000 for suicide attempt and other SDV was higher among the COVID-19 group: 355 vs 250 and 327 vs 235, respectively. The COVID-19 group had higher risk than comparators for suicide attempts: days 1-30 hazard ratio (HR) = 2.54 (CI:2.05, 3.15), days 31-365 HR = 1.30 (CI:1.19, 1.43) and days 1-365 HR = 1.41 (CI:1.30, 1.54), and for other SDV: days 1-30 HR = 1.94 (CI:1.51, 2.49), days 31-365 HR = 1.32 (CI:1.20, 1.45) and days 1-365 HR = 1.38 (CI:1.26, 1.51). CONCLUSIONS: COVID-19 patients had higher risks of both suicide attempts and other forms of SDV compared to uninfected comparators, which persisted for at least one year after infection. Results support suicide risk screening of those infected with SARS-COV-2 to identify opportunities to prevent self-harm.

Effectiveness of Nirmatrelvir-Ritonavir Against the Development of Post-COVID-19 Conditions Among U.S. Veterans : A Target Trial Emulation.

BACKGROUND: COVID-19 has been linked to the development of many post-COVID-19 conditions (PCCs) after acute infection. Limited information is available on the effectiveness of oral antivirals used to treat acute COVID-19 in preventing the development of PCCs. OBJECTIVE: To measure the effectiveness of outpatient treatment of COVID-19 with nirmatrelvir-ritonavir in preventing PCCs. DESIGN: Retrospective target trial emulation study comparing matched cohorts receiving nirmatrelvir-ritonavir versus no treatment. SETTING: Veterans Health Administration (VHA). PARTICIPANTS: Nonhospitalized veterans in VHA care who were at risk for severe COVID-19 and tested positive for SARS-CoV-2 during January through July 2022. INTERVENTION: Nirmatrelvir-ritonavir treatment for acute COVID-19. MEASUREMENTS: Cumulative incidence of 31 potential PCCs at 31 to 180 days after treatment or a matched index date, including cardiac, pulmonary, renal, thromboembolic, gastrointestinal, neurologic, mental health, musculoskeletal, endocrine, and general conditions and symptoms. RESULTS: Eighty-six percent of the participants were male, with a median age of 66 years, and 17.5% were unvaccinated. Baseline characteristics were well balanced between participants treated with nirmatrelvir-ritonavir and matched untreated comparators. No differences were observed between participants treated with nirmatrelvir-ritonavir (n = 9593) and their matched untreated comparators in the incidence of most PCCs examined individually or grouped by organ system, except for lower combined risk for venous thromboembolism and pulmonary embolism (subhazard ratio, 0.65 [95% CI, 0.44 to 0.97]; cumulative incidence difference, -0.29 percentage points [CI, -0.52 to -0.05 percentage points]). LIMITATIONS: Ascertainment of PCCs using International Classification of Diseases, 10th Revision, codes may be inaccurate. Evaluation of many outcomes could have resulted in spurious associations with combined thromboembolic events by chance. CONCLUSION: Out of 31 potential PCCs, only combined thromboembolic events seemed to be reduced by nirmatrelvir-ritonavir. PRIMARY FUNDING SOURCE: U.S. Department of Veterans Affairs.

Anti-SARS-CoV-2 Pharmacotherapies Among Nonhospitalized US Veterans, January 2022 to January 2023.

