Renin-Angiotensin System Pathway Therapeutics Associated With Improved Outcomes in Males Hospitalized With COVID-19

Complex Thrombo-Inflammatory Responses versus Outcomes of Non-COVID-19 Community-Acquired Pneumonia and COVID-19

INTRODUCTION

The thrombo-inflammatory response and outcomes of community-acquired pneumonia (CAP) due to various organisms (non-COVID-19 CAP) versus CAP due to a single virus, SARS-CoV-2 (i.e., COVID-19) may differ.

METHODS

Adults hospitalized with non-COVID-19 CAP (December 1, 2021-June 15, 2023) or COVID-19 (March 2, 2020-June 15, 2023) in Canada. We compared non-COVID-19 CAP and COVID-19 baseline, thrombo-inflammatory response, and mortality. We measured plasma cytokine and coagulation factor levels in a sample of patients, did hierarchical clustering, and compared cytokine and coagulation factor levels.

RESULTS

In 2,485 patients (non-COVID-19 CAP, n = 719; COVID-19 patients, n = 2,157), non-COVID-19 CAP patients had significantly lower 28-day mortality (CAP vs. COVID-19 waves 1 and 2; 10% vs. 18% and 16%, respectively), intensive care unit admission (CAP vs. all waves; 15% vs. 39%, 37%, 33%, and 24%, respectively), invasive ventilation (CAP vs. waves 1, 2, and 3 patients; 11% vs. 25%, 20%, and 16%), vasopressor use (CAP 12% vs. 23%, 21%, and 18%), and renal replacement therapy use (CAP 3% vs. Omicron 7%). Complexity of hierarchical clustering aligned directly with mortality: COVID-19 wave 1 and 2 patients had six clusters at admission and higher mortality than non-COVID-19 CAP and Omicron that had three clusters at admission. Pooling all COVID-19 waves increased complexity with seven clusters on admission.

CONCLUSION

Complex thrombo-inflammatory responses aligned with mortality of CAP. At a fundamental level, the human thrombo-inflammatory response to a brand new virus was "confused" whereas humans had eons of time to develop a more concise efficient thrombo-inflammatory host response to CAP.

Insertion/deletion (I/D) polymorphisms of angiotensin-converting enzyme gene and their implications for susceptibility and severity of COVID-19: A systematic review and meta-analysis

The insertion or deletion polymorphisms of the angiotensin-converting enzyme gene (ACE I/D) have been the subject of significant research related to coronavirus disease 2019 (COVID-19). Despite this, the findings have remained uncertain and debatable. The aim of this study was to determine the associations between the ACE I/D polymorphisms and the susceptibility as well as the severity of COVID-19. A meta-analysis study (PROSPERO: CRD42022384562) was conducted by searching the articles published on PubMed, Scopus, and Embase as of May 15, 2023. Information regarding the impact of ACE I/D variant on the susceptibility to COVID-19 and its severity was collected and analyzed utilizing the Mantel-Haenszel method with a random effects model or fixed effects model, depending on the presence or absence of heterogeneity. Out of 3,335 articles, 21 articles were included, of which 13 investigated the association between ACE I/D and the risk of COVID-19 infection and 18 of them examined its influence on disease severity. The D allele of ACE increased risk of COVID-19 infection (OR: 1.41; 95%CI: 1.08-1.85; p-Egger: 0.0676; p-Heterogeneity: <0.001; p=0.0120), while ACE I allele (OR: 0.71; 95%CI: 0.54-0.93; p-Egger: 0.0676; p-Heterogeneity: <0.001; p=0.012) and II genotype (OR: 0.55; 95%CI: 0.34-0.87; p-Egger: 0.200; p-Heterogeneity: <0.001; p=0.011) decreased the risk of infection. Additionally, there was a notable association between the ACE ID genotype and an elevated likelihood of experiencing severe COVID-19 within the Asian population (OR: 1.46; 95%CI: 1.15-1.84; p-Egger: 0.092; p-Heterogeneity: 0.116; p=0.002). The presence of ACE I/D polymorphisms significantly influences the likelihood of being susceptible to and experiencing the severity of COVID-19.

Community versus academic hospital community-acquired pneumonia patients: a nested cohort study

BACKGROUND

Most Canadians receive their care in community hospitals, yet most clinical research is conducted in academic hospitals. This study aims to compare patients with community acquired pneumonia (CAP) treated in academic and community hospitals with respect to their demographics, clinical characteristics, treatments and outcomes.

METHODS

This nested observational cohort substudy of the Community Acquired Pneumonia: Toward InnoVAtive Treatment (CAPTIVATE) trial included 1,329 hospitalized adults with CAP recruited between March 1st, 2018 and September 31st, 2023 from 15 Canadian hospitals. Unadjusted and adjusted analyses for age, sex and co-morbidities using logistic, Cox and censored quantile regressions were conducted.

