Implication of the emergence of the delta (B.1.617.2) variants on vaccine effectiveness.

INTRODUCTION: COVID-19 vaccines have been developed to compact the current SARS-CoV-2 pandemic and have been administered to people all over the world. These vaccines have been quite effective in reducing the possibility of severe illness, hospitalization and death. However, the recent emergence of Variants of Concern specifically the delta variant, B.1.617.2, had resulted in additional waves of the pandemic. METHODS: We aim to review the literature to understand the transmission and disease severity, and determine the efficacy of the current COVID-19 vaccines. We searched Pubmed, Scopus, and Embase till August 4th 2021, and used the search terms "delta variant", "vaccinations"," breakthrough infections", and "neutralizing antibody". For the meta-analysis, 21 studies were screened in particular and five articles (148,071 cases) were included in the study, and only four were analyzed in the meta-analysis. RESULTS: In this review, both in vitro and in vivo studies showed significant reductions in neutralization rates against delta variants for vaccinated individuals and convalescent patients with prior history of COVID-19. However, There was a lower incidence of infection with SARS-CoV-2 due to Delta variant was found after the second dose of Pfizer-BioNTech, Oxford-AstraZeneca and Moderna vaccines. CONCLUSION: In fully vaccinated individuals, symptomatic infection with the delta variant was significantly reduced, and therefore, vaccinations play an important role to assist the fight against delta variant.

Updates on Measles Incidence and Eradication: Emphasis on the Immunological Aspects of Measles Infection.

Measles is an RNA virus infectious disease mainly seen in children. Despite the availability of an effective vaccine against measles, it remains a health issue in children. Although it is a self-limiting disease, it becomes severe in undernourished and immune-compromised individuals. Measles infection is associated with secondary infections by opportunistic bacteria due to the immunosuppressive effects of the measles virus. Recent reports highlight that measles infection erases the already existing immune memory of various pathogens. This review covers the incidence, pathogenesis, measles variants, clinical presentations, secondary infections, elimination of measles virus on a global scale, and especially the immune responses related to measles infection.

Efficacy and safety of the band and slough technique for endoscopic therapy of nonampullary duodenal adenomas: a case series.

BACKGROUND: Endoscopic resection of nonampullary duodenal adenomas (NADAs) is effective but carries substantial procedural risks. Therapeutic banding for treatment of duodenal mucosal neoplasia has not been studied. We report a novel band and slough (BAS) technique for therapy of NADA without endoscopic resection. OBJECTIVE: Efficacy and safety of BAS. DESIGN: Retrospective review of a prospective database. SETTING: Community hospital. PATIENTS: Patients with sporadic and familial biopsy-proven NADA without invasive cancer undergoing BAS. INTERVENTION: Patients were treated with BAS without endoscopic resection on an outpatient basis. A follow-up telephone call was made by a nurse at 24 hours. Follow-up endoscopy was performed at 8 weeks, with further therapy of residual NADA. In patients with minimal residual NADA not amenable to banding, argon plasma coagulation (APC) "touch-up" was used. Subsequent endoscopic surveillance was performed. MAIN OUTCOME MEASUREMENTS: Complete histologic remission of NADA after successful BAS and postprocedure bleeding, perforation, and pain. RESULTS: Ten patients, average age 65 years, 6 male, with sporadic/familial adenomatous polyposis NADA 8 of 2 (6 tubular adenoma and 4 tubulovillous adenoma) were treated. Mean (largest) NADA was 12.5 mm (20 mm). Five patients achieved complete remission after a single session. Among 5 patients requiring further therapy, 3 were treated with repeat banding with or without APC and 2 with APC alone. The average number of bands per session was 4.4. Patients were followed up to 24 months without NADA recurrence. None of the patients had acute or delayed adverse events of bleeding, perforation, or postprocedure pain. LIMITATIONS: Lack of polyp tissue retrieval. CONCLUSION: BAS appears to be a safe and potentially effective endoscopic treatment for NADA. However, larger studies are needed to corroborate these findings.