Importance: Several pharmacotherapies have been authorized to treat nonhospitalized persons with symptomatic COVID-19. Longitudinal information on the use of these therapies is needed. Objective: To analyze trends and factors associated with prescription of outpatient COVID-19 pharmacotherapies within the Veterans Health Administration (VHA). Design, Setting, and Participants: This cohort study evaluated nonhospitalized veterans in VHA care who tested positive for SARS-CoV-2 from January 2022 through January 2023 using VHA and linked Community Care and Medicare databases. Exposures: Demographic characteristics, underlying medical conditions, COVID-19 vaccination, and regional and local systems of care, including Veterans Integrated Services Networks (VISNs). Main Outcomes and Measures: Monthly receipt of any COVID-19 pharmacotherapy (nirmatrelvir-ritonavir, molnupiravir, sotrovimab, or bebtelovimab) was described. Multivariable logistic regression was used to identify factors independently associated with receipt of any vs no COVID-19 pharmacotherapy. Results: Among 285 710 veterans (median [IQR] age, 63.1 [49.9-73.7] years; 247 358 males [86.6%]; 28 444 Hispanic [10.0%]; 61 269 Black [21.4%] and 198 863 White [69.6%]) who tested positive for SARS-CoV-2 between January 2022 and January 2023, the proportion receiving any pharmacotherapy increased from 3285 of 102 343 veterans (3.2%) in January 2022 to 5180 of 21 688 veterans (23.9%) in August 2022. The proportion declined to 2194 of 10 551 veterans (20.8%) by January 2023. Across VISNs, the range in proportion of patients who tested positive who received nirmatrelvir-ritonavir or molnupiravir during January 2023 was 41 of 692 veterans (5.9%) to 106 of 494 veterans (21.4%) and 2.1% to 120 of 1074 veterans (11.1%), respectively. Veterans receiving any treatment were more likely to be older (adjusted odds ratio [aOR] for ages 65-74 vs 50-64 years, 1.18; 95% CI, 1.14-1.22; aOR for ages ≥75 vs 50-64 years, 1.19; 95% CI, 1.15-1.23) and have a higher Charlson Comorbidity Index score (aOR for CCI ≥6 vs 0, 1.52; 95% CI, 1.44-1.59). Compared with White veterans, Black veterans (aOR, 1.06; 95% CI, 1.02-1.09) were more likely to receive treatment, and compared with non-Hispanic veterans, Hispanic veterans (aOR 1.06; 95% CI, 1.01-1.11) were more likely to receive treatment. Conclusions And Relevance: This study found that prescription of outpatient COVID-19 pharmacotherapies in the VHA peaked in August 2022 and declined thereafter. There were large regional differences in patterns of nirmatrelvir-ritonavir and molnupiravir use.

Effectiveness of COVID-19 Treatment With Nirmatrelvir-Ritonavir or Molnupiravir Among U.S. Veterans: Target Trial Emulation Studies With One-Month and Six-Month Outcomes.

BACKGROUND: Information about the effectiveness of oral antivirals in preventing short- and long-term COVID-19-related outcomes in the setting of Omicron variant transmission and COVID-19 vaccination is limited. OBJECTIVE: To measure the effectiveness of nirmatrelvir-ritonavir and molnupiravir for outpatient treatment of COVID-19. DESIGN: Three retrospective target trial emulation studies comparing matched cohorts of nirmatrelvir-ritonavir versus no treatment, molnupiravir versus no treatment, and nirmatrelvir-ritonavir versus molnupiravir. SETTING: Veterans Health Administration (VHA). PARTICIPANTS: Nonhospitalized veterans in VHA care who were at risk for severe COVID-19 and tested positive for SARS-CoV-2 during January through July 2022. INTERVENTION: Nirmatrelvir-ritonavir or molnupiravir pharmacotherapy. MEASUREMENTS: Incidence of any hospitalization or all-cause mortality at 30 days and from 31 to 180 days. RESULTS: Eighty-seven percent of participants were male; the median age was 66 years, and 18% were unvaccinated. Compared with matched untreated control participants, those treated with nirmatrelvir-ritonavir (n = 9607) had lower 30-day risk for hospitalization (22.07 vs. 30.32 per 1000 participants; risk difference [RD], -8.25 [95% CI, -12.27 to -4.23] per 1000 participants) and death (1.25 vs. 5.47 per 1000 participants; RD, -4.22 [CI, -5.45 to -3.00] per 1000 participants). Among persons alive at day 31, reductions were seen in 31- to 180-day incidence of death (hazard ratio, 0.66 [CI, 0.49 to 0.89]) but not hospitalization (subhazard ratio, 0.90 [CI, 0.79 to 1.02]). Molnupiravir-treated participants (n = 3504) had lower 30-day and 31- to 180-day risks for death (3.14 vs. 13.56 per 1000 participants at 30 days; RD, -10.42 [CI, -13.49 to -7.35] per 1000 participants; hazard ratio at 31 to 180 days, 0.67 [CI, 0.48 to 0.95]) but not hospitalization. A difference in 30-day or 31- to 180-day risk for hospitalization or death was not observed between matched nirmatrelvir- or molnupiravir-treated participants. LIMITATION: The date of COVID-19 symptom onset for most veterans was unknown. CONCLUSION: Nirmatrelvir-ritonavir was effective in reducing 30-day hospitalization and death. Molnupiravir was associated with a benefit for 30-day mortality but not hospitalization. Further reductions in mortality from 31 to 180 days were observed with both antivirals. PRIMARY FUNDING SOURCE: U.S. Department of Veterans Affairs.

