Prevention of preterm birth with vaginal progesterone or 17-alpha-hydroxyprogesterone caproate: a critical examination of efficacy and safety

Progestogens are the first drugs to demonstrate reproducibly a reduction in the rate of early preterm birth. The efficacy and safety of progestogens are related to individual pharmacologic properties of each drug within this class of medication and characteristics of the population that is treated. The synthetic 17-hydroxyprogesterone caproate and natural progesterone have been studied with the use of a prophylactic strategy in women with a history of preterm birth and in women with a multiple gestation. Evidence from a single large comparative efficacy trial suggests that vaginal natural progesterone is superior to 17-hydroxyprogesterone caproate as a prophylactic treatment in women with a history of mid-trimester preterm birth. Progestogen therapy is indicated for women with this highest risk profile based on evidence from 2 trials. A therapeutic approach based on the identification of a sonographic short cervix has been studied in several phase III trials. Independent phase III trials and an individual patient metaanalysis suggest that vaginal progesterone is efficacious and safe in women with a singleton and a short cervix. Two trials that tested 17-hydroxyprogesterone caproate in women with a short cervix showed no benefit. No consistent benefit for the prophylactic or therapeutic use of progestogens has been demonstrated in larger trials of women whose pregnancies were complicated by a multiple gestation (twins or triplets), preterm labor, or preterm rupture of membranes. Unfortunately, several large randomized trials in multiple gestations have identified harm related to 17-hydroxyprogesterone caproate exposure, and the synthetic drug is contraindicated in this population. The current body of evidence is evaluated by the Grading of Recommendations Assessment, Development, and Evaluation guidelines to derive the strength of recommendation in each of these populations. A large confirmatory trial that is testing 17-hydroxyprogesterone caproate exposure in women with a singleton pregnancy and a history of preterm birth is near completion. Additional study of the efficacy and safety of progestogens is suggested in well-selected populations based on the presence of biomarkers.

Systematic review and metaanalysis of perinatal outcomes after radiofrequency ablation and bipolar cord occlusion in monochorionic pregnancies

The aim of this study was to analyze perinatal outcomes after selective reduction in monochorionic pregnancies with the use of either radiofrequency ablation (RFA) or bipolar cord occlusion (BCO). This was a systematic review and metaanalysis that included all studies with ≥5 cases that described perinatal outcomes after BCO or RFA that were identified in PubMed, Embase, Web of Science, COCHRANE, CINAHL, Academic Search Premier, Science Direct, and MEDLINE that were published between 1965 and July 2014. For count data, incidence risk ratios (IRR; 95% confidence interval [CI]) were calculated with BCO as the reference standard. The analysis included 481 cases of BCO and 320 cases of RFA from 17 studies. The mean median gestations at procedure were 21.1 ± 1.2 weeks (BCO) and 18.8 ± 2.5 weeks (RFA; P = .03). The rate of cotwin death was higher in the RFA group (14.7%) vs the BCO group (10.6%; IRR, 1.38; 95% CI, 0.93-2.05; P = .11). The live birth rate was 81.3% for the RFA group and 86.7% in the BCO group (IRR, 0.93; 95% CI, 0.80-1.09; P = .41). BCO had higher neonatal death rates (8.1%) vs RFA (4.5%; IRR, 0.56; 95% CI, 0.30-1.04; P = .07). Overall survival was 76.8% for RFA and 79.1% for BCO (IRR, 0.97; 95% CI, 0.82-1.14; P = .72); however, none of these differences were statistically significant. Preterm premature rupture of membranes occurred in 17.7% of RFA cases and 28.2% of the BCO cases (IRR, 0.63; 95% CI, 0.43-0.91; P = .01). The mean median gestational age at delivery was 34.7 ± 1.7 weeks in the RFA group and 35.1 ± 1.6 weeks in the BCO group. Our data do not demonstrate clearly the superiority of 1 procedure over the other. The clinical situation and preference of the operator are important considerations. Rates of preterm delivery and preterm premature rupture of membranes remain substantial for both procedures.

Global alteration of ocean ecosystem functioning due to increasing human CO2 emissions

Rising anthropogenic CO2 emissions are anticipated to drive change to ocean ecosystems, but a conceptualization of biological change derived from quantitative analyses is lacking. Derived from multiple ecosystems and latitudes, our metaanalysis of 632 published experiments quantified the direction and magnitude of ecological change resulting from ocean acidification and warming to conceptualize broadly based change. Primary production by temperate noncalcifying plankton increases with elevated temperature and CO2, whereas tropical plankton decreases productivity because of acidification. Temperature increases consumption by and metabolic rates of herbivores, but this response does not translate into greater secondary production, which instead decreases with acidification in calcifying and noncalcifying species. This effect creates a mismatch with carnivores whose metabolic and foraging costs increase with temperature. Species diversity and abundances of tropical as well as temperate species decline with acidification, with shifts favoring novel community compositions dominated by noncalcifiers and microorganisms. Both warming and acidification instigate reduced calcification in tropical and temperate reef-building species. Acidification leads to a decline in dimethylsulfide production by ocean plankton, which as a climate gas, contributes to cloud formation and maintenance of the Earth's heat budget. Analysis of responses in short- and long-term experiments and of studies at natural CO2 vents reveals little evidence of acclimation to acidification or temperature changes, except for microbes. This conceptualization of change across whole communities and their trophic linkages forecast a reduction in diversity and abundances of various key species that underpin current functioning of marine ecosystems.

