Association of genetic liability to smoking initiation with e-cigarette use in young adults: A cohort study

BackgroundTobacco smoking and e-cigarette use are strongly associated, but it is currently unclear whether this association is causal, or due to shared factors that influence both behaviours such as a shared genetic liability. The aim of this study was to investigate whether polygenic risk scores (PRS) for smoking initiation are associated with ever use of e-cigarettes.Methods and findingsSmoking initiation PRS were calculated for young adults (N = 7,859, mean age = 24 years, 51% male) of European ancestry in the Avon Longitudinal Study of Parents and Children, a prospective birth cohort study initiated in 1991. PRS were calculated using the GWAS & Sequencing Consortium of Alcohol and Nicotine use (GSCAN) summary statistics. Five thresholds ranging from 5 × 10⁻⁸ to 0.5 were used to calculate 5 PRS for each individual. Using logistic regression, we investigated the association between smoking initiation PRS and the main outcome, self-reported e-cigarette use (n = 2,894, measured between 2016 and 2017), as well as self-reported smoking initiation and 8 negative control outcomes (socioeconomic position at birth, externalising disorders in childhood, and risk-taking in young adulthood). A total of 878 young adults (30%) had ever used e-cigarettes at 24 years, and 150 (5%) were regular e-cigarette users at 24 years. We observed positive associations of similar magnitude between smoking initiation PRS (created using the p < 5 × 10⁻⁸ threshold) and both smoking initiation (odds ratio (OR) = 1.29, 95% CI 1.19 to 1.39, p < 0.001) and ever e-cigarette use (OR = 1.24, 95% CI 1.14 to 1.34, p < 0.001) by the age of 24 years, indicating that a genetic predisposition to smoking initiation is associated with an increased risk of using e-cigarettes. At lower p-value thresholds, we observed an association between smoking initiation PRS and ever e-cigarette use among never smokers. We also found evidence of associations between smoking initiation PRS and some negative control outcomes, particularly when less stringent p-value thresholds were used to create the PRS, but also at the strictest threshold (e.g., gambling, number of sexual partners, conduct disorder at 7 years, and parental socioeconomic position at birth). However, this study is limited by the relatively small sample size and potential for collider bias.ConclusionsOur results indicate that there may be a shared genetic aetiology between smoking and e-cigarette use, and also with socioeconomic position, externalising disorders in childhood, and risky behaviour more generally. This indicates that there may be a common genetic vulnerability to both smoking and e-cigarette use, which may reflect a broad risk-taking phenotype.

Jasmine Khouja and co-workers study genetic predictors of tobacco smoking initiation and e-cigarette use.     

Electronic Cigarette Use among Irish Youth: A Cross Sectional Study of Prevalence and Associated Factors

PurposeTo examine prevalence of, and factors associated with, e-cigarette use among young people aged 16-17 in Ireland.MethodsIn 2014, a representative sample of 821 young people aged 16-17 recruited from secondary schools completed a pen and paper survey on e-cigarette use, tobacco use, and socio-demographic items.FindingsA total of 23.8% of respondents had used e-cigarettes at least once. Dual trial of tobacco and e-cigarettes was common with 69.5% of regular smokers and 30.4% of ‘ever’ smokers having tried e-cigarettes and 10.6% of current smokers using e-cigarettes regularly. 4.2% of never smokers have tried e-cigarettes. Overall, current e-cigarette use (once a month or more) was low (3.2%). Binary logistic regression conducted through generalized estimating equations (GEE) determined that controlling for other variables, current tobacco use and ‘ever’ tobacco use predicted ever e-cigarette use. Gender and school-level socioeconomic status were also independent predictors of ever e-cigarette use. Gender stood as the only predictor of on-going e-cigarette use, with males being more likely to regularly use e-cigarettes at least once a month.ConclusionsE-cigarette use among 16-17 year olds in Ireland is of note, with nearly a quarter of students having tried them. Concurrent or experimental use of e-cigarettes and tobacco is more common than sole use, while a small number have tried e-cigarettes without having tried tobacco.     