Associations of Race and Ethnicity with Hepatocellular Carcinoma, Decompensation, and Mortality in US Veterans with Cirrhosis.

BACKGROUND: Among patients with cirrhosis, it remains unclear whether there are racial/ethnic differences in cirrhosis complications and mortality. We examined the associations between race/ethnicity and risk for hepatocellular carcinoma (HCC), cirrhosis decompensation, and all-cause mortality overall and by cirrhosis etiology. METHODS: US Veterans diagnosed with cirrhosis from 2001 to 2014 (n = 120,992), due to hepatitis C virus (HCV; n = 55,814), alcohol-associated liver disease (ALD; n = 36,323), hepatitis B virus (HBV; n = 1,972), nonalcoholic fatty liver disease (NAFLD; n = 17,789), or other (n = 9,094), were followed through 2020 for incident HCC (n = 10,242), cirrhosis decompensation (n = 27,887), and mortality (n = 81,441). Multivariable Cox proportional hazards regression was used to estimate adjusted hazard ratios (aHR) and 95% confidence intervals (CI). RESULTS: Compared with non-Hispanic White patients, Hispanic patients had higher risk for HCC overall (aHR, 1.32; 95% CI, 1.24-1.41) and by cirrhosis etiology, particularly for ALD- (aHR, 1.63; 95% CI, 1.42-1.87) and NAFLD-cirrhosis (aHR, 1.76; 95% CI, 1.41-2.20), whereas non-Hispanic Black patients had lower HCC risk in ALD- (aHR, 0.79; 95% CI, 0.63-0.98) and NAFLD-cirrhosis (aHR, 0.54; 95% CI, 0.33-0.89). Asian patients had higher HCC risk (aHR, 1.70; 95% CI, 1.29-2.23), driven by HCV- and HBV-cirrhosis. Non-Hispanic Black patients had lower risk for cirrhosis decompensation overall (aHR, 0.71; 95% CI, 0.68-0.74) and by cirrhosis etiology. There was lower risk for mortality among all other racial/ethnic groups compared with non-Hispanic White patients. CONCLUSIONS: Race/ethnicity is an important predictor for risk of developing HCC, decompensation, and mortality. IMPACT: Future research should examine factors underlying these racial/ethnic differences to inform prevention, screening, and treatment for patients with cirrhosis.

Bilateral palpebral reduction and concurrent mycoplasmosis in a wild Agassiz's desert tortoise (Gopherus agassizii).

A wild Agassiz's desert tortoise, Gopherus agassizii, with bilateral eyelid reduction and plaques of tissue covering the superior surface of both corneas was examined in the field and subsequently submitted to the University of Florida for diagnostics. Polymerase chain reaction (PCR), from a swab of both corneas, was positive for Mycoplasma agassizii. Two months later, the tortoise was euthanatized and necropsied. There was increased bulbar exposure associated with dermal excoriation of periocular scales in both superior and inferior palpebra resulting in an increased palpebral fissure opening. Concurrently, there was bilateral conjunctivitis of the nictitating membranes and squamous metaplasia of the bulbar conjunctiva. Using PCR, Mycoplasma testudineum, another pathogen of tortoises, was identified in both nasal cavities, and the upper respiratory tract histopathological findings were consistent with those described for M. testudineum in Agassiz's desert tortoises. Although eye disease has been reported in desert and gopher (Gopherus polyphemus) tortoises with mycoplasmosis, widespread loss of palpebral tissue, conjunctivitis of the nictitans, and squamous metaplasia of the bulbar conjunctiva have not been reported in tortoises.

