Potential Sources Of Heterogeneity Research Articles

Assessing the cost-effectiveness of precision medicine: protocol for a systematic review and meta-analysis

IntroductionPrecision medicine (PM) involves gene testing to identify disease risk, enable early diagnosis or guide therapeutic choice, and targeted gene therapy. We aim to perform a systematic review and meta-analysis...

Influence of Combination Antiretroviral Therapy on HIV-1 Serological Responses and Their Implications: A Systematic Review and Meta-Analysis.

We aimed to analyze HIV-1 seroreversion caused by combination antiretroviral therapy (cART) and to explore antibody levels of anti-HIV-1 as an alternative biomarker of HIV-1 reservoir. We searched PubMed, Embase, the Cochrane Library, and Web of Science up to August 2021 for publications about the performance of HIV-1 serological assays or the association between antibody responses against HIV-1 and HIV-1 reservoirs. Potential sources of heterogeneity were explored by meta-regression analysis, including the year of publication, country, pretreatment viral load, sample size, the timing of treatment, time on cART, and principle or type of serological assay. Twenty-eight eligible studies with a total population of 1,883 were included in the meta-analysis. The pooled frequency of HIV-1 seronegativity is 38.0% (95% CI: 28.0%–49.0%) among children with vertical HIV-1 infection and cART initiation at the age of less than 6 months, while the percentage of HIV-1 seronegativity declined to 1.0% (95% CI: 0%–3.0%) when cART was initiated at the age of >6 months. For adult patients, 16.0% (95% CI: 9.0%–24.0%) of them were serologically negative when cART was initiated at acute/early infection of HIV-1, but the seronegative reaction was rarely detected when cART was started at chronic HIV-1 infection. Substantial heterogeneity was observed among the studies to estimate the frequency of HIV-1 seronegativity in the early-cART population (I 2 ≥ 70%, p < 0.05 and all), while mild heterogeneity existed for the deferred-cART subjects. Moreover, anti-HIV-1 antibody response positively correlates with HIV-1 reservoir size with a pooled rho of 0.43 (95% CI: 0.28–0.55), suggesting that anti-HIV antibody level may be a feasible biomarker of HIV-1 reservoir size.

Symptom- and chest-radiography screening for active pulmonary tuberculosis in HIV-negative adults and adults with unknown HIV status.

Symptom- and chest-radiography screening for active pulmonary tuberculosis in HIV-negative adults and adults with unknown HIV status.

Predictive value of preoperative handgrip strength on postoperative outcomes in patients with gastrointestinal tumors: a systematic review and meta-analysis.

This systematic review and meta-analysis aimed to explore the predictive value of preoperative handgrip strength on postoperative outcomes in patients with gastrointestinal tumors. Databases including Cochrane Library, Pubmed, Embase, Web of Science, and CINAHL Complete were searched for articles published from the establishment of database until August 7, 2021. Two researchers independently screened the literature, extracted the data, and evaluated the quality. Eight studies were included, involving five prospective and three retrospective cohort studies with 2291 participants. The prevalence of preoperative low handgrip strength ranged from 11.8 to 62.7%. Preoperative low handgrip strength was associated with an increased risk of total complications (OR = 2.23, 95%CI = 1.43-3.50), pneumonia (OR = 5.16, 95%CI = 3.17-8.38), ileus (OR = 2.48, 95%CI = 1.09-5.65), and short-term mortality (OR = 7.28, 95%CI = 1.90-27.92). This systematic review and meta-analysis indicated that preoperative HGS had important value to predict certain adverse postoperative outcomes among patients with GI tumors. Low handgrip strength criteria, definition of total complications, and country are the potential sources of heterogeneity, and more research are required to test and update these results.

