Equivalency of Protection from Natural Immunity in COVID-19 Recovered Versus Fully Vaccinated Persons: A Systematic Review and Pooled Analysis

BACKGROUND: We present a systematic review and pooled analysis of clinical studies to date, that (1) specifically compare the protection of natural immunity in the COVID-recovered versus the efficacy of full vaccination in the COVID-naive, and (2) the added benefit of vaccination in the COVID-recovered, for prevention of subsequent SARS-CoV-2 infection. METHODS: Using the PRISMA 2020 guidance, we first conducted a systematic review of available literature on PubMed, MedRxIV and FDA briefings to identify clinical studies either comparing COVID vaccination to natural immunity or delineating the benefit of vaccination in recovered individuals. After assessing for eligibility, studies were qualitatively appraised and formally graded using the NOS system for observational, case-control and RCTs. Incidence rates were tabulated for the following groups: never infected (NI) and unvaccinated (UV), NI and vaccinated (V), previously infected (PI) and UV, PI and UV. Pooling was performed by grouping the RCTs and observational studies separately, and then all studies in total. Risk ratios and risk differences are reported for individual studies and pooled groups, in 1) NPI/V vs. PI/UV and 2) PI/UV vs. PI/V analysis. In addition, number needed to treat (NNT) analysis was performed for vaccination in naive and previously infected cohorts. RESULTS: Nine clinical studies were identified including three randomized controlled studies, four retrospective observational cohorts, one prospective observational cohort, and a case-control study. The NOS quality appraisals of these articles ranged from four to nine (out of nine stars). All of the included studies found at least statistical equivalence between the protection of full vaccination and natural immunity; and, three studies found superiority of natural immunity. Four observational studies found a statistically significant incremental benefit to vaccination in the COVID-recovered individuals. In total pooled analysis, incidence in NPI/V trended higher than PI/UV groups (RR=1.86 [95%CI 0.77-4.51], P=0.17). Vaccination in COVID-recovered individuals provided modest protection from reinfection (RR=1.82 [95%CI 1.21-2.73], P=0.004), but the absolute risk difference was extremely small (AR= 0.004 person-years [95% CI 0.001-0.007], P=0.02). The NNT to prevent one annual case of infection in COVID-recovered patients was 218, compared to 6.5 in COVID-naive patients, representing a 33.5-fold difference in benefit between the two populations. CONCLUSIONS: While vaccinations are highly effective at protecting against infection and severe COVID-19 disease, our review demonstrates that natural immunity in COVID-recovered individuals is, at least, equivalent to the protection afforded by full vaccination of COVID-naive populations. There is a modest and incremental relative benefit to vaccination in COVID-recovered individuals; however, the net benefit is marginal on an absolute basis. COVID-recovered individuals represent a distinctly different benefit-risk calculus. Therefore, vaccination of COVID-recovered individuals should be subject to clinical equipoise and individual preference.

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Indomethacin Responsive Headaches: Exhaustive Systematic Review With Pooled Analysis and Critical Appraisal of 81 Published Clinical Studies

Headache The Journal of Head and Face Pain ◽

10.1111/head.12771 ◽

2016 ◽

Vol 56 (2) ◽

pp. 422-435 ◽

Cited By ~ 3

Author(s):

Emilia C. Bordini ◽

Carlos A. Bordini ◽

Yohannes W. Woldeamanuel ◽

Alan M. Rapoport

Keyword(s):

Systematic Review ◽

Clinical Studies ◽

Critical Appraisal ◽

Pooled Analysis

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Dietary Fibre Intake in Relation to Asthma, Rhinitis and Lung Function Impairment—A Systematic Review of Observational Studies

Nutrients ◽

10.3390/nu13103594 ◽

2021 ◽

Vol 13 (10) ◽

pp. 3594

Author(s):

Emmanouela Sdona ◽

Athina Vasiliki Georgakou ◽

Sandra Ekström ◽

Anna Bergström

Keyword(s):

