Significant Pooled Odds Ratios Research Articles

Epidemiological features of suicidal ideation among the elderly in China based meta-analysis

BackgroundStudies on the prevalence of suicidal ideation (SI) and its associated factors among the elderly in China show considerable variability. This meta-analysis aims to clarify the epidemiological features of SI in this population.MethodsWe systematically searched English and Chinese databases for relevant literature up to September 15, 2022. The extracted data facilitated the calculation of prevalence and odds ratios (ORs) for factors associated with SI among China’s elderly.ResultsWe analyzed 31 cross-sectional studies, comprising a total of 79,861 participants from over 20 provinces and municipalities. The pooled prevalence of SI was found to be 11.47% [95% confidence interval (CI): 7.82–15.71%]. Significant variations in prevalence were influenced by residence, physical health (including chronic diseases and daily living capabilities), mental health (depressive symptoms and life satisfaction), economic status, and time-specific assessment tools. Notably, the prevalence from 2011–2020 (15.59%, 95% CI: 9.08–23.44%) was almost double that of 2001–2010 (7.85%, 95% CI: 5.08–11.16%). The SI prevalence in the eastern region (8.06%, 95% CI 5.59–10.94%) was significantly lower than in the central and western regions (16.97%, 95% CI 12.04–22.53%). Fourteen factors exhibited a significant pooled OR greater than 1 (p < 0.05), and two factors had ORs less than 1 (p < 0.05), indicating notable association with SI among the elderly.ConclusionSI among China’s elderly showed relatively high prevalence and considerable heterogeneity across different characteristics and associated factors. This underscores the need for targeted intervention strategies and standardized temporal assessments of SI to effectively address suicide risk in this population.

The Association between Marital Status and Obesity: A Systematic Review and Meta-Analysis.

Obesity was included in the International Classification of Diseases in 1990 as a chronic disease characterized by the excessive accumulation of body fat and a body mass index (BMI) greater than 30 kg/m2. This systematic review was aimed to examine the role of marital status in determining body mass index and the risk of obesity. We performed a systematic literature search using three databases (PubMed (Medline), Embase, and Google Scholar) with the search query. Of the 105 studies included in the systematic review, 76 studies (72%) reported a greater risk of obesity in married individuals compared to unmarried individuals. A meta-analysis of 24 studies included a total population of 369,499 participants: 257,257 married individuals (40,896 of whom had obesity) and 112,242 comparison subjects (single, divorced, or widowed individuals, 15,084 of whom had obesity). Odds ratios for obesity found a significant pooled odds ratio for obesity in married individuals compared with controls (OR 1.70; 95% CI 1.38-2.10). The socioeconomic environment was not the same throughout the period of studies analyzed. The odds of obesity in married individuals during economic crises was greater than during the period between crises: OR 2.56 (95% CI 2.09-3.13) during crises vs. OR 1.55 (95% CI 1.24-1.95) between crises. The results of this review confirm the importance of considering marital status in determining the risk of obesity.

Maternal ApoE genotype and risk of recurrent pregnancy loss: An updated systematic review and meta-analysis.

In order to clarify the role of the maternal apolipoprotein E (ApoE) genotype and the risk of recurrent pregnancy loss (RPL), we herein performed an updated systematic review and meta-analysis to reevaluate the evidence on this association. A comprehensive literature search was performed on PubMed, Web of Knowledge and the Cochrane library up to September 2022. Methodological study quality was assessed using the Newcastle-Ottawa Scale and the credibility of significant pooled odds ratios (ORs) was estimated by the false positive report probability and the Bayesian false discovery probability. Twelve studies published from 2009 to 2022 fulfilled the inclusion criteria. In the overall analysis, the ε4 allele was found to confer an increased risk of RPL compared to the ε3 allele (OR 1.60, 95% CI 1.00-2.55, p = 0.049) and women carrying the ApoE ε4 allele displayed a higher risk of RPL compared with those carrying the ε2 and ε3 alleles (OR 1.75, 95% CI 1.06-2.87, p = 0.028). Subgroup analysis based on subjects' ethnicity revealed that these associations were restricted to the Asian population (ε4 allele vs. ε3 allele, OR 5.93, 95% CI 1.79-19.61, p = 0.004; ε4 allele carriers vs. carriers of ε2 and ε3 alleles, OR 8.42, 95% CI 1.47-48.12, p = 0.017). None of the associations detected were found to be noteworthy under false positive report probability or Bayesian false discovery probability at a prior probability of 0.001. This updated meta-analysis highlights an association between maternal ApoE genotype and RPL risk in Asians, but not in Caucasians. Further case-control studies are warranted in women of Asian ancestry to exclude the possibility of false-positive findings.