Design and analysis of outcomes following SARS-CoV-2 infection in veterans.

BACKGROUND: Understanding how SARS-CoV-2 infection impacts long-term patient outcomes requires identification of comparable persons with and without infection. We report the design and implementation of a matching strategy employed by the Department of Veterans Affairs' (VA) COVID-19 Observational Research Collaboratory (CORC) to develop comparable cohorts of SARS-CoV-2 infected and uninfected persons for the purpose of inferring potential causative long-term adverse effects of SARS-CoV-2 infection in the Veteran population. METHODS: In a retrospective cohort study, we identified VA health care system patients who were and were not infected with SARS-CoV-2 on a rolling monthly basis. We generated matched cohorts within each month utilizing a combination of exact and time-varying propensity score matching based on electronic health record (EHR)-derived covariates that can be confounders or risk factors across a range of outcomes. RESULTS: From an initial pool of 126,689,864 person-months of observation, we generated final matched cohorts of 208,536 Veterans infected between March 2020-April 2021 and 3,014,091 uninfected Veterans. Matched cohorts were well-balanced on all 39 covariates used in matching after excluding patients for: no VA health care utilization; implausible age, weight, or height; living outside of the 50 states or Washington, D.C.; prior SARS-CoV-2 diagnosis per Medicare claims; or lack of a suitable match. Most Veterans in the matched cohort were male (88.3%), non-Hispanic (87.1%), white (67.2%), and living in urban areas (71.5%), with a mean age of 60.6, BMI of 31.3, Gagne comorbidity score of 1.4 and a mean of 2.3 CDC high-risk conditions. The most common diagnoses were hypertension (61.4%), diabetes (34.3%), major depression (32.2%), coronary heart disease (28.5%), PTSD (25.5%), anxiety (22.5%), and chronic kidney disease (22.5%). CONCLUSION: This successful creation of matched SARS-CoV-2 infected and uninfected patient cohorts from the largest integrated health system in the United States will support cohort studies of outcomes derived from EHRs and sample selection for qualitative interviews and patient surveys. These studies will increase our understanding of the long-term outcomes of Veterans who were infected with SARS-CoV-2.

Rates of and Factors Associated With Primary and Booster COVID-19 Vaccine Receipt by US Veterans, December 2020 to June 2022.