Perceptions of e-cigarette harm among cancer survivors: Findings from a nationally representative survey

BackgroundThe growth in e-cigarette use may be driven by the perception that they are a safer, healthier alternative to conventional cigarettes. However, their long-term health implications are not well known and use is discouraged by most cancer societies. It is currently unclear how cancer survivors perceive the risks associated with e-cigarette and how this may influence use in this population.MethodsA cross-sectional analysis was conducted using the Health Information National Trends Survey (HINTS) (Years 2017–2019). Our primary study outcome was the perception of harm associated with e-cigarettes compared to traditional cigarettes among adults with and without a self-reported history of cancer. We used logistic regression analyses assessing the association of a cancer history with the perception that e-cigarettes are as much or more harmful than cigarettes.ResultsA total of 11,846 respondents (weighted population estimate 243,728,483) were included. Of these, 26.6% reported a history of cancer. The proportion of cancer survivors who perceived e-cigarettes to be as much or more harmful than conventional cigarettes was similar to non-cancer respondents (70.6% vs 68.3%, P = 0.35). There was no difference in perception of harm among cancer and non-cancer respondents, adjusted for sociodemographic factors (OR 0.82, 95% CI 0.6–1.1). Past (OR 9.06, 95% Cl 5.06–16.20) and never e-cigarette use (OR 23.40, 95% Cl 13.56–40.38) as well as having a history of cardiopulmonary disease (OR 1.28, 95% Cl 1.05–1.56) was associated with higher odds of perceiving e-cigarettes to be as much or more harmful.ConclusionCancer survivors commonly perceive e-cigarettes to be as much or more harmful than traditional cigarettes though these findings are similar to perceptions among adults without a history of cancer. There is a strong association with avoidance of e-cigarette products among those who perceive them to be harmful.     

Low-level environmental lead and cadmium exposures and dyslipidemia in adults: Findings from the NHANES 2005–2016

BackgroundPrevious experimental and occupational health studies have shown the toxic effects of relatively high-level cadmium and lead on lipid metabolism. However, limited studies investigated the relationships between serum lipid levels and exposure to low-level lead and cadmium in adults.ObjectiveTo investigate the associations between lead and cadmium levels in blood and dyslipidemia in adults.MethodsA retrospective cross-sectional study of 7,457 adults aged 20–79 years who were recruited in the National Health and Nutrition Examination Survey (NHANES, 2005–2016) was conducted. Multivariate linear and logistic regressions were used to examine the associations of blood lead and cadmium levels with serum lipid profiles and risk of dyslipidemia, respectively.ResultsThe weighted geometric means [95% confidence intervals (CIs)] of lead and cadmium in blood were 1.23 (1.21, 1.25) μg/dL and 0.36 (0.35, 0.37) μg/L, respectively. Blood lead was significantly associated with serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), and apolipoprotein B (Apo B) levels after adjusting for covariates. Compared with the adults in the lowest blood lead quartile (≤0.76 μg/dL), those in the highest lead quartile (>1.90 μg/dL) had higher risks of elevated TC (OR = 1.88, 95% CI: 1.59–2.22), non-HDL-C (OR = 1.59, 95% CI: 1.33–1.91), LDL-C (OR = 1.68, 95% CI: 1.41–1.99) and Apo B (OR = 2.00, 95% CI: 1.46–2.73). However, the single effect of cadmium exposure and the joint effect of lead and cadmium exposures on dyslipidemia were not observed.ConclusionBlood lead well below the current recommended level was positively associated with the risk of dyslipidemia in adults, while the low-level cadmium exposure currently observed in adults did not show any significant associations with lipid levels.     

Reported electronic cigarette use among adolescents in the Niagara region of Ontario