An Operations Approach for Reducing Glycemic Variability: Evidence from a Primary Care Setting

Problem definition: Diabetes is a highly prevalent and expensive chronic disease that affects millions of Americans and is associated with multiple comorbidities. Clinical research has found long-term variation in a patient’s glycated hemoglobin levels to be linked with adverse health outcomes, such as increased hospitalizations. Consequently, there is a need for innovative approaches to reduce long-term glycemic variability and efficient ways to implement them. Academic/practical relevance: Although the operations literature has extensively explored ways to manage variability across patients, relatively little attention has been paid to within-patient variability. We draw on the management and healthcare literatures to hypothesize and then show that a key operational lever—continuity of care (CoC)—can be used to reduce glycemic variability, which in turn, improves patient health. In the process, we explore the moderating role of a key demographic characteristic: patient’s marital status. We also shed light on an important mechanism through which CoC reduces variability—adherence of patients to prescribed medications—thereby advancing the compliance literature. Academically, our study adds to the understanding of the importance of managing variability (via continuity in service) in settings where customers repeatedly interact with service providers. Methodology: We use a detailed and comprehensive data set from the Veterans Health Administration, the largest integrated healthcare delivery system in the United States. This permits us to control for potential sources of heterogeneity. We analyze more than 300,000 patients—over an 11-year period—with diabetes, a chronic disease whose successful management requires managing glycemic variability. We use an empirical approach to, first, quantify the relationship between CoC and glycemic variability and second, show how this relationship differs based on patient’s marital status. Third, we estimate the mediation effect of patients’ adherence to medications. Finally, we quantify how glycemic variability mediates the relationship between CoC and three important outcomes. Our findings are validated by extensive robustness checks and sensitivity analyses. Results: We find that CoC is related to reductions in glycemic variability, more so for patients who are not married. However, this reduction is not linear in continuity; we find evidence of curvilinearity but with a sufficiently high stationary point so that benefits almost always accrue, albeit at a diminishing rate. Additionally, we find that one mechanism through which CoC may reduce variability is through patients’ adherence to medications. We also find evidence of partial mediation for glycemic variability in the CoC outcomes process chain. Our counterfactual analysis reveals the extent of improvement that enhanced continuity can bring, depending on where it is targeted. Managerial implications: Identifying the process measures through which continuity of care reduces variability is of interest to practitioners and policy makers as it can help design appropriate policies and pathways in terms of both processes and staffing/work allocation.

The effect of physical exercise on circulating brain-derived neurotrophic factor in healthy subjects: A meta-analysis of randomized controlled trials.

ObjectiveTo investigate how physical exercise (PE) would affect brain‐derived neurotrophic factor (BDNF) in randomized controlled trials (RCTs) of healthy subjects.MethodsSeven databases (PubMed, Web of Science, Cochrane, Embase, PsycINFO, CINAHL, SPORTDiscus) were searched for RCTs assessing the effects of PE on serum and/or plasma BDNF until December 18, 2021. Meta‐analysis was performed by random‐effects method with standardized mean difference (SMD) and 95% confidence intervals (CIs). Subgroup analysis and meta‐regression analysis were conducted to investigate the potential source of heterogeneity. Trim and fill method, and leave‐one‐out cross‐validation were conducted.ResultsEventually, 21 articles, involving 809 participants, were included in the meta‐analysis. Overall, both acute (5 trials, SMD: 1.20, 95% CI: 0.36 to 2.04, p = .005) and long‐term (17 trials, SMD: 0.68, 95% CI: 0.27 to 1.08, p = .001) PE had significant positive effects on BDNF levels. Via subgroup analysis, studies of long‐term PE with larger sample sizes, female participants, participants older than 60 years, and aerobic exercise contributed to a more pronounced improvement on BDNF levels than that found when all studies were combined.ConclusionBoth acute and long‐term PE had significant positive effects on circulating BDNF in healthy subjects. This review suggests that acute exercise and long‐term aerobic exercise are powerful forms of PE to enhance neurotrophic effect, especially for female subjects or subjects over 60 years.

Diagnostic accuracy of the visceral adiposity index in patients with metabolic-associated fatty liver disease: a meta-analysis