Placental implantation abnormalities and risk of preterm delivery: a systematic review and metaanalysis

We sought to evaluate the extent of the association between placental implantation abnormalities (PIA) and preterm delivery in singleton gestations. We conducted a systematic review of English-language articles published from 1980 onward using PubMed, MEDLINE, EMBASE, CINAHL, LILACS, and Google Scholar, and by identifying studies cited in the references of published articles. Search terms were PIA defined as ≥ 1 of the following: placenta previa, placenta accreta, vasa previa, and velamentous cord insertion. Observational and experimental studies were included for review if data were available regarding any of the aforementioned PIA and regarding gestational age at delivery or preterm delivery. Case reports and case series were excluded. Studies were reviewed and data extracted. The primary outcome was gestational age at delivery or preterm delivery <37 weeks' gestation. Secondary outcomes included birthweight, 1- and 5-minute Apgar scores, neonatal intensive care unit (NICU) admission, neonatal and perinatal death, and small for gestational age. Of the 1421 studies identified, 79 met the defined criteria; 56 studies were descriptive and 23 were comparative. Based on the descriptive studies, the preterm delivery rates for low-lying/marginal placenta, placenta previa, placenta accreta, vasa previa, and velamentous cord insertion were 26.9%, 43.5%, 57.7%, 81.9%, and 37.5%, respectively. Based on the comparative studies using controls, there was decreased pregnancy duration for every PIA; more specifically, there was an increased risk for preterm delivery in patients with placenta previa (risk ratio [RR], 5.32; 95% confidence interval [CI], 4.39-6.45), vasa previa (RR, 3.36; 95% CI, 2.76-4.09), and velamentous cord insertion (RR, 1.95; 95% CI, 1.67-2.28). Risks of NICU admissions (RR, 4.09; 95% CI, 2.80-5.97), neonatal death (RR, 5.44; 95% CI, 3.03-9.78), and perinatal death (RR, 3.01; 95% CI, 1.41-6.43) were higher with placenta previa. Perinatal risks were also higher in patients with vasa previa (perinatal death rate RR, 4.52; 95% CI, 2.77-7.39) and velamentous cord insertion (NICU admissions [RR, 1.76; 95% CI, 1.68-1.84], small for gestational age [RR, 1.69; 95% CI, 1.56-1.82], and perinatal death [RR, 2.15; 95% CI, 1.84-2.52]). In singleton gestations, there is a strong association between PIA and preterm delivery resulting in significant perinatal morbidity and mortality.

17-alpha-hydroxyprogesterone caproate for maintenance tocolysis: a systematic review and metaanalysis of randomized trials

We sought to evaluate the efficacy of maintenance tocolysis with 17-alpha-hydroxyprogesterone caproate (17P) compared to control (either placebo or no treatment) in singleton gestations with arrested preterm labor (PTL), in a metaanalysis of randomized trials. Electronic databases (MEDLINE, OVID, Scopus, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials) were searched from 1966 through July 2014. Key words included "progesterone," "tocolysis," "preterm labor," and "17-alpha-hydroxyprogesterone caproate." We performed a metaanalysis of randomized trials of singleton gestations with arrested PTL and treated with maintenance tocolysis with either 17P or control. Primary outcome was preterm birth (PTB) <37 weeks. This metaanalysis was performed following the Preferred Reporting Items for Systematic Reviews and Metaanalyses (PRISMA) statement. The protocol was registered with PROSPERO (registration no: CRD42014013473). Five randomized trials met inclusion criteria, including 426 women. Women with a singleton gestation who received 17P maintenance tocolysis for arrested PTL had a similar rate of PTB <37 weeks (42% vs 51%; relative risk [RR], 0.78; 95% confidence intervals [CI], 0.50-1.22) and PTB <34 weeks (25% vs 34%; RR, 0.60; 95% CI, 0.28-1.12) compared to controls. Women who received 17P had significantly later gestational age at delivery (mean difference, 2.28 weeks; 95% CI, 1.46-13.51), longer latency (mean difference, 8.36 days; 95% CI, 3.20-13.51), and higher birthweight (mean difference, 224.30 g; 95% CI, 70.81-377.74) as compared to controls. Other secondary outcomes including incidences of recurrent PTL, neonatal death, admission to neonatal intensive care unit, neonatal respiratory distress syndrome, bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis, and neonatal sepsis were similar in both groups. Maintenance tocolysis with 17P after arrested PTL is not associated with prevention of PTB compared to placebo or no treatment in a metaanalysis of the available randomized trials. As 17P for maintenance tocolysis is associated with a significant prolongation of pregnancy, and significantly higher birthweight, further research is suggested.

Metaanalysis of BRAF mutations and clinicopathologic characteristics in primary melanoma

BACKGROUND

BRAF mutations occur in some melanomas. We hypothesized that BRAF mutation rates may differ in melanomas found in Asian compared to white populations.

OBJECTIVE

We performed a metaanalysis of BRAF mutations and their associations with the clinicopathologic characteristics of primary melanoma (PM), with a subgroup analysis to compare Asian and white patients with PM.

METHODS

The PubMed, EMBASE, and Cochrane databases were searched up to November 2013. The incidence rates and odds ratios (ORs) of BRAF mutations were calculated using a fixed or random effects model.

RESULTS

BRAF mutation was associated with younger age (OR = 1.734; P < .001), trunk location (OR = 2.272; P < .001), non-chronically sun damaged skin (OR = 2.833; P < .001), superficial spreading melanoma (OR = 2.081; P < .001), and advanced melanoma stage (OR = 1.551; P = .003). The incidence of BRAF mutations in Asian patients with PM was half that of white patients with PM, but it was linked to the same clinicopathologic characteristics.

LIMITATIONS

Only a small number of studies have been conducted on Asian patients with PMs.

CONCLUSIONS

The BRAF mutation in PM was associated with age, anatomic site based on ultraviolet radiation exposure, histologic subtype, and advanced stage of melanoma. The clinicopathologic associations with BRAF mutations were similar in Asian and white patients with PM.

Association of atopic dermatitis with being overweight and obese: a systematic review and metaanalysis

BACKGROUND

Previous studies found conflicting results about whether atopic dermatitis (AD) is associated with overweight/obesity.

OBJECTIVE

We sought to examine the relationship between AD and overweight/obesity by performing a systematic review and metaanalysis.