COVID-19 in patients with Down syndrome: A systematic review.

INTRODUCTION: Down syndrome (DS) is associated with multiple comorbid conditions and chronic immune dysfunction. Persons with DS who contract COVID-19 are at high risk for complications and have a poor prognosis. We aimed to study the clinical symptoms, laboratory and biochemical profiles, radiologic findings, treatment, and outcomes of patients with DS and COVID-19. METHOD: We systematically searched PubMed, MEDLINE, Web of Science, Scopus, and the Cochrane Library using the keywords COVID-19 or coronavirus or SARS-CoV-2 and DS or trisomy 21. Seventeen articles were identified: eight case reports and nine case series published from December 2019 through March 2022, with a total of 55 cases. RESULTS: Patients averaged 24.8 years (26 days to 60 years); 29 of the patients were male. The most common symptoms were fever, dyspnea, and cough. Gastrointestinal and upper respiratory tract symptoms were commonly reported for pediatric patients. The most common comorbidities present in patients with DS were obesity (49.0%), hypothyroidism (21.6%) and obstructive sleep apnea (15.6%). The patients were hospitalized for a mean of 14.8 days. When the patients were compared with the general COVID-19 population, the mean number of hospitalized days was higher. Most patients had leukopenia, lymphopenia, and elevated inflammatory markers (d-dimer and C-reactive protein). Bilateral infiltrations and bilateral ground-glass opacifications were frequently seen in chest radiographs and chest computed tomographic imaging. Most of the patients were treated with methylprednisolone, macrolides, and hydroxychloroquine. Of the 55 patients, 22 died. The mean age of the patients who died was 42.8 years. Mortality rate was higher in individuals with DS over 40 years of age. CONCLUSION: More studies are needed to better understand COVID-19 infections among persons with DS. In addition, the study was limited by a lack of statistical analyses and a specific comparison group.

Outcomes of COVID-19 amongst patients with ongoing use of inhaled corticosteroids - a systematic review & meta-analysis.

Background: WHO quoted the numbers for the Coronavirus disease 2019 (COVID-19) pandemic as of August 2021 were 200 million cases with over 4 million deaths globally. COVID-19 is associated with several respiratory pathologies. Inhaled corticosteroids (ICS) are used to improve lung function by reducing inflammation, edema, mucus secretion, and inhibiting various cytokine activities. However, there is limited data on the effect of ICS usage in patients with COVID-19. In this study, we aim to evaluate the association between the use of ICS and the outcomes in COVID-19 patients compared to standard COVID-19 treatment. Methods: We followed PRISMA guidelines and MOOSE protocol for conducting the systematic review and meta-analysis comparing ICS and standard COVID-19 therapy. A search on PubMed is conducted yielding 270 articles of which 6 manuscripts are finalized for inclusion in the study. Patients with COVID-19 are identified from the studies based on confirmed positive RT-PCR tests. Hospitalization, ICU admission, and mortality are selected as the outcomes of our study. Using RevMan 5.3, we performed random-effects models to estimate the pooled effect size (pooled odds ratio), 95% confidence interval (95% CI), and heterogeneity (I2). Forest plots are obtained and p <0.05 is considered statistically significant. Results: Our study involves the comparison of ICS vs Non-ICS for mortality (N= 207,842 vs 166,217), ICU hospitalization (N= 1,084 vs 9,425), and the risk of hospitalization (N= 1,273 vs 1,676).Of the six studies, five reported mortality. We found a higher mortality rate in patients with asthma (60.88%, 107/160) and chronic obstructive pulmonary disease (COPD) (68.46%, 382/558) among ICS users. The overall mortality is 7.49% (107/1428). We found that ICS use was associated with higher odds of mortality (OR=1.45 95%CI: 1.10-1.91; p=0.009, I2= 68%) amongst COVID-19 patients. In subgroup analysis, higher odds of mortality among COPD patients using ICS was noted [pooled OR: 1.52 (1.24-1.86); p<0.0001; I2=0%]. However, no significant association between ICS and mortality was observed among asthma patients. Conclusion: ICS is associated with increased mortality and risk for hospitalization in patients with COVID-19 as compared to standard non-steroid-based COVID-19 therapy. It is crucial for healthcare providers to carefully evaluate the potential risks and benefits of ICS usage in the context of COVID-19 management to optimize patient outcomes and safety.

