-
Environmental Science and Pollution... Aug 2022Congenital heart defects (CHDs) are one of the major causes of death in infants and young children, and heavy metal exposure during pregnancy is one of the possible risk... (Meta-Analysis)
Meta-Analysis Review
Congenital heart defects (CHDs) are one of the major causes of death in infants and young children, and heavy metal exposure during pregnancy is one of the possible risk factors. However, the effect of heavy metal exposure on CHDs is still controversial. We searched English (PubMed, Web of Science) and Chinese (CNKI and WanFang database) databases for relevant articles. The summarized effect sizes and 95% confidence intervals (CIs) were calculated by pooling estimates using the random-effects model. Egger's test was used to estimate publication bias. Heterogeneity among studies was indicated by p-values and I. Finally, we conducted subgroup analyses to elucidate the causes of heterogeneity. Thirteen studies were included in this meta-analysis. A positive association between maternal exposure to heavy metals and CHDs was found. Pooling odds ratios (ORs) for arsenic, cadmium, mercury, and lead were 2.12, 1.30, 1.22, and 2.30, respectively for total CHDs. Regarding CHD subtypes, arsenic was associated with an increased risk of septal defects (OR: 1.82), barium with left ventricular outflow tract obstruction (LVOTO) (OR: 1.15) and septal defects (OR: 1.21), and lead with conotruncal defects (OR: 2.34) and LVOTO (OR: 1.93). A heterogeneous relationship was found between studies using different methods of measurement, which were mainly due to differences in actual exposure levels to heavy metals. This meta-analysis suggests significant associations between arsenic, cadmium, mercury, and lead exposure during pregnancy and an increased risk of specific CHDs in offspring. These findings underscore the importance of heavy metal exposure during pregnancy in the risk of CHDs in offspring.
Topics: Arsenic; Cadmium; Child; Child, Preschool; Female; Heart Defects, Congenital; Humans; Maternal Exposure; Mercury; Pregnancy; Risk Factors
PubMed: 35668266
DOI: 10.1007/s11356-022-21071-7 -
Environmental Pollution (Barking, Essex... Mar 2024Exposure to toxic metals is a global public health threat. Among other adverse effects, exposure to the heavy metal cadmium has been associated with greater risk of... (Meta-Analysis)
Meta-Analysis Review
Exposure to toxic metals is a global public health threat. Among other adverse effects, exposure to the heavy metal cadmium has been associated with greater risk of cardiovascular disease (CVD). Nonetheless, the shape of the association between cadmium exposure and CVD risk is not clear. This systematic review summarizes data on the association between cadmium exposure and risk of CVD using a dose-response approach. We carried out a literature search in PubMed, Web of Science, and Embase from inception to December 30, 2023. Inclusion criteria were: studies on adult populations, assessment of cadmium exposure, risk of overall CVD and main CVD subgroups as endpoints, and observational study design (cohort, cross-sectional, or case-control). We retrieved 26 eligible studies published during 2005-2023, measuring cadmium exposure mainly in urine and whole blood. In a dose-response meta-analysis using the one-stage method within a random-effects model, we observed a positive association between cadmium exposure and risk of overall CVD. When using whole blood cadmium as a biomarker, the association with overall CVD risk was linear, yielding a risk ratio (RR) of 2.58 (95 % confidence interval-CI 1.78-3.74) at 1 μg/L. When using urinary cadmium as a biomarker, the association was linear until 0.5 μg/g creatinine (RR = 2.79, 95 % CI 1.26-6.16), after which risk plateaued. We found similar patterns of association of cadmium exposure with overall CVD mortality and risks of heart failure, coronary heart disease, and overall stroke, whereas for ischemic stroke there was a positive association with mortality only. Overall, our results suggest that cadmium exposure, whether measured in urine or whole blood, is associated with increased CVD risk, further highlighting the importance of reducing environmental pollution from this heavy metal.
Topics: Adult; Humans; Cardiovascular Diseases; Cadmium; Cross-Sectional Studies; Metals, Heavy; Biomarkers; Observational Studies as Topic
PubMed: 38295933
DOI: 10.1016/j.envpol.2024.123462 -
European Journal of Surgical Oncology :... Sep 2016Preoperative biliary drainage (PBD) with stenting increases complications compared with surgery without PBD. Metallic stents are considered superior to plastic stents... (Comparative Study)
Comparative Study Meta-Analysis Review
BACKGROUND
Preoperative biliary drainage (PBD) with stenting increases complications compared with surgery without PBD. Metallic stents are considered superior to plastic stents when considering stent-related complications. Aim of the present systematic review and meta-analysis is to compare the rate of endoscopic re-intervention before surgery and postoperative outcomes of metal versus plastic stents in patients with resectable periampullary or pancreatic head neoplasms.
