Statin treatment and mortality: propensity score-matched analyses of 2007-2008 and 2009-2010 laboratory-confirmed influenza hospitalizations

Antiviral Potential of Natural Resources against Influenza Virus Infections

Influenza is a severe contagious disease caused by influenza A and B viruses. The WHO estimates that annual outbreaks lead to 3-5 million severe infections of which approximately 10% lead to the death of the patient. While vaccination is the cornerstone of prevention, antiviral drugs represent the most important treatment option of acute infections. Only two classes of drugs are currently approved for the treatment of influenza in numerous countries: M2 channel blockers and neuraminidase inhibitors. In some countries, additional compounds such as the recently developed cap-dependent endonuclease inhibitor baloxavir marboxil or the polymerase inhibitor favipiravir are available. However, many of these compounds suffer from poor efficacy, if not applied early after infection. Furthermore, many influenza strains have developed resistances and lost susceptibility to these compounds. As a result, there is an urgent need to develop new anti-influenza drugs against a broad spectrum of subtypes. Natural products have made an important contribution to the development of new lead structures, particularly in the field of infectious diseases. Therefore, this article aims to review the research on the identification of novel lead structures isolated from natural resources suitable to treat influenza infections.

Atorvastatin for reduction of 28-day mortality in hospitalized COVID-19 patients: study protocol for a randomized, double-blinded, placebo-controlled, clinical trial

Background

Although mass vaccination has reduced the severity of COVID-19, mortality is still high among hospitalized patients. Being a sepsis-like disease, an anti-inflammatory drug as atorvastatin would reduce mortality and severity in COVID-19.

Methods

We designed a randomized clinical trial that recruited 220 COVID-19 patients admitted in the COVID-19 isolation hospital at Mansoura University, Egypt. One hundred ten cases were assigned to receive 40 mg atorvastatin once daily for 28 days, and 110 were assigned to receive placebo. Delta Pharm company supported the study with the drug and the placebo, which mimics the drug as regards the drug package, the tablet color, consistency, and size. All patients received the standard treatment as per the hospital protocol. The Institutional Review Board approval and the informed consent from all participants were obtained.

The primary outcome is the 28-day all-cause mortality. Additionally, we will collect the in-hospital mortality, the need for mechanical ventilation, time to clinical improvement, in-hospital thrombo-embolic events, acute kidney injury, and the hospital and the intensive care duration of stay. We plan to follow the patients up for 6 months for reporting mortality and long-term neurological, psychological, and respiratory consequences.

We will report the un-adjusted 28-mortality using χ². Then, we will report the adjusted odds ratio with a pre-planned multiple logistic regression model. We will report our results using the point estimate and the 95% confidence interval and the P-value.

Discussion

The additional issue that we would like to discuss is the added workload on the clinicians and the allied healthcare workers who performed research at the time of the pandemic. Therefore, doing research at the pandemic era was, indeed, challenging.

Trial registration

The study was registered at the Clinical Trial Registry (NCT04952350) on July 1st, 2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06619-9.

Best Practice Guidelines for Propensity Score Methods in Medical Research: Consideration on Theory, Implementation, and Reporting. A Review

Rigorous and reproducible methodology of controlling for bias is essential for high-quality, evidence-based studies. Propensity score matching (PSM) is a valuable way to control for bias and achieve pseudo-randomization in retrospective observation studies. The purpose of this review is to 1) provide a clear conceptual framework for PSM, 2) recommend how to best report its use in studies, and 3) offer some practical examples of implementation. First, this article covers the concepts behind PSM, discusses its pros and cons, and compares it with other methods of controlling for bias, namely, hard/exact matching and regression analysis. Second, recommendations are given for what to report in a manuscript when PSM is used. Finally, a worked example is provided, which can also serve as a template for the reader's own studies. A study's conclusions are only as strong as its methods. PSM is an invaluable tool for producing rigorous and reproducible results in observational studies. The goal of this article is to give practicing clinical physicians not only a better understanding of PSM and its implications but the ability to implement it for their own studies. STUDY DESIGN: Review.