Metabolic Disorders and Risk of Portal Vein Thrombosis in Liver Cirrhosis: A Systematic Review and Meta-Analysis.

Portal vein thrombosis is considered to be an indicator of worse outcomes in patients with hepatic cirrhosis. More and more evidence shows that metabolic disorders are noticeable pro-thrombotic factors. However, whether or not metabolic disorders increase the risk of cirrhotic portal vein thrombosis is controversial. We aim to quantify the magnitude of the association between metabolic disorders and the risk of cirrhotic portal vein thrombosis. Databases were searched for papers to identify studies in which metabolic disorders were compared in liver cirrhosis with or without portal vein thrombosis. Based on data from the eligible studies, metabolic disorders related to portal vein thrombosis included diabetes mellitus, nonalcoholic fatty liver disease, hypercholesterolemia, and body mass index. Pooled adjusted odds ratios with 95% CIs were calculated. Data for 22 studies with a total of 57 371 portal vein thrombosis cases and 3 979 015 participants were included. Statistically significant pooled odds ratios for portal vein thrombosis were obtained for diabetes mel- litus (odds ratio 1.80, 95% CI 1.42-2.28), nonalcoholic fatty liver disease (odds ratio 1.61, 95% CI 1.34-1.95), and hypercholesterolemia (odds ratio 3.59, 95% CI 1.83-7.03). Body mass index was likely irrelevant with cirrhotic portal vein thrombosis (odds ratio 1.01, 95% CI 0.87-1.17), both in overall and subgroup meta-analyses. Significant heterogeneities among studies were observed, except for the hypercholesterolemia group. Metabolic disorders, such as diabetes mellitus, nonalcoholic fatty liver disease, and hypercholesterolemia, increased the risk of portal vein thrombosis in cirrhotic patients by 1.80-fold, 1.61-fold, and 3.59-fold, respectively. Body mass index did not appear to be a risk predictor of cirrhotic portal vein thrombosis. Further, well-designed clinical and mechanistic studies are required to strengthen the arguments, especially in obese patients.

Associations of osteoprotegerin (OPG) TNFRSF11B gene polymorphisms with risk of fractures in older adult populations: meta-analysis of genetic and genome-wide association studies.

Fractures in older people usually result from compromised bone integrity. The multifactorial aetiology of fractures includes both genetic and environmental factors. Inconsistency of reported associations of osteoprotegerin (OPG) (TNFRSF11B) polymorphisms with fracture in the older adult population warranted a meta-analysis to determine more precise estimates. We searched for all available literature on OPG (TNFRSF11B) and fracture. Four polymorphisms were examined, one exonic (rs2073618) and three intronic (rs3134069, rs3134070 and rs3102735). The first two intron polymorphisms were combined (OPGI: osteoprotegerin intron) on account of complete linkage disequilibrium. Risks were estimated with odds ratios (ORs) and 95% confidence intervals (CIs) using the allele-genotype model that included variant (var), wild-type (wt) and heterozygote (het). Multiple comparisons were Bonferroni-corrected. We used meta-regression to examine sources of heterogeneity. Zero heterogeneity (homogeneity: I2 = 0%) and high significance (Pa < 0.00001) were the criteria for strength of evidence. Significant outcomes were subjected to sensitivity analysis and publication bias assessment. From 13 articles (11 genetic association and two genome-wide), this meta-analysis generated five significant pooled ORs, all indicating reduced risks (ORs 0.44-0.87). Of the five, four highly significant comparisons (Pa ≤ 0.00001-0.002) survived the Bonferroni correction, one in rs2073618 het model of the postmenopausal women (OR 0.87, 95% CI 0.81-0.92, I2 = 0%) and the other three in OPGI wt model of the overall analysis, ≥ 60 y and Western subjects (ORs 0.63-0.71, 95% CI 0.47-0.86, I2 = 97-99%). These findings were consistent, had high significance and high statistical power and were robust and without evidence of publication bias. Four covariates (year of publication, study quality, fracture type/site and sample size) were the sources of heterogeneity in the OPGI overall outcomes (Pa = 0.0001-0.03). Evidence showed that the OPG (TNFRSF11B) polymorphisms reduced the risk for fracture in older adults, particularly protective among postmenopausal women, ≥ 60 y and Western subjects.