Effect of fibrinolytic therapy on ST-elevation myocardial infarction clinical outcomes during the COVID-19 pandemic: A systematic review and meta-analysis.

BACKGROUND: ST-elevation myocardial infarction (STEMI) is the result of transmural ischemia of the myocardium and is associated with a high mortality rate. Primary percutaneous coronary intervention (PPCI) is the recommended first-line treatment strategy for patients with STEMI. The timely delivery of PPCI became extremely challenging for STEMI patients during the coronavirus disease 2019 (COVID-19) pandemic, leading to a projected steep rise in mortality. These delays were overcome by the shift from first-line therapy and the development of modern fibrinolytic-based reperfusion. It is unclear whether fibrinolytic-based reperfusion therapy is effective in improving STEMI endpoints. AIM: To determine the incidence of fibrinolytic therapy during the COVID-19 pandemic and its effects on STEMI clinical outcomes. METHODS: PubMed, Google Scholar, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials were queried from January 2020 up to February 2022 to identify studies investigating the effect of fibrinolytic therapy on the prognostic outcome of STEMI patients during the pandemic. Primary outcomes were the incidence of fibrinolysis and the risk of all-cause mortality. Data were meta-analyzed using the random effects model to derive odds ratios (OR) and 95% confidence intervals. Quality assessment was carried out using the Newcastle-Ottawa scale. RESULTS: Fourteen studies including 50136 STEMI patients (n = 15142 in the pandemic arm; n = 34994 in the pre-pandemic arm) were included. The mean age was 61 years; 79% were male, 27% had type 2 diabetes, and 47% were smokers. Compared with the pre-pandemic period, there was a significantly increased overall incidence of fibrinolysis during the pandemic period [OR: 1.80 (1.18 to 2.75); I2= 78%; P = 0.00; GRADE: Very low]. The incidence of fibrinolysis was not associated with the risk of all-cause mortality in any setting. The countries with a low-and middle-income status reported a higher incidence of fibrinolysis [OR: 5.16 (2.18 to 12.22); I2 = 81%; P = 0.00; GRADE: Very low] and an increased risk of all-cause mortality in STEMI patients [OR: 1.16 (1.03 to 1.30); I2 = 0%; P = 0.01; GRADE: Very low]. Meta-regression analysis showed a positive correlation of hyperlipidemia (P = 0.001) and hypertension (P < 0.001) with all-cause mortality. CONCLUSION: There is an increased incidence of fibrinolysis during the pandemic period, but it has no effect on the risk of all-cause mortality. The low- and middle-income status has a significant impact on the all-cause mortality rate and the incidence of fibrinolysis.

A Rare Co-association of Autoimmune Thyroiditis and Idiopathic Retroperitoneal Fibrosis.

Retroperitoneal fibrosis is a rare fibroinflammatory disease that is reported to be associated with other autoimmune conditions. Here, we report the case of a 51-year-old Caucasian female with a history of autoimmune thyroiditis and Hashimoto's hypothyroidism who presented with symptoms of fever, chills, and hot flashes for three weeks associated with nausea, vomiting, frequent thirst, and frequent urination. On examination, the patient had elevated blood pressure and an excoriated rash on the forearms. Laboratory evaluation showed elevated blood urea nitrogen and creatinine with a hypertensive emergency. Renal ultrasound showed bilateral hydronephrosis suggestive of obstructive uropathy. Computerized tomography of the abdomen and pelvis was suggestive of extensive retroperitoneal fibrosis. The patient was diagnosed with idiopathic retroperitoneal fibrosis without an identifiable secondary cause. Treatment was focused on relieving the ureteral obstruction, managing renal functions, and optimizing blood pressure, following which immunomodulatory agents were used.