Promising drug repurposing approach targeted for cytokine storm implicated in SARS-CoV-2 complications

A global threat has emerged in 2019 due to the rapid spread of Coronavirus disease (COVID-19). As of January 2021, the number of cases worldwide reached 103 million cases and 2.22 million deaths which were confirmed as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This global pandemic galvanized the scientific community to study the causative virus (SARS-CoV2) pathogenesis, transmission, and clinical symptoms. Remarkably, the most common complication associated with this disease is the cytokine storm which is responsible for COVID-19 mortality. Thus, targeting the cytokine storm with new medications is needed to hamper COVID-19 complications where the most prominent strategy for the treatment is drug repurposing. Through this strategy, several steps are skipped especially those required for testing drug safety and thus may help in reducing the dissemination of this pandemic. Accordingly, the aim of this review is to outline the pathogenesis, clinical features, and immune complications of SARS-CoV2 in addition to suggesting several repurposed drugs with their plausible mechanism of action for possible management of severe COVID-19 cases.

In-hospital use of statins is associated with a reduced risk of mortality in coronavirus-2019 (COVID-19): systematic review and meta-analysis

BACKGROUND AND AIMS

The idea of treating COVID-19 with statins is biologically plausible, although it is still controversial. The systematic review and meta-analysis aimed to address the association between the use of statins and risk of mortality in patients with COVID-19.

METHODS

Several electronic databases, including PubMed, SCOPUS, EuropePMC, and the Cochrane Central Register of Controlled Trials, with relevant keywords up to 11 November 2020, were used to perform a systematic literature search. This study included research papers containing samples of adult COVID-19 patients who had data on statin use and recorded mortality as their outcome of interest. Risk estimates of mortality in statin users versus non-statin users were pooled across studies using inverse-variance weighted DerSimonian-Laird random-effect models.

RESULTS

Thirteen studies with a total of 52,122 patients were included in the final qualitative and quantitative analysis. Eight studies reported in-hospital use of statins; meanwhile, the remaining studies reported pre-admission use of statins. In-hospital use of statin was associated with a reduced risk of mortality (RR 0.54, 95% CI 0.50-0.58, p < 0.00001; I2: 0%, p = 0.87), while pre-admission use of statin was not associated with mortality (RR 1.18, 95% CI 0.79-1.77, p = 0.415; I2: 68.6%, p = 0.013). The funnel plot for the association between the use of statins and mortality were asymmetrical.

CONCLUSION

This meta-analysis showed that in-hospital use of statins was associated with a reduced risk of mortality in patients with COVID-19.

Perspective Adjunctive Therapies for COVID-19: Beyond Antiviral Therapy

The coronavirus disease 2019 (COVID-19) pandemic is the largest health crisis ever faced worldwide. It has resulted in great health and economic costs because no effective treatment is currently available. Since infected persons vary in presentation from healthy asymptomatic mild symptoms to those who need intensive care support and eventually succumb to the disease, this illness is considered to depend primarily on individual immunity. Demographic distribution and disease severity in several regions of the world vary; therefore, it is believed that natural inherent immunity provided through dietary sources and traditional medicines could play an important role in infection prevention and disease progression. People can boost their immunity to prevent them from infection after COVID-19 exposure and can reduce their inflammatory reactions to protect their organ deterioration in case suffering from the disease. Some drugs with in-situ immunomodulatory and anti-inflammatory activity are also identified as adjunctive therapy in the COVID-19 era. This review discusses the importance of COVID-19 interactions with immune cells and inflammatory cells; and further emphasizes the possible pathways related with traditional herbs, medications and nutritional products. We believe that such pathophysiological pathway approach treatment is rational and important for future development of new therapeutic agents for prevention or cure of COVID-19 infection.

EFFECT oF STATIN THERAPY oN SARS-CoV-2 INFECTION-RELATED

Aim

Assessing the effect of statin therapy at hospital admission for COVID-19 on in-hospital mortality.