Toxoplasma gondii infection and spontaneous abortion: A systematic review and meta-analysis

Toxoplasmosis is one of the most common parasitic infections in humans, which is caused by Toxoplasma gondii. It is usually asymptomatic but primary infection in a pregnant woman can cause severe consequences in the fetus such as miscarriage. This study aimed to estimate the global prevalence of T. gondii infection in women with spontaneous abortion. It also evaluates the possible relationship between recent Toxoplasma infection and miscarriage. Five electronic databases were reviewed. We used the random effects model and 95% confidence intervals(CI) to determine the overall prevalence and odds ratio (OR). Heterogeneity was calculated using Cochran's Q test and I2 statistic. The included studies were divided into three sub-groups based on antibody class against T. gondii and the existence of parasite DNA. Based on PCR, the pooled random-effects estimates that the prevalence of T. gondii infection in women with abortion was 10% (95% CI 7–14%). The pooled random effect favored a statistically significant increased risk of latent Toxoplasma infection [OR = 1.84; 95% CI: 1.41–2.40, P < 0.001] and recent infection [OR = 3.72; 95% CI: 2.21–6.26, P < 0.001] in women with spontaneous abortions. In recent infections, significant pooled ORs of positive association were observed in women with miscarriage [OR = 4.2; 95% CI: 2.04–8.85; χ2 = 17.2; I2 = 42.0%, P = 0.07]. This study demonstrates that recent T. gondii infection is associated with an elevated risk of spontaneous abortion. Further studies concerning all risk factors related to toxoplasmosis, and undertaking confirmatory tests at the time of abortion should be performed to investigate the impact of T. gondii infection and spontaneous abortion.

CTLA-4 rs231775 and risk of acute renal graft rejection: an updated meta-analysis with trial sequential analysis

Contrasting results exist on the association between CTLA-4 rs231775 and acute rejection in kidney transplant recipients. We herein conducted an updated systematic review with meta-analysis and trial sequential analysis (TSA) to clarify this relationship and to establish whether the current evidence is sufficient to draw firm conclusions. In addition, noteworthiness of significant pooled odds ratios (ORs) was estimated by false positive report probability (FPRP). A comprehensive search was performed through PubMed, Web of Knowledge, Cochrane Library and Open Grey up to October 2019. Fifteen independent cohorts, including a total of 5,401 kidney transplant recipients, were identified through the systematic review. Overall, no association was detected with the allelic (OR 1.07, 95% CI 0.88–1.30, P = 0.49), dominant (OR 0.94, 95% CI 0.73–1.22, P = 0.66) or the recessive (OR 1.18, 95% CI 0.97–1.43, P = 0.096) model of CTLA-4 rs231775. In each genetic model, the cumulative Z-curve in TSA crossed the futility boundary and entered the futility area. In addition, none of the significant genetic comparisons detected in the subsequent and sensitivity analyses or in previously reported meta-analyses were found to be noteworthy by FPRP. In conclusion, this study provides strong evidence that CTLA-4 rs231775 is not a clinically-relevant genetic risk determinant of acute rejection after renal transplantation.

Maternal Exposure to Air Pollutions and Risk of Autism in Children

TPS 731: Neurological effects in children, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background: The number of children diagnosed with autism spectrum disorder (ASD) has increased. This systematic review and meta-analysis aimed to summarize the association between maternal exposure to outdoor air pollution and ASD in children. Methods: A systematic literature search in three databases (Medline, Embase, and Web of Science) was performed using subject headings related to ASD and maternal exposure to air pollution. Eligible studies were screened based on predetermined criteria, and risk of bias was assessed by the Newcastle-Ottawa Scale. For meta-analyses, the studies were grouped by air pollutant and exposure time (prenatal period and trimesters). Within-group studies were standardized by log odds ratio (OR) and then combined by three meta-analysis methods: frequentist fixed and random effects models, and Bayesian random effects model due to the small number of studies. Results: The initial search identified 1,302 papers, of which 20 studies remained for final analysis after duplicates and ineligible studies were removed. Of the 20 studies, 9, 11, 10, and 6 studies, respectively, investigated the association of ASD with PM2.5, PM10, NO2, and ozone. The frequentist and Bayesian random effects models resulted in different statistical significance. For prenatal period, frequentist meta-analysis returned significant pooled ORs for PM2.5 (1.073 with 95% confidence interval (1.008, 1.142)) and ozone (1.010: (1.002, 1.017)), but Bayesian meta-analysis showed ORs with wider uncertainty for PM2.5 (1.075 with 95% posterior interval (0.966, 1.222)) and ozone (1.010: (0.907, 1.133)). Trimester 3 appeared to have higher pooled ORs for PM2.5, PM10, NO2, and ozone. Patterns in the time-varying associations over the trimester were inconsistent, as between-study differences were apparent. Conclusions: There is marginal evidence for positive associations between maternal exposure to PM2.5, but not PM10, NO2, and ozone, and ASD development in children during pregnancy. However, trends in associations over trimesters were inconsistent between studies and between air pollutants.