Importance: COVID-19 vaccination rates remain suboptimal in the US. Identifying factors associated with vaccination can highlight existing gaps and guide targeted interventions to improve vaccination access and uptake. Objective: To describe incidence and patient characteristics associated with primary, first booster, and second booster COVID-19 vaccination in the Veterans Health Administration (VHA). Design, Setting, and Participants: This retrospective cohort study assessed US veterans receiving care in VHA medical centers and outpatient clinics as of December 1, 2020. All VHA enrollees with an inpatient, outpatient, or telehealth encounter in VHA as well as a primary care physician appointment in the preceding 24 months were included. Exposures: Demographic characteristics, place of residence, prior SARS-CoV-2 infection, and underlying medical conditions. Main Outcomes and Measures: Cumulative incidence of primary, first booster, and second booster COVID-19 vaccination through June 2022. Cox proportional hazards regression was used to identify factors independently associated with COVID-19 vaccination. Results: Among 5 632 413 veterans included in the study, 5 094 392 (90.4%) were male, the median (IQR) age was 66 (51-74) years, 1 032 334 (18.3%) were Black, 448 714 (8.0%) were Hispanic, and 4 202 173 (74.6%) were White. Through June 2022, cumulative incidences were 69.0% for primary vaccination, 42.9% for first booster, and 9.3% for second booster. Cumulative incidence for primary vaccination increased with increasing age, from 46.9% (95% CI, 46.8%-47.0%) among veterans aged 18 to 49 years to 82.9% (95% CI, 82.8%-83.0%) among veterans aged 80 to 84 years. More Black veterans completed primary vaccination (71.7%; 95% CI, 71.6%-71.8%) compared with White veterans (68.9%; 95% CI, 68.9%-69.0%), and more urban-dwelling veterans completed primary vaccination (70.9%; 95% CI, 70.9%-71.0%) compared with highly rural-dwelling veterans (63.8%; 95% CI, 63.4%-64.1%). Factors independently associated with higher likelihood of both primary and booster vaccination included older age, female sex, Asian or Black race, Hispanic ethnicity, urban residence, and lack of prior SARS-CoV-2 infection. Conclusions and Relevance: In this cohort study of US veterans, COVID-19 vaccination coverage through June 2022 was suboptimal. Primary vaccination can be improved among younger, rural-dwelling veterans. Greater uptake of booster vaccination among all veterans is needed.

Effectiveness of COVID-19 treatment with nirmatrelvir-ritonavir or molnupiravir among U.S. Veterans: target trial emulation studies with one-month and six-month outcomes.

Background: Information about the effectiveness of oral antivirals in preventing short- and long-term COVID-19-related outcomes during the Omicron surge is limited. We sought to determine the effectiveness of nirmatrelvir-ritonavir and molnupiravir for the outpatient treatment of COVID-19. Methods: We conducted three retrospective target trial emulation studies comparing matched patient cohorts who received nirmatrelvir-ritonavir versus no treatment, molnupiravir versus no treatment, and nirmatrelvir-ritonavir versus molnupiravir in the Veterans Health Administration (VHA). Participants were Veterans in VHA care at risk for severe COVID-19 who tested positive for SARS-CoV-2 in the outpatient setting during January and February 2022. Primary outcomes included all-cause 30-day hospitalization or death and 31-180-day incidence of acute or long-term care admission, death, or post-COVID-19 conditions. For 30-day outcomes, we calculated unadjusted risk rates, risk differences, and risk ratios. For 31-180-day outcomes, we used unadjusted time-to-event analyses. Results: Participants were 90% male with median age 67 years and 26% unvaccinated. Compared to matched untreated controls, nirmatrelvir-ritonavir-treated participants (N=1,587) had a lower 30-day risk of hospitalization (27.10/1000 versus 41.06/1000, risk difference [RD] - 13.97, 95% CI -23.85 to -4.09) and death (3.15/1000 versus 14.86/1000, RD -11.71, 95% CI - 16.07 to -7.35). Among persons who were alive at day 31, further significant reductions in 31-180-day incidence of hospitalization (sub-hazard ratio 1.07, 95% CI 0.83 to 1.37) or death (hazard ratio 0.61, 95% CI 0.35 to 1.08) were not observed. Molnupiravir-treated participants aged ≥65 years (n=543) had a lower combined 30-day risk of hospitalization or death (55.25/1000 versus 82.35/1000, RD -27.10, 95% CI -50.63 to -3.58). A statistically significant difference in 30-day or 31-180-day risk of hospitalization or death was not observed between matched nirmatrelvir- or molnupiravir-treated participants. Incidence of most post-COVID conditions was similar across comparison groups. Conclusions: Nirmatrelvir-ritonavir was highly effective in preventing 30-day hospitalization and death. Short-term benefit from molnupiravir was observed in older groups. Significant reductions in adverse outcomes from 31-180 days were not observed with either antiviral.

Effectiveness of mRNA COVID-19 Vaccine Boosters Against Infection, Hospitalization, and Death: A Target Trial Emulation in the Omicron (B.1.1.529) Variant Era.