Background:Use of electronic cigarettes (e-cigarettes) among adolescents has not been fully described, in particular their motivations for using them and factors associated with use. We sought to evaluate the frequency, motivations and associated factors for e-cigarette use among adolescents in Ontario.Methods:We conducted a cross-sectional study in the Niagara region of Ontario, Canada, involving universal screening of students enrolled in grade 9 in co-operation with the Heart Niagara Inc. Healthy Heart Schools’ Program (for the 2013–2014 school year). We used a questionnaire to assess cigarette, e-cigarette and other tobacco use, and self-rated health and stress. We assessed household income using 2011 Canadian census data by matching postal codes to census code.Results:Of 3312 respondents, 2367 answered at least 1 question in the smoking section of the questionnaire (1274 of the 2367 respondents [53.8%] were male, with a mean [SD] age of 14.6 [0.5] yr) and 2292 answered the question about use of e-cigarettes. Most respondents to the questions about use of e-cigarettes (n = 1599, 69.8%) had heard of e-cigarettes, and 380 (23.8%) of these respondents had learned about them from a store sign or display. Use of e-cigarettes was reported by 238 (10.4%) students. Most of the respondents who reported using e-cigarettes (171, 71.9%) tried them because it was “cool/fun/new,” whereas 14 (5.8%) reported using them for smoking reduction or cessation. Male sex, recent cigarette or other tobacco use, family members who smoke and friends who smoke were strongly associated with reported e-cigarette use. Reported use of e-cigarettes was associated with self-identified fair/poor health rating (odds ratio [OR] 1.9 (95% confidence interval [CI] 1.2–3.0), p < 0.001), high stress level (OR 1.7 (95% CI 1.1–2.7), p < 0.001) and lower mean (33.4 [8.4] × $1000 v. 36.1 [10.7] × $1000, p = 0.001) and median [interquartile range] (26.2 [5.6] × $1000 v. 28.1 [5.7] × $1000) household incomes.Interpretation:Use of e-cigarettes is common among adolescents in the Niagara region and is associated with sociodemographic features. Engaging in seemingly exciting new behaviours appears to be a key motivating factor rather than smoking cessation.Electronic cigarettes (e-cigarettes) are novel devices that are designed to mimic the physical and tactile experience of conventional cigarettes while producing a smoke-free vapour. They have quickly gained popularity despite limited evidence regarding the health risks associated with their use and a lack of regulation.¹ In addition, existing literature about e-cigarettes suggests that they may not be effective for achieving smoking reduction or cessation, a use for which they are often marketed.^1–3 Given their physical similarities to conventional cigarettes, there are concerns that the increasing use of e-cigarettes may result in the “renormalization” of cigarette smoking.^4,5 Previous studies have suggested that use of e-cigarettes among adolescents and young adults may be associated with use of and exposure to tobacco.^1,6,7Rates of the use of e-cigarettes at least once among high school students in the United States have increased annually.^6,8 Among adolescents in Canada, use of e-cigarettes is now more common than cigarette use.⁹ However, questions still remain regarding the motivations and factors associated with e-cigarette use among adolescents. Therefore, we sought to evaluate the frequency, motivations and associated factors for use of e-cigarettes by students in grade 9 who were undergoing universal school-based screening for cardiovascular risk factors in the Niagara region in Ontario.     

Patterns and associations of smoking and electronic cigarette use among survivors of tobacco related and non-tobacco related cancers: A nationally representative cross-sectional analysis

BackgroundTobacco-use among cancer survivors leads to preventable morbidity, mortality, and increased healthcare costs. We sought to explore the prevalence of smoking and e-cigarette use among survivors of tobacco and non-tobacco related cancers.MethodsA cross-sectional analysis was conducted using the 2015–2018 National Health Interview Survey. Our primary outcome was the prevalence of current cigarette smoking or e-cigarette use among adults with self-reported history of tobacco related or non-tobacco related cancer. Logistic regression analysis was to assess the association of reported cancer type with cigarette smoking or e-cigarette use. Secondary outcomes included yearly trends and dual use.ResultsA total of 12,984 respondents reported a history of cancer, representing a weighted estimate of 5,060,059 individuals with a history of tobacco-related malignancy and 17,583,788 with a history of a tobacco and non-tobacco related cancer, respectively. Survivors of tobacco-related cancers had a significantly higher prevalence of current cigarette use (18.2 % vs 9.7 %, P < 0.0001), e-cigarette use (2.7 % vs 1.6 %, P < 0.0001) and similar rates of dual use. The prevalence of cigarette smoking among all survivors increased as time increased from the year of diagnosis up to 2 years post-diagnosis (P = 0.047). Odds of reporting current cigarette smoking use was higher for survivors of tobacco-related cancers, adjusted for sociodemographic factors (OR1.69, 95 % CI 1.44−1.99).ConclusionsSurvivors of tobacco-related cancers have a higher prevalence of current cigarette smoking and e-cigarette use compared to survivors of non-tobacco related cancers. There was a sequential increase in the prevalence of cigarette use during each subsequent year from the time of a new cancer diagnosis, underscoring the need for long term tobacco cessation support among newly diagnosed adults with cancer.     

Electronic Cigarette and Traditional Cigarette Use among Middle and High School Students in Florida, 2011–2014

Recent youth trends in the prevalence of e-cigarette and traditional cigarette use in Florida were examined in a cross-sectional, representative state sample from 2011 to 2014. Traditional cigarette use among youth declined during the study period. Experimentation with and past 30-day use of e-cigarettes among Florida youth tripled over 4 years. Past 30-day e-cigarette use exceeded traditional cigarette use in 2014; 10.8% of high school and 4.0% of middle school students reported recent e-cigarette use, compared with 8.7% of high school and 2.9% of middle school students for traditional cigarettes (P<0.001). By 2014, 20.5% of high school and 8.5% of middle school students reported ever use of e-cigarettes. Among ever e-cigarette users in 2014, 30.3% of high school and 42.2% of middle school students had never smoked traditional cigarettes. Given the concern that significant rates of e-cigarette use by U.S. adolescents may have a negative effect on public health, further review of e-cigarette advertising, marketing, sales, and use among U.S. youth is warranted.     