Apheresis: A cell-based therapeutic tool for the inflammatory bowel disease.

Inflammatory Bowel Disease (IBD) is a hallmark of leukocyte infiltration, followed by the release of cytokines and interleukins. Disease progression to Ulcerative Colitis (UC) or Crohn's Disease (CD) remained largely incurable. The genetic and environmental factors disrupt enteral bacteria in the gut, which hampers the intestinal repairing capability of damaged mucosa. Commonly practiced pharmacological therapies include 5-aminosalicylic acid with corticosteroids and tumor necrosis factor (TNF)-α. New interventions such as CDP571 and TNF-blocking RDP58 report the loss of patient response. This review discusses the non-pharmacologic selective granulocyte-monocyte-apheresis (GMA) and leukocytapheresis (LCAP) that have been proposed as treatment modalities that reduce mortality. GMA, an extracorporeal vein-to-vein technique, presents a strong safety profile case for its use as a viable therapeutic option compared to GMA's conventional medication safety profile. GMA reported minimal to no side effects in the pediatric population and pregnant women. Numerous studies report the efficacious nature of GMA in UC patients, whereas data on CD patients is insufficient. Its benefits outweigh the risks and are emerging as a favored non-pharmacological treatment option. On the contrary, LCAP uses a general extracorporeal treatment that entraps leukocytes and suppresses cytokine release. It has been deemed more efficacious than conventional drug treatments, the former causing better disease remission, and maintenance. Patients with UC/CD secondary to complications have responded well to the treatment. Side effects of the procedure have remained mild to moderate, and there is little evidence of any severe adverse event occurring in most age groups. LCAP decreases the dependence on steroids and immunosuppressive therapies for IBD. The review will discuss the role of GMA and LCAP.

Is There a Bias Toward Unvaccinated COVID-19 Patients?

Description With more than 22% of the United States still not vaccinated for COVID-19, we are trying to shed some light on whether there is any bias when treating unvaccinated COVID-19 patients. We highlight several reports where some individuals or organizations displayed possible bias, whether implicit or explicit. We examine the legal and ethical implications of these biases and offer a general overview of how to tackle them.

A review of adverse effects of COVID-19 vaccines.

The COVID-19 pandemic has led to unanticipated pressures on all aspects of human life. Multiple approaches to eliciting protective immunity must be rapidly evaluated. Numerous efforts have been made to develop an effective vaccine for this novel coronavirus, resulting in a race for vaccine development. To combat COVID-19, all nations must focus their efforts on widespread vaccination with an effective and safe vaccine. Globally, concerns about potential long-term adverse effects of vaccines have led to some apprehension about vaccine use. A vaccine's adverse effect has an integral role in the public's confidence and vaccine uptake. This article reviews the current primary literature regarding adverse effects associated with different COVID-19 vaccines in use worldwide.

Incidence, predictors, and outcomes of early hospital readmissions after kidney transplantation: Systemic review and meta-analysis.