BackgroundConflicting results on the prognostic value of the visceral adiposity index (VAI) in patients with metabolic-associated fatty liver disease (MAFLD) have been reported. This study aimed to assess the diagnostic value of the VAI in MAFLD patients.MethodsThe Cochrane Library, PubMed, Embase, and other databases were searched to collect all documents that met the inclusion criteria from the establishment of the database to September 2021. The methodological quality of the included studies was assessed using the Newcastle–Ottawa Scale. The heterogeneity among the studies was analysed by the Cochran Q test and I2 test, and the appropriate model was selected according to the heterogeneity results. The diagnostic efficacy of the VAI was evaluated by sensitivity, specificity, and area under the curve, and a Fagan diagram was generated to evaluate the diagnostic ability of the VAI.ResultsA total of 9 studies were included. The overall quality of the included studies was good. Meta-analysis showed that the combined sensitivity of the VAI for the diagnosis of MAFLD was 0.70 [95% CI (0.69–0.71)], the combined specificity was 0.67 [95% CI (0.67–0.68)], the combined positive likelihood ratio was 2.08 [95% CI (1.87–2.31)], the combined negative likelihood ratio was 0.39 [95% CI (0.34–0.44)], and the combined diagnostic odds ratio was 5.81 [95% CI (4.73–7.14)]. The corresponding area under the curve was 0.79 [95% CI (0.75–0.82)]. Meta-regression analysis showed that the diagnostic method was a potential source of heterogeneity (P < 0.05). The Fagan diagram showed that the precision of MAFLD diagnosis was 70% when the pretest probability was set to 50% and then supplemented by the VAI.ConclusionsThe VAI is an independent predictor in the diagnosis of MAFLD and may be helpful in the detection of MAFLD. A VAI > 2.33 suggests that patients have a high probability of having MAFLD.

Is clindamycin effective in preventing infectious complications after oral surgery? Systematic review and meta-analysis of randomized controlled trials

ObjectiveTo determine the effect of clindamycin in the prevention of infection after oral surgery.Material and MethodsThis systematic review and meta-analysis followed the PRISMA statement, the PICO-framework and included only randomized controlled clinical trials. In all studies clindamycin was administered to prevent infections in patients who underwent oral surgery. Two independent researchers conducted the search, data extraction and risk of bias assessment. Included studies were classified by the type of oral surgery. Besides, data of patients, procedures and outcome variables were collected. Risk ratios (RR) and 95% confidence intervals (CI) were calculated by using Mantel–Haenszel model and the number needed to treat (NNT). Finally, any potential sources of heterogeneity were estimated.ResultsSeven trials of 540 articles met the inclusion criteria and were included in the qualitative synthesis. Four articles assessing the effect of oral clindamycin in third molar surgery were quantitatively analyzed. The overall RR was 0.66 (95% CI = 0.38–1.16), being non-statistically significant (p = 0.15). There was no heterogeneity between the studies I2 = 0, p = 0.44. The NNT was 29 (95% CI = 12- -57).ConclusionsThe effectiveness of clindamycin could not be evaluated except in third molar extraction. Oral clindamycin is ineffective in preventing infection in third molar surgery.Clinical RelevanceThere is a lack of high-quality evidence supporting the prescription of clindamycin to prevent infections after oral surgery, despite being frequently prescribed as an alternative for penicillin-allergic patients. Oral clindamycin has not been shown to be effective after third molar extractions.

Efficacy of N-acetylcysteine on idiopathic or postinfective non-cystic fibrosis bronchiectasis: a systematic review and meta-analysis protocol

IntroductionNon-cystic fibrosis (non-CF) bronchiectasis is a chronic pulmonary disorder that causes destruction and permanent dilatation of the airways, resulting in excessive sputum production, repeated infection and inflammation. A need for...

Effectiveness of COVID-19 Vaccines against Delta Variant (B.1.617.2): A Meta-Analysis.

Objectives: The highly transmissible COVID-19 Delta variant (DV) has contributed to a surge in cases and exacerbated the worldwide public health crisis. Several COVID-19 vaccines play a significant role in a high degree of protection against the DV. The primary purpose of this meta-analysis is to estimate the pooled effectiveness of the COVID-19 vaccines against the DV in terms of risk ratio (RR) among fully vaccinated, compared to unvaccinated populations. Methods: We carried out a systematic review, with meta-analysis of original studies focused on COVID-19 vaccines effectiveness against a DV clinical perspective among fully COVID-19 vaccinated populations, compared to placebo (unvaccinated populations), published between 1 May 2021 and 30 September 2021. Eleven studies containing the data of 17.2 million participants were identified and included in our study. Pooled estimates of COVID-19 vaccines effectiveness (i.e., risk ratio, RR) against the DV with 95% confidence intervals were assessed using random-effect models. Publication bias was assessed using Egger’s regression test and funnel plot to investigate potential sources of heterogeneity and identify any differences in study design. Results: A total population of 17.2 million (17,200,341 people) were screened for the COVID-19 vaccines’ effectiveness against the DV. We found that 61.13% of the study population were fully vaccinated with two doses of COVID-19 vaccines. The weighted pooled incidence of COVID-19 infection was more than double (20.07%) among the unvaccinated population, compared to the fully vaccinated population (8.16%). Overall, the effectiveness of the COVID-19 vaccine against the DV was 85% (RR = 0.15, 95% CI: 0.07–0.31). The effectiveness of COVID-19 vaccines varied slidably by study designs, 87% (RR = 0.13, 95% CI: 0.06–0.30) and 84% (RR = 0.16, 95% CI: 0.02, 1.64) for cohort and case-control studies, respectively. Conclusions: The effectiveness of COVID-19 vaccines were noted to offer higher protection against the DV among populations who received two vaccine doses compared with the unvaccinated population. This finding would help efforts to maximise vaccine coverage (i.e., at least 60% to 70% of the population), with two doses among vulnerable populations, in order to have herd immunity to break the chain of transmission and gain greater overall population protection more rapidly.