E-Cigarettes and Smoking Cessation: Evidence from a Systematic Review and Meta-Analysis

Background

E-cigarettes are currently being debated regarding their possible role in smoking cessation and as they are becoming increasingly popular, the research to date requires investigation.

Objectives

To investigate whether the use of e-cigarettes is associated with smoking cessation or reduction, and whether there is any difference in efficacy of e-cigarettes with and without nicotine on smoking cessation.

Data Sources

A systematic review of articles with no limit on publication date was conducted by searching PubMed, Web of Knowledge and Scopus databases.

Methods

Published studies, those reported smoking abstinence or reduction in cigarette consumption after the use of e-cigarettes, were included. Studies were systematically reviewed, and meta-analyses were conducted using Mantel-Haenszel fixed-effect and random-effects models. Degree of heterogeneity among studies and quality of the selected studies were evaluated.

Results

Six studies were included involving 7,551 participants. Meta-analyses included 1,242 participants who had complete data on smoking cessation. Nicotine filled e-cigarettes were more effective for cessation than those without nicotine (pooled Risk Ratio 2.29, 95%CI 1.05-4.97). Amongst 1,242 smokers, 224 (18%) reported smoking cessation after using nicotine-enriched e-cigarettes for a minimum period of six months. Use of such e-cigarettes was positively associated with smoking cessation with a pooled Effect Size of 0.20 (95%CI 0.11-0.28). Use of e-cigarettes was also associated with a reduction in the number of cigarettes used.

Limitations

Included studies were heterogeneous, due to different study designs and gender variation. Whilst we were able to comment on the efficacy of nicotine vs. non-nicotine e-cigarettes for smoking cessation, we were unable to comment on the efficacy of e-cigarettes vs. other interventions for cessation, given the lack of comparator groups in the studies included in this meta-analysis.

Conclusions

Use of e-cigarettes is associated with smoking cessation and reduction. More randomised controlled trials are needed to assess effectiveness against other cessation methods.     

Attitudes towards Electronic Cigarettes Regulation in Indoor Workplaces and Selected Public and Private Places: A Population-Based Cross-Sectional Study

Background

Currently, there is an intensive debate about the regulation of the use of electronic cigarettes (e-cigarettes) in indoor places. The aim of this study was to assess the attitudes toward e-cigarette use in indoor workplaces and selected public and private venues among the general population in Barcelona (Spain) in 2013–2014.

Methods

This is a cross-sectional study of a representative sample of the population of Barcelona (n = 736). The field work was conducted between May 2013 and February 2014. We computed the prevalence and the adjusted odds ratios (OR) derived from multivariable logistic regression models.

Results

The awareness of e-cigarettes was 82.3%. Forty five percent of respondents did not agree with the use of e-cigarettes in public places and 52.3% in workplaces. The proportion of disapproval of the use of e-cigarettes in indoor places was higher at 71.5% for schools and 65.8% for hospitals and health care centers; while the prevalence of disapproval of e-cigarette use in homes and cars was lower (18.0% and 32.5%, respectively). Respondents who disagreed on the use of e-cigarettes in indoor workplaces were more likely to be older (OR = 1.64 and 1.97 for groups 45–64 and ≧65 years old, respectively), those with a high educational level (OR = 1.60), and never and former smokers (OR = 2.34 and 2.16, respectively). Increased scores in the Fagerström test for cigarette dependence were also related to increased support for their use.

Conclusions

Based on this population based study, half of the general population of Barcelona does not support the use of e-cigarettes in indoor workplaces and public places, with the percentage reaching 65% for use in schools, hospitals and health care centers. Consequently, there is good societal support in Spain for the politicians and legislators to promote policies restricting e-cigarettes use in workplaces and public places, including hospitality venues.     