METHODS

Observational studies of the relationship between AD and overweight/obesity were selected from PubMed, Embase, and the Cochrane Library. The quality of evidence was assessed using the Newcastle-Ottawa Scale. Fixed and random effects metaanalyses were performed to estimate pooled odds ratios (ORs). Sensitivity analyses were performed that compared results by location of study, study quality, and between studies in children and adults.

RESULTS

In total, 30 studies were included for review. Patients who were overweight (Cochrane-Mantel-Haenszel [CMH] OR, 1.27 [95% confidence interval {CI}: 1.19-1.36]; random effects OR, 1.23 [95% CI: 1.11-1.41]), obese (CMH OR, 1.68 [95% CI: 1.54-1.84]; random effects OR, 1.47 [95% CI: 1.21-1.79]), or overweight/obese (CMH OR, 1.42 [95% CI: 1.34-1.50]; random effects OR, 1.31 [95% CI: 1.16-1.48]) had higher odds of AD than normal weight patients. In sensitivity analyses, children who were overweight (random effects OR, 1.24 [95% CI: 1.08-1.43]), obese (random effects OR, 1.44 [95% CI: 1.12-1.86]), or overweight/obese (random effects OR, 1.32 [95% CI: 1.15-1.51]) and adults who were obese (random effects OR, 1.56 [95% CI: 1.24-1.95]) or overweight/obese (random effects OR, 1.29 [95% CI: 1.05-1.59]) had higher odds of AD. The association remained significant in North America and Asia but not Europe.

LIMITATIONS

Most studies were cross-sectional.

CONCLUSIONS

Overweight/obesity in North America and Asia is associated with an increased prevalence of AD.

Antibiotic prophylaxis for term or near-term premature rupture of membranes: metaanalysis of randomized trials

OBJECTIVE

The objective of the study was to evaluate the efficacy of antibiotic prophylaxis in women with term or near-term premature rupture of membranes.

STUDY DESIGN

Searches were performed in MEDLINE, OVID, Scopus, ClinicalTrials.gov, the PROSPERO International Prospective Register of Systematic Reviews, EMBASE, ScienceDirect.com, MEDSCAPE, and the Cochrane Central Register of Controlled Trials with the use of a combination of key words and text words related to antibiotics, premature rupture of membranes, term, and trials from inception of each database to September 2014. We included all randomized trials of singleton gestations with premature rupture of membranes at 36 weeks or more, who were randomized to antibiotic prophylaxis or control (either placebo or no treatment). The primary outcomes included maternal chorioamnionitis and neonatal sepsis. A subgroup analysis on studies with latency more than 12 hours was planned. Before data extraction, the review was registered with the PROSPERO International Prospective Register of Systematic Reviews (registration number CRD42014013928). The metaanalysis was performed following the Preferred Reporting Item for Systematic Reviews and Meta-analyses statement.

RESULTS

Women who received antibiotics had the same rate of chorioamnionitis (2.7% vs 3.7%; relative risk [RR], 0.73, 95% confidence interval [CI], 0.48-1.12), endometritis (0.4% vs 0.9%; RR, 0.44, 95% CI, 0.18-1.10), maternal infection (3.1% vs 4.6%; RR, 0.48, 95% CI, 0.19-1.21), and neonatal sepsis (1.0% vs 1.4%; RR, 0.69, 95% CI, 0.34-1.39). In the planned subgroup analysis, women with latency longer than 12 hours, who received antibiotics, had a lower rate of chorioamnionitis (2.9% vs 6.1%; RR, 0.49, 95% CI, 0.27-0.91) and endometritis (0% vs 2.2%; RR, 0.12, 95% CI, 0.02-0.62) compared with the control group.

CONCLUSION

Antibiotic prophylaxis for term or near-term premature rupture of membranes is not associated with any benefits in either maternal or neonatal outcomes. In women with latency longer than 12 hours, prophylactic antibiotics are associated with significantly lower rates of chorioamnionitis by 51% and endometritis by 88%.

Deaths attributable to carbapenem-resistant Enterobacteriaceae infections

In 7 studies, rates ranged from 26% to 44%; in 2 studies, rates were −3% and −4%, respectively.

We evaluated the number of deaths attributable to carbapenem-resistant Enterobacteriaceae by using studies from around the world published before April 9, 2012. Attributable death was defined as the difference in all-cause deaths between patients with carbapenem-resistant infections and those with carbapenem-susceptible infections. Online databases were searched, and data were qualitatively synthesized and pooled in a metaanalysis. Nine studies met inclusion criteria: 6 retrospective case–control studies, 2 retrospective cohort studies, and 1 prospective cohort study. Klebsiella pneumoniae was the causative pathogen in 8 studies; bacteremia was the only infection in 5 studies. We calculated that 26%–44% of deaths in 7 studies were attributable to carbapenem resistance, and in 2 studies, which included bacteremia and other infections, −3% and −4% of deaths were attributable to carbapenem resistance. Pooled outcomes showed that the number of deaths was significantly higher in patients with carbapenem-resistant infections and that the number of deaths attributable to carbapenem resistance is considerable.

[Helicobacter pylori -- 2014]

The author reviews the main achievements in Helicobacter pylori research in the past 2 years. Of the more than 1000 microRNAs described thus far, sets of over- and underexpressed samples were identified that are associated with either gastric cancer or precancerous lesions, and some of them could be either markers or therapeutic targets in the near future. Meta-analyses involved 95 new publications: the association between infection and oesophageal, colorectal, pancreatic and liver carcinomas is supported by the increased odds ratios, but the results do not reach the strength seen in gastric carcinoma. Epstein-Barr virus is an emerging pathogen: 10% of gastric cancers are virus-associated; the prevalence of the virus in normal mucosa, chronic gastritis and peptic ulcer are currently being studied. Current Helicobacter pylori eradication regimens frequently achieve suboptimal results: a few optimisation methods are presented, although not all are supported by the meta-analyses. In 2013, the European Helicobacter Study Group proposed the development of a pan-European registry; data from 5792 patients registered so far indicated that many therapeutic regimens resulted in a low eradication rate. In 2013, the Healthy Stomach Initiative was started with the aim of supporting and disseminating research performed in the field of healthy and diseased stomachs.