Background: Early hospital readmission (EHR) within 30 days after kidney transplantation is a significant quality indicator of transplant centers and patient care. This meta-analysis aims to evaluate the incidence, predictors, and outcomes of EHR after kidney transplantation. Methods: We comprehensively searched the databases, including PubMed, Cochrane CENTRAL, and Embase, from inception until December 2021 to identify studies that assessed incidence, risk factors, and outcome of EHR. The outcomes included death-censored graft failure and mortality. Data from each study were combined using the random effect to calculate the pooled incidence, mean difference (MD), odds ratio (OR), and hazard ratio (HR) with 95% confidence interval (CI). Results: A total of 17 studies were included. The pooled EHR incidence after kidney transplant was 24.4% (95% CI 21.7-27.3). Meta-analysis showed that recipient characteristics, including older recipient age (MD 2.05; 95% CI 0.90-3.20), Black race (OR 1.31; 95% CI 1.11, 1.55), diabetes (OR 1.32; 95% CI 1.22-1.43), and longer dialysis duration (MD 0.85; 95% CI 0.41, 1.29), donor characteristics, including older donor age (MD 2.02; 95% CI 0.93-3.11), and transplant characteristics, including delayed graft function (OR 1.75; 95% CI 1.42-2.16) and longer length of hospital stay during transplantation (MD 1.93; 95% CI 0.59-3.27), were significantly associated with the increased risk of EHR. EHR was significantly associated with the increased risk of death-censored graft failure (HR 1.70; 95% CI 1.43-2.02) and mortality (HR 1.46; 95% CI 1.27-1.67) within the first year after transplantation. Conclusion: Almost one-fourth of kidney transplant recipients had EHR within 30 days after transplant, and they had worse post-transplant outcomes. Several risk factors for EHR were identified. This calls for future research to develop and implement for management strategies to reduce EHR in high-risk patients.

Electrical neuromodulation therapy for inflammatory bowel disease.

Inflammatory bowel disease (IBD) is an inflammatory disease of the gastrointestinal (GI) tract. It has financial and quality of life impact on patients. Although there has been a significant advancement in treatments, a considerable number of patients do not respond to it or have severe side effects. Therapeutic approaches such as electrical neuromodulation are being investigated to provide alternate options. Although bioelectric neuromodulation technology has evolved significantly in the last decade, sacral nerve stimulation (SNS) for fecal incontinence remains the only neuromodulation protocol commonly utilized use for GI disease. For IBD treatment, several electrical neuromodulation techniques have been studied, such as vagus NS, SNS, and tibial NS. Several animal and clinical experiments were conducted to study the effectiveness, with encouraging results. The precise underlying mechanisms of action for electrical neuromodulation are unclear, but this modality appears to be promising. Randomized control trials are required to investigate the efficacy of intrinsic processes. In this review, we will discuss the electrical modulation therapy for the IBD and the data pertaining to it.

Novel drug delivery systems for inflammatory bowel disease.

Inflammatory bowel disease (IBD) is a chronic illness characterized by relapsing inflammation of the intestines. The disorder is stratified according to the severity and is marked by its two main phenotypical representations: Ulcerative colitis and Crohn's disease. Pathogenesis of the disease is ambiguous and is expected to have interactivity between genetic disposition, environmental factors such as bacterial agents, and dysregulated immune response. Treatment for IBD aims to reduce symptom extent and severity and halt disease progression. The mainstay drugs have been 5-aminosalicylates (5-ASAs), corticosteroids, and immunosuppressive agents. Parenteral, oral and rectal routes are the conventional methods of drug delivery, and among all, oral administration is most widely adopted. However, problems of systematic drug reactions and low specificity in delivering drugs to the inflamed sites have emerged with these regular routes of delivery. Novel drug delivery systems have been introduced to overcome several therapeutic obstacles and for localized drug delivery to target tissues. Enteric-coated microneedle pills, various nano-drug delivery techniques, prodrug systems, lipid-based vesicular systems, hybrid drug delivery systems, and biologic drug delivery systems constitute some of these novel methods. Microneedles are painless, they dislodge their content at the affected site, and their release can be prolonged. Recombinant bacteria such as genetically engineered Lactococcus Lactis and eukaryotic cells, including GM immune cells and red blood cells as nanoparticle carriers, can be plausible delivery methods when evaluating biologic systems. Nano-particle drug delivery systems consisting of various techniques are also employed as nanoparticles can penetrate through inflamed regions and adhere to the thick mucus of the diseased site. Prodrug systems such as 5-ASAs formulations or their derivatives are effective in reducing colonic damage. Liposomes can be modified with both hydrophilic and lipophilic particles and act as lipid-based vesicular systems, while hybrid drug delivery systems containing an internal nanoparticle section for loading drugs are potential routes too. Leukosomes are also considered as possible carrier systems, and results from mouse models have revealed that they control anti- and pro-inflammatory molecules.