Cadmium exposure and the risk of prostate cancer among Nigerian men: Effect modification by zinc status

BackgroundProstate cancer (PCa) may result from an interplay between many factors including exposure to trace elements. This study examined the association between cadmium exposure and PCa among Nigerian men and evaluated possible modification of this effect by zinc status.MethodsThis case-control study involved men with histologically confirmed PCa (n = 82), benign prostatic hyperplasia (BPH; n = 93) and controls (n = 98), aged between 40 and 80 years. Study participants were recruited from the main teaching hospital that draws clients from the entire Anambra State in South-Eastern Nigeria. Blood and urine samples were collected from these participants and were analyzed for trace elements using ICP-MS. Statistical models were used to assess the exposure risk for cadmium exposure as well as the mediating effect of zinc status.ResultsAmong men with prostatic disorders (case-case analysis), every 10-fold increase in urinary cadmium was associated with increased risk of PCa (adjusted odds ratios: 2.526; 95% CI: 1.096–5.821). Men in the highest blood zinc quartile had lower odds of PCa compared to the lowest quartile (AOR: 0.19; 95% CI, 0.06–0.54; p-for trend = 0.001). Zinc-specific effect was observed in this group: every 10-fold increase in urinary cadmium was associated with increased risk of PCa among men with creatinine-adjusted urinary zinc levels below the median value (AOR: 8.46; 95% CI: 1.97 –36.39) but not in those above the median value (AOR: 1.55; 95% CI: 0.45 – 5.39).ConclusionHigher exposure to cadmium may be associated with increased risk of PCa in Nigeria and probably other countries with high prevalence of Zn deficiency. These results point to the need to consider co-occurring trace metals in any effort to mitigate the toxicity of Cd in the environment.     

The sex-specific effects of blood lead,mercury, and cadmium levels on hepatic steatosis and fibrosis: Korean nationwide cross-sectional study

AimThe potential effects of heavy metals on non-alcoholic fatty liver disease (NAFLD) remain unknown. We investigated the sex-specific relationships of blood lead (BPb), mercury (BHg), and cadmium (BCd) levels with hepatic steatosis (HS) and fibrosis (HF).MethodWe included 4420 participants from the 2016–2017 Korea National Health and Nutrition Examination Survey. High-risk alcoholics and patients with chronic hepatitis B or C infections or liver cirrhosis were excluded. We calculated the hepatic steatosis index (HSI) and fibrosis-4 index (FIB-4) values; we defined the presence of HS and HF as an HSI ≥ 36 and FIB-4 score >2.67, respectively. We adjusted for age, smoking and alcohol consumption statuses, hypertension, obesity, diabetes, hypertriglyceridemia, and BPb, BHg, and BCd levels.ResultIn males (n = 1860), the HSI was correlated negatively with the BPb level and positively with the BHg level (both p < 0.01). The FIB-4 score was correlated positively with the BPb and BCd levels (both p < 0.01). In females (n = 2560), the HSI and FIB-4 score were correlated positively with the BPb, BHg, and BCd levels (all p < 0.01). After adjustments, the BHg level increased the risk of HS in both males (OR = 1.065, p = 0.003) and females (OR = 1.061, p = 0.048), and the BCd level increased the risk of HF in females (OR = 1.668, p = 0.012).ConclusionBlood heavy metal levels were generally correlated positively with the HSI and FIB4 score, more so in females than males. The BHg level was associated with HS in males and females, and the BCd level was associated with HF in females. Further studies on NAFLD progression according to heavy metal status and sex are warranted.     

Association of Urinary Metal Profiles with Altered Glucose Levels and Diabetes Risk: A Population-Based Study in China

Background

Elevated heavy metals and fasting plasma glucose (FPG) levels were both associated with increased risk of cardiovascular diseases. However, studies on the associations of heavy metals and essential elements with altered FPG and diabetes risk were limited or conflicting. The objective of this study was to evaluate the potential associations of heavy metals and essential trace elements with FPG and diabetes risk among general Chinese population.

Methods

We conducted a cross-sectional study to investigate the associations of urinary concentrations of 23 metals with FPG, impaired fasting glucose (IFG) and diabetes among 2242 community-based Chinese adults in Wuhan. We used the false discovery rate (FDR) method to correct for multiple hypothesis tests.

Results

After adjusting for potential confounders, urinary aluminum, titanium, cobalt, nickel, copper, zinc, selenium, rubidium, strontium, molybdenum, cadmium, antimony, barium, tungsten and lead were associated with altered FPG, IFG or diabetes risk (all P< 0.05); arsenic was only dose-dependently related to diabetes (P< 0.05). After additional adjustment for multiple testing, titanium, copper, zinc, selenium, rubidium, tungsten and lead were still significantly associated with one or more outcomes (all FDR-adjusted P< 0.05).