Percutaneous vertebroplasty and percutaneous balloon kyphoplasty for osteoporotic vertebral compression fracture: A metaanalysis

BACKGROUND

Osteoporotic vertebral compression fracture (OVCF) is the most common complication of osteoporosis, however, debate persists over which procedure of percutaneous vertebroplasty (PVP) or balloon kyphoplasty (BKP) is a better treatment. We performed a metaanalysis of prospective, randomized controlled and clinical controlled trials of PVP and BKP to determine the efficacy and safety for the treatment of OVCFs to reach a relatively conclusive answer.

MATERIALS AND METHODS

We searched computerized databases comparing efficacy and safety of PVP and BKP in osteoporotic vertebral compression fractures. These reports included pain relief, functional capacity (Oswestry disability index [ODI] score), anterior vertebral body height (AVBH), kyphotic angle and complications (i.e. cement leakage, incident fractures). Studies were assessed for methodological bias and potential reasons for heterogeneity were explored.

RESULTS

As of March 15, 2013, a PubMed search resulted in 761 articles, of which eleven studies encompassing 789 patients, met the inclusion criteria. The average length of followup is 17 months and 4.6% patients were lost to followup. Results of metaanalysis indicated that BKP is more effective for short term pain relief. In addition, BKP is more effective to restore the AVBH (anterior vertebral body height), ODI and kyphotic angle of OVCFs. Moreover, BKP need more polymethylmethacrylate amount.

CONCLUSIONS

In terms of better effectiveness of BKP procedure, we believe BKP to be superior over PVP for the treatment of osteoporotic VCFs.

Deciding whether follow-up studies have replicated findings in a preliminary large-scale omics study

We propose a formal method to declare that findings from a primary study have been replicated in a follow-up study. Our proposal is appropriate for primary studies that involve large-scale searches for rare true positives (i.e., needles in a haystack). Our proposal assigns an r value to each finding; this is the lowest false discovery rate at which the finding can be called replicated. Examples are given and software is available.

Association between maternal body mass index and congenital heart defects in offspring: a systematic review

The aim of this study was to investigate the relationship between maternal body mass index and all congenital heart defects (CHDs) combined and 11 individual defects. PubMed, ELSEVIER ScienceDirect, and Springer Link (up to February 2013) were searched, and the reference list of retrieved articles was reviewed. Three authors independently extracted the data. The systematic review included 24 studies, 14 of which were included in a metaanalysis. Statistical software was used to perform all statistical analyses. Fixed-effects or random-effects model was used to pool the results of individual study (expressed as odds ratios [ORs] with 95% confidence intervals [CIs]). A dose-response effect was observed between overweight, moderate obesity, and severe obesity and a pregnancy with any CHD (the pooled ORs: OR, 1.08 [95% CI, 1.02-1.15]; OR, 1.15 [95% CI, 1.11-1.20]; and OR, 1.39 [95% CI, 1.31-1.47], respectively) as well as some individual defects such as hypoplastic left heart syndrome, pulmonary valve stenosis, and outflow tract defects. When we excluded mothers with diabetes mellitus, the pooled ORs for all CHDs combined were 1.12 (95% CI, 1.04-1.20) and 1.38 (95% CI, 1.20-1.59) for moderately obese and severely obese, respectively. The highest increased risk was severely obese mothers for tetralogy of Fallot (OR, 1.94; 95% CI, 1.49-2.51). Being underweight did not increase the risk of any of the aforementioned CHDs but did increase the risk of aortic valve stenosis (OR, 1.47; 95% CI, 1.01-2.15]). The results of our study showed that increasing maternal body mass index was associated with an increasing risk of CHDs; severe obesity was an even greater risk factor for the development of CHDs.

Increasing prevalence of hypertension among patients with thoracic aorta dissection: trends over eight decades--a structured meta-analysis

BACKGROUND

This structured metaanalysis focused on determining the relationship between hypertension (HTN) and thoracic aortic dissection (TAD).

METHODS

Electronic searches were conducted using the MedLine database, for the period 1946 through May 2013, and manual searches from reference lists. Demographic data, patient diagnosis, and HTN prevalence were extracted from each study. Data were analyzed using weighted averages, metaanalysis, analysis of variance, trend analysis, and multivariate analysis.

RESULTS

A total of 8,086 cases of TAD from 75 studies over eight decades were assessed. Overall prevalence of HTN in TAD was 66.7% ± 17.5%. An increase of approximately 5.6% in HTN prevalence in TAD cases occurred in every decade. Prevalence of HTN in type A dissections steadily increased, with an overall prevalence of 64.8% ± 21.3%, while in type B dissections, prevalence abruptly increased from 1950 to 1970 and remained constant thereafter, with an overall prevalence of 78.7% ± 8.6%. Trend analysis demonstrated significant (P < 0.001) and linear increasing trends for the prevalence of HTN and age at presentation. Multivariate analysis demonstrated that a history of HTN was significantly (P < 0.001) associated with increasing trends of over time, which was independent of the relationship between age and TAD.

CONCLUSIONS

The proportion of TAD patients with HTN has been increasing over eight decades. Age at presentation of TAD has also been incrementally increasing, but the increase in HTN was independent of age in multivariate analysis. The trend for increasing HTN prevalence was more evident in type A TAD. These data highlight a need to focus on HTN management in patients with thoracic aortic aneurysm.