Systematic Review ◽

Lung Function ◽

Dietary Fibre ◽

Observational Studies ◽

Case Control ◽

Cross Sectional ◽

Fibre Intake ◽

Function Impairment ◽

Dietary Fibre Intake ◽

Lung Function Impairment

A high intake of dietary fibre has been associated with a reduced risk of several chronic diseases. This study aimed to review the current evidence on dietary fibre in relation to asthma, rhinitis and lung function impairment. Electronic databases were searched in June 2021 for studies on the association between dietary fibre and asthma, rhinitis, chronic obstructive pulmonary disease (COPD) and lung function. Observational studies with cross-sectional, case–control or prospective designs were included. Studies on animals, case studies and intervention studies were excluded. The quality of the evidence from individual studies was evaluated using the RoB-NObs tool. The World Cancer Research Fund criteria were used to grade the strength of the evidence. Twenty studies were included in this systematic review, of which ten were cohort studies, eight cross-sectional and two case–control studies. Fibre intake during pregnancy or childhood was examined in three studies, while seventeen studies examined the intake during adulthood. There was probable evidence for an inverse association between dietary fibre and COPD and suggestive evidence for a positive association with lung function. However, the evidence regarding asthma and rhinitis was limited and inconsistent. Further research is needed on dietary fibre intake and asthma, rhinitis and lung function among adults and children.

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Intra-arterial vasodilators to prevent radial artery spasm: a systematic review and pooled analysis of clinical studies

Cardiovascular Revascularization Medicine ◽

10.1016/j.carrev.2015.08.008 ◽

2015 ◽

Vol 16 (8) ◽

pp. 484-490 ◽

Cited By ~ 38

Author(s):

Chun Shing Kwok ◽

Muhammad Rashid ◽

Doug Fraser ◽

James Nolan ◽

Mamas Mamas

Keyword(s):

Systematic Review ◽

Radial Artery ◽

Clinical Studies ◽

Pooled Analysis

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Effect of Exposure to Cats and Dogs on the Risk of Asthma and Allergic Rhinitis: A Systematic Review and Meta-analysis

American Journal of Rhinology and Allergy ◽

10.1177/1945892420932487 ◽

2020 ◽

Vol 34 (5) ◽

pp. 703-714

Author(s):

Xiaoping Gao ◽

Mei Yin ◽

Pei Yang ◽

Xia Li ◽

Lingling Di ◽

...

Keyword(s):

Systematic Review ◽

Allergic Rhinitis ◽

Cohort Studies ◽

Meta Analysis ◽

Pooled Analysis ◽

Protective Role ◽

Case Control ◽

Favorable Effect ◽

Case Control Studies

Background Controversies persist regarding whether exposure to cat or dog increases the risk of asthma and allergic rhinitis. Objective This meta-analysis aimed to assess the associations between exposure to cats or dogs and the development of asthma and allergic rhinitis. Methods A systematic review was performed to identify case-control and cohort studies before May 2019, evaluating the association between exposure to cats and dogs and the risk of asthma and rhinitis. The risk of bias was assessed using the Newcastle–Ottawa Scale. The odds ratios (ORs) and risk ratios (RRs) were pooled for case-control and cohort studies, respectively. Subgroup analyses were performed on prespecified study-level characteristics. Results The meta-analysis of 34 cohort studies showed a protective role of exposure to cats [RR: 0.88, 95% confidence interval (CI): 0.77–0.99] or dogs (RR: 0.85, 95% CI: 0.73–0.97) in the development of asthma. The subgroup analysis of birth cohort (RR: 0.74, 95% CI: 0.56–0.93) and children population (RR: 0.83, 95% CI: 0.70–0.96) also suggested a favorable role of exposure to dogs in the development of asthma. Pooled evidence from 13 case-control studies indicated no significant impact of cats (OR: 1.66, 95% CI: 0.39–2.94) and dogs (OR: 1.22, 95% CI: 0.92–1.52) on the development of asthma. A pooled analysis of five cohort studies showed a favorable effect of exposure to cats (RR: 0.60, 95% CI: 0.33–0.86) or dogs (RR: 0.68, 95% CI 0.44–0.90) on the development of allergic rhinitis. Conclusion The findings indicated a protective effect of exposure to cats and dogs, especially ownership, on the development of asthma and allergic rhinitis.