Conclusions

Our results suggest that multiple metals in urine are associated with FPG, IFG or diabetes risk. Because the cross-sectional design precludes inferences about causality, further prospective studies are warranted to validate our findings.     

Electronic Cigarettes Efficacy and Safety at 12 Months: Cohort Study

Objective

To evaluate the safety and efficacy as a tool of smoking cessation of electronic cigarettes (e-cigarettes), directly comparing users of e-cigarettes only, smokers of tobacco cigarettes only, and smokers of both.

Design

Prospective cohort study. Final results are expected in 2019, but given the urgency of data to support policies on electronic smoking, we report the results of the 12-month follow-up.

Data Sources

Direct contact and structured questionnaires by phone or via internet.

Methods

Adults (30–75 years) were included if they were smokers of ≥1 tobacco cigarette/day (tobacco smokers), users of any type of e-cigarettes, inhaling ≥50 puffs weekly (e-smokers), or smokers of both tobacco and e-cigarettes (dual smokers). Carbon monoxide levels were tested in a sample of those declaring tobacco smoking abstinence.

Main Outcome Measures

Sustained smoking abstinence from tobacco smoking at 12 months, reduction in the number of tobacco cigarettes smoked daily.

Data Synthesis

We used linear and logistic regression, with region as cluster unit.

Results

Follow-up data were available for 236 e-smokers, 491 tobacco smokers, and 232 dual smokers (overall response rate 70.8%). All e-smokers were tobacco ex-smokers. At 12 months, 61.9% of the e-smokers were still abstinent from tobacco smoking; 20.6% of the tobacco smokers and 22.0% of the dual smokers achieved tobacco abstinence. Adjusting for potential confounders, tobacco smoking abstinence or cessation remained significantly more likely among e-smokers (adjusted OR 5.19; 95% CI: 3.35–8.02), whereas adding e-cigarettes to tobacco smoking did not enhance the likelihood of quitting tobacco and did not reduce tobacco cigarette consumption. E-smokers showed a minimal but significantly higher increase in self-rated health than other smokers. Non significant differences were found in self-reported serious adverse events (eleven overall).

Conclusions

Adding e-cigarettes to tobacco smoking did not facilitate smoking cessation or reduction. If e-cigarette safety will be confirmed, however, the use of e-cigarettes alone may facilitate quitters remaining so.

Registration Number

NCT01785537.     

The relationship between chronic arsenic exposure and body measures among US adults: National Health and Nutrition Examination Survey 2009-2016

BackgroundCurrent research on the relationship between arsenic and body measures is inconclusive. We explored the relationship between arsenic and body measures in a large cohort representative of the United States population.MethodsData were analyzed from the 2009–2016 National Health and Nutrition Examination Survey (NHANES). We examined the relationship between quartiles of urinary arsenic metabolites and BMI as a continuous variable, BMI by obesity category, and waist circumference, using linear regression models without and with adjustment for gender, age, diabetes, hypertension, race, smoking, and alcohol use. A piecewise linear spline model with a knot at 4.26 μg/L/day, the urinary-flow-rate-adjusted dimethylarsinic acid median, modeled a non-linear relationship between dimethylarsinic acid and BMI.ResultsThe 6,848 participants were 51.4 % female, 13.6 % diabetic, 37.7 % hypertensive, 40.3 % white, 38 % obese, 20.3 % non-drinkers, and 56.0 % never-smokers. Compared to the lowest quartile, the highest quartile of daily excretion of all urinary arsenic metabolites was associated with lower BMI, waist circumference, and obesity except for dimethylarsinic acid in unadjusted and adjusted analyses. The same relationship was found with analysis of BMI and waist circumference as continuous variables. Urinary-flow-rate-adjusted dimethylarsinic acid was found to have a non-linear relationship with BMI with increasing excretion up to the median (4.78, 95 %CI = 0.30, 9.27; p = 0.04), and decreasing excretion beyond (-0.69, 95 %CI=-1.23, -0.16; p = 0.01).ConclusionWe found a strong inverse relationship between body measures and daily excretion of all urinary arsenic metabolites except dimethylarsinic acid, which had a positive relationship with BMI up to 4.26 μg/L/day, and an inverse relationship beyond it.     

