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Introduction: Heavy metals such as Lead (Pb) and Mercury (Hg) can affect adipose tissue mass and function. Considering the high prevalence of exposure to heavy metals and obesity in Mexico, we aim to examine if exposure to Pb and Hg in adolescence can modify how fat is accumulated in early adulthood. Methods: This study included 100 participants from the ELEMENT cohort in Mexico. Adolescent Pb and Hg blood levels were determined at 14-16 years. Age- and sex-specific adolescent BMI Z-scores were calculated. At early adulthood (21-22 years), fat accumulation measurements were performed (abdominal, subcutaneous, visceral, hepatic, and pancreatic fat). Linear regression models with an interaction between adolescent BMI Z-score and Pb or Hg levels were run for each adulthood fat accumulation outcome with normal BMI as reference. Results: In adolescents with obesity compared to normal BMI, as Pb exposure increased, subcutaneous (p-interaction = 0.088) and visceral (p-interaction < 0.0001) fat accumulation increases. Meanwhile, Hg was associated with subcutaneous (p-interaction = 0.027) and abdominal (p-interaction = 0.022) fat deposition among adolescents with obesity. Conclusions: Heavy metal exposure in adolescence may alter how fat is accumulated in later periods of life.

Introduction: During adolescence, dairy product intake has shown conflicting associations with metabolic syndrome (MetS) components, which are risk factors for cardiovascular disease (CVD). This study aims to investigate the association between plasma fatty acids (FAs) C15:0, C17:0, and t-C16:1n-7, as biomarkers of dairy intake, with MetS and its components in Mexican adolescents. Methods: A sample of 311 participants from the Early Life Exposure in Mexico City to Environmental Toxicants (ELEMENT) cohort was included in this cross-sectional analysis. FA concentrations were measured in plasma as a percentage of total FA. We used quantile regression models stratified by sex to evaluate the association between FA quantiles and MetS components, adjusting for age, socioeconomic status (SES), sedentary behavior, BMI z-score, pubertal status, and energy intake. Results: We found significant associations between dairy biomarkers and the median of MetS variables. In females, t-C16:1n-7 was associated with a decrease of 2.97 cm in WC (Q4 vs. Q1; 95% CI: −5.79, −0.16). In males, C15:0 was associated with an increase of 5.84 mm/Hg in SBP (Q4 vs. Q1; CI: 1.82, 9.85). For HDL-C, we observed opposite associations by sex. C15:0 in males was associated with decreased HDL-C (Q3 vs. Q1: β = −4.23; 95% CI: −7.98, −0.48), while in females, C15:0 and t-C16:1n-7 were associated with increased HDL-C (Q3 vs. Q1: β = 4.75; 95% CI: 0.68, 8.82 and Q4 vs. Q1: β = 6.54; 95% CI: 2.01, 11.07), respectively. Additionally, in both sexes, different levels of C15:0, C17:0, and t-C16:1n-7 were associated with increased triglycerides (TG). Conclusion: Our results suggest that adolescent dairy intake may be associated in different directions with MetS components and that associations are sex-dependent. [ABSTRACT FROM AUTHOR]

Introduction: Heavy metals such as Lead (Pb) and Mercury (Hg) can affect adipose tissue mass and function. Considering the high prevalence of exposure to heavy metals and obesity in Mexico, we aim to examine if exposure to Pb and Hg in adolescence can modify how fat is accumulated in early adulthood. Methods: This study included 100 participants from the ELEMENT cohort in Mexico. Adolescent Pb and Hg blood levels were determined at 14–16 years. Age‐ and sex‐specific adolescent BMI Z‐scores were calculated. At early adulthood (21–22 years), fat accumulation measurements were performed (abdominal, subcutaneous, visceral, hepatic, and pancreatic fat). Linear regression models with an interaction between adolescent BMI Z‐score and Pb or Hg levels were run for each adulthood fat accumulation outcome with normal BMI as reference. Results: In adolescents with obesity compared to normal BMI, as Pb exposure increased, subcutaneous (p‐interaction = 0.088) and visceral (p‐interaction < 0.0001) fat accumulation increases. Meanwhile, Hg was associated with subcutaneous (p‐interaction = 0.027) and abdominal (p‐interaction = 0.022) fat deposition among adolescents with obesity. Conclusions: Heavy metal exposure in adolescence may alter how fat is accumulated in later periods of life. [ABSTRACT FROM AUTHOR]