METHODS
We conducted a bibliographic research using the National Library of Medicine's PubMed database, including both randomized controlled trials (RCTs) and non-RCTs. Quantitative synthesis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Statistical heterogeneity was assessed using the I(2) tests.
RESULTS
One RCT and four non-RCTs were selected, including 704 patients. Of these, 202 patients (29.5%) were treated with metal stents and 502 (70.5%) with plastic stents. The majority of patients (86.4%) had pancreatic cancer. The rate of endoscopic re-intervention after preoperative biliary drainage was significantly lower in the metal stent (3.4%) than in the plastic stent (14.8%) group (p < 0.0001). The rate of postoperative pancreatic fistula was significantly lower in the meta stent group as well (5.1% versus 11.8%, p = 0.04). The rate of post-operative surgical complications and of - post-operative mortality did not differ between the two groups.
CONCLUSIONS
Although the present systematic review and meta-analysis demonstrates that metal stent are more effective than plastic stents for PBD in patients with resectable periampullary tumors, randomized controlled trials are needed in order to confirm these data with a higher level of evidence.
Topics: Ampulla of Vater; Biliary Tract Surgical Procedures; Drainage; Humans; Jaundice, Obstructive; Metals; Pancreatectomy; Pancreatic Neoplasms; Plastics; Postoperative Complications; Preoperative Care; Risk Factors; Stents
PubMed: 27296728
DOI: 10.1016/j.ejso.2016.05.001 -
Biological Trace Element Research Sep 2020The relationship between thyroid hormones metabolism and trace element levels has biological plausibility; however, previous reports that compared trace element levels... (Meta-Analysis)
Meta-Analysis Review
The relationship between thyroid hormones metabolism and trace element levels has biological plausibility; however, previous reports that compared trace element levels in patients with hypothyroidism and healthy individuals yielded conflicting results. Therefore, the aim of this meta-analysis was to investigate the association between selected trace elements (i.e., selenium (Se), zinc (Zn), iron (Fe), manganese (Mn), copper (Cu), lead (Pb)), and magnesium (Mg) concentrations in patients with hypothyroidism and healthy controls. Electronic databases, including PubMed, Scopus, Embase, and Science Direct, were searched systematically until September 2019. Thirty-two observational studies were included in the final analyses. Hedges' g tests were used to estimate effect sizes, as trace element concentrations were reported using different measurement units across the studies. Selenium (Hedges' g = - 0.52; 95% CI = [- 1.05, - 0.002]; P = 0.049) and Zn (Hedges' g = - 0.86; 95% CI = [- 1.66, - 0.06]; P = 0.035) concentrations were significantly lower, whereas Pb concentrations were significantly higher (Hedges' g = 0.34; 95% CI = [0.10, 0.59]; P = 0.006) in patients with hypothyroidism compared with healthy controls. There were no differences in the concentrations of Fe, Cu, Mn, and Mg between the groups. Patients with hypothyroidism exhibited lower Se and Zn and increased Pb concentrations compared with healthy controls. High-quality studies with larger sample sizes are required to explicate the link between trace element status and hypothyroidism.