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Egg Consumption and Risk of Upper Aero-Digestive Tract Cancers: A Systematic Review and Meta-Analysis of Observational Studies

Advances in Nutrition ◽

10.1093/advances/nmz010 ◽

2019 ◽

Vol 10 (4) ◽

pp. 660-672 ◽

Cited By ~ 1

Author(s):

Azadeh Aminianfar ◽

Roohallah Fallah-Moshkani ◽

Asma Salari-Moghaddam ◽

Parvane Saneei ◽

Bagher Larijani ◽

...

Keyword(s):

Systematic Review ◽

Esophageal Cancer ◽

Cohort Studies ◽

Prospective Cohort ◽

Observational Studies ◽

Meta Analysis ◽

Case Control ◽

Egg Consumption ◽

Prospective Cohort Studies ◽

Increased Risk

ABSTRACT Limited data are available that summarize the relation between egg intake and the risk of upper aero-digestive tract (UADT) cancers. This systematic review and meta-analysis was conducted to investigate the association between egg intake and the risk of UADT cancers. Medline/PubMed, ISI web of knowledge, EMBASE, Scopus, and Google Scholar were searched using relevant keywords. Observational studies conducted on humans investigating the association between egg consumption and the risk of UADT cancers were included. Overall, 38 studies with a total of 164,241 subjects (27, 025 cases) were included. Based on 40 effect sizes from 32 case-control studies, we found a 42% increased risk of UADT cancers among those with the highest egg consumption (ranging from ≥1 meal/d to ≥1 time/mo among studies) compared to those with the lowest intake (ranging from 0–20 g/d to never consumed among studies) (overall OR: 1.42; 95% CI: 1.19, 1.68; P < 0.001). However, this association was only evident in hospital-based case-control (HCC) studies (OR = 1.50; 95% CI: 1.34, 1.68; P < 0.001 for ‘oropharyngeal and laryngeal cancer’ and OR: 1.27; 95% CI: 1.08, 1.50; P = 0.004 for esophageal cancer) and not in population-based case-control (PCC) studies (OR = 1.25; 95% CI: 0.59, 2.67; P = 0.56 for ‘oropharyngeal and laryngeal cancer’ and OR: 1.29; 95% CI: 0.92, 1.81; P = 0.13 for esophageal cancer). In addition, the association was not significant in prospective cohort studies (overall OR: 0.86; 95% CI: 0.71, 1.04; P = 0.11). Considering individual cancers, a positive association was observed between the highest egg consumption, compared with the lowest, and risk of oropharyngeal (OR: 1.88; 95% CI: 1.61, 2.20; P < 0.001), laryngeal (OR: 1.83; 95% CI: 1.45, 2.32; P < 0.001), oral & pharyngeal & laryngeal (OR: 1.37; 95% CI: 1.12, 1.67; P < 0.001), and esophageal cancers (OR: 1.28; 95% CI: 1.10,1.48; P = 0.001). We also found an inverse association between egg intake and the risk of oral cancer (OR: 0.78; 95% CI: 0.62, 0.99; P = 0.04). In conclusion, high egg consumption (ranging from ≥1 meal/d to ≥1 time/mo among studies) was associated with increased risk of UADT cancers only in HCC studies but not in PCC or prospective cohort studies. PROSPERO registration number: CRD42018102619.

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Acid-suppressive medications and risk of esophageal adenocarcinoma in patients with Barrett’s esophagus: A systematic review and meta-analysis.

Journal of Clinical Oncology ◽

10.1200/jco.2014.32.3_suppl.11 ◽

2014 ◽

Vol 32 (3_suppl) ◽

pp. 11-11

Author(s):

Preet Paul Singh ◽

Siddharth Singh ◽

Sushil Kumar Garg ◽

Prasad G. Iyer ◽

Hashem El-Serag

Keyword(s):