Electronic Cigarettes: Are They Smoking Cessation Aids or Health Hazards?

The US Food and Drug Administration (FDA) recently approved the marketing of an electronic cigarette (e-cig) brand called Vuse (RJ Reynolds Vapor Company, US) to help aid in smoking cessation for adult smokers. It was believed that the consumption of traditional cigarettes and their harmful effects would be reduced given the availability of newer e-cigarettes. However, adolescent use of tobacco and nicotine products rather increased with the availability of the same e-cigarettes, and the FDA-approved market boom only worsened this problem. Although the FDA underlines the importance of marketing e-cigarettes as a possible solution for adult traditional smoking, its consequences on adolescents' health raise many concerns, which we narrated in this review article.

COVID-19 Infection and Guillain-Barre Syndrome: A Case Series.

The coronavirus disease 2019 (COVID-19) pandemic brought about an unprecedented time. Multiple systemic complications have been recognized with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as it can do much more than affect the respiratory system. One of the intriguing neurological complications is Guillain-Barre syndrome (GBS). We reviewed three cases in which patients presented with GBS following COVID-19 infection. All three cases had positive lumbar puncture results with albumino-cytological dissociation. Each patient was treated with plasmapheresis and improved clinically. Although an exact causal relationship between COVID-19 and GBS cannot be drawn from this case series alone, it signifies the importance of this complication. It warrants further studies to establish the causal relationship. One should have a high suspicion for acute inflammatory demyelinating polyneuropathy (AIDP) in patients presenting with acute onset of ascending weakness following COVID-19 infection.

Vitamin D: The Missing Nutrient Behind the Two Deadly Pandemics, COVID-19 and Cardiovascular Diseases.

The coronavirus (COVID-19) pandemic is claiming millions of lives and creating an additional burden on health care, which is already affected by the rise of non-communicable diseases (NCDs). The scientific community, on the other side, is enormously engaged with studies to best identify the characteristics of the virus and minimize its effect while supporting the fight to contain NCDs, mainly cardiovascular diseases (CVDs), which are contributing hugely to the global death toll. Hence, the roles of vitamin D in COVID-19 immunity and cardiovascular health are gaining traction recently.  This literature review will mainly focus on summarizing pertinent studies and scientific publications which highlight the association of vitamin D levels with the various outcomes of COVID-19 and CVDs. It will also address how low vitamin D correlates with the epidemiology of CVDs and the inflammatory mechanisms attributed to COVID-19 severity. We believe that our review may open up hindsight perspectives and further discussions among the physicians in tapping the potential of vitamin D supplementation to tackle the morbidity, mortality, and health care cost of the two deadly diseases, COVID-19 and CVDs.

Idiopathic Systemic Capillary Leak Syndrome: A Rare Cause of Refractory Shock Following Influenza B Infection.

A 68-year-old man presented to the Emergency Department with undifferentiated shock. During the three days prior, he experienced a non-specific viral-like illness. On examination his blood pressure was 70/40 mm Hg with cool, clammy, and mottled extremities and flat neck veins. Laboratory investigations revealed a positive influenza B screen alongside elevated hemoglobin and hematocrit. Following aggressive fluid resuscitation his blood pressure had marginally improved and he was transferred to the intensive care unit (ICU). Vasopressor support with cautious fluid resuscitation continued and at 7- and 10-h following presentation, serum albumin levels were extremely low. Idiopathic systemic capillary leak syndrome triggered by influenza B infection was diagnosed. Following a 9-day ICU stay the patient made a complete recovery and remains stable on intravenous immunoglobulin therapy. This case highlights the importance judicious fluid resuscitation and serum albumin levels when confronted with refractory shock.