Pegylated liposomal doxorubicin in the management of ovarian cancer: a systematic review and metaanalysis of randomized trials

Ovarian cancer is the leading cause of death among gynecological tumors. Carboplatin/paclitaxel represents the cornerstone of front-line treatment. Instead, there is no consensus for management of recurrent/progressive disease, in which pegylated liposomal doxorubicin (PLD) ± carboplatin is widely used. We performed a systematic review and metaanalysis to evaluate impact of PLD-based compared with no-PLD-based regimens in the ovarian cancer treatment. Data were extracted from randomized trials comparing PLD-based treatment to any other regimens in the January 2000-January 2013 time-frame. Study end-points were overall survival (OS), progression free survival (PFS), response rate (RR), CA125 response, and toxicity. Hazard ratios (HRs) of OS and PFS, with 95% CI, odds ratios (ORs) of RR and risk ratios of CA125 response and grade 3-4 toxicity, were extracted. Data were pooled using fixed and random effect models for selected endpoints. Fourteen randomized trials for a total of 5760 patients were selected and included for the final analysis, which showed no OS differences for PLD-based compared with other regimens (pooled HR: 0.94; 95% CI: 0.88-1.02; P = 0.132) and a significant PFS benefit of PLD-based schedule (HR: 0.91; 95% CI: 0.86-0.96; P = 0.001), particularly in second-line (HR: 0.85; 95% CI: 0.75-0.91) and in platinum-sensitive (HR: 0.83; 95% CI: 0.74-0.94) subgroups. This work confirmed the peculiar tolerability profile of this drug, moreover no difference was observed for common hematological toxicities and for RR, CA125 response. PLD-containing regimens do not improve OS when compared with any other schedule in all phases of disease. A marginal PFS advantage is observed only in platinum-sensitive setting and second-line treatment.

Air pollution and nonmalignant respiratory mortality in 16 cohorts within the ESCAPE project

RATIONALE

Prospective cohort studies have shown that chronic exposure to particulate matter and traffic-related air pollution is associated with reduced survival. However, the effects on nonmalignant respiratory mortality are less studied, and the data reported are less consistent.

OBJECTIVES

We have investigated the relationship of long-term exposure to air pollution and nonmalignant respiratory mortality in 16 cohorts with individual level data within the multicenter European Study of Cohorts for Air Pollution Effects (ESCAPE).

METHODS

Data from 16 ongoing cohort studies from Europe were used. The total number of subjects was 307,553. There were 1,559 respiratory deaths during follow-up.

MEASUREMENTS AND MAIN RESULTS

Air pollution exposure was estimated by land use regression models at the baseline residential addresses of study participants and traffic-proximity variables were derived from geographical databases following a standardized procedure within the ESCAPE study. Cohort-specific hazard ratios obtained by Cox proportional hazard models from standardized individual cohort analyses were combined using metaanalyses. We found no significant associations between air pollution exposure and nonmalignant respiratory mortality. Most hazard ratios were slightly below unity, with the exception of the traffic-proximity indicators.

CONCLUSIONS

In this study of 16 cohorts, there was no association between air pollution exposure and nonmalignant respiratory mortality.

Study design and clinical evidence in mRCC: can we save axitinib as a first-line therapy?

Tyrosine kinase inhibitors are de facto the most commonly used targeted therapies for upfront treatment of metastatic renal cell carcinoma (mRCC). After the first era in which targeted agents were compared with placebo and interferon-α, a new phase has started in recent years characterized by head-to-head trials comparing targeted agents in superiority or non-inferiority trials. Recently, the results a head-to-head phase III trial comparing axitinib to sorafenib as upfront therapy in patients affected by mRCC have been reported. We discuss several critical aspects of this study and the results of our metaanalysis on the activity of axitinib over sorafenib in a larger population with the intent to confirm the superiority of axitinib. Despite this, the definition of primary endpoint remains a central factor in determining the final results of a trial.

Maternal coffee consumption during pregnancy and risk of childhood acute leukemia: a metaanalysis

OBJECTIVE

This study was undertaken to explore the association between maternal coffee consumption during pregnancy and childhood acute leukemia (AL).

STUDY DESIGN

The PubMed database was used to search studies up to May 5, 2013, and the lists of references of retrieved articles were also screened to identify additional relevant studies. Studies were included if they reported the odds ratio and corresponding 95% confidence interval (CI) of childhood AL, including childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML), with respect to maternal coffee consumption during pregnancy.

RESULTS

Compared with non/lowest drinkers, the combined odds ratio regarding the relationship of maternal coffee consumption during pregnancy and childhood AL was 1.22 (95% CI, 1.04-1.43) for ever drinkers, 1.16 (95% CI, 1.00-1.34) for low to moderate-level drinkers, and 1.72 (95% CI, 1.37-2.16) for high-level drinkers. When analysis was conducted by subtypes of childhood AL, maternal coffee consumption (high-level drinkers vs non/lowest drinkers) was statistically significantly associated with childhood ALL (1.65; 95% CI, 1.28-2.12) and childhood AML (1.58; 95% CI, 1.20-2.08). We observed the linear dose-response relationship of coffee consumption and childhood AL (P for nonlinearity = .68), including childhood ALL and childhood AML; with increased coffee consumption, the risk of childhood AL increased.

CONCLUSION

The findings of the metaanalysis suggest that maternal coffee consumption during pregnancy may increase the risk of childhood AL. Because of limited studies, further prospective studies are urgently needed to explore the adverse effect of coffee consumption on childhood AL.

Laparoendoscopic single-site versus conventional laparoscopic gynecologic surgery: a metaanalysis of randomized controlled trials

OBJECTIVE

To assess the current evidence regarding the efficiency, safety, and potential advantages of laparoendoscopic single-site surgery (LESS) for treating gynecologic diseases.

STUDY DESIGN

We comprehensively searched PubMed, Embase, and the Cochrane Library from their inception to December 2012. Two authors screened out duplicates and independently reviewed eligibility of each study. We included randomized controlled trials comparing LESS with conventional laparoscopy (CL) for treating gynecologic diseases. The primary outcomes were perioperative complication rate, conversion rate, postoperative pain, and cosmetic satisfaction.