Methods and Results

Retrospective observational study. Patients taking statins were 11 years older and had significantly more comorbidities than patients who were not taking statins. A genetic matching (GM) procedure was performed prior to analysis of the mortality risk. A Cox proportional hazards model was used for the cause-specific hazard (CSH) function, and a competing-risks Fine and Gray (FG) model was also used to study the direct effects of statins on risk.

Data from reverse transcription-polymerase chain reaction-confirmed 2157 SARS-CoV-2-infected patients (1234 men, 923 women; age: 67 y/o (IQR 54-78)) admitted to the hospital were retrieved from the clinical records in anonymized manner. 353 deaths occurred. 581 patients were taking statins. Univariate test after GM showed a significantly lower mortality rate in patients on statin therapy than the matched non-statin group (19.8% vs. 25.4%, χ² with Yates continuity correction: p = 0.027). The mortality rate was even lower in patients (n = 336) who maintained their statin treatments during hospitalization compared to the GM non-statin group (17.4%; p = 0.045). The Cox model applied to the CSH function (HR = 0.58(CI: 0.39-0.89); p = 0.01) and the competing risks FG model (HR = 0.60(CI: 0.39-0.92); p = 0.02) suggest that statins are associated with reduced COVID-19-related mortality.

Conclusions

A lower SARS-CoV-2 infection-related mortality was observed in patients treated with statin therapy prior to hospitalization. Statin therapy should not be discontinued due to the global concern of the pandemic or in patients hospitalized for COVID-19.

Early clinical factors predicting the development of critical disease in Japanese patients with COVID-19: A single-center, retrospective, observational study

The factors predicting the progression of coronavirus disease‐2019 (COVID‐19) from mild to moderate to critical are unclear. We retrospectively evaluated risk factors for disease progression in Japanese patients with COVID‐19. Seventy‐four patients with laboratory‐confirmed COVID‐19 were hospitalized in our hospital between February 20, 2020, and June 10, 2020. We excluded asymptomatic, non‐Japanese, and pediatric patients. We divided patients into the stable group and the progression group (PG; requiring mechanical ventilation). We compared the clinical factors. We established the cutoff values (COVs) for significantly different factors via receiver operating characteristic curve analysis and identified risk factors by univariate regression. We enrolled 57 patients with COVID‐19 (median age 52 years, 56.1% male). The median time from symptom onset to admission was 8 days. Seven patients developed critical disease (PG: 12.2%), two (3.5%) of whom died; 50 had stable disease. Univariate logistic analysis identified an elevated lactate dehydrogenase (LDH) level (COV: 309 U/l), a decreased estimated glomerular filtration rate (eGFR; COV: 68 ml/min), lymphocytopenia (COV: 980/μl), and statin use as significantly associated with disease progression. However, in the Cox proportional hazards analysis, lymphocytopenia at admission was not significant. We identified three candidate risk factors for progression to critical COVID‐19 in adult Japanese patients: statin use, elevated LDH level, and decreased eGFR.

To evaluate risk factors for disease progression in Japanese patients with COVID‐19, we examined seventy‐four patients with laboratory‐confirmed COVID‐19.

Seven patients (12.2%) developed critical disease requiring mechanical ventilation, two (3.5%) of whom died.

We identified three candidate risk factors for progression to critical COVID‐19 in adult Japanese patients: statin use elevated LDH level and decreased eGFR.

Seasonal and pandemic influenza: 100 years of progress, still much to learn

Influenza viruses are highly transmissible, both within and between host species. The severity of the disease they cause is highly variable, from the mild and inapparent through to the devastating and fatal. The unpredictability of epidemic and pandemic outbreaks is accompanied but the predictability of seasonal disease in wide areas of the Globe, providing an inexorable toll on human health and survival. Although there have been great improvements in understanding influenza viruses and the disease that they cause, our knowledge of the effects they have on the host and the ways that the host immune system responds continues to develop. This review highlights the importance of the mucosa in defence against infection and in understanding the pathogenesis of disease. Although vaccines have been available for many decades, they remain suboptimal in needing constant redesign and in only providing short-term protection. There are real prospects for improvement in treatment and prevention of influenza soon, based on deeper knowledge of how the virus transmits, replicates and triggers immune defences at the mucosal surface.