Trans Fatty Acid Biomarkers and Incident Type 2 Diabetes: Pooled Analysis of 12 Prospective Cohort Studies in the Fatty Acids and Outcomes Research Consortium (FORCE).

Trans fatty acids (TFAs) have harmful biologic effects that could increase the risk of type 2 diabetes (T2D), but evidence remains uncertain. We aimed to investigate the prospective associations of TFA biomarkers and T2D by conducting an individual participant-level pooled analysis. We included data from an international consortium of 12 prospective cohorts and nested case-control studies from six nations. TFA biomarkers were measured in blood collected between 1990 and 2008 from 25,126 participants aged ≥18 years without prevalent diabetes. Each cohort conducted de novo harmonized analyses using a prespecified protocol, and findings were pooled using inverse-variance weighted meta-analysis. Heterogeneity was explored by prespecified between-study and within-study characteristics. During a mean follow-up of 13.5 years, 2,843 cases of incident T2D were identified. In multivariable-adjusted pooled analyses, no significant associations with T2D were identified for trans/trans-18:2, relative risk (RR) 1.09 (95% CI 0.94-1.25); cis/trans-18:2, 0.89 (0.73-1.07); and trans/cis-18:2, 0.87 (0.73-1.03). Trans-16:1n-9, total trans-18:1, and total trans-18:2 were inversely associated with T2D (RR 0.81 [95% CI 0.67-0.99], 0.86 [0.75-0.99], and 0.84 [0.74-0.96], respectively). Findings were not significantly different according to prespecified sources of potential heterogeneity (each P ≥ 0.1). Circulating individual trans-18:2 TFA biomarkers were not associated with risk of T2D, while trans-16:1n-9, total trans-18:1, and total trans-18:2 were inversely associated. Findings may reflect the influence of mixed TFA sources (industrial vs. natural ruminant), a general decline in TFA exposure due to policy changes during this period, or the relatively limited range of TFA levels.

Antimicrobial-associated organ injury among the elderly: a systematic review and meta-analysis protocol

IntroductionOlder adults (aged 65 years and above) constitute the fastest growing population cohort in the western world. There is increasing evidence that the burden of infections disproportionately affects this cohort...

Prevalence of type-2 diabetes and prediabetes in Malaysia: A systematic review and meta-analysis.

The main purpose of this study was to investigate the pooled prevalence of prediabetes and type-2 diabetes in the general population of Malaysia. We systematically searched Medline (PubMed), Embase, Web of Science, Google Scholar and Malaysian Journals Online to identify relevant studies published between January 1, 1995, and November 30, 2021, on the prevalence of type-2 diabetes in Malaysia. Random-effects meta-analyses were used to obtain the pooled prevalence of diabetes and prediabetes. Subgroup analyses also used to analyze to the potential sources of heterogeneity. Meta- regression was carried to assess associations between study characteristics and diabetes prevalence. Three independent authors selected studies and conducted the quality assessment. The quality of the final evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Of 2689 potentially relevant studies, 786 titles and abstract were screened. Fifteen studies with 103063 individuals were eligible to be included in the meta-analyses. The pooled prevalence of diabetes was 14.39% (95% CI, 12.51%-16.38%; I2 = 98.4%, 103063 participants from 15 studies). The pooled prevalence of prediabetes was 11.62% (95% CI, 7.17%-16.97%; I2 = 99.8, 88702 participants from 9 studies). The subgroup analysis showed statistically significant differences in diabetes prevalence by the ethical sub-populations with highest in Indians (25.10%; 95% CI, 20.19%-30.35%), followed by Malays (15.25%; 95% CI, 11.59%-19.29%), Chinese (12.87%; 95% CI, 9.73%-16.37%), Bumiputeras (8.62%; 95% CI, 5.41%-12.47%) and others (6.91%; 95% CI, 5.71%-8.19%). There was no evidence of publication bias, although heterogeneity was high (I2 ranged from 0.00% to 99·8%). The quality of evidence based on GRADE was low. Results of this study suggest that a high prevalence of prediabetes and diabetes in Malaysia. The diabetes prevalence is associated with time period and increasing age. The Malaysian government should develop a comprehensive approach and strategy to enhance diabetes awareness, control, prevention, and treatment. Trial registration no. PROSPERO CRD42021255894; https://clinicaltrials.gov/.