BACKGROUND: The effectiveness of a third mRNA COVID-19 vaccine dose (booster dose) against the Omicron (B.1.1.529) variant is uncertain, especially in older, high-risk populations. OBJECTIVE: To determine mRNA booster vaccine effectiveness (VE) against SARS-CoV-2 infection, hospitalization, and death in the Omicron era by booster type, primary vaccine type, time since primary vaccination, age, and comorbidity burden. DESIGN: Retrospective matched cohort study designed to emulate a target trial of booster vaccination versus no booster, conducted from 1 December 2021 to 31 March 2022. SETTING: U.S. Department of Veterans Affairs health care system. PARTICIPANTS: Persons who had received 2 mRNA COVID-19 vaccine doses at least 5 months earlier. INTERVENTION: Booster monovalent mRNA vaccination (Pfizer-BioNTech's BNT162b2 or Moderna's mRNA-1273) versus no booster. MEASUREMENTS: Booster VE. RESULTS: Each group included 490 838 well-matched persons, who were predominantly male (88%), had a mean age of 63.0 years (SD, 14.0), and were followed for up to 121 days (mean, 79.8 days). Booster VE more than 10 days after a booster dose was 42.3% (95% CI, 40.6% to 43.9%) against SARS-CoV-2 infection, 53.3% (CI, 48.1% to 58.0%) against SARS-CoV-2-related hospitalization, and 79.1% (CI, 71.2% to 84.9%) against SARS-CoV-2-related death. Booster VE was similar for different booster types (BNT162b2 or mRNA-1273), age groups, and primary vaccination regimens but was significantly higher with longer time since primary vaccination and higher comorbidity burden. LIMITATION: Predominantly male population. CONCLUSION: Booster mRNA vaccination was highly effective in preventing death and moderately effective in preventing infection and hospitalization for up to 4 months after administration in the Omicron era. Increased uptake of booster vaccination, which is currently suboptimal, should be pursued to limit the morbidity and mortality of SARS-CoV-2 infection, especially in persons with high comorbidity burden. PRIMARY FUNDING SOURCE: U.S. Department of Veterans Affairs.

Combining FIB-4 and Liver Stiffness Into the FIB-5, a Single Model that Accurately Predicts Complications of Portal Hypertension.

INTRODUCTION: We aimed to combine the fibrosis (FIB)-4 score and fibroscan-derived liver stiffness (LS) into a single score (FIB-5) that predicts incident complications of portal hypertension (PH) in persons with compensated liver disease. METHODS: In this retrospective cohort study, we identified 5849 US veterans who underwent LS measurement from May 01, 2014 to June 30, 2019, and laboratory tests enabling FIB-4 calculation within 6 months of LS measurement. Patients were followed up from the LS measurement date until February 05, 2020, for incident complications of PH. We combined LS values and the individual components of the FIB-4 score (i.e. age, aspartate aminotransferase, alanine aminotransferase, and platelet count) using multivariable Cox proportional hazards modeling and the machine learning algorithm eXtreme gradient boosting to develop the C-FIB-5 and X-FIB-5 models, respectively. Models were internally validated using optimism-corrected measures. RESULTS: Among 5,849 patients, the mean age was 62.8 years, 95.9% were men, and the mean follow-up time was 2.14 ± 1.21 years. Within 3 years after LS measurement date, 116 (2.0%) patients developed complications of PH. The X-FIB-5 (area under the receiver operating characteristic [AUROC] 0.845) and C-FIB-5 scores (AUROC 0.868) demonstrated superior discrimination over LS (AUROC 0.688) and FIB-4 (AUROC 0.672) for predicting incident complications of PH. Both the X-FIB-5 and C-FIB-5 models demonstrated higher classification accuracy across all sensitivity cutoffs when compared with LS or FIB-4 alone. DISCUSSION: We combined LS and the individual components of the FIB-4 into a single scoring system (FIB-5, www.fib5.net ), which can help identify patients with compensated liver disease at risk of developing complications of PH.