Potential role of statins in COVID-19

Patients with COVID-19 infection have an increased risk of cardiovascular complications and thrombotic events. Statins are known for their pleiotropic anti-inflammatory, antithrombotic and immunomodulatory effects. They may have a potential role as adjunctive therapy to mitigate endothelial dysfunction and dysregulated inflammation in patients with COVID-19 infection.

Statins and outcomes of hospitalized patients with laboratory-confirmed 2017-2018 influenza

No studies evaluating the association between statins and outcomes of patients with seasonal influenza have been performed since the 2007-2008 and the 2009 pandemic H1N1 influenza seasons. All consecutive hospitalized patients between October 2017 and April 2018, diagnosed with laboratory-confirmed influenza A and B virus, were included. Patients were divided into two groups: statin and non-statin users. Outcomes were 30- and 90-day mortality, complications (pneumonia, myocarditis, encephalitis, intensive care unit (ICU) transfer, mechanical ventilation, vasopressor support), length of hospital stay, and readmission rates. A multivariate analysis was performed to adjust for mortality risk factors. To compare the groups, we matched patients to the nearest neighbor propensity score. Of the 526 patients ill with influenza A (201/526) and B (325/526), 36% (188/526) were statin users; 64% (338/526) were not. Statin users were older (78 vs.70; p = < 0.05) and suffered from more comorbidities (Charlson comorbidity scores of 6 vs.4; p < 0.005). The 30-day mortality rate among statin vs. non-statin users was 6% vs. 8% (p = 0.3). On multivariate analysis, statin use was not associated with mortality benefit (OR = 0.67 (0.29-1.36)). After propensity score matching, the results were unchanged (OR = 0.71 (0.29-1.71)). Statin users were diagnosed with less complicated diseases as they were less likely to receive vasopressor support, mechanical ventilation, and/or transfer to the ICU. Although statin users were significantly older and exhibited more comorbidities, 30-day mortality rates did not differ between statin users and non-users, which may signify a protective role of statins on seasonal influenza patients. Further studies performed during different influenza seasons and different subtypes are essential.

Statin Use and Risks of Influenza-Related Outcomes Among Older Adults Receiving Standard-Dose or High-Dose Influenza Vaccines Through Medicare During 2010-2015

Background

Statins are used to reduce cardiovascular disease risk. Recent studies suggest that statin use may be associated with an increased influenza risk among influenza vaccinees. We used Medicare data to evaluate associations between statins and risks of influenza-related encounters among vaccinees.

Methods

In this retrospective cohort study, we identified Medicare beneficiaries aged > 65 years who received high-dose (HD) or standard-dose (SD) influenza vaccines at pharmacies from 2010-2011 through 2014-2015. Statin users were matched to nonusers by vaccine type, demographics, prior medical encounters, and comorbidities. We used multivariable Poisson models to estimate associations between statin use around the time of vaccination and risk of influenza-related encounters. Study outcomes included influenza-related office visits with a rapid test followed by dispensing of oseltamivir and influenza-related hospitalizations (including emergency room visits) during high influenza circulation periods.

Results

The study included 1403651 statin users matched to nonusers. Cohorts were well balanced, with standardized mean differences ≤0.03 for all measured covariates. For statin users compared to nonusers, the adjusted relative risk was 1.086 (95% confidence interval [CI], 1.025-1.150) for influenza-related visits and 1.096 (95% CI, 1.013-1.185) for influenza-related hospitalizations. The risk difference ranged from ‒0.02 to 0.23 for influenza-related visits and from ‒0.04 to 0.13 for hospitalizations, depending on season severity. Results were similar for HD and SD vaccinees and for nonsynthetic and synthetic statin users.

Conclusions

Among 2.8 million Medicare beneficiaries, these results suggest that statin use around the time of vaccination does not substantially affect the risk of influenza-related medical encounters among older adults.