RESULTS

We included 6 randomized controlled trials with 439 participants in the final analysis. There were no significant differences between LESS and CL in terms of perioperative complication rate (15.5% and 14.3%; risk ratio, 1.11; 95% confidence interval [CI], 0.74-1.67; P = .61), conversion rate (3.8% and 1.1%; risk ratio, 2.75; 95% CI, 0.73-10.33; P = .13), postoperative pain (weighted mean difference [WMD], -0.22; 95% CI, -1.29 to 0.85; P = .68), analgesic requirement (WMD, 0.41; 95% CI, -1.69 to 2.51; P = .70), and cosmetic satisfaction (WMD, 0.19; 95% CI, -0.30 to 0.68; P = .46). There were also no differences in terms of operative time (P = .65), hemoglobin change (P = .23), time to first flatus (P = .17), and length of hospital stay (P = .99) between both techniques.

CONCLUSION

This metaanalysis provides evidence that LESS is comparable in the efficacy and safety, but does not offer potential advantage such as better cosmesis and lesser pain compared with CL for treating gynecologic diseases.

Primary small cell carcinoma of the esophagus: patient data metaanalysis and review of the literature

We analysed the typical features of primary small cell carcinoma of the esophagus (SCCE) with emphasis on occurrence, behaviour, outcome and treatment options. This metaanalysis was aimed at collecting and analyzing information from international studies about handling this disease. This seems necessary due to the rarity of this disease. Studies were acquired from electronic databases and reference lists. We finally analysed 313 patient cases from the literature with oesophageal SCC. A data extraction was accomplished referring to 13 evaluable features that are described in the "methods", whereof 7 were analyzed with univariate and multivariate tests. Three hundred thirteen cases were analyzed, 109 patients (35%) had limited stage (LS), whereas 167 (54%) had extensive stage (ES). There is no information about the remaining 35 patients concerning the stage. Univariate and multivariate analysis showed only age (<50 years vs. >50 years, HR 1.024; 95% CI 1.000-1.041, P<0.0001) and disease stage (LS vs. ES, HR 4.884; 95% CI 2.572-9.27, P<0.0001) as significant prognostic factors. There also was a statistically significant difference in survival between those patients who received therapy compared to those who only received best supportive care (11.6 months vs. 0.8 months, HR 0.093, CI 95% 0.053-0.16, P<0.001). In this first multivariate analysis for SCCE we show that SCCE is an aggressive type of tumour with a shorter survival rate compared to its counterpart from the lung. It is demonstrated that only disease stage (limited vs. extensive stage), age (<50 years vs. >50 years) and therapy are independent significant predictors of prognosis.

Non-hepatic tumors change the activity of genes encoding copper trafficking proteins in the liver

To assess the statistical relationship between tumor growth and copper metabolism, we performed a metaanalysis of studies in which patients with neoplasms were characterized according to any of the copper status indexes (atomic copper serum concentration, serum oxidase activity, ceruloplasmin protein content). Our metaanalysis shows that in the majority of cases (more than 3100 patients), tumor growth positively correlates with the copper status indexes. Nude athymic CD-1 nu/nu mice with subcutaneous tumors of human origin, C57Bl/6J mice with murine melanoma and Apc(Min) mice with spontaneously developing adenomas throughout the intestinal tract were studied to experimentally determine the relationship between tumor progression, liver copper metabolism, and copper status indexes. We showed that the copper status indexes increased significantly during tumor growth. In the liver tissue of tumor-bearing mice, ceruloplasmin gene expression, as well as the expression of genes related to ceruloplasmin metallation (CTR1 and ATP7B), increased significantly. Moreover, the presence of an mRNA splice variant encoding a form of ceruloplasmin anchored to the plasma membrane by glycosylphosphatidyl inositol, which is atypical for hepatocytes, was also detected. The ATP7A copper transporter gene, which is normally expressed in the liver only during embryonic copper metabolism, was also activated. Depletion of holo-ceruloplasmin resulted in retardation of human HCT116 colon carcinoma cell growth in nude mice and induced DNA fragmentation in tumor cells. In addition, the concentration of cytochrome c increased significantly in the cytosol, while decreasing in the mitochondria. We discuss a possible trans-effect of developing tumors on copper metabolism in the liver.

The role of biologic agents in damage progression in rheumatoid arthritis: indirect comparison of data coming from randomized clinical trials

OBJECTIVES

All biologic agents approved for the treatment of rheumatoid arthritis (RA) have been tested versus methotrexate (MTX) for efficacy on damage progression in several randomized clinical trials (RCTs), but direct head-to-head comparisons have never been conducted. The purpose of this investigation is to analyse data coming from main RA RCTs and to perform an indirect comparison.

METHODS

A systematic review of literature from 1988 to 2011 was conducted. Only randomized, double-blind, controlled, comparative trials, with evaluation of radiographic progression were included. The radiographic score was standardized and mean difference in the percentage of the annual radiographic progression rate was used as the effect measure. Heterogeneity between studies was estimated by I(2) test. For each trial, the effect was plotted according to its standard error in a funnel plot.

RESULTS

Of 44 potentially relevant trials, 12 RCTs were included in the study. In order to optimize RCTs comparison, studies were stratified in early and late RA group. Main population characteristics were similar in both early and late RA groups, whereas the standardized baseline radiographic score value significantly differs among trials in both early (range 2.7-21.9) and late (range 23.46-75) RA groups. The standardized annual estimated progression is similar across the late RA group. Strong evidence of heterogeneity (I(2) = 97%, p = 0.00001) but no asymmetry of the funnel plot was observed in the early RA group. Total mean difference was -16.28 (95% confidence interval [CI] -24.42 to -8.14). For the late RA group a random model was used (I(2) = 99%, p = 0.00001) and a total mean difference of -39.25 (95% CI -53.77 to -24.73) was found.

CONCLUSIONS

All biologic agents provide a favourable effect on disease progression both in early and late RA. The significant heterogeneity among various RCTs did not allow an effective comparison of the performance of biologic agents in each study.

Vaginal bleeding in early pregnancy and preterm birth: systemic review and analysis of heterogeneity

OBJECTIVE

To systemically review published studies of vaginal bleeding and the risk of preterm birth (PTB) and explore sources of heterogeneity between them.