Systematic Review ◽

Cohort Studies ◽

Barrett’S Esophagus ◽

Esophageal Adenocarcinoma ◽

Barrett's Esophagus ◽

Observational Studies ◽

Meta Analysis ◽

Number Needed To Treat ◽

Case Control Studies ◽

Inconsistency Index

11 Background: Acid-suppressive medications, particularly proton pump inhibitors (PPI), may modify risk of esophageal adenocarcinoma (EAC) in patients with Barrett’s esophagus (BE). We performed a systematic review and meta-analysis of studies evaluating the association between PPIs and histamine receptor antagonists (H2RA) and risk of EAC or high-grade dysplasia (BE-HGD) in patients with BE. Methods: Through a systematic search up to June 2013, we identified 7 observational studies (5 cohort studies and 2 case-control studies; 2,813 patients with BE, 317 cases of EAC and/or BE-HGD, 84.4% PPI users) reporting the association between PPIs or H2RA and EAC in patients with BE. Summary odds ratio (OR) with 95% confidence intervals (CI) was estimated using random effects model, and heterogeneity was measured using the inconsistency index (I2). Results: On meta-analysis, PPI use was associated with 71% reduction in EAC risk in patients with BE (adjusted OR, 0.29; 95% CI, 0.12-0.71). There was a trend toward a dose-response relationship with PPI use for >2 years protective against EAC [3 studies; PPI use >2 years vs. <2 years (as compared to no use): OR, 0.45 (0.19-1.06) vs. 1.09 (0.47-2.56)]. Considerable heterogeneity was observed in the overall analysis (I2=81%). On restricting analysis to 5 cohort studies, use of PPIs was consistently associated with a lower risk of EAC and/or BE-HGD (adjusted OR, 0.33; 95% CI, 0.19-0.58; I2=9%). H2RA use was not associated with decreased risk of EAC in patients with BE based on 2 studies (adjusted OR, 1.15; 95% CI, 0.77-1.72). Using a 67% summary risk reduction (derived from cohort studies) of EAC and/or BE-HGD with PPI use in patients with BE, and observed cumulative incidence rates of EAC and/or BE-HGD in patients with BE overall as 10.2 per 1,000 patient years, we estimate the number needed to treat with PPIs to prevent 1 case of EAC or BE-HGD in BE patients at 147. Conclusions: Based on meta-analysis of observational studies, the use of PPI, but not H2RA appears to be associated with a decreased risk of EAC and/or BE-HGD in patients with BE. PPI use should be considered in BE, and chemopreventive trials of PPIs in patients with BE are warranted.

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Association between green tea intake and risk of gastric cancer: a systematic review and dose–response meta-analysis of observational studies

Public Health Nutrition ◽

10.1017/s1368980017002208 ◽

2017 ◽

Vol 20 (17) ◽

pp. 3183-3192 ◽

Cited By ~ 15

Author(s):

Yanhong Huang ◽

Hongru Chen ◽

Liang Zhou ◽

Gaoming Li ◽

Dali Yi ◽

...

Keyword(s):

Gastric Cancer ◽

Systematic Review ◽

High Temperature ◽

Relative Risk ◽

Green Tea ◽

Dose Response ◽

Observational Studies ◽

Meta Analysis ◽

Case Control ◽

Case Control Studies

AbstractObjectiveTo examine and quantify the potential dose–response relationship between green tea intake and the risk of gastric cancer.DesignWe searched PubMed, EMBASE, Web of Science, CBM, CNKI and VIP up to December 2015 without language restrictions.SettingA systematic review and dose–response meta-analysis of observational studies.SubjectsFive cohort studies and eight case–control studies.ResultsCompared with the lowest level of green tea intake, the pooled relative risk (95 % CI) of gastric cancer was 1·05 (0·90, 1·21, I2=20·3 %) for the cohort studies and the pooled OR (95 % CI) was 0·84 (0·74, 0·95, I2=48·3 %) for the case–control studies. The pooled relative risk of gastric cancer was 0·79 (0·63, 0·97, I2=63·8 %) for intake of 6 cups green tea/d, 0·59 (0·42, 0·82, I2=1·0 %) for 25 years of green tea intake and 7·60 (1·67, 34·60, I2=86·5 %) for drinking very hot green tea.ConclusionsDrinking green tea has a certain preventive effect on reducing the risk of gastric cancer, particularly for long-term and high-dose consumption. Drinking too high-temperature green tea may increase the risk of gastric cancer, but it is still unclear whether high-temperature green tea is a risk factor for gastric cancer. Further studies should be performed to obtain more detailed results, including other gastric cancer risk factors such as smoking and alcohol consumption and the dose of the effective components in green tea, to provide more reliable evidence-based medical references for the relationship between green tea and gastric cancer.