We aimed to estimate vaccination coverage and factors associated in completing schemes in children under 5 years old between 2000 and 2018. A secondary analysis was carried out on five national health surveys between 2000 and 2018 in Mexico. The sample was 53,898 children under 5 years old, where 30% of missing vaccination information was imputed using chained equations. During this period two basic vaccination schemes (CBS) were identified. For each doses and vaccines of both schemes and completed CBS, the coverage was estimated using weighted logistic regression models. Additionally, the factors associated with incomplete schemes were reported. Between 2000 and 2018, the caretakers who did not show the vaccination card went from 13.8% to 45.6%. During this period, the estimated vaccination coverages did not exceed 95%, except for BCG and marginally the first doses of vaccines against pneumococcus, acellular pentavalent, and Sabin. In the same period, the CBS estimated coverage decreased steadily and was under 90%, except for children aged 6–11 months (92.6%; 91.5–93.7) in 2000. Not having health insurance stands out as an associated factor with incomplete vaccination schemes. In conclusion, the imputation allowed to recuperate information and obtain better data of vaccination coverage. The estimated vaccination coverage and CBS do not reach sufficient levels to guarantee herd immunity, hence innovative strategies to improve vaccination must be established in Mexico. [ABSTRACT FROM AUTHOR]

Aims: To identify the effect of unmet dental treatment needs and socioeconomic and sociodemographic variables on the patterns of dental visits in the presence of dental pain in 6- to 12-year-old Mexican schoolchildren. Methods: A case-control study included 379 patients that had a dental visit because of dental pain in the 12 months preceding this study and 1,137 controls. Mothers and/or guardians supplied sociodemographic, socioeconomic, and oral health-related information through a questionnaire. The profiles of unmet dental needs and of oral hygiene were ascertained by means of a standardized dental examination administered to participating children. Odds ratios (OR) and 95% confidence intervals (CIs) were calculated with logistic regression. Results: Higher unmet dental needs and lack of health insurance were associated with the experience of dental visits because of dental pain in the preceding 12 months. Boys who attended public schools had a 70% (95% CI = 1.29 to 2.23) higher probability of having had a dental visit in which dental pain was one of the main reasons for attendance, compared to boys attending private schools. The effect for girls was only 28% (95% CI = 1.10 to 1.50) higher for girls attending a public school, compared to girls attending private schools. Older children had a higher occurrence of dental visits because of dental pain than younger children. Conclusions: While higher unmet dental needs and lack of health insurance were strong predictors of having had dental visits because of dental pain in the preceding 12 months, some socioeconomic variables and sociodemographic variables modified these relationships. [ABSTRACT FROM AUTHOR]

Progress towards the Millennium Development Goal No. 5 was measured by an indicator that excluded women who died due to pregnancy and childbirth after 42 days from the date of delivery. These women suffered from what are defined as late deaths and sequelae-related deaths (O96 and O97 respectively, according to the International Classification of Diseases, 10th revision). Such deaths end up not being part of the numerator in the calculation of the Maternal Mortality Ratio (MMR), the indicator that governments and international agencies use for reporting. The issue is not trivial since these deaths account for a sizeable fraction of all maternal deaths in the world and show an upward trend over time in many countries. The aim of this study was to analyze empirical data on maternal deaths that occurred between 2010 and 2013 in Mexico, linking databases of the Deliberate Search and Reclassification of Maternal Deaths (BIRMM) and the Birth Information Subsystem (SINAC) of the Ministry of Health. Data were analyzed by negative binomial regression, survival analysis and multiple cause analysis. While the reported MMR decreased by 5% per year between 2010 and 2013, the MMR due to late and sequelae-related deaths doubled from 3.5 to 7 per 100,000 live-births in 2013 (p <0.01). A survival analysis of all maternal deaths revealed nothing particular around the 42 day threshold, other than the exclusion of 18% of women who died due to childbirth in 2013. The multiple cause analysis showed a strong association between the excluded deaths and obstetric causes. It is suggested to review the construction of the MMR to make it a more inclusive and dignified measurement of maternal mortality by including all deaths due to pregnancy and childbirth into the Maternal Death definition. [ABSTRACT FROM AUTHOR]