METHODS

The literature was searched for peer-reviewed articles from 1980 to 2009 in which the primary analysis was the risk of PTB among low-risk subjects with and without bleeding. Heterogeneity was assessed through I(2) statistics, and sources of heterogeneity were explored through subgroup analyses and meta-regression.

RESULTS

218 studies were initially identified, 64 reviewed and 23 included. The pooled Odds Ratio for PTB was 1.74, though significant heterogeneity was present (I(2)  =  49.7%). Meta-regression demonstrated a significant association between a study's incidence of bleeding and quality assessment and subsequent odds ratio, such that studies with a lower quality assessment or lower incidence of bleeding demonstrated an increased odds of PTB.

CONCLUSIONS

Bleeding in early pregnancy is associated with an increased risk of PTB; however, excessive heterogeneity exists among published studies. The heterogeneity arises in part from differences in the reported incidence of bleeding within study populations. Presumably studies that identify bleeding in a larger percentage of subjects consequently dilute the magnitude of the risk.

Uses and misuses of the STROBE statement: bibliographic study

Objectives Appropriate reporting is central to the application of findings from research to clinical practice. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations consist of a checklist of 22 items that provide guidance on the reporting of cohort, case-control and cross-sectional studies, in order to facilitate critical appraisal and interpretation of results. STROBE was published in October 2007 in several journals including The Lancet, BMJ, Annals of Internal Medicine and PLoS Medicine. Within the framework of the revision of the STROBE recommendations, the authors examined the context and circumstances in which the STROBE statement was used in the past. Design The authors searched the Web of Science database in August 2010 for articles which cited STROBE and examined a random sample of 100 articles using a standardised, piloted data extraction form. The use of STROBE in observational studies and systematic reviews (including meta-analyses) was classified as appropriate or inappropriate. The use of STROBE to guide the reporting of observational studies was considered appropriate. Inappropriate uses included the use of STROBE as a tool to assess the methodological quality of studies or as a guideline on how to design and conduct studies. Results The authors identified 640 articles that cited STROBE. In the random sample of 100 articles, about half were observational studies (32%) or systematic reviews (19%). Comments, editorials and letters accounted for 15%, methodological articles for 8%, and recommendations and narrative reviews for 26% of articles. Of the 32 observational studies, 26 (81%) made appropriate use of STROBE, and three uses (10%) were considered inappropriate. Among 19 systematic reviews, 10 (53%) used STROBE inappropriately as a tool to assess study quality. Conclusions The STROBE reporting recommendations are frequently used inappropriately in systematic reviews and meta-analyses as an instrument to assess the methodological quality of observational studies.

Transvaginal sonographic cervical length for the prediction of spontaneous preterm birth in twin pregnancies: a systematic review and metaanalysis

OBJECTIVE

To assess the accuracy of transvaginal sonographic cervical length (CL) in predicting spontaneous preterm birth in women with twin pregnancies.

STUDY DESIGN

Systematic review and metaanalysis of predictive test accuracy.

RESULTS

Twenty-one studies (16 in asymptomatic women and 5 in symptomatic women) with a total of 3523 women met the inclusion criteria. Among asymptomatic women, a CL

CONCLUSION

Transvaginal sonographic CL at 20-24 weeks' gestation is a good predictor of spontaneous preterm birth in asymptomatic women with twin pregnancies.

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Key Words

• cervical length
• preterm birth
• prediction
• metaanalysis
• systematic review

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MESH Headings

• Cervix Uteri/anatomy & histology
• Cervix Uteri/diagnostic imaging
• Female
• Gestational Age
• Humans
• Incidence
• Infant, Newborn
• Predictive Value of Tests
• Pregnancy
• Pregnancy Outcome
• Pregnancy, Multiple
• Premature Birth/diagnostic imaging
• Premature Birth/epidemiology
• Risk Assessment
• Twins
• Ultrasonography, Prenatal

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Grants

• ZIA HD002401 Intramural NIH HHS
• ZIA HD002401-18 Intramural NIH HHS

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Assessing the relationship between antigenicity and immunogenicity of human rabies vaccines when administered by intradermal route: results of a metaanalysis

The metadata of 10 published studies and 3 vaccine trial reports comprising of 19 vaccine cohorts from four countries conducted over a period of 23 years (1986 - 2009) was used for metaanalysis. The vaccines studied were purified chick embryo cell vaccine (Rabipur, India & Germany), purified vero cell rabies vaccine (Verorab, France; Indirab, India) & human diploid cell vaccine (MIRV, France).The potency of these vaccines varied from 0.55 IU to 2.32 IU per intradermal dose of 0.1 ml per site. The vaccines were administered to 1,011 subjects comprising of 19 cohorts and using five different ID regimens. The immunogenicity was measured by assays of rabies virus neutralizing antibody (RVNA) titres using rapid fluorescent focus inhibition test (RFFIT) [15 cohorts] and mouse neutralization test (MNT) [4 cohorts]. The statistical analysis of the data was done by Karl Pearson's correlation coefficient to measure the relationship between antigenicity and immunogenicity. It was revealed that, there was no significant linear relationship between antigenicity and immunogenicity of rabies vaccines when administered by intradermal route. (p> 0.230 and p>0.568).

The extended language network: a meta-analysis of neuroimaging studies on text comprehension

Language processing in context requires more than merely comprehending words and sentences. Important subprocesses are inferences for bridging successive utterances, the use of background knowledge and discourse context, and pragmatic interpretations. The functional neuroanatomy of these text comprehension processes has only recently been investigated. Although there is evidence for right-hemisphere contributions, reviews have implicated the left lateral prefrontal cortex, left temporal regions beyond Wernicke's area, and the left dorso-medial prefrontal cortex (dmPFC) for text comprehension. To objectively confirm this extended language network and to evaluate the respective contribution of right hemisphere regions, meta-analyses of 23 neuroimaging studies are reported here. The analyses used replicator dynamics based on activation likelihood estimates. Independent of the baseline, the anterior temporal lobes (aTL) were active bilaterally. In addition, processing of coherent compared with incoherent text engaged the dmPFC and the posterior cingulate cortex. Right hemisphere activations were seen most notably in the analysis of contrasts testing specific subprocesses, such as metaphor comprehension. These results suggest task dependent contributions for the lateral PFC and the right hemisphere. Most importantly, they confirm the role of the aTL and the fronto-medial cortex for language processing in context.