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The efficacy of transcranial magnetic stimulation (TMS) for negative symptoms in schizophrenia: A systematic review and meta-analysis

10.1101/2021.11.05.21265787 ◽

2021 ◽

Author(s):

Rasmus Lorentzen ◽

Tuan Dang Nguyen ◽

Alexander McGirr ◽

Fredrik Hieronymus ◽

Soren Dinesen Ostergaard

Keyword(s):

Systematic Review ◽

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Negative Symptoms ◽

Meta Analysis ◽

Preliminary Evidence ◽

Pooled Analysis ◽

P Value ◽

Number Needed To Treat ◽

Double Blind

Several trials have shown preliminary evidence for efficacy using Transcranial Magnetic Stimulation (TMS) as a treatment for negative symptoms in schizophrenia. Here, we synthesize this literature using a systematic review and quantitative meta-analysis of double-blind randomized controlled trials of TMS in patients with schizophrenia. Specifically, MEDLINE, EMBASE, Web of Science, and PsycINFO were searched for sham-controlled, randomized trials of TMS among patients with schizophrenia. The standardized mean difference (SMD, Cohen's d) with 95% confidence intervals (CI) was calculated for each study (TMS vs. sham) and pooled across studies using an inverse variance random effects model. We identified 56 studies with a total of 2550 participants that were included in the meta-analysis. The pooled analysis showed statistically significant superiority of TMS (SMD=0.37, 95%CI: 0.23; 0.52, p-value <0.00001), corresponding to a number needed to treat of 4.85. Furthermore, stratified analyses suggested that TMS targeting the left dorsolateral prefrontal cortex, using a stimulation frequency >1 Hz, and a stimulation intensity at or above the motor threshold, was most efficacious. There was, however, substantial heterogeneity and high risk of bias among the included studies. In conclusion, TMS appears to be an efficacious treatment option for patients with schizophrenia suffering from negative symptoms, but the optimal TMS parameters have yet to be resolved.

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Relationship between caffeine intake and infertility: a systematic review of controlled clinical studies

10.21203/rs.3.rs-24250/v2 ◽

2020 ◽

Author(s):

Bu Fanlong ◽

Xue Feng ◽

Xiao-Ying Yang ◽

Jun Ren ◽

Hui-juan Cao

Keyword(s):

Systematic Review ◽

Cohort Study ◽

Clinical Studies ◽

Meta Analysis ◽

Case Control ◽

Average Score ◽

Caffeine Intake ◽

High Dose ◽

Case Control Studies ◽

High Doses

Abstract Background: Previous studies showed that high dose of caffeine intake may induce some specific human reproductive system diseases, even lead to infertility. This review is aimed to systematically review the evidence from all controlled clinical studies of caffeine intake for infertility.Methods: Relevant randomized/quasi-randomized controlled trials, non-randomized clinical studies, cohort studies, and case-control studies were included. Participants were either those without a history of infertility who are willing to have a baby (for prospective studies) or infertile patients with confirmed diagnosis (for retrospective studies). Caffeine or caffeine-containing beverage was observed as the exposure factor. The key outcome was the diagnosis of infertility.Results: Four studies (one cohort study and three case-control studies) involving 12912 participants were included. According Newcastle - Ottawa Scale (NOS), the average score of case-control studies was 6, and the cohort study achieved 9. Meta-analysis and subgroup analysis were conducted. The results showed that low (OR 0.95, 95%CI 0.78-1.16), medium (OR 1.14, 95%CI 0.69-1.86) and high doses (OR 1.86, 95%CI 0.28-12.22) of caffeine intake may not increase the risk of infertility. The GRADE method was used to assess the certainty of the evidence and the results showed that the quality of the three evidence bodies were all low.Conclusion: Our study provides low quality evidence that regardless of low, medium and high doses of caffeine intake do not appear increase the risk of infertility. But the conclusion should be treated with caution. Systematic review registration: PROSPERO CRD42015015714

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