Clinician-initiated research on treating the host response to pandemic influenza

To prepare for the next influenza pandemic and other emerging virus diseases, scientists and health officials are focused on developing new vaccines and treatments that target these viruses. Ideally, these interventions could be highly effective, but for many practical reasons these "top down" efforts are unlikely to provide clinicians with what they will need to manage their patients. As a "bottom up" alternative, combinations of generic drugs like statins and angiotensin receptor blockers (ARBs) might be used to treat the host response to infection. These drugs counteract endothelial dysfunction, a central abnormality in these diseases. Observational studies in patients with influenza, pneumonia, sepsis and Ebola suggest they might work. During the 1918 influenza pandemic, children were infected more frequently than adults, but their mortality rate was much lower. Their survival was probably due to better tolerance (reduced pathogen damage), not greater resistance (reduced pathogen burden). The same pattern of susceptibility characterizes other infectious diseases, and it probably reflects the heritage of human evolution. Drugs like statins and ARBs can metabolically reprogram the host response and improve tolerance to infection. Treating the host response is not on the research agendas of international agencies responsible for pandemic preparedness. Consequently, clinicians might have to undertake clinical trials in patients hospitalised with seasonal influenza, pneumonia and sepsis in order to show convincingly whether treating the host response would work. Most candidate generic drugs are inexpensive, widely available, known to be safe and used by clinicians every day. Demonstrating their efficacy would mean that patients in all countries would have access to treatment on the first pandemic or epidemic day.

The role of adjuvant immunomodulatory agents for treatment of severe influenza

A severe inflammatory immune response with hypercytokinemia occurs in patients hospitalized with severe influenza, such as avian influenza A(H5N1), A(H7N9), and seasonal A(H1N1)pdm09 virus infections. The role of immunomodulatory therapy is unclear as there have been limited published data based on randomized controlled trials (RCTs). Passive immunotherapy such as convalescent plasma and hyperimmune globulin have some studies demonstrating benefit when administered as an adjunctive therapy for severe influenza. Triple combination of oseltamivir, clarithromycin, and naproxen for severe influenza has one study supporting its use, and confirmatory studies would be of great interest. Likewise, confirmatory studies of sirolimus without concomitant corticosteroid therapy should be explored as a research priority. Other agents with potential immunomodulating effects, including non-immune intravenous immunoglobulin, N-acetylcysteine, acute use of statins, macrolides, pamidronate, nitazoxanide, chloroquine, antiC5a antibody, interferons, human mesenchymal stromal cells, mycophenolic acid, peroxisome proliferator-activated receptors agonists, non-steroidal anti-inflammatory agents, mesalazine, herbal medicine, and the role of plasmapheresis and hemoperfusion as rescue therapy have supportive preclinical or observational clinical data, and deserve more investigation preferably by RCTs. Systemic corticosteroids administered in high dose may increase the risk of mortality and morbidity in patients with severe influenza and should not be used, while the clinical utility of low dose systemic corticosteroids requires further investigation.

Skin immunization by microneedle patch overcomes statin-induced suppression of immune responses to influenza vaccine

Recent studies indicated that in elderly individuals, statin therapy is associated with a reduced response to influenza vaccination. The present study was designed to determine effects on the immune response to influenza vaccination induced by statin administration in a mouse model, and investigate potential approaches to improve the outcome of vaccination on the background of statin therapy. We fed middle aged BALB/c mice a high fat “western” diet (WD) alone or supplemented with atorvastatin (AT) for 14 weeks, and control mice were fed with the regular rodent diet. Mice were immunized with a single dose of subunit A/Brisbane/59/07 (H1N1) vaccine, either systemically or with dissolving microneedle patches (MNPs). We observed that a greater age-dependent decline in the hemagglutinin inhibition titers occurred in systemically-immunized mice than in MNP- immunized mice. AT dampened the antibody response in the animals vaccinated by either route of vaccine delivery. However, the MNP-vaccinated AT-treated animals had ~20 times higher total antibody levels to the influenza vaccine than the systemically vaccinated group one month postvaccination. We propose that microneedle vaccination against influenza provides an approach to ameliorate the immunosuppressive effect of statin therapy observed with systemic immunization.