Background: Human milk is a potential source of lead exposure. Yet lactational transfer of lead from maternal blood into breast milk and its contribution to infant lead burden remains poorly understood. Objectives: We explored the dose-response relationships between maternal blood, plasma, and breast milk to better understand lactational transfer of lead from blood and plasma into milk and, ultimately, to the breastfeeding infant. Methods: We measured lead in 81 maternal blood, plasma, and breast milk samples at 1 month postpartum and in 60 infant blood samples at 3 months of age. Milk-to-plasma (M/P) lead ratios were calculated. Multivariate linear, piecewise, and generalized additive models were used to examine dose-response relationships between blood, plasma, and milk lead levels. Results: Maternal lead levels (mean ± SD) were as follows: blood: 7.7 ± 4.0 μg/dL; plasma: 0.1 ± 0.1 μg/L; milk: 0.8 ± 0.7 μg/L. The average M/P lead ratio was 7.7 (range, 0.6–39.8) with 97% of the ratios being > 1. The dose–response relationship between plasma lead and M/P ratio was nonlinear (empirical distribution function = 6.5, p = 0.0006) with the M/P ratio decreasing by 16.6 and 0.6 per 0.1 μg/L of plasma lead, respectively, below and above 0.1 μg/L plasma lead. Infant blood lead level (3.4 ± 2.2 μg/dL) increased by 1.8 μg/dL per 1 μg/L milk lead (p < 0.0001, R2 = 0.3). Conclusions: The M/P ratio for lead in humans is substantially higher than previously reported, and transfer of lead from plasma to milk may be higher at lower levels of plasma lead. Breast milk is an important determinant of lead burden among breastfeeding infants. [ABSTRACT FROM AUTHOR]

Objective: To compare the liking, flavor and texture of whole, partially defatted and defatted cow's milk using sensory tests. Materials and Methods: Children aged 6-16 years, living in indigenous boarding schools in the State of Hidalgo, Mexico, tested samples of whole, partially defatted and defatted cow's milk and answered a questionnaire that explored liking, flavor and texture through ad hoc designed scales. The differences in response proportions were analyzed by χ2 tests and multinomial logistic regression models. Results: Tests were completed by 165 children (79 girls and 86 boys). Rated by habitual consumers of whole, partially defatted and defatted milk, liking (70.6-77.8%, liked it very much), flavor (72.5-77.8%, very tasteful) and texture (41.3-54.9%, not creamy or watery) were better rated for defatted than for whole milk [liking (19.6-29.4%, p < 0.001, liked it very much), flavor (19.6-39.7%, p < 0.001, very tasty) and texture (27.5-39.2%, p < 0.05, not creamy or watery)]. The global preference was higher for defatted (74.5-81.0%) than for whole milk (6.3-15.7%, p < 0.001). Conclusions: Defatted milk (0.5%) can be introduced into public programs to reduce the saturated fat intake or control obesity in children older than 6 years in elementary schools. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Lead exposure in adults is associated with hypertension. Altered prenatal nutrition is associated with subsequent risks of adult hypertension, but little is known about whether prenatal exposure to toxicants, such as lead, may also confer such risks. Objectives: We investigated the relationship of prenatal lead exposure and blood pressure (BP) in 7- to 15-year-old boys and girls. Methods: We evaluated 457 mother-child pairs, originally recruited for an environmental birth cohort study between 1994 and 2003 in Mexico City, at a follow-up visit in 2008-2010. Prenatal lead exposure was assessed by measurement of maternal tibia and patella lead using in vivo K-shell X-ray fluorescence and cord blood lead using atomic absorption spectrometry. BP was measured by mercury sphygmomanometer with appropriate-size cuffs. Results: Adjusting for relevant covariates, maternal tibia lead was significantly associated with increases in systolic BP (SBP) and diastolic BP (DBP) in girls but not in boys (p-interaction with sex = 0.025 and 0.007 for SBP and DBP, respectively). Among girls, an interquartile range increase in tibia lead (13 µg/g) was associated with 2.11-mmHg [95% confidence interval (CI): 0.69, 3.52] and 1.60-mmHg (95% CI: 0.28, 2.91) increases in SBP and DBP, respectively. Neither patella nor cord lead was associated with child BP. Conclusions: Maternal tibia lead, which reflects cumulative environmental lead exposure and a source of exposure to the fetus, is a predisposing factor to higher BP in girls but not boys. Sex-specific adaptive responses to lead toxicity during early-life development may explain these differences. [ABSTRACT FROM AUTHOR]