Maternal exposure to air pollution and risk of autism in children: A systematic review and meta-analysis

BackgroundThe number of children diagnosed with autism spectrum disorder (ASD) has been increasing. Previous studies suggested potential association between pregnancy air pollution exposure and ASD. This systematic review and meta-analysis is intended to summarize the association between maternal exposure to outdoor air pollution and ASD in children by trimester based on recent studies. MethodsA systematic literature search in 3 databases (Medline, Embase, and Web of Science) was performed using subject headings related to ASD and air pollution since 2007. Eligible studies were screened and evaluated based on predetermined criteria. For meta-analyses, the studies were grouped by air pollutant and exposure time (prenatal period and trimesters). Within-group studies were standardized by log odds ratio (OR) and then combined by three meta-analysis methods: frequentist fixed and random effects models, and Bayesian random effects model. ResultsInitial search identified 1564 papers, of which 25 studies remained for final analysis after duplicates and ineligible studies were removed. Of the 25 studies, 13, 14, 12, and 7 studies investigated ASD in children associated with PM2.5, PM10, NO2, and ozone, respectively. The frequentist and Bayesian random effects models resulted in different statistical significance. For prenatal period, frequentist meta-analysis returned significant pooled ORs with 95% confidence intervals, 1.06(1.01,1.11) for PM2.5 and 1.02(1.01,1.04) for NO2, whereas Bayesian meta-analysis showed similar ORs with wider 95% posterior intervals, 1.06(1.00,1.13) for PM2.5 and 1.02(1.00,1.05) for NO2. Third trimester appeared to have higher pooled ORs for PM2.5, PM10, and ozone, but patterns in the time-varying associations over the trimester were inconsistent. ConclusionsFor positive association between maternal exposure to ambient air pollution and ASD in children, there is some evidence for PM2.5, weak evidence for NO2 and little evidence for PM10 and ozone. However, patterns in associations over trimesters were inconsistent among studies and among air pollutants.

Different Associations between DC-SIGN Promoter-336G/A (rs4804803) Polymorphism with Severe Dengue in Asians and South-Central Americans: a Meta-Analysis.

Objective: This study was conducted to identify the association between rs4804803 polymorphism in DC-SIGN with the susceptibility of severe dengue. Methods: A comprehensive search was conducted to identify all eligible papers in PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Google Scholar. Odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were used to assess the association. Subgroup analyses were performed by ethnicity. Sensitivity analyses were performed through employing different statistical models (fixed versus random effect model). Results: A total of nine papers and 12 studies, with 1520 severe dengue and 1496 clinical dengue infection were included. The overall meta-analysis revealed significant associations between rs4804803 and severe dengue under the recession (GG versus GA/AA: OR = 0.44, 95%CI, 0.23–0.82) and a codominant model (GG versus AA: OR = 0.43, 95%CI, 0.23–0.81), but sensitivity analysis indicated that the significant pooled ORs were not robust. The subgroup analysis suggested that the carrier of G in rs4804803 was a risk factor for severe dengue under dominant (GG/GA versus AA: OR = 1.86,95%CI, 1.01–3.45), superdominant (GA versus GG/AA: OR = 1.81,95%CI, 1.02–3.21) and a codominant (GA versus AA: OR=1.82,95%CI, 1.02–3.26) models in Asians, while it was a protective factor for severe dengue in South-central Americans under recessive (GG versus GA/AA: OR = 0.27,95%CI, 0.10–0.70) and codominant (GG versus AA: OR=0.24,95%CI, 0.09–0.64) models. The results from subgroup analysis were robust. Conclusions: Dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) promoter-336G/A (rs4804803) polymorphism is association with severe dengue, and it acts in different directions for Asians and South-central Americans.