Host-directed therapies for bacterial and viral infections

Host-directed therapy (HDT) is a novel approach in the field of anti-infectives for overcoming antimicrobial resistance.

HDT aims to interfere with host cell factors that are required by a pathogen for replication or persistence, to enhance protective immune responses against a pathogen, to reduce exacerbated inflammation and to balance immune reactivity at sites of pathology.

HDTs encompassing the 'shock and kill' strategy or the delivery of recombinant interferons are possible approaches to treat HIV infections. HDTs that suppress the cytokine storm that is induced by some acute viral infections represent a promising concept.

In tuberculosis, HDT aims to enhance the antimicrobial activities of phagocytes through phagosomal maturation, autophagy and antimicrobial peptides. HDTs also curtail inflammation through interference with soluble (such as eicosanoids or cytokines) or cellular (co-stimulatory molecules) factors and modulate granulomas to allow the access of antimicrobials or to restrict tissue damage.

Numerous parallels between the immunological abnormalities that occur in sepsis and cancer indicate that the HDTs that are effective in oncology may also hold promise in sepsis.

Advances in immune phenotyping, genetic screening and biosignatures will help to guide drug therapy to optimize the host response. Combinations of canonical pathogen-directed drugs and novel HDTs will become indispensable in treating emerging infections and diseases caused by drug-resistant pathogens.

Host-directed therapy (HDT) aims to interfere with host cell factors that are required by a pathogen for replication or persistence. In this Review, Kaufmannet al. describe recent progress in the development of HDTs for the treatment of viral and bacterial infections and the challenges in bringing these approaches to the clinic.

Despite the recent increase in the development of antivirals and antibiotics, antimicrobial resistance and the lack of broad-spectrum virus-targeting drugs are still important issues and additional alternative approaches to treat infectious diseases are urgently needed. Host-directed therapy (HDT) is an emerging approach in the field of anti-infectives. The strategy behind HDT is to interfere with host cell factors that are required by a pathogen for replication or persistence, to enhance protective immune responses against a pathogen, to reduce exacerbated inflammation and to balance immune reactivity at sites of pathology. Although HDTs encompassing interferons are well established for the treatment of chronic viral hepatitis, novel strategies aimed at the functional cure of persistent viral infections and the development of broad-spectrum antivirals against emerging viruses seem to be crucial. In chronic bacterial infections, such as tuberculosis, HDT strategies aim to enhance the antimicrobial activities of phagocytes and to curtail inflammation through interference with soluble factors (such as eicosanoids and cytokines) or cellular factors (such as co-stimulatory molecules). This Review describes current progress in the development of HDTs for viral and bacterial infections, including sepsis, and the challenges in bringing these new approaches to the clinic.

Treating the host response to emerging virus diseases: lessons learned from sepsis, pneumonia, influenza and Ebola

There is an ongoing threat of epidemic or pandemic diseases that could be caused by influenza, Ebola or other emerging viruses. It will be difficult and costly to develop new drugs that target each of these viruses. Statins and angiotensin receptor blockers (ARBs) have been effective in treating patients with sepsis, pneumonia and influenza, and a statin/ARB combination appeared to dramatically reduce mortality during the recent Ebola outbreak. These drugs target (among other things) the endothelial dysfunction found in all of these diseases. Most scientists work on new drugs that target viruses, and few accept the idea of treating the host response with generic drugs. A great deal of research will be needed to show conclusively that these drugs work, and this will require the support of public agencies and foundations. Investigators in developing countries should take an active role in this research. If the next Public Health Emergency of International Concern is caused by an emerging virus, a "top down" approach to developing specific new drug treatments is unlikely to be effective. However, a "bottom up" approach to treatment that targets the host response to these viruses by using widely available and inexpensive generic drugs could reduce mortality in any country with a basic health care system. In doing so, it would make an immeasurable contribution to global equity and global security.