Background: Rates of preterm birth have been rising over the past several decades. Factors contributing to this trend remain largely unclear, and exposure to environmental contaminants may play a role. Objective: We investigated the relationship between phthalate exposure and preterm birth. Methods: Within a large Mexican birth cohort study, we compared third-trimester urinary phthalate metabolite concentrations in 30 women who delivered preterm (< 37 weeks of gestation) with those of 30 controls (⩾ 37 weeks of gestation). Results: Concentrations of most of the metabolites were similar to those reported among U.S. females, although in the present study mono-n-butyl phthalate (MBP) concentrations were higher and monobenzyl phthalate (MBzP) concentrations lower. In a crude comparison before correcting for urinary dilution, geometric mean urinary concentrations were higher for the phthalate metabolites MBP, MBzP, mono(3-carboxylpropyl) phthalate, and four metabolites of di(2-ethylhexyl) phthalate among women who subsequently delivered preterm. These differences remained, but were somewhat lessened, after correction by specific gravity or creatinine. In multivariate logistic regression analysis adjusted for potential confounders, elevated odds of having phthalate metabolite concentrations above the median level were found. Conclusions: We found that phthalate exposure is prevalent among this group of pregnant women in Mexico and that some phthalates may be associated with preterm birth. [ABSTRACT FROM AUTHOR]

To contrast the sensitivity, specificity, and positive–negative predictive values between dental fluorosis prevalence scored on 28 (DF28) and on six permanent teeth (DF6), we undertook a cross-sectional study on 1,538 adolescents (12 and 15 years old) residing in Hidalgo State, Mexico, a naturally fluoridated (>0.7 ppm) area at an elevated altitude (>2,500 m above sea level). Dental fluorosis was scored using Deans modified index. Using the scores obtained for all teeth present (DF28) as a gold standard, we calculated the sensitivity, specificity, positive–negative predictive values, and receiver operating characteristic and concordance index pertaining to the scores based on six teeth (upper incisors and canines). DF28 fluorosis prevalence was 81.7%; based on DF6, it was 58.7% (23% difference). Among 12 year olds, the difference between DF28 and DF6 was 20.1% (84.5 vs. 64.4%); among 15 year olds, it was 25.4% (79.4 vs. 54%). Among girls, it was 23.2% (81.1 vs. 57.9%) and among boys, 22.8% (82.2 vs. 59.4%). The fluorosis community indices were 1.75 (DF28) and 1.11 (DF6). All positive predictive values reached 100% while negative predictive values were below 45%. Concordance between DF28 and DF6 was 53.9%, and kappa coefficient was 0.40. Partial scoring of fluorosis based on esthetically important permanent teeth underestimated prevalence, compared to full-mouth scoring. The decision to use an abridged Dean’s index protocol must take into account the number of teeth examined, and which specific teeth are examined, to appraise the benefit of reduced data collection effort against possible information loss. [ABSTRACT FROM AUTHOR]