RESULTS

Patients in community hospitals were older (mean [SD] 75.0 [15.7] years vs. 68.3 [16.2] years; p < 0.001), were more likely to be female (49.7% vs. 41.0%, p = 0.002), and had more comorbidities (75.9% vs. 64.8%, p < 0.001). More patients in community hospitals received corticosteroids (49.2% vs. 37.4%, p < 0.001). Community hospital patients had a higher likelihood of developing acute respiratory distress syndrome (OR 3.13, 95% CI: 1.87, 5.24, p = < 0.001), and acute cardiac injury (OR 2.53, 95% CI: 1.33, 4.83, p = 0.005). In unadjusted and adjusted analyses, 28-day mortality difference did not meet statistical significance (OR 1.43, 95% CI: 0.98, 20.7, p = 0.062 and OR 1.23, 95% CI: 0.81, 1.87, p = 0.332, respective).

CONCLUSION

Patients with CAP in Canadian community and academic hospitals differed with respect to their age, clinical characteristics, treatments and outcomes, emphasizing the importance of including more community hospitals in clinical research studies to ensure the generalizability of results.

Atorvastatin and telmisartan do not reduce nasopharyngeal carriage of SARS-CoV-2 in mild or moderate COVID-19 in a phase IIb randomized controlled trial

Observational studies suggest a reduction in fatal or severe COVID-19 disease with the use of ACE2 inhibitors and statins. We implemented a randomized controlled tree-arm open label trial evaluating the benefits of adding telmisartan (TLM) or atorvastatin (ATV) to lopinavir boosted ritonavir (LPVr) on the SARS-CoV-2 nasopharyngeal viral load in patients with mild / moderate COVID-19 infection in Côte d'Ivoire. RT-PCR positive COVID-19 patients ≥ 18 years, with general or respiratory symptoms for less than 7 days were randomized (1:1:1) to receive LPVr (400 mg/100 mg twice daily), LPVr + TLM (10 mg once daily) or LPVr + ATV (20 mg once daily) for 10 days. The primary endpoint was viro-inflammatory success defined as a composite variable at day 11: Ct ≥ 40 and C-reactive protein < 27 mg/L. We randomized 294 patients: 96 to LPVr, 100 to LPVr + TLM, 98 to LPVr + ATV arms. Baseline characteristics were well balanced between arms. In the primary analysis (missing = failure), 46% patients in the LPVr arm reached viro-inflammatory success at day 11 vs 43% in the LPVr + TLM arm (p = 0.69) and 43% in the LPVr + ATV arm (p = 0.68). The median time from baseline to resolution of COVID-19 related symptoms was not different between arms. Nine patients were hospitalized: 2 in the LPVr arm, 5 in the LPVr + TLM arm and 2 in the LPVr + ATV arm and 4 patients died. Among adults with mild to moderate COVID-19 infection, the addition of telmisartan or atorvastatin, to the standard LPVr treatment is not associated with a better virological or clinical outcome.Trial registration: NCT04466241, registered on 10/07/2020.

Effects of Losartan on Patients Hospitalized for Acute COVID-19: A Randomized Controlled Trial

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) down-regulates angiotensin-converting enzyme 2, potentially increasing angiotensin II. We hypothesized that losartan compared to usual care decreases mortality and is safe in patients hospitalized with coronavirus disease 2019 (COVID-19). We aimed to evaluate the effect of losartan versus usual care on 28-day mortality in patients hospitalized for acute COVID-19.

METHODS

Eligibility criteria included adults admitted for acute COVID-19. Exclusion criteria were hypotension, hyperkalemia, acute kidney injury, and use of angiotensin receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors within 7 days. Participants were randomized to losartan 25-100 mg/day orally for the hospital duration or 3 months or the control arm (usual care) in 29 hospitals in Canada and France. The primary outcome was 28-day mortality. Secondary outcomes were hospital mortality, organ support, and serious adverse events (SAEs).

RESULTS

The trial was stopped early because of a serious safety concern with losartan. In 341 patients, any SAE and hypotension were significantly higher in the losartan versus usual care groups (any SAE: 39.8% vs 27.2%, respectively, P = .01; hypotension: 30.4% vs 15.3%, respectively, P < .001) in both ward and intensive care patients. The 28-day mortality did not differ between losartan (6.5%) versus usual care (5.9%) (odds ratio, 1.11 [95% confidence interval, .47-2.64]; P = .81), nor did organ dysfunction or secondary outcomes.

CONCLUSIONS

Caution is needed in deciding which patients to start or continue using ARBs in patients hospitalized with pneumonia to mitigate risk of hypotension, acute kidney injury, and other side effects. ARBs should not be added to care of patients hospitalized for acute COVID-19.