PM2.5 air pollution exposure and nonalcoholic fatty liver disease in the Nationwide Inpatient Sample.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. Particulate matter air pollution <2.5 µm in diameter (PM2.5) is a ubiquitous exposure primarily produced from fossil fuel combustion. Previous epidemiologic studies have been mixed. The objective of this study was to examine the association between ambient PM2.5 exposure and NAFLD among hospitalized patients in the Nationwide Inpatient Sample (NIS). METHODS: We conducted a cross-sectional analysis of hospitalizations from 2001 to 2011 using the NIS, the largest nationally representative all-payer inpatient care administrative database in the United States. Average annual PM2.5 exposure was estimated by linking census tracts (based on NIS-provided hospital ZIP Codes) with a spatiotemporal exposure model. Clinical conditions were identified using hospital discharge diagnosis codes. Multivariable logistic regression incorporating discharge weights was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between PM2.5 exposure and odds of NAFLD among hospitalized patients adjusting for age, sex, race/ethnicity, year, individual- and area-level socioeconomic status, urbanicity, region, obesity, diabetes, metabolic syndrome, impaired fasting glucose, dyslipidemia, hypertension, obstructive sleep apnea, and smoking. RESULTS: There were 269,705 hospitalized patients with NAFLD from 2001 to 2011 (total unweighted n = 45,433,392 hospitalizations). Higher ambient PM2.5 exposure was associated with increased odds of NAFLD among hospitalized patients (adjusted OR: 1.24 per 10 µg/m3 increase, 95% CI 1.15-1.33, p < 0.01). There were statistically significant interactions between PM2.5 exposure and age, race/ethnicity, diabetes, smoking, and region, with stronger positive associations among patients who were aged ≥45 years, non-Hispanic White or Asian/Pacific Islander, non-diabetics, non-smokers, or in the Midwest and West regions, respectively. CONCLUSIONS: In this nationwide cross-sectional analysis of the NIS database, there was a positive association between ambient PM2.5 exposure and odds of NAFLD among hospitalized patients. Future research should examine the effects of long-term historical PM2.5 exposure and incident NAFLD cases.

A novel herpesvirus detected in 3 species of chelonians.

Herpesviruses are found in free-living and captive chelonian populations, often in association with morbidity and mortality. To date, all known chelonian herpesviruses fall within the subfamily Alphaherpesvirinae. We detected a novel herpesvirus in 3 species of chelonians: a captive leopard tortoise (Stigmochelys pardalis) in western TX, USA; a steppe tortoise (Testudo [Agrionemys] horsfieldii) found near Fort Irwin, CA, USA; and 2 free-living, three-toed box turtles (Terrapene mexicana triunguis) found in Forest Park, St. Louis, MO. The leopard tortoise was coinfected with the tortoise intranuclear coccidian and had clinical signs of upper respiratory tract disease. The steppe tortoise had mucopurulent nasal discharge and lethargy. One of the three-toed box turtles had no clinical signs; the other was found dead with signs of trauma after being observed with blepharedema, tympanic membrane swelling, cervical edema, and other clinical signs several weeks prior to death. Generally, the branching order of the turtle herpesviruses mirrors the divergence patterns of their hosts, consistent with codivergence. Based on phylogenetic analysis, this novel herpesvirus clusters with a clade of viruses that infect emydid hosts and is likely of box turtle origin. Therefore, we suggest the name terrapene alphaherpesvirus 3 (TerAHV3) for the novel virus. This virus also has the ability to host-jump to tortoises, and previously documented herpesviral morbidity tends to be more common in aberrant hosts. The relationship between clinical signs and infection with TerAHV3 in these animals is unclear, and further investigation is merited.

Comparison of Moderna versus Pfizer-BioNTech COVID-19 vaccine outcomes: A target trial emulation study in the U.S. Veterans Affairs healthcare system.