Topics: Copper; Humans; Hypothyroidism; Selenium; Trace Elements; Zinc
PubMed: 31820354
DOI: 10.1007/s12011-019-01963-5 -
Medicina (Kaunas, Lithuania) May 2021HIV has been a serious global health concern since its discovery, with about 37.9 million people living with HIV worldwide as of 2018. Sub-Saharan Africa (SSA) accounts... (Review)
Review
HIV has been a serious global health concern since its discovery, with about 37.9 million people living with HIV worldwide as of 2018. Sub-Saharan Africa (SSA) accounts for 68% of the infection and contributed 74% of the 1.5 million deaths in 2013 despite having only 12% of the total world population residing in the region. This systematic review has attempted to determine the association between heavy metal toxicity and the occurrence of non-communicable diseases in the HIV/AIDS population. Three databases were systematically searched: PubMed, Scopus, and Google Scholar for studies written in English and published between 1 April 2000 and 12 April 2020. Studies were excluded if the main outcomes were not measured or did not meet the inclusion criteria. All the six included studies are cross-sectional in design, and therefore were evaluated using the STROBE checklist. The data extraction was done using an extraction table; the ratio of female to male participants included in the study was 1.09:1. Qualitative analysis was used due to the heterogeneity in the heavy metal biomarkers and the outcome measured by the included studies. Two studies compared the concentration of heavy metals in HIV-positive and HIV-negative participants while one compared the levels between HAART-naïve and HAART-treated participants, and three determined the association between heavy metal toxicity and non-communicable diseases (liver fibrosis, anaemia, and reproductive parameters, respectively) in HIV-positive patients. Blood lead, cadmium, and mercury levels were higher in HIV-seropositive than -seronegative subjects, whereas serum zinc level was lower in HIV-seropositive than -seronegative subjects, but the causal association between heavy metals and non-communicable diseases in HIV subjects is largely unknown. Interdisciplinary research between nutrition, toxicology, and human health is envisaged for primary and secondary prevention and treatment.
Topics: Africa South of the Sahara; Cross-Sectional Studies; Female; HIV Infections; Humans; Male; Metals, Heavy; Noncommunicable Diseases
PubMed: 34068196
DOI: 10.3390/medicina57050492 -
Environmental Research Feb 2023Endocrine disrupting chemicals (EDCs) are exogenous substances recognised as relevant tumourigenic chemicals. Studies show that even EDCs which were long abolished are... (Review)
Review
INTRODUCTION
Endocrine disrupting chemicals (EDCs) are exogenous substances recognised as relevant tumourigenic chemicals. Studies show that even EDCs which were long abolished are still contributing to the increasing incidence of neoplasia.
AIM
To investigate the association between human exposure to EDCs and the risk of endocrine-related tumours: breast, prostate, thyroid, uterus, testis, and ovary.
METHODS
A systematic review using PubMed, Scopus, and Embase was conducted, searching for original observational studies published between 1980 and 2020, approaching EDCs exposure and endocrine tumourigenic risk in humans. We comprised neoplasia of six endocrine organs. We included all the studies on EDCs reporting tumour odds ratio, risk ratio, or hazard ratio. Study levels of confidence and risk of bias were accessed applying accredited guidelines. Human-made accidents and natural EDCs were not considered in the present study.
RESULTS
Our search returned 3271 papers. After duplicate removal and screening, only 237 papers were included (corresponding to 268 records). EDCs were grouped from the most frequently (pesticides) to the least frequently studied (salts). The most tumourigenic EDC groups were phthalates (63%), heavy metals (54%), particulate matter (47%), and pesticides (46%). Pesticides group comprised the highest number of retrieved studies (n = 133). Increased neoplasia risk was found in 43-67% of the studies, with a lower value for ovary (43%) and a higher value for thyroid (67%).
CONCLUSIONS
The innovative nature of our review comes from including human studies of six endocrine-related neoplasia aiming to understand the contribution of specific EDCs groups to each organ's tumourigenesis. Thyroid was the organ presenting the highest cancer risk after EDC exposure which may explain the increasing thyroid cancer incidence. However, detailed and controlled works reporting the effects of EDCs are scarce, probably justifying conflicting results. Multinational and multicentric human studies with biochemical analysis are needed to achieve stronger and concordant evidence.
Topics: Male; Female; Humans; Endocrine Disruptors; Endocrine System; Pesticides; Testis; Metals, Heavy
PubMed: 36460069
DOI: 10.1016/j.envres.2022.114869 -
International Journal of Surgery... Apr 2022The objective of this study was to compare cup survival and the incidence of adverse events associated with the use of trabecular metal (TM) and non-TM cups for... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The objective of this study was to compare cup survival and the incidence of adverse events associated with the use of trabecular metal (TM) and non-TM cups for acetabular revision surgery.
METHODS
The MEDLINE, EMBASE, and Cochrane Library databases were searched for comparative studies that reported cup survival and the incidence of adverse events associated with the use of TM and non-TM cups for acetabular revision surgery. Primary outcomes included cup survival, aseptic loosening, dislocation, and infection.