Detection and Analysis of 12 Heavy Metals in Blood and Hair Sample from a General Population of Pearl River Delta Area

To detect the content of 12 heavy metals in blood and hair sample from a general population of Pearl River Delta area, and to analyze the influence of duration of residence, gender, age, smoking and drinking on the heavy metal content. Use inductively coupled plasma mass spectrometry to detect the content of 12 heavy metals lead (Pb), mercury (Hg), cadmium (Cd), aluminum (Al), arsenic (As), copper (Cu), chrome (Cr), manganese (Mn), nickel (Ni), zinc (Zn), tin (Sn) and antimony (Sb) in blood and hair samples of a total of 50 subjects from a general population, collected by multistage stratified cluster random sampling method. The geometric mean of heavy metal content in blood samples of general population (μg/L): blood aluminum 214.00; blood chrome 92.82; blood manganese 21.43; blood nickel 20.59; blood copper 0.67; blood zinc 11.50; blood arsenic 0.55; blood cadmium 2.45; blood tin 0.00; blood antimony 1.92; blood lead 158.84; and blood mercury 1.19. The geometric mean of heavy metal content in hair samples of general population (μg/g): hair aluminum is 84.65; hair chrome 0.00; hair manganese 2.44; hair nickel 0.61; hair copper 28.49; hair zinc 136.65; hair arsenic 0.75; hair cadmium 0.46; hair tin 1.04; hair antimony 0.05; hair lead 8.97; and hair mercury 0.69. Some heavy metals were correlated with duration of residence, gender, age, smoking and drinking. This was the first time that simultaneously detecting heavy metal content in blood and hair was used to analyze the internal heavy metal burden in resident population of Pearl River Delta area. These data can serve as reference for further research.     

Association between Smoking and Latent Tuberculosis in the U.S. Population: An Analysis of the National Health and Nutrition Examination Survey

Background

Evidence of an association between cigarette smoking and latent tuberculosis infection (LTBI) is based on studies in special populations and/or from high prevalence settings. We sought to evaluate the association between LTBI and smoking in a low prevalence TB setting using population-based data from the National Health and Nutrition Examination Survey (NHANES).

Methods

In 1999–2000, NHANES assessed LTBI (defined as a tuberculin skin test measurement ≥10 mm) in participants, and those ≥20 years of age were queried regarding their tobacco use and serum cotinine was measured. We evaluated the association of LTBI with self-reported smoking history and smoking intensity in multivariable logistic regression models that adjusted for known confounders (gender, age, birthplace, race/ethnicity, poverty, education, history of BCG vaccination, and history of household exposure to tuberculosis disease).

Results

Estimated LTBI prevalence was 5.3% among those ≥20 years of age. The LTBI prevalence among never smokers, current smokers, and former smokers was 4.1%, 6.6%, and 6.2%, respectively. In a multivariable model, current smoking was associated with LTBI (OR 1.8; 95% CI, 1.1–2.9). The association between smoking and LTBI was strongest for Mexican-American and black individuals. In multivariate analysis stratified by race/ethnicity, cigarette packs per day among Mexican-American smokers and cotinine levels among black smokers, were significantly associated with LTBI.

Conclusions

In the large, representative, population-based NHANES sample, smoking was independently associated with significantly increased risks of LTBI. In certain populations, a greater risk of LTBI corresponded with increased smoking exposure.     

Determination of Human Exposure to Lead and Cadmium: A WHO/UNEP Pilot Study

Abstract

In Stockholm, methods for measuring exposure to lead and cadmium from air, food and beverages were studied in 1988 in a group of 15 non-smoking women, as part of the WHO/UNEP HEAL programme. Airborne particles in the breathing zone air (24-hour samples), duplicate diets (24-hour samples), and faeces (all the stools produced) were collected during 7 consecutive days. Blood was sampled before and immediately after the study period. The results confirmed the need for personal monitoring in the assessment of human exposure to lead and cadmium via air and food. There is need for suitable equipment for 24-hour personal air monitoring. On average, dietary lead (26 μg day^?1, SD 7.9) contributed more than 80% of the total lead uptake, while dietary cadmium (8.5 μg day^?1 SD 2.1) contributed about 99% of the total cadmium uptake. Occasionally consumed foodstuffs with high levels of lead or cadmium seemed to be responsible for a large part of the total weekly intake of lead and cadmium. Fecal lead and cadmium were found to be useful indicators of the total amounts of these metals ingested. Due to the large day-to-day variation observed in the dietary intake of lead and cadmium, the sampling period for duplicate diets and faeces should be at least 5–6 days.     