CLINICAL TRIALS REGISTRATION

NCT04606563.

Using a targeted metabolomics approach to explore differences in ARDS associated with COVID-19 compared to ARDS caused by H1N1 influenza and bacterial pneumonia

RATIONALE

Acute respiratory distress syndrome (ARDS) is a life-threatening critical care syndrome commonly associated with infections such as COVID-19, influenza, and bacterial pneumonia. Ongoing research aims to improve our understanding of ARDS, including its molecular mechanisms, individualized treatment options, and potential interventions to reduce inflammation and promote lung repair.

OBJECTIVE

To map and compare metabolic phenotypes of different infectious causes of ARDS to better understand the metabolic pathways involved in the underlying pathogenesis.

METHODS

We analyzed metabolic phenotypes of 3 ARDS cohorts caused by COVID-19, H1N1 influenza, and bacterial pneumonia compared to non-ARDS COVID-19-infected patients and ICU-ventilated controls. Targeted metabolomics was performed on plasma samples from a total of 150 patients using quantitative LC-MS/MS and DI-MS/MS analytical platforms.

RESULTS

Distinct metabolic phenotypes were detected between different infectious causes of ARDS. There were metabolomics differences between ARDSs associated with COVID-19 and H1N1, which include metabolic pathways involving taurine and hypotaurine, pyruvate, TCA cycle metabolites, lysine, and glycerophospholipids. ARDSs associated with bacterial pneumonia and COVID-19 differed in the metabolism of D-glutamine and D-glutamate, arginine, proline, histidine, and pyruvate. The metabolic profile of COVID-19 ARDS (C19/A) patients admitted to the ICU differed from COVID-19 pneumonia (C19/P) patients who were not admitted to the ICU in metabolisms of phenylalanine, tryptophan, lysine, and tyrosine. Metabolomics analysis revealed significant differences between C19/A, H1N1/A, and PNA/A vs ICU-ventilated controls, reflecting potentially different disease mechanisms.

CONCLUSION

Different metabolic phenotypes characterize ARDS associated with different viral and bacterial infections.

COVID-19 and cardiovascular disease in patients with chronic kidney disease

Millions of people worldwide have chronic kidney disease (CKD). Affected patients are at high risk for cardiovascular (CV) disease for several reasons. Among various comorbidities, CKD is associated with the more severe forms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This is particularly true for patients receiving dialysis or for kidney recipients. From the start of the SARS-CoV-2 pandemic, several CV complications have been observed in affected subjects, spanning acute inflammatory manifestations, CV events, thrombotic episodes and arrythmias. Several pathogenetic mechanisms have been hypothesized, including direct cytopathic viral effects on the myocardium, endothelial damage and hypercoagulability. This spectrum of disease can occur during the acute phase of the infection, but also months after recovery. This review is focussed on the CV complications of coronavirus disease 2019 (COVID-19) with particular interest in their implications for the CKD population.

Proteomic Evolution from Acute to Post-COVID-19 Conditions

Many COVID-19 survivors have post-COVID-19 conditions, and females are at a higher risk. We sought to determine (1) how protein levels change from acute to post-COVID-19 conditions, (2) whether females have a plasma protein signature different from that of males, and (3) which biological pathways are associated with COVID-19 when compared to restrictive lung disease. We measured protein levels in 74 patients on the day of admission and at 3 and 6 months after diagnosis. We determined protein concentrations by multiple reaction monitoring (MRM) using a panel of 269 heavy-labeled peptides. The predicted forced vital capacity (FVC) and diffusing capacity of the lungs for carbon monoxide (DLCO) were measured by routine pulmonary function testing. Proteins associated with six key lipid-related pathways increased from admission to 3 and 6 months; conversely, proteins related to innate immune responses and vasoconstriction-related proteins decreased. Multiple biological functions were regulated differentially between females and males. Concentrations of eight proteins were associated with FVC, %, and they together had c-statistics of 0.751 (CI:0.732-0.779); similarly, concentrations of five proteins had c-statistics of 0.707 (CI:0.676-0.737) for DLCO, %. Lipid biology may drive evolution from acute to post-COVID-19 conditions, while activation of innate immunity and vascular regulation pathways decreased over that period. (ProteomeXchange identifiers: PXD041762, PXD029437).