The association of Vitamin D levels to advanced liver fibrosis and response to hepatitis C therapy

The importance of vitamin D in many diseases has come to light recently. In the Middle East, there is a prevalence of low vitamin D levels. Evidence linking vitamin D to the parthogenesis of chronic hepatitis C is present. The aim of this study is to analyze the relationship of vitamin D levels with advanced liver fibrosis (ALF) CHC treatment‐naive patients and sustained virology response (SVR) in CHC patients on PEGylated interferon alpha plus ribavirin (pegIFNa/ribavirin) therapy.Materials and methodsA meta‐analysis of eligible studies published from 1999 to 2014 was conducted. Databases such as PubMed, SCOPUS, Web of Science, and the Cochrane Library were used. Studies assessed included data assessment between plasma/serum vitamin D levels and its relation to ALF and/or SVR. Pooled odds ratios (ORs) were estimated by either fixed or random effects models. Eighteen studies were selected from the literature search, seven for ALF (1,099 patients) and 11 for SVR (2,580 patients). For liver fibrosis, low vitamin D status was related to a diagnosis of ALF, with the cutoffs of 10 ng/mL (OR=2.37, 95% confidence interval, [CI] = 1.20, 4.72) and 30 ng/ml (OR=2.22, 95% CI = 0.99, 3.97) being significant, and a near‐significance for 20 ng/ml.ResultsRegarding SVR, there was a significant heterogeneity among studies (P&lt; 0.001). A significant association with SVR for a vitamin D cutoff of 20 ng/mL (OR=0.53, 95% CI=0.31, 0.91) was present. When meta‐analysis was performed excluding the outliers, significant pooled ORs were found for all patients (10 ng/mL [OR=0.48, 95% CI=0.34, 0.67] and 20 ng/mL [OR=0.58, 95% CI=0.45, 0.76]) and GT1/4 patients (10 ng/mL [OR=0.53, 95% CI=0.34, 0.81] and 20 ng/mL [OR=0.54, 95% CI=0.39, 0.74]).ConclusionLow vitamin D status in CHC patients is associated with a higher likelihood of having ALF and lower odds of achieving SVR following pegIFN/ribavirin therapy. Also vitamin D supplementation could improve the SVR rate in patients treated with pegIFN/ribavirin.Support or Funding InformationThis work was supported and funded by Ras Alkhaimah medical and health science universityThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

NLRP3 p.Q705K and CARD8 p.C10X single nucleotide polymorphisms are not associated with susceptibility to rheumatoid arthritis: a meta-analysis.

Genetic factors have a substantial contribution to the pathogenesis of rheumatoid arthritis (RA). Single nucleotide polymorphisms of NLRP3 p.Q705K and CARD8 p.C10X are two gene mutations that have been linked to many diseases. Here we carried out a meta-analysis to identify their association with susceptibility to RA. Relevant studies were identified from databases, including PubMed, Cochrane Library, EMBase, Elsevier Science Direct, Web of Science, SpringerLink, and so on. Data extracted from selected studies were analyzed using the Version 12.0 STATA software. Pooled odds ratios (ORs) were calculated as the effect sizes for comparisons. In total, six case-control studies from five articles that contained 2705 RA patients and 2711 healthy controls were included. (i) The NLRP3 p.Q705K polymorphism in allelic model (OR=0.908), genotypic models (OR1=0.786; OR2=0.916; OR3=0.729), dominant (OR=0.909) and recessive models (OR=0.778) were not associated with the risk of RA (all P>0.05). (ii) The CARD8 p.C10X polymorphism in allelic model (OR=0.995,), genotypic models (OR1=0.997; OR2=1.052; OR3=0.950), dominant (OR=1.033) and recessive models (OR=0.963) were not associated with the risk of RA (all P>0.05). (iii) When compared with combined genotype CARD8/NLRP3 AA/CC, none of the other combined genotypes had significant pooled ORs (all P>0.05). (iv) Individuals carrying at least one variant allele at each of the two loci showed no more susceptibility to RA than those carrying only wild-type alleles at both the NLRP3 p.Q705K and CARD8 p.C10X loci (OR=1.056, P>0.05). NLRP3 p.Q705K and CARD8 p.C10X polymorphisms were not associated with the susceptibility to RA, separately or in combined forms.