Early life phthalates exposure has been associated with adverse respiratory outcomes. However, evidence linking prenatal phthalates exposure and childhood lung function has been inconclusive. Additionally, few studies have examined phthalates exposure as a mixture and explored sexually dimorphic associations. We aimed to investigate sex-specific associations of prenatal phthalates mixtures with childhood lung function using the PROGRESS cohort in Mexico (N = 476). Prenatal phthalate concentrations were measured in maternal urine collected during the 2nd and 3rd trimesters. Children's lung function was evaluated at ages 8–13 years. Individual associations were assessed using multivariable linear regression, and mixture associations were modeled using repeated holdout WQS regression and hierarchical BKMR; data was stratified by sex to explore sex-specific associations. We identified significant interactions between 2nd trimester phthalates mixture and sex on FEV 1 and FVC z-scores. Higher 2nd trimester phthalate concentrations were associated with higher FEV 1 (β = 0.054, 95 %CI: 0.005, 0.104) and FVC z-scores (β = 0.074, 95 % CI: 0.024, 0.124) in females and with lower measures in males (FEV 1 , β = −0.017, 95 %CI: −0.066, 0.026; FVC, β = −0.014, 95 %CI: −0.065, 0.030). This study indicates that prenatal exposure to phthalates is related to childhood lung function in a sex-specific manner. [Display omitted] • Prenatal phthalate mixture associated with childhood lung function in a sex-specific manner. • 2nd trimester phthalate mixture linked to higher FEV 1 and FVC z-scores in females. • 2nd trimester phthalate mixture associated with lower FEV 1 and FVC z-scores in males. • Repeated holdout WQS and BKMR used to assess phthalate mixture effects on lung function. [ABSTRACT FROM AUTHOR]

Focuses on Mexican workers in the United States. Reference to the United States/Mexican War in 1845-1848; Immigration of Mexicans to the United States during the Mexican Revolution of 1910 to 1917; History of the relation between Mexico and the United States.

Low-grade inflammation is a suggested mechanism in the development of metabolic syndrome (MetS), and diet could act as a regulator. Therefore, we hypothesized that the cumulative Dietary Inflammatory Index (DII®) exposure from diet during infancy through adulthood would be positively associated with the MetS and its components in young Mexican adults. One hundred participants from the Early Life Exposures in Mexico to Environmental Toxicants cohort were included in this analysis. The dietary inflammatory potential of the diet (without supplements) was assessed using 27 nutrients obtained from repeated food frequency questionnaires (1-22 years) using the DII, a validated score. The cumulative exposure of DII was constructed using the area under the curve (AUC of DII). The MetS was defined using the International Diabetes Federation criteria, and the Metabolic Syndrome Risk Z -score (MetRisk Z -score) was estimated. Linear regressions were conducted to assess the association between the AUC of DII with MetRisk Z- score and MetS components, adjusting for sex, socioeconomic status, smoking status, physical activity, birth weight, and body mass index. In adulthood, the mean age was 21.5 years, 54% were male, and 17% had MetS. Positive associations were found between AUC of DII with MetRisk Z- score (β =.12; 95% confidence interval [CI]: 0.03-0.22; P =.009) and systolic (β =.33; 95% CI: 0.05-0.61; P =.023) and diastolic blood pressure (β =.24; 95% CI: 0.01-0.47; P =.040). A cumulative proinflammatory diet from infancy through young adulthood is associated with higher MetRisk Z- scores as well as blood pressure. These findings may provide evidence for the implementation of anti-inflammatory diet interventions throughout early life for the prevention of cardiometabolic risk. [ABSTRACT FROM AUTHOR]

Background: Metal(oid)s have been cross-sectionally associated with lung function outcomes in childhood but there is limited data on their combined effects starting in utero. Child sex may further modify these effects., Objective: Examine associations between in utero and early life exposure to metals assessed via novel dentine biomarkers and childhood lung function and explore effect modification by child sex., Methods: Analyses included 291 children enrolled in the Programming Research in Obesity, Growth, Environment and Social Stressors (PROGRESS) study, a longitudinal birth cohort study in Mexico City. Weekly dentine levels of arsenic (As), cadmium (Cd), cobalt (Co), copper (Cu), manganese (Mn), nickel (Ni), and lead (Pb) were measured from 15 weeks pre-birth to 15 weeks post birth in deciduous children's teeth. Lung function was tested at ages 8-14 years and then modeled as age, height and sex adjusted z-scores. Associations were modeled using lagged weighted quantile sum (LWQS) regression to evaluate the potential for a time-varying mixture effect adjusting for maternal age and education at enrollment and exposure to environmental tobacco smoke in pregnancy. Models were also stratified by sex., Results: We identified a window of susceptibility at 12-15 weeks pre-birth in which the metal mixture was associated with lower FVC z-scores in children aged 8-14 years. Cd and Mn were the largest contributors to the mixture effect (70 %). There was also some evidence of effect modification by sex, in which the mean weights and weighted correlations over the identified window was more evident in males when compared to females. In the male stratum, Cd, Mn and additionally Pb also dominated the mixture association., Conclusions: Prenatal metal(oid) exposure was associated with lower lung function in childhood. These findings underscore the need to consider both mixtures and windows of susceptibility to fully elucidate effects of prenatal metal(oid) exposure on childhood lung function., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