Ecological rules governing helminth-microparasite coinfection

Coinfection of a host by multiple parasite species has important epidemiological and clinical implications. However, the direction and magnitude of effects vary considerably among systems, and, until now, there has been no general framework within which to explain this variation. Community ecology has great potential for application to such problems in biomedicine. Here, metaanalysis of data from 54 experiments on laboratory mice reveals that basic ecological rules govern the outcome of coinfection across a broad spectrum of parasite taxa. Specifically, resource-based ("bottom-up") and predator-based ("top-down") control mechanisms combined to determine microparasite population size in helminth-coinfected hosts. Coinfection imposed bottom-up control (resulting in decreased microparasite density) when a helminth that causes anemia was paired with a microparasite species that requires host red blood cells. At the same time, coinfection impaired top-down control of microparasites by the immune system: the greater the helminth-induced suppression of the inflammatory cytokine interferon (IFN)-gamma, the greater the increase in microparasite density. These results suggest that microparasite population growth will be most explosive when underlying helminths do not impose resource limitations but do strongly modulate IFN-gamma responses. Surprisingly simple rules and an ecological framework within which to analyze biomedical data thus emerge from analysis of this dataset. Through such an interdisciplinary lens, predicting the outcome of coinfection may become tractable.

Consumer versus resource control of producer diversity depends on ecosystem type and producer community structure

Consumer and resource control of diversity in plant communities have long been treated as alternative hypotheses. However, experimental and theoretical evidence suggests that herbivores and nutrient resources interactively regulate the number and relative abundance of coexisting plant species. Experiments have yielded divergent and often contradictory responses within and among ecosystems, and no effort has to date reconciled this empirical variation within a general framework. Using data from 274 experiments from marine, freshwater, and terrestrial ecosystems, we present a cross-system analysis of producer diversity responses to local manipulations of resource supply and/or herbivory. Effects of herbivory and fertilization on producer richness differed substantially between systems: (i) herbivores reduced species richness in freshwater but tended to increase richness in terrestrial systems; (ii) fertilization increased richness in freshwater systems but reduced richness on land. Fertilization consistently reduced evenness, whereas herbivores increased evenness only in marine and terrestrial ecosystems. Producer community evenness and ecosystem productivity mediated fertilization and herbivore effects on diversity across ecosystems. Herbivores increased producer richness in more productive habitats and in producer assemblages with low evenness. These same assemblages also showed the strongest reduction in richness with fertilization, whereas fertilization increased (and herbivory decreased) richness in producer assemblages with high evenness. Our study indicates that system productivity and producer evenness determine the direction and magnitude of top-down and bottom-up control of diversity and may reconcile divergent empirical results within and among ecosystems.

Functional- and abundance-based mechanisms explain diversity loss due to N fertilization

Human activities have increased N availability dramatically in terrestrial and aquatic ecosystems. Extensive research demonstrates that local plant species diversity generally declines in response to nutrient enrichment, yet the mechanisms for this decline remain unclear. Based on an analysis of >900 species responses from 34 N-fertilization experiments across nine terrestrial ecosystems in North America, we show that both trait-neutral and trait-based mechanisms operate simultaneously to influence diversity loss as production increases. Rare species were often lost because of soil fertilization, randomly with respect to traits. The risk of species loss due to fertilization ranged from >60% for the rarest species to 10% for the most abundant species. Perennials, species with N-fixing symbionts, and those of native origin also experienced increased risk of local extinction after fertilization, regardless of their initial abundance. Whereas abundance was consistently important across all systems, functional mechanisms were often system-dependent. As N availability continues to increase globally, management that focuses on locally susceptible functional groups and generally susceptible rare species will be essential to maintain biodiversity.

Reliability of telepathology for frozen section service

One of the most promising applications of telepathology (pathology at a distance by electronic transmission of images in pathology) is frozen section diagnosis, especially because by means of this tool operations requiring an intraoperative histopathological diagnosis are feasible at hospitals without a pathologist on-site. For the introduction of this diagnostic tool into pathologist's daily practice the evidence of its diagnostic accuracy comparable to that of the conventional frozen section diagnosis is crucial. For this purpose the literature on the diagnostic accuracy of telepathological frozen section diagnosis was reviewed. In a metaanalysis these studies and reports, in which a total of more than 1290 cases had been examined, showed a slightly lower overall diagnostic accuracy (of the telepathological frozen section diagnosis) of about 0.91 than the conventional frozen section diagnosis with an average accuracy of about 0.98 found in an analysis of several studies (on frozen section diagnosis of different organs). This difference is at least predominantly caused by a higher rate of deferred and false negative frozen section diagnoses in the telepathological method, while the specificity of both methods, each more than 0.99 was not significantly different. In conclusion, the introduction of a telepathological frozen section diagnosis for hospitals without an acceptable access to a pathologist is justifiable already at the current state of the technological development especially when considering the advantages (time saving, reduction in costs) compared to the alternative of surgical interventions without access to an intraoperative diagnosis.

B-SPID: an object-relational database architecture to store, retrieve, and manipulate neuroimaging data

We propose a hardware and software architecture to respond to crucial problems in the neuroimaging field: storage, retrieval, and processing of large datasets. The B-SPID project, here discussed, concerns the processing of neuroimages and attached components stored in an object-relational multimedia database management system (DBMS). Advanced bioinformation concepts are exploited in this project such as large scale data storage, high level graphical user interfaces and 3D graphical processing and display of data. Our database implementation is based on standard programming components, runs on several UNIX platforms and is written to be evolutive. Queries on this database are designed to obtain and display from neuroimaging data several types of results (pictures, text, or 3D graphical shapes) on heterogeneous systems.