Ischemic Stroke and Six Genetic Variants in CRP, EPHX2, FGA, and NOTCH3 Genes: A Meta-Analysis

Ischemic stroke (IS) is a leading cause of death and disability worldwide. As genetic heritability for IS is estimated at about 35%-40%, the identification of genetic variants associated with IS risk is of great importance. The main objective of this study was to carry out a meta-analysis for polymorphisms in CRP, EPHX2, FGA, and NOTCH3 genes and the risk for IS. Literature search for 6 candidate polymorphisms and IS was conducted using HuGE Navigator, PubMed, and Google Scholar databases. Meta-Analyst program was used to calculate pooled odds ratios (ORs) with a random effects model. Twenty-five published studies for 6 candidate polymorphisms were included: CRP-rs1800947 (5 studies), CRP-rs1205 (3 studies), EPHX2-rs751141 (5 studies), FGA-rs6050 (6 studies), NOTCH3-rs3815188 (3 studies), and NOTCH3-rs1043994 (3 studies), for a total number of 7,825 IS cases and 56,532 control subjects. We did not find significant pooled ORs (P values > .05) for any of the genetic variants evaluated in this work. Our meta-analysis results did not show significant associations between these 6 polymorphisms in 4 candidate genes and IS, despite the functional role of some of these single nucleotide polymorphisms (e.g., rs6050 in FGA gene). Future studies are needed to identify additional main genetic risk factors for IS in different populations.

Hygiene and mental health among middle school students in India and 11 other countries.

The Global School-based Student Health Survey (GSHS) collects data from early adolescents who are approximately 13-15 years old and enrolled in middle schools (also known as junior secondary schools). We used logistic regression models to examine the associations between self-reported hygiene practices and mental health status as assessed by the 2007 India GSHS. Then, we used meta-analysis to compare the results from India with those from 11 other GSHS-participating countries in Asia and Africa (Djibouti, Indonesia, Jordan, Kenya, Lebanon, Myanmar, the Philippines, Tanzania, Thailand, Uganda, and the United Arab Emirates). Among 7904 middle school students in India, 25.5% reported symptoms of depression, 8.6% reported loneliness, and 7.8% reported anxiety-related insomnia. Both males and females who reported symptoms of depression had an increased likelihood of poor hand and oral hygiene, including washing their hands rarely or never and brushing their teeth less than daily. The meta-analysis for this association yielded statistically significant pooled odds ratios for both boys and girls. In girls, loneliness was also associated with poor hand and oral hygiene. Reduced mental health status in adolescents may lead to worse hygiene behaviors and an increased risk of infections. Teachers, parents, healthcare workers, and other adults who observe suboptimal hygiene status in an adolescent should consider whether this indicates a mental health issue that requires clinical services.

Meta-analysis of six genes (BDNF, DRD1, DRD3, DRD4, GRIN2B and MAOA) involved in neuroplasticity and the risk for alcohol dependence

BackgroundAlcohol-related problems have a large impact on human health, accounting for around 4% of deaths and 4.5% of disability-adjusted life-years around the world. Genetic factors could explain a significant fraction of the risk for alcohol dependence (AD). Recent meta-analyses have found significant pooled odds ratios (ORs) for variants in the ADH1B, ADH1C, DRD2 and HTR2A genes. MethodsIn the present study, we carried out a meta-analysis of common variants in 6 candidate genes involved in neurotransmission and neuroplasticity: BDNF, DRD1, DRD3, DRD4, GRIN2B and MAOA. We carried out a systematic search for published association studies that analyzed the genes of interest. Relevant articles were retrieved and demographic and genetic data were extracted. Pooled ORs were calculated using a random-effects model using the Meta-Analyst program. Dominant, recessive and allelic models were tested and analyses were also stratified by ethnicity. ResultsForty two published studies were included in the current meta-analysis: BDNF-rs6265 (nine studies), DRD1-rs4532 (four studies), DRD3-rs6280 (eleven studies), DRD4-VNTR (seven studies), GRIN2B-rs1806201 (three studies) and MAOA-uVNTR (eight studies). We did not find significant pooled ORs for any of the six genes, under different models and stratifying for ethnicity. ConclusionsIn terms of the number of candidate genes included, this is one of the most comprehensive meta-analyses for genetics of AD. Pooled ORs did not support consistent associations with any of the six candidate genes tested. Future studies of novel genes of functional relevance and meta-analyses of quantitative endophenotypes could identify further susceptibility molecular factors for AD.