From 2005 to 2019, the Mexican government financed cervical cancer treatment for individuals without social security insurance through Seguro Popular 's Fund for Protection against Catastrophic Health Expenses. To better understand the impact of this program on access to treatment, we estimated the cervical cancer treatment gap (the proportion of patients with cervical cancer in this population who did not receive treatment). To calculate the expected number of incident cervical cancer cases we used national surveys with information on insurance affiliation and incidence estimates from the Global Burden of Disease study. We used a national claims database to determine the number of cases whose treatment was financed by Seguro Popular . From 2006 to 2016, the national cervical cancer treatment gap changed from 0.61 (95% CI 0.59 to 0.62) to 0.45 (95% CI 0.43 to 0.48), with an average yearly reduction of -0.012 (95% CI -0.024 to -0.001). The gap was greater in states with higher levels of marginalization and in the youngest and oldest age groups. Although the cervical cancer treatment gap among individuals eligible for Seguro Popular decreased after the introduction of public financing for treatment, it remained high. Seguro Popular was eliminated in 2019; however, individuals without social security have continued to receive cancer care financed by the government in the same healthcare facilities. These results suggest that barriers to care persisted after the introduction of public financing for treatment. These barriers must be reduced to improve cervical cancer care in Mexico, particularly in states with high levels of marginalization.

Objective: Hispanic populations typically show a high prevalence of dyslipidemias, especially of low high-density lipoproteins (HDLs) or HDL cholesterol. Highly admixed populations are ideal groups to clarify the role of genetic ancestry on HDL concentrations, isolating it from that of other factors. The objective of this study was to estimate the association between Native American genetic ancestry and HDL-cholesterol levels independent of socioeconomic factors in a representative sample of the Mexican population., Methods: We used data from the Mexican National Health Survey 2000, analyzing 1647 subjects from whom stored DNA samples and HDL measurements were available. To estimate proportional genetic ancestry (Native American, African, and European), we used a 107 genetic ancestry informative marker panel with the software STRUCTURE. To estimate the association between genetic ancestry and low HDL levels, we fitted logistic regression models with the percentage of Native American genetic ancestry, in quartiles, as the main predictor., Results: Mean HDL levels were 38.9 mg/dL, with 62% of subjects having levels below 40 mg/dL. Participants had on average 53.6% Native American, 39% European, and 7.3% African genetic ancestry. Those in the fourth quartile of Native American genetic ancestry had 35% higher odds of having low HDL-cholesterol relative to those in the first quartile (odds ratio, 1.35; 95% confidence interval, 0.99-1.81) after adjustment for socioeconomic level and other covariates, although the association is clearly nonlinear., Conclusion: Native American genetic ancestry seems to play a small but distinct role in the development of low HDL cholesterol levels., (© 2020 Wiley Periodicals, Inc.)

Background: Lead is a neurotoxic metal potentially affecting the developing brain. Children are particularly susceptible since they can absorb between 50% and 100% of ingested lead. There is no safe level for lead, therefore preventing exposure is crucial. We previously reported a positive association between lead concentrations found in candy and concurrent blood lead levels in Mexican children. This first report garnered media and the general public's attention., Objective: To conduct a follow-up study to assess lead concentrations in candy brands that we previously reported with concentrations ≥0.1ppm the U.S. Food and Drug Administration's recommended maximum lead level in candy likely to be consumed frequently by small children., Methods: In 2018 we analyzed 50 additional candy samples. Lead concentrations were analyzed by an inductively coupled plasma mass spectrometer and lead content per candy unit was calculated., Findings: We found concentrations were typically low, with a marked decrease from prior levels (2008). Nevertheless two candy units had concentrations of 0.1 ppm of lead., Conclusions: Candy may have lead concentrations up to 0.1 ppm and 1.2 μg per unit. This is a concern because candies are exported and consumed in many countries worldwide potentially resulting in human exposure. Continued public health surveillance is needed to protect populations especially vulnerable to lead exposure, especially children., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2020 The Author(s).)

