COVID-19 and Parkinson's disease: a systematic review and meta-analysis.

This meta-analysis aimed to determine the prevalence, symptoms, and outcomes of COVID-19 in the elderly with Parkinson's disease (PD) by searching in the international databases of PubMed, Scopus, Web of Sciences, and EMBASE using the keywords of "COVID-19" and "Parkinson's." All articles related to Parkinson's disease and COVID-19 from January 2019 to October 20, 2021 were reviewed. The STATA software was used for analysis. A total of 20 articles were selected for data extraction in this meta-analysis, of which ten were cross-sectional studies (to determine the prevalence), five case-control studies, and five cohort studies (to examine the association). The results of the meta-analysis showed the prevalence of COVID-19 in patients with PD was 1.06% (95% CI 1.03-1.1%; P = 0.02), and the prevalence of their hospitalization due to COVID-19 was 0.98% (95% CI: 0.95-1.02%; P = 0.00). Also, the prevalence of depression and anxiety during the pandemic in this group was 46% (95% CI 29-64%; P = 0.00) and 43% (95% CI: 24-63%; P = 0.00), respectively. The prevalence of tremor and sleep problems were higher than those of other symptoms in the studied population. According to the results, there was no significant difference in the risk of COVID-19 infection between Parkinson's patients and healthy people. In other words, the risk of COVID-19 infection was equal in both groups (RR = 1.00 (CI 95% 0.77-1.30%; P = 0.15)). The results showed mortality and hospitalization rates of the elderly with Parkinson's disease were not significantly different from those of the general population during the COVID-19 pandemic. Also, the symptoms of Parkinson's disease and mental disorders increased during the COVID-19 pandemic. So, designing and developing more specific studies, like cohort studies, with large sample size is required for assessing these associations.

The association of chronic liver disorders with exacerbation of symptoms and complications related to COVID-19: A systematic review and meta-analysis of cohort studies.

INTRODUCTION: The aim of this review was to combine the results of published cohort studies to determine the exact association between chronic liver disorders, and the severe form of COVID-19, and its associated complications. METHODS: This meta-analysis employed a keyword search (COVID-19 and chronic liver disorders) using PubMed (Medline), Scopus, Web of Sciences, and Embase (Elsevier). All articles related from January 2019 to May 2022 were reviewed. The STATA software was used for analysis. RESULTS: The risk of death in COVID-19 patients with chronic liver disorders was higher than in ones without the chronic liver disease (RR: 1.52; CI 95%: 1.46-1.57; I2 : 86.14%). Also, the risk of acute respiratory distress syndrome (ARDS) and hospitalization in COVID-19 patients with chronic liver disorders was higher than in ones without the chronic liver disease ([RR: 1.65; CI 95%: 1.09-2.50; I2 : 0.00%] and [RR: 1.39; CI 95%: 1.23-1.58; I2 : 0.20%]). Also, the meta-analysis showed cough, headache, myalgia, nausea, diarrhea, and fatigue were 1.37 (CI 95%: 1.20-1.55), 1.23 (CI 95%: 1.09-1.38), 1.25 (CI 95%: 1.04-1.50), 1.19 (CI 95%: 1.02-1.40), 1.89 (CI 95%: 1.30-2.75), 1.49 (CI 95%: 1.07-2.09), and 1.14 (CI 95%: 0.98-1.33), respectively, whereas the risk of all these symptoms was higher in COVID-19 patients with chronic liver diseases than ones without chronic liver disorders. CONCLUSION: The mortality and complications due to COVID-19 were significantly different between patients with the chronic liver disease and the general population.

The effect of COVID-19 mRNA vaccines against postvaccination laboratory-confirmed SARS-CoV-2 infection, symptomatic COVID-19 infection, hospitalization, and mortality rate: a systematic review and meta-analysis.

OBJECTIVES: We systematically reviewed the literature to investigate the pooled effect of COVID-19 mRNA vaccination against SARS-CoV-2 infection and its clinical outcomes. METHODS: Scopus, Web of Science, PubMed (Medline), and Embase were searched on 9 September 2021. The odds ratio (OR) of COVID-19 infection and its clinical outcomes in fully/ partially vaccinated versus unvaccinated participants were calculated and pooled by using a random-effects model. RESULTS: The pooled analysis showed that among health care workers and general population, vaccinated participants with one or two doses were less likely to infect with SARS-CoV-2 (OR = 0.16; 95%CI: 0.08-0.32; I2 = 79.86%; 95%CI I2: 68.99-87.21%), to develop symptomatic COVID-19 infection (OR = 0.09; 95%CI: 0.03-0.32; I2 = 80.43%; 95%CI I2: 70.83-89.33%), to admit to the hospital because of COVID-19 (OR = 0.13; 95%CI: 0.06-0.28; I2 = 86.19%; 95%CI I2: 67.80-93.88%), and to die from COVID-19 (OR = 0.14; 95%CI: 0.06-0.35; I2 = 66.76%; 95%CI I2: 54.00-76.99%) than unvaccinated participants. CONCLUSIONS: COVID-19 mRNA vaccines, especially following administration of two doses, are extremely effective. It would be suggested further studies with large sample size and different ethnicities to be conducted among the general population to warrant these results.

SARS-CoV-2 seroprevalence around the world: an updated systematic review and meta-analysis.

BACKGROUND: Covid-19 has been one of the major concerns around the world in the last 2 years. One of the challenges of this disease has been to determine its prevalence. Conflicting results of the serology test in Covid explored the need for an updated meta-analysis on this issue. Thus, this systematic review aimed to estimate the prevalence of global SARS-CoV-2 serology in different populations and geographical areas. METHODS: To identify studies evaluating the seroprevalence of SARS-CoV-2, a comprehensive literature search was performed from international databases, including Medline (PubMed), Web of Sciences, Scopus, EMBASE, and CINHAL. RESULTS: In this meta-analysis, the results showed that SARS-CoV-2 seroprevalence is between 3 and 15% worldwide. In Eastern Mediterranean, the pooled estimate of seroprevalence SARS-CoV-2 was 15% (CI 95% 5-29%), and in Africa, the pooled estimate was 6% (CI 95% 1-13%). In America, the pooled estimate was 8% (CI 95% 6-11%), and in Europe, the pooled estimate was 5% (CI 95% 4-6%). Also the last region, Western Pacific, the pooled estimate was 3% (CI 95% 2-4%). Besides, we analyzed three of these areas separately. This analysis estimated the prevalence in subgroups such as study population, diagnostic methods, sampling methods, time, perspective, and type of the study. CONCLUSION: The present meta-analysis showed that the seroprevalence of SARS-CoV-2 has been between 3 and 15% worldwide. Even considering the low estimate of this rate and the increasing vaccination in the world, many people are still susceptible to SARS-CoV-2.