Relationship of vitamin D status with advanced liver fibrosis and response to hepatitis C virus therapy: A meta-analysis

There is growing evidence that vitamin D is related to chronic hepatitis C (CHC) pathogenicity. We analyzed the relationship of vitamin D status with advanced liver fibrosis (ALF) in CHC treatment-naïve patients and sustained virologic response (SVR) in CHC patients on pegylated interferon alpha plus ribavirin (pegIFNα/ribavirin) therapy. We performed a meta-analysis of all eligible studies published to date (April, 2014) in PubMed, SCOPUS, LILACS, and the Cochrane Library, assessing plasma/serum vitamin D levels related to ALF and/or SVR. Pooled odds ratios (ORs) were estimated by either fixed or random effects models. Fourteen studies were selected from the literature search, seven for ALF (1,083 patients) and 11 for SVR (2,672 patients). For liver fibrosis, low vitamin D status was related to a diagnosis of ALF, with the cutoffs of 10 ng/mL (OR=2.37, 95% confidence interval [CI]=1.20, 4.72) and 30 ng/mL (OR=2.22, 95% CI=1.24, 3.97) being significant, and a near-significance for 20 ng/mL (OR=1.44, 95% CI=0.99, 2.12). Regarding SVR, a significant heterogeneity among studies was found (P<0.001), and we only found a significant association with SVR for a vitamin D cutoff of 20 ng/mL (OR=0.53, 95% CI=0.31, 0.91). When meta-analysis was performed excluding the outliers, significant pooled ORs were found for all patients (10 ng/mL [OR=0.48, 95% CI=0.34, 0.67] and 20 ng/mL [OR=0.58, 95% CI=0.45, 0.76]) and GT1/4 patients (10 ng/mL [OR=0.53, 95% CI=0.34, 0.81] and 20 ng/mL [OR=0.54, 95% CI=0.39, 0.74]). Low vitamin D status in CHC patients is associated with a higher likelihood of having ALF and lower odds of achieving SVR following pegIFNα/ribavirin therapy.

A systematic review and meta-analysis of the effects of antibiotic consumption on antibiotic resistance

BackgroundGreater use of antibiotics during the past 50 years has exerted selective pressure on susceptible bacteria and may have favoured the survival of resistant strains. Existing information on antibiotic resistance patterns from pathogens circulating among community-based patients is substantially less than from hospitalized patients on whom guidelines are often based. We therefore chose to assess the relationship between the antibiotic resistance pattern of bacteria circulating in the community and the consumption of antibiotics in the community.MethodsBoth gray literature and published scientific literature in English and other European languages was examined. Multiple regression analysis was used to analyse whether studies found a positive relationship between antibiotic consumption and resistance. A subsequent meta-analysis and meta-regression was conducted for studies for which a common effect size measure (odds ratio) could be calculated.ResultsElectronic searches identified 974 studies but only 243 studies were considered eligible for inclusion by the two independent reviewers who extracted the data. A binomial test revealed a positive relationship between antibiotic consumption and resistance (p < .001) but multiple regression modelling did not produce any significant predictors of study outcome. The meta-analysis generated a significant pooled odds ratio of 2.3 (95% confidence interval 2.2 to 2.5) with a meta-regression producing several significant predictors (F(10,77) = 5.82, p < .01). Countries in southern Europe produced a stronger link between consumption and resistance than other regions.ConclusionsUsing a large set of studies we found that antibiotic consumption is associated with the development of antibiotic resistance. A subsequent meta-analysis, with a subsample of the studies, generated several significant predictors. Countries in southern Europe produced a stronger link between consumption and resistance than other regions so efforts at reducing antibiotic consumption may need to be strengthened in this area. Increased consumption of antibiotics may not only produce greater resistance at the individual patient level but may also produce greater resistance at the community, country, and regional levels, which can harm individual patients.