RESULTS
The meta-analysis included 6 studies that involved 13,864 total hip arthroplasty (THA) revisions who underwent acetabular revision surgery with TM (n = 5,619) or non-TM (n = 8,245) cups. The meta-analysis demonstrated no significant difference in cup survival using re-revision for any reason or aseptic loosening as the endpoint following acetabular revision surgery with TM or non-TM cups (HR = 0.96; [95% CI, 0.84-1.09]; HR = 1.29; [95% CI, 0.70-2.38]). Pooled data indicated that the overall incidence of adverse events for TM or non-TM cups was 6.8% (382/5,289) and 9.0% (725/8,083), respectively, and not significantly different (OR = 0.91; [95% CI, 0.80-1.04]). The incidence of aseptic loosening and infection were significantly lower (OR = 0.75; [95% CI, 0.58-0.96]; OR = 0.70; [95% CI, 0.54-0.90]) and the incidence of dislocation was significantly higher (OR = 1.53; [95% CI, 1.22-1.91]) for TM compared to non-TM cups.
CONCLUSION
This review was the first to use reconstructed time-to-event data to find that there was no difference in survival of TM and non-TM cups in acetabular revision surgery. Overall, fewer adverse events were associated with the use of TM compared to non-TM cups, but the difference was not significant. The incidence of aseptic loosening and infection were significantly lower and the incidence of dislocation was significantly higher for TM compared to non-TM cups. This information is expected to guide orthopedic surgeons in the selection of appropriate acetabular components for THA revision.
Topics: Arthroplasty, Replacement, Hip; Follow-Up Studies; Hip Prosthesis; Humans; Joint Dislocations; Metals; Prosthesis Design; Prosthesis Failure; Registries; Reoperation; Retrospective Studies
PubMed: 35288338
DOI: 10.1016/j.ijsu.2022.106597 -
The Science of the Total Environment Apr 2022The etiology of sporadic amyotrophic lateral sclerosis (ALS) is still unclear. We evaluate environmental factors suspected to be associated with ALS for their potential... (Review)
Review
The etiology of sporadic amyotrophic lateral sclerosis (ALS) is still unclear. We evaluate environmental factors suspected to be associated with ALS for their potential linkage to disease causality and to model geographic distributions of susceptible populations and expected cases worldwide. A PRISMA systematic literature review was performed 2021. Bradford Hill criteria were used to identify and rank environmental factors and a secondary review of ALS diagnoses in population studies and ALS case or cohort studies was conducted. Prevalence rate projection informed estimates of impacted regions and populations. Among 1710 papers identified, 258 met the inclusion criteria, of which 173 responded to at least one of nine Bradford Hill criteria among 83 literature-identified ALS environmental factors. Environmental determinants of ALS in order of decreasing significance were β-N-methylamino-L-alanine (BMAA), formaldehyde, selenium, and heavy metals including manganese, mercury, zinc, and copper. Murine animal models were the most common methodology for exploring environmental factors. Another line of investigation of 62 population exposure studies implicated the same group of environmental agents (mean odds ratios): BMAA (2.32), formaldehyde (1.54), heavy metals (2.99), manganese (3.85), mercury (2.74), and zinc (2.78). An age-adjusted incidence model estimated current total ALS cases globally at ~85,000 people compared to only ~1600 cases projected from the reported ALS incidence in the literature. Modeling with the prevalence microscope equation forecasted an increase in U.S. ALS cases from 16,707 confirmed in 2015 to ~22,650 projected for 2040. Two orthogonal methods employed implicate BMAA, formaldehyde, manganese, mercury, and zinc as environmental factors with strong ALS associations. ALS cases likely are significantly underreported globally, and high vulnerability exists in regions with large aging populations. Recent studies on other diseases with environmental determinants suggest the need to consider additional potential triggers and mechanisms, including exposures to microbial agents and epigenetic modifications.