The Relationship between MALAT1 Polymorphism rs3200401 C > T and the Risk of Overall Cancer: A Meta-Analysis.

Background and Objectives: At present, the association between the long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) polymorphism rs3200401 C > T and cancer risk remain controversial. The aim of this meta-analysis was to assess the association between rs3200401 C > T and cancer susceptibility. Materials and Methods: The databases of PubMed, EMBASE and Web of Science were searched for literature published in English until 1 September 2021. The odd ratios (ORs) and 95% confidence intervals (CIs) were applied to evaluate the strength of association in five genetic models. Heterogeneity was assessed using the Q-test and I2 test. Begg’s funnel plot and Egger’s linear regression test were conducted to assess publication bias. Meta-regression analysis was used to explore potential sources of heterogeneity. Trial sequential analysis (TSA) was performed to validate the reliability of the results. Results: A total of 10 case–control studies involving 6630 cases and 7457 controls were included in this study. The pooled ORs showed no significant association between MALAT1 rs3200401 C > T and cancer risk in five genetic models. Similarly, the association was not found in the subgroups of control source, ethnicity and study quality. In the cancer type subgroup, the results demonstrated that the T allele increased the risk of colorectal cancer (CRC) compared with the C allele. (C vs. T: OR, 1.16; 95% CI, 1.01–1.33). Conclusion: In the current meta-analysis, we found no significant association between MALAT1 polymorphism rs3200401 C > T and overall cancer risk. However, the rs3200401 C > T may be linked to a higher risk of CRC, which needs more studies to be further confirmed.

Antibiotic-resistance in medically important bacteria isolated from commercial herbal medicines in Africa from 2000 to 2021: a systematic review and meta-analysis

BackgroundAntimicrobial resistance is swiftly increasing all over the world. In Africa, it manifests more in pathogenic bacteria in form of antibiotic resistance (ABR). On this continent, bacterial contamination of commonly used herbal medicine (HM) is on the increase, but information about antimicrobial resistance in these contaminants is limited due to fragmented studies. Here, we analyzed research that characterized ABR in pathogenic bacteria isolated from HM in Africa since 2000; to generate a comprehensive understanding of the drug-resistant bacterial contamination burden in this region.MethodsThe study was conducted according to standards of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). We searched for articles from 12 databases. These were: PubMed, Science Direct, Scifinder scholar, Google scholar, HerbMed, Medline, EMBASE, Cochrane Library, International Pharmaceutical s, Commonwealth Agricultural Bureau s, African Journal Online, and Biological s. Prevalence and ABR traits of bacterial isolates, Cochran’s Q test, and the I2 statistic for heterogeneity were evaluated using MedCalcs software. A random-effects model was used to determine the pooled prevalence of ABR traits. The potential sources of heterogeneity were examined through sensitivity analysis, subgroup analysis, and meta-regression at a 95% level of significance.FindingsEighteen studies met our inclusion criteria. The pooled prevalence of bacterial resistance to at least one conventional drug was 86.51% (95% CI = 61.247–99.357%). The studies were highly heterogeneous (I2 = 99.17%; p < 0.0001), with no evidence of publication bias. The most prevalent multidrug-resistant species was Escherichia coli (24.0%). The most highly resisted drug was Ceftazidime with a pooled prevalence of 95.10% (95% CI = 78.51–99.87%), while the drug-class was 3rd generation cephalosporins; 91.64% (95% CI = 78.64–96.73%). None of the eligible studies tested isolates for Carbapenem resistance. Extended Spectrum β-lactamase genes were detected in 89 (37.2%) isolates, mostly Salmonella spp., Proteus vulgaris, and K. pneumonia. Resistance plasmids were found in 6 (5.8%) isolates; the heaviest plasmid weighed 23,130 Kilobases, and Proteus vulgaris harbored the majority (n = 5; 83.3%).ConclusionsHerbal medicines in Africa harbor bacterial contaminants which are highly resistant to conventional medicines. This points to a potential treatment failure when these contaminants are involved in diseases causation. More research on this subject is recommended, to fill the evidence gaps and support the formation of collaborative quality control mechanisms for the herbal medicine industry in Africa.