Biological sex differences in renin angiotensin system enzymes ACE and ACE2 regulate normal tissue response to radiation injury

Introduction: In experimental animal models, biological sex-differences in the manifestation and severity of normal tissue radiation injury have been well-documented. Previously we demonstrated male and female rats have differential and highly reproducible responses to high-dose partial body irradiation (PBI) with male rats having greater susceptibility to both gastrointestinal acute radiation syndrome (GI-ARS) and radiation pneumonitis than female rats. Methods: In the current study, we have investigated whether differential expression of the renin-angiotensin system (RAS) enzymes angiotensin converting enzyme (ACE) and ACE2 contribute to the observed sex-related differences in radiation response. Results: During the period of symptomatic pneumonitis, the relative ratio of ACE to ACE2 (ACE/ACE2) protein in the whole lung was significantly increased by radiation in male rats alone. Systemic treatment with small molecule ACE2 agonist diminazene aceturate (DIZE) increased lung ACE2 activity and reduced morbidity during radiation pneumonitis in both sexes. Notably DIZE treatment also abrogated morbidity in male rats during GI-ARS. We then evaluated the contribution of the irradiated bone marrow (BM) compartment on lung immune cell infiltration and ACE imbalance during pneumonitis. Transplantation of bone marrow from irradiated donors increased both ACE-expressing myeloid cell infiltration and immune ACE activity in the lung during pneumonitis compared to non-irradiated donors. Discussion: Together, these data demonstrate radiation induces a sex-dependent imbalance in the renin-angiotensin system enzymes ACE and ACE2. Additionally, these data suggest a role for ACE-expressing myeloid cells in the pathogenesis of radiation pneumonitis. Finally, the observed sex-differences underscore the need for consideration of sex as a biological variable in the development of medical countermeasures for radiation exposure.

Renin-Angiotensin System and Sex Differences in COVID-19: A Critical Assessment

The current epidemic of corona virus disease (COVID-19) has resulted in an immense health burden that became the third leading cause of death and potentially contributed to a decline in life expectancy in the United States. The severe acute respiratory syndrome-related coronavirus-2 binds to the surface-bound peptidase angiotensin-converting enzyme 2 (ACE2, EC 3.4.17.23) leading to tissue infection and viral replication. ACE2 is an important enzymatic component of the renin-angiotensin system (RAS) expressed in the lung and other organs. The peptidase regulates the levels of the peptide hormones Ang II and Ang-(1-7), which have distinct and opposing actions to one another, as well as other cardiovascular peptides. A potential consequence of severe acute respiratory syndrome-related coronavirus-2 infection is reduced ACE2 activity by internalization of the viral-ACE2 complex and subsequent activation of the RAS (higher ratio of Ang II:Ang-[1-7]) that may exacerbate the acute inflammatory events in COVID-19 patients and possibly contribute to the effects of long COVID-19. Moreover, COVID-19 patients present with an array of autoantibodies to various components of the RAS including the peptide Ang II, the enzyme ACE2, and the AT1 AT2 and Mas receptors. Greater disease severity is also evident in male COVID-19 patients, which may reflect underlying sex differences in the regulation of the 2 distinct functional arms of the RAS. The current review provides a critical evaluation of the evidence for an activated RAS in COVID-19 subjects and whether this system contributes to the greater severity of severe acute respiratory syndrome-related coronavirus-2 infection in males as compared with females.

Mini-review: Angiotensin- converting enzyme 1 (ACE1) and the impact for diseases such as Alzheimer's disease, sarcopenia, cancer, and COVID-19

Ageing has been associated with comorbidities, systemic low-grade of inflammation, and immunosenescence. Hypertension is the most common morbidity and anti-hypertensives are used for more than 50%. Angiotensin-converting enzyme 1 inhibitors (ACEi) and angiotensin II receptor blockers (ARB) control blood pressure but also seem to play a role in comorbidities such as Alzheimer's disease, sarcopenia and cancer. The impact of anti-hypertensives in comorbidities is due to the expression of renin-angiotensin system (RAS) in several tissues and body fluids. Angiotensin-converting enzyme 1 (ACE1) has been linked to oxidative stress, metabolism, and inflammation. The levels and activity of ACE1 are under genetic control and polymorphisms have been correlated with susceptibility to Alzheimer's disease. In addition, some results found that ACEi and ARB users present delayed cognitive decline and reduced risk of dementia. Regarding to sarcopenia, RAS has been linked to the catabolic and anabolic pathways for muscle mass maintenance. In some studies, older adults using ACEi were highly benefited by exercise training. In cancer, RAS and its products have been shown to play a role since their inhibition in animal models modulates tumor microenvironment and improves the delivery of chemotherapy drugs. Clinically, the incidence of colorectal cancer is reduced in patients using ACEi and ARB. During the pandemic COVID-19 it was found that ACE2 receptor plays a role in the entry of SARS-CoV-2 into the host cell. ACE1 genotypes have been linked to an increased risk for COVID-19 and severe disease. In some studies COVID-19 patients taking ARB or ACEi presented better outcome.