Background: mRNA COVID-19 vaccines manufactured by Pfizer-BioNTech (BNT162b2) and Moderna (mRNA-1273) have been shown to be efficacious but have not been compared in head-to-head clinical trials. Methods: We designed this observational study to emulate a target trial of COVID-19 vaccination by BNT162b2 versus mRNA-1273 among persons who underwent vaccination in the national U.S. Veterans Affairs (VA) healthcare system from 11/12/2020 to 25/03/2021 using combined VA and Medicare electronic health records. We identified the best matching mRNA-1273 recipient(s) for each BNT162b2 recipient, using exact/coarsened-exact matching (calendar week, VA integrated service network, age buckets and Charlson comorbidity index buckets) followed by propensity score matching. Vaccine recipients were followed from the date of first vaccine dose until 25/08/2021 for the development of SARS-CoV-2 infection, SARS-CoV-2-related hospitalization or SARS-CoV-2-related death. Findings: Each group included 902,235 well-matched vaccine recipients, followed for a mean of 192 days, during which 16,890 SARS-CoV-2 infections, 3591 SARS-CoV-2-related hospitalizations and 381 SARS-CoV-2-related deaths were documented. Compared to BNT162b2, mRNA-1273 recipients had significantly lower risk of SARS-CoV-2 infection (adjusted hazard ratio [aHR] 0.736, 95% CI 0.696-0.779) and SARS-CoV-2-related hospitalization (aHR 0.633, 95% CI 0.562-0.713), which persisted across all age groups, comorbidity burden categories and black/white race. The differences between mRNA-1273 and BNT162b2 in risk of infection or hospitalization were progressively greater when the follow-up period was longer, i.e. extending to March 31, June 30 or August 25, 2021. These differences were more pronounced when we analyzed separately the outcomes that occurred during the follow-up period from July 1 to August 25, 2021 when the Delta variant became predominant in the U.S. (aHR for infection 0.584, 95% CI 0.533-0.639 and aHR for hospitalization 0.387, 95% 0.311-0.482). SARS-CoV-2-related deaths were less common in mRNA-1273 versus BNT162b2 recipients (168 versus 213) but this difference was not statistically significant (aHR 0.808, 95% CI 0.592-1.103). Interpretation: In conclusion, although absolute rates of infection, hospitalization and death in both vaccine groups were low regardless of the vaccine received, our data suggests that compared to BNT162b2, vaccination with mRNA-1273 resulted in significantly lower rates of SARS-CoV-2-infection and SARS-CoV-2-related hospitalization. These differences were greater with longer follow-up time since vaccination and even more pronounced in the Delta variant era. Funding: U.S. Department of Veterans Affairs, grant numbers COVID19-8900-11 and C19 21-278.

Mechanistic Studies and Formulation Mitigations of Adeno-associated Virus Capsid Rupture During Freezing and Thawing: Mechanisms of Freeze/Thaw Induced AAV Rupture.

Gene therapies delivered using adeno-associated virus (AAV) vectors are showing promise for many diseases. Frozen AAV drug products are exposed to freeze-thaw (F/T) cycles during manufacturing, storage, and distribution. In this work we studied the mechanisms of AAV capsid rupture during F/T. We found that exposure to interfaces, exacerbated by F/T, and the mechanical force of excipient devitrification correlated with AAV capsid rupture during F/T. There was no impact of pH shifts, cryo-concentration, or cold-denaturation. Results were similar for AAV8 and AAV9. With these mechanistic insights we identified three formulation mitigation approaches. Addition of ≥0.0005% w/v poloxamer 188 (P188) eliminated substantial recovery losses (up to ∼60% without P188) and minimized rupture to ≤1% per F/T cycle. Elimination of exothermic devitrification events during rewarming, either by formulating with a low buffer concentration, or by adding a cryoprotectant further reduced rupture during F/T. Rupture of AAV9 was <0.2% per F/T cycle in a formulation with 1 mM phosphate, 4.4 mM dextrose, electrolytes, and 0.001% P188 at pH 7.2. Rupture of AAV8 was not detected when formulated with 4% sucrose, 100 mM salt, and 0.001% P188 at pH 7.4. These results provide insights into effective strategies for stabilizing AAVs against rupture during F/T.