Topics: Amyotrophic Lateral Sclerosis; Animals; Formaldehyde; Humans; Mercury; Mice; Selenium; Zinc
PubMed: 34971691
DOI: 10.1016/j.scitotenv.2021.152504 -
Environmental Research Jun 2021Toenails have been used as biomarkers of exposure to toxic metals, but their validity for this purpose is not yet clear and might differ depending on the specific agent.... (Review)
Review
Toenails have been used as biomarkers of exposure to toxic metals, but their validity for this purpose is not yet clear and might differ depending on the specific agent. To evaluate this issue, we reviewed the literature on: a) the time-window of exposure reflected by toenails; b) the reproducibility of toenail toxic-metal levels in repeated measures over time; c) their relationship with other biomarkers of exposure, and; d) their association with potential determinants (i.e. sociodemographic, anthropometric, or lifestyle characteristics) or with sources of exposure like diet or environmental pollution. Thus, we performed a systematic review, searching for articles that provided original data for levels of any of the following toxic metals in toenails: aluminum, beryllium, cadmium, chromium, mercury, nickel, lead, thallium and uranium. We identified 88 articles, reporting data from 67 different research projects, which were quite heterogeneous with regard to population profile, sample size and analytical technique. The most commonly studied metal was mercury. Concerning the time-window of exposure explored by toenails, some reports indicate that toenail cadmium, nickel and lead may reflect exposures that occurred 7-12 months before sampling. For repeated samples obtained 1-6 years apart, the range of intraindividual correlation coefficients of aluminum, chromium and mercury was 0.33-0.56. The correlation of toxic metal concentrations between toenails and other matrices was higher for hair and fingernails than for urine or blood. Mercury levels were consistently associated with fish intake, while other toxic metals were occasionally associated with specific sources (e.g. drinking water, place of residence, environmental pollution, and occupation). The most frequently evaluated health endpoints were cardiovascular diseases, cancer, and central nervous system diseases. Available data suggest that toenail mercury levels reflected long-term exposures and showed positive associations with fish intake. The lack of standardization in sample collection, quality control, analytical techniques and procedures - along with the heterogeneity and conflicting results among studies - mean it is still difficult to conclude that toenails are a good biomarker of exposure to toxic metals. Further studies are needed to draw solid conclusions about the suitability of toenails as biomarkers of exposure to toxic metals.
Topics: Animals; Biomarkers; Environmental Exposure; Mercury; Metals; Nails; Reproducibility of Results
PubMed: 33753073
DOI: 10.1016/j.envres.2021.111028 -
Osteoporosis International : a Journal... Sep 2020The relationship between heavy metal exposure and risk of osteopenia or osteoporosis has biological plausibility, yet it remains inconclusive; therefore, we conducted a... (Meta-Analysis)
Meta-Analysis Review
The relationship between heavy metal exposure and risk of osteopenia or osteoporosis has biological plausibility, yet it remains inconclusive; therefore, we conducted a systematic review and meta-analysis to evaluate the associations between exposure to heavy metals (i.e., cadmium, lead, and mercury) and the risk of osteopenia or osteoporosis. Databases of MEDLINE, Embase, Scopus, and Web of Science were searched through November 2019, to identify studies that evaluated the relationship between exposure to cadmium, lead, and mercury and risk of osteopenia or osteoporosis in adults. Fourteen eligible studies were included. Effect sizes expressed as pooled odds ratios (OR) and 95% confidence intervals (CI) were estimated using weighted random-effect models. Exposure to cadmium (OR = 1.35; 95% CI: 1.17 to 1.56; P ≤ 0.001) and lead (OR = 1.15; 95% CI: 1.00 to 1.32; P = 0.05) was associated with an increased risk of osteopenia or osteoporosis, unlike mercury. Subgroup analyses showed cadmium exposure increased the risk of osteopenia or osteoporosis in older (> 65 yrs.; OR = 1.43; 95%CI: 1.08 to 1.88, P = 0.01) compared with younger (18-65 yrs.; OR = 1.24; 95% CI: 1.02 to 1.52, P = 0.03) adults. Also, lead exposure increased the risk in men (OR = 1.55; 95% CI: 1.15 to 2.09, P = 0.007) unlike in women. By contrast to urinary levels, blood (OR = 1.26; 95% CI: 1.08 to 1.47, P = 0.003) and dietary (OR = 1.46; 95% CI: 1.28 to 1.67, P < 0.001) levels of cadmium were associated with an increased risk of osteopenia or osteoporosis. Exposure to cadmium and lead may be associated with an increased risk of osteopenia or osteoporosis, although high heterogeneity was detected.
Topics: Adult; Aged; Bone Diseases, Metabolic; Cadmium; Female; Humans; Male; Mercury; Metals, Heavy; Osteoporosis
PubMed: 32361950
DOI: 10.1007/s00198-020-05429-6