Exposure to Heavy Metals and Allergic Outcomes in Children: a Systematic Review and Meta-analysis.

It has been reported that heavy metals have adverse effects on the immune system. However, the relationship between heavy metal exposure and allergic outcomes remains unclear. This systematic review was conducted to examine whether heavy metal exposure is associated with allergic outcomes during childhood. We performed a systematic search of all relevant articles in Web of Science, EMBASE, and PubMed, from inception through to November 2020. We used odds ratio (OR) and the standard mean differences (SMDs) with 95% confidence intervals (CIs) to present estimates from individual studies. In addition, random-effects meta-analysis was used to pool the data. We also conducted the meta-regression and subgroup analysis to explore potential sources of heterogeneity. After duplicate removal, we finally included 35 articles in the systematic review and meta-analysis from an initial 11,181 articles. The overall results showed that copper (Cu) was associated with asthma (pooled SMD = 1.50, 95% CI = 0.13-2.86); in the subgroup analysis, the results indicated that lead (Pb) was associated with asthma (pooled OR = 6.27, 95% CI = 2.24-17.56), and Cu and Pb were connected with atopic dermatitis (SMD = - 1.05, 95% CI = - 1.45 to - 0.65; SMD = 5.68, 95% CI = 5.05-6.32), respectively. Mercury (Hg) was associated with atopic dermatitis (pooled OR = 1.13, 95% CI = 1.04-1.22) and wheeze (OR = 1.20, 95% CI = 1.05-1.37). The meta-analysis results indicate that Cu might be connected with childhood asthma, but not with other allergic diseases; Hg and Pb may have no association with allergic diseases during childhood. Given some limits observed in the current studies, more prospective cohort studies are still needed to verify our findings. Review registration: PROSPERO CRD42020222167.

Relationship between insertion/deletion (I/D) polymorphism of angiotensin converting enzyme (ACE) gene and susceptibility to type 2 diabetes mellitus in the Middle East and North Africa Region: A meta-analysis

Background and aimsThe association between insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene and the risk of type 2 diabetes mellitus (T2DM) remains controversial. This study aimed to assess the effect of the ACE I/D gene polymorphism on T2DM in the Middle East and North Africa region (MENA region). Material and methodsOur data was extracted from PubMed, Science Direct, and the Web of Science. The predefined inclusion criteria included only the human case-control studies of English Peer-reviewed papers containing the data on genotype distributions of ACE I/D polymorphism and the T2DM risk. Review articles, meeting abstracts, editorials, animal studies, and studies not providing genotype distribution data or without sufficient data were excluded from this work. Results of this meta-analysis were expressed using odds ratios (OR) and 95% confidence intervals (CI). Indeed, the potential sources of heterogeneity and bias were examined by the Egger regression. ResultsOf 2755 identified articles, 10 studies were selected, including 2710 patients with T2DM and 2504 control subjects. Overall, we found a significant increased risk of T2DM susceptibility and the D allele of ACE I/D gene polymorphism (OR = 1.97; 95% CI = 1.33–2.93, p = 0.0007), recessive (OR = 2.16; 95% CI = 1.27–3.67; p = 0.004), dominant (OR = 2.45; 95% CI = 1.54–3.91; p = 0.0001), homozygote (OR = 3.35; 95% CI = 1.78–6.29; p = 0.0001) and heterozygote comparisons (OR = 1.76; 95% CI = 1.07–2.88; p = 0.024). ConclusionOur result suggests that this polymorphism may contribute to the development of T2DM in the MENA Region. This result needs to be confirmed by future well-designed studies with larger sample sizes in diverse populations and ethnicities.