Association Between Chronic Exposure to Tobacco Smoke and Accumulation of Toxic Metals in Hair Among Pregnant Women

Tobacco smoke contains various toxic heavy metals that individuals are exposed to when they smoke. Despite the presence of heavy metals in tobacco smoke, the relationship between smoking and the accumulation of toxic metals in pregnant women after long-term exposure remains under discussion. We examined the association between long-term exposure to tobacco smoke and the accumulation of toxic metals in the hair of female participants. Our study recruited 252 women from the Shanxi and Hebei provinces of Northern China; these participants were self-reported non-active smokers, and had previously delivered healthy babies without birth defects. Scalp hair was collected and analyzed for nicotine and cotinine and five potentially toxic metals (specifically, silver, chromium, cadmium, mercury, and lead). Our results showed significant positive correlations between cotinine and four metals, including silver (r?=?0.369, p?<?0.001), cadmium (r?=?0.185, p?<?0.01), mercury (r?=?0.161, p?<?0.05), and lead (r?=?0.243, p?<?0.001). Significant positive correlations were also found between nicotine and three metals—specifically silver (r?=?0.331, p?<?0.001), cadmium (r?=?0.176, p?<?0.01), and lead (r?=?0.316, p?<?0.001). A logistic regression model showed significant associations between cotinine and potentially toxic metals including mercury, silver, and lead (with or without adjusting for potential confounders). We thus conclude that long-term passive smoking could potentially increase the exposure level of toxic metals including lead, silver, and mercury in our study, which are especially harmful for pregnant women and their unborn fetus.     

Safety and efficacy of oral DMSA therapy for children with autism spectrum disorders: Part A - Medical results

Background

This study investigated the effect of oral dimercapto succinic acid (DMSA) therapy for children with autism spectrum disorders ages 3-8 years.

Methods

Phase 1 involved 65 children who received one round of DMSA (3 days). Participants who had high urinary excretion of toxic metals were selected to continue on to phase 2. In phase 2, 49 participants were randomly assigned in a double-blind design to receive an additional 6 rounds of either DMSA or placebo.

Results

DMSA greatly increased the excretion of lead, substantially increased excretion of tin and bismuth, and somewhat increased the excretion of thallium, mercury, antimony, and tungsten. There was some increase in urinary excretion of essential minerals, especially potassium and chromium. The Phase 1 single round of DMSA led to a dramatic normalization of RBC glutathione in almost all cases, and greatly improved abnormal platelet counts, suggesting a significant decrease in inflammation.

Conclusion

Overall, DMSA therapy seems to be reasonably safe, effective in removing several toxic metals (especially lead), dramatically effective in normalizing RBC glutathione, and effective in normalizing platelet counts. Only 1 round (3 days) was sufficient to improve glutathione and platelets. Additional rounds increased excretion of toxic metals.     

Association of urinary iodine concentration with prediabetes/diabetes in adults: Analysis of the NHANES 2005–2016

Background & AimsIodine is required for synthesizing thyroid hormones and regulating human metabolism. Iodine deficiency can lead to thyroid function abnormalities, which are closely associated with disturbances in glucose-insulin homeostasis. Research on the relationship between iodine and diabetes/prediabetes in adults was sparse and inconsistent. We assessed trends in urinary iodine concentration (UIC) and diabetes/prediabetes prevalence and focused on the association between iodine and diabetes/prediabetes among U.S. adults.MethodsWe analyzed the National Health and Nutrition Examination Survey (NHANES) data from the 2005–2016 cycles. Linear regression was employed to evaluate UIC and prediabetes/diabetes prevalence trends over time. Both multiple logistic regression and restricted cubic splines (RCS) were performed to evaluate the association of UIC with diabetes/prediabetes.ResultsA distinctly declining trend in median UIC and a significant increase in diabetes prevalence in U.S. adults from 2005 to 2016 were observed. The fourth quartile of UIC was associated with a 30% lower risk for prediabetes, compared with the first quartile (OR=0.70, 95% CI: 0.56–0.86, P_trend=0.001). However, UIC was not significantly associated with the prevalence of diabetes. The RCS model suggested a significant nonlinear relationship between UIC and the risk of diabetes (P for nonlinearity =0.0147). Stratification analysis showed that the negative associations of UIC with the risk of prediabetes were more pronounced in participants who were men, aged 46–65, overweight, light alcohol drinkers, and nonactive smokers.ConclusionsOverall, the adults’ median UIC in the U.S. population was a declining trend. However, diabetes prevalence increased significantly from 2005 to 2016. Higher UIC was associated with a lower risk of prediabetes.