Diagnostic Accuracy of Elastography and Liver Disease: A Meta-Analysis.

Background: Ultrasound-based transient elastography (TE) is a non-invasive alternative to liver biopsy for the staging of hepatic fibrosis due to various chronic liver diseases. This meta-analysis aims to assess the diagnostic accuracy of TE for detecting liver cirrhosis (F4) and severe fibrosis (F3) in patients with chronic liver diseases, in comparison to the gold standard liver biopsy. Methods: A systematic search was performed using PubMed search engine following Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines from inception to May 2021. The meta-analysis studies evaluating the diagnostic accuracy of TE for severe fibrosis and cirrhosis were identified. We conducted a meta-meta-analysis to generate pooled estimates of the sensitivity, specificity, and diagnostic odds ratios (ORs) for F3 and F4 fibrosis stage. Results: We included five studies with a total of 124 sub-studies and 20,341 patients in our analysis. Three studies have reported the diagnostic accuracy of TE in detecting F3/severe fibrosis stage and found 81.9% pooled sensitivity (95% confidence interval (CI): 79.9-83.7%; P < 0.001) (I2 = 0%), 84.7% pooled specificity (95% CI: 81.3-87.6%) (I2 = 81%; P = 0.02). All five studies reported the diagnostic accuracy of TE in detecting F4/liver cirrhosis stage. We found 84.8% pooled sensitivity (95% CI: 81.4-87.7%) (I2 = 86.4%; P < 0.001), 87.5% pooled specificity (95% CI: 85.4-89.3%) (I2 = 90%; P < 0.001) and pooled diagnostic OR (41.8; 95% CI: 3.9 - 56.5) (I2 = 87%; P < 0.001). Conclusions: Ultrasound-based TE has excellent diagnostic accuracy for identifying cirrhosis and liver fibrosis stages 3. Future studies should focus on estimating the diagnostic accuracy of other fibrosis stages in chronic liver disease patients. This will eventually decrease the risk associated with invasive liver biopsy.

Differential mortality with COVID-19 and invasive mechanical ventilation between high-income and low-and middle-income countries: a systematic review, meta-analysis, and meta-regression.

The COVID-19 pandemic has markedly affected the health care of patients in low- and middle-income countries (LMICs), but no systematic study to corroborate this effect has been undertaken. In addition, the survival outcomes of patients with COVID-19 who received invasive mechanical ventilation (IMV) have not been well established. We pooled evidence from all available studies and did a systematic review and meta-analysis to assess and compare mortality outcomes between LMICs and high-income countries (HICs). We searched MEDLINE and the University of Michigan Library according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines from December 1, 2019, to July 15, 2021, for case-control studies, cohort studies, and brief reports that discussed mortality ratios and survival outcomes among patients with SARS-CoV-2 who received IMV. We excluded studies and case reports without comparison groups, narrative reviews, and preprints. A random-effects estimate of the arcsine square root transformation (PAS) of each outcome was generated with the DerSimonian-Laird method. Seven eligible studies, consisting of 243,835 patients with COVID-19, were included. We identified a significantly higher mortality rate (i.e., a larger PAS) among the patients receiving IMV in LMICs (PAS, 0.754; 95% CI, 0.569-0.900; P<.001) compared to patients in HICs (PAS, 0.588; 95% CI, 0.263-0.876; P<.001). Considerable heterogeneity was present within the individual subgroups possibly because of the extent of the included studies, which had data from specific countries and states but not from individual hospitals or health care centers. Moreover, the sample population in each study was diverse. Meta-regression showed that a higher mortality rate among patients with COVID-19 who received IMV in both HICs (P<.001) and LMICs (P=.04) was associated with chronic pulmonary disease. Our study suggests that chronic pulmonary diseases and poor demographics lead to a worse prognosis among patients with COVID-19 who received IMV. Moreover, the survival outcome is worse in LMICs, where health care systems are usually understaffed and poorly financed.