The effect of pro-/synbiotic supplementation on the brain-derived neurotrophic factor: a systematic review and meta-analysis of randomized controlled trials.

There is growing interest in supplementation with pro-/synbiotics for brain and mental health. Animal studies have reported that pro-/synbiotic administration can increase the brain-derived neurotrophic factor (BDNF), a key regulator of neuronal function. Nevertheless, the results obtained from human studies are inconsistent and conflicting. Therefore, we aimed to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) to investigate the impact of pro-/synbiotic supplementation on BDNF levels. Scopus, Medline, Web of Science, Cochrane Library, and Google Scholar were searched up to July 10, 2022 to find eligible RCTs. The weighted mean difference (WMD) and 95% confidence interval (CI) were computed for BDNF using a random-effects model. In the present study, 10 RCTs with 12 treatment arms consisting of 652 participants were included. The meta-analysis revealed that supplementation with pro-/synbiotics significantly increased BDNF concentrations in comparison with the placebo (WMD: 0.20 ng mL-1, 95% CI: 0.06 to 0.34, I2 = 86.6%). Moreover, subgroup analysis showed that the target population, ethnicity and the mean age of participants, the number and type of probiotic strains, administration form, and the dose and duration of pro-/synbiotic supplementation were the potential sources of heterogeneity between RCTs. In conclusion, pro-/synbiotic administration can be considered as a BDNF enhancer and a possible brain booster.

Prevalence and risk factors of Helicobacter pylori infection in military personnel: a systematic review and meta-analysis.

Helicobacter pylori infection is prevalent and recognized as a major cause of gastrointestinal diseases in the world. Previous studies on the prevalence of H. pylori infection in military personnel have shown some conflicting results. This study aimed to estimate the pooled prevalence of H. pylori infection and evaluate its risk factors in military personnel. The PubMed, EMBASE, and Cochrane Library databases were searched. We pooled the prevalence of H. pylori infection in military personnel using a random-effect model. Metaregression analysis was used to explore the sources of heterogeneity. Pooled proportion of H. pylori infection with 95% confidence interval (CI) was calculated. Sixteen studies were included. Meta-analysis showed that the overall prevalence of H. pylori infection was 32% (95% CI = 31-33) in military personnel. There was a significant heterogeneity. Metaregression analysis showed that study region (P = 0.0004) and publication year (P = 0.023) were the potential sources of heterogeneity. In the subgroup analysis by study region, the highest prevalence was found in Asia (50.2%; 95% CI = 49-51.4). In the subgroup analysis by diagnostic methods for H. pylori, the highest prevalence was found when urea breath test was employed (47.9%; 95% CI = 46.5-49.3). The most common risk factor for H. pylori infection was familial aggregation, followed by living environment and age. H. pylori infection is common in military personnel. In future, we may require appropriate population screening for H. pylori infection by multiple diagnostic tests and increase the knowledge and awareness of the bacterial transmission among military personnel.

Diagnostic Value of microRNAs for Gastric Carcinoma: a Meta-Analysis

Purpose: To systematically evaluate the potential diagnostic value of MicroRNA for gastric cancer (GC). Methods: The relevant literature was identified in databases such as PubMed, Embase and the Cochrane Library (up to December 25, 2020). Two researchers independently selected the literature based on the inclusion and exclusion criteria, extracted data, and evaluated the risk of bias. Review Manager 5.4, Meta-Disc 1.4 and STATA (version 15.1) software were performed the Meta-analysis. Results: A total of 5914 patients from 41 studies were ultimately included. The pooled sensitivity (SENS) was 0.79 (95% CI: 0.75–0.82), the pooled specificity (SPEC) was 0.87 (95% CI: 0.82–0.91), the pooled positive likelihood ratio (PLR) was 4.95 (95% CI: 3.81–6.43), the pooled negative likelihood ratio (NLR) was 0.28 (95% CI: 0.24–0.32), the pooled diagnostic odds ratio (DOR) was 20.53 (95% CI: 14.57–28.94), and the area under the curve (AUC) was 0.87 (95% CI: 0.84–0.90). A Deeks’ funnel plot demonstrates no publication bias existed (P=0.40). Meta-regression analysis showed that sample size, sample source and sample type were potential sources of heterogeneity. Conclusions: MicroRNA might be the potential biomarke diagnosing gastric cancer.