Meta‐analysis of type and complexity of a secondary task during walking on the prediction of elderly falls

Dual-tasking probes divided attention and causes performance changes that are associated with an increased risk for falls in the elderly. There is no systematic review investigating the effect of task type and complexity on the prediction of elderly falls. This article synthesizes research evidence regarding this issue on the contents of dual-tasking walking. Relevant studies were systematically identified from electronic databases of Medline, PubMed, CINAHL, Cochrane CENTRAL and PsycINFO, and the reference lists of identified articles. The selection criteria were defined a priori. Two independent reviewers classified task types based on properties for cognitive demand, assessed the methodological quality with a customized checklist, and calculated the odds ratio of fall prediction. There was one study of reaction time, one of discrimination and decision-making, 10 of mental tracking, three of verbal fluency and five of manual tasks. The methodological heterogeneity was manifested in the selection criteria, faller classification, tasks and measures, resulting in substantial heterogeneity (I(2) 87-92%). Meta-analyses resulted in a significant pooled odds ratio 1.33 (95% CI 1.18-1.50). The mental tracking task was the only type that yielded a significant odds ratio 3.30 (95% CI 2.00-5.44). Running meta-analyses separately for simple and difficult mental tracking task showed similar odds ratios. The mental tracking task yielded significant dual-task-related changes for fall prediction. Most studies successively used an appropriate level of task complexity specific to the specified population of interest. More research is required for definite conclusions regarding the effect of task type and complexity.

How to weight chronic diseases in multimorbidity indices? Development of a new method on the basis of individual data from five population-based studies

ObjectiveIn multimorbidity indices, chronic conditions are often weighted according to their severity or their impact on different outcomes. These weights are mostly developed on the basis of only one study population by using very specific study participants, such as hospital patients. To overcome the limited validity of the indices, mean weights across five population-based studies were calculated according to the impact of diseases on self-reported health status. Study Design and SettingIndividual data was provided from the National Health Interview and Examination Survey (n=1,010), Dortmund Health Study (n=281), Memory and Morbidity in Augsburg Elderly Study (n=385), Survey of Health, Aging and Retirement in Europe Study (n=1,278), and Study of Health in Pomerania Study (n=962). By using logistic regression analysis, odds ratios (ORs) were calculated for reporting a fair or poor health status resulting from one of 10 different chronic conditions compared with a reference group without the specific disease, controlling for age and sex. If the results were homogenous across studies (I2<40%), significant pooled ORs were considered valid weights for a multimorbidity index. ResultsMyocardial infarction has the highest impact on self-reported health status across studies with a pooled OR of 3.9, followed by chronic obstructive pulmonary disease (pooled OR: 3.1). A medium impact was observed for arthrosis, asthma, diabetes mellitus, and osteoporosis. ConclusionThis method provided valid weights for seven chronic conditions.

A meta-analysis of genotypes and haplotypes of methylenetetrahydrofolate reductase gene polymorphisms in acute lymphoblastic leukemia

A meta-analysis of case-control studies that investigated the association between the C677T and/or A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and acute lymphoblastic leukemia (ALL) was carried out. Pooled odds ratios (OR) of various genetic contrasts of each polymorphism were estimated using random (RE) and fixed effects (FE) models. Pooled ORs for combined genotypes and haplotypes were estimated after adjustment for study effect using a log-linear model and the expectation-maximization algorithm in combination with log-linear modeling, respectively. The recessive model for allele 1298C produced a rather marginal association: RE OR: 0.67; 95% confidence interval (CI): 0.46-0.99 and FE OR: 0.64; 95% CI: 0.49-0.84. In Caucasians, the results of the recessive model for allele 1298C was consisted with a protective effect of ALL development: FE OR: 0.63; 95% CI: 0.46-0.87. In childhood ALL, according to the results of the allele contrast and the recessive model for 677T allele it was conceivable that a protective effect exist: RE OR = 0.74; 95% CI: 0.57-0.96 and RE OR: 0.69; 95% CI: 0.51-0.94, respectively. The combined genotypes produced significant pooled OR for the 677CC/1298CC relative to 677CC/1298AA (OR: 0.54; 95% CI: 0.36-0.80). The haplotype 677C/1298C might be more protective to ALL relative to haplotype 677C/1298A (OR: 0.77; 95% CI: 0.61-0.97). When studies not in Hardy-Weinberg equilibrium (HWE) were corrected to account for departures from HWE, then, the pattern of results remained the same. Overall, there is high heterogeneity between the studies in both polymorphisms. A differential magnitude of effect in large versus small studies and alteration of early extremes effects existed.