Purpose: The Early Life Exposure in Mexico to ENvironmental Toxicants (ELEMENT) Project is a mother-child pregnancy and birth cohort originally initiated in the mid-1990s to explore: (1) whether enhanced mobilisation of lead from maternal bone stores during pregnancy poses a risk to fetal and subsequent offspring neurodevelopment; and (2) whether maternal calcium supplementation during pregnancy and lactation can suppress bone lead mobilisation and mitigate the adverse effects of lead exposure on offspring health and development. Through utilisation of carefully archived biospecimens to measure other prenatal exposures, banking of DNA and rigorous measurement of a diverse array of outcomes, ELEMENT has since evolved into a major resource for research on early life exposures and developmental outcomes., Participants: n=1643 mother-child pairs sequentially recruited (between 1994 and 2003) during pregnancy or at delivery from maternity hospitals in Mexico City, Mexico., Findings to Date: Maternal bone (eg, patella, tibia) is an endogenous source for fetal lead exposure due to mobilisation of stored lead into circulation during pregnancy and lactation, leading to increased risk of miscarriage, low birth weight and smaller head circumference, and transfer of lead into breastmilk. Daily supplementation with 1200 mg of elemental calcium during pregnancy and lactation reduces lead resorption from maternal bone and thereby, levels of circulating lead. Beyond perinatal outcomes, early life exposure to lead is associated with neurocognitive deficits, behavioural disorders, higher blood pressure and lower weight in offspring during childhood. Some of these relationships were modified by dietary factors; genetic polymorphisms specific for iron, folate and lipid metabolism; and timing of exposure. Research has also expanded to include findings published on other toxicants such as those associated with personal care products and plastics (eg, phthalates, bisphenol A), other metals (eg, mercury, manganese, cadmium), pesticides (organophosphates) and fluoride; other biomarkers (eg, toxicant levels in plasma, hair and teeth); other outcomes (eg, sexual maturation, metabolic syndrome, dental caries); and identification of novel mechanisms via epigenetic and metabolomics profiling., Future Plans: As the ELEMENT mothers and children age, we plan to (1) continue studying the long-term consequences of toxicant exposure during the perinatal period on adolescent and young adult outcomes as well as outcomes related to the original ELEMENT mothers, such as their metabolic and bone health during perimenopause; and (2) follow the third generation of participants (children of the children) to study intergenerational effects of in utero exposures., Trial Registration Number: NCT00558623., Competing Interests: Competing interests: None., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Context: Early life cortisol plays an important role in bone, muscle, and fat mobilization processes, which could influence body composition, affecting anthropometric indicators such as weight and height., Objective: To explore the association between diurnal cortisol levels and growth indexes in children from 12 to 48 months of age., Design: This study includes data from 404 children from the Programming Research in Obesity, Growth, Environment and Social Stressors Mexican birth cohort. Cortisol was measured in eight saliva samples collected at four time points during the day (from wakeup to bedtime), over 2 days, when the child was either 12, 18, or 24 months old. Total daytime cortisol levels were calculated by averaging the area under the curve (AUC) for the 2 days. Height and weight were measured from 12 to 48 months of age. Growth indexes were constructed according to z scores following World Health Organization standards: weight-for-age z score (Z-WFA), height/length-for-age z score, weight-for-height/length z score (Z-WFH), and body mass index-for-age z score (Z-BMIFA). Mixed models were used to analyze the association between cortisol AUC quartiles and growth indexes., Results: Cortisol showed an inverted U-shaped association with the four growth indexes. Compared with the first quartile, all quartiles had a positive association with indexes that include weight, with the second quartile having the strongest association, resulting in an average change of β (95% CI) 0.38 (0.13-0.64) for Z-WFA, 0.36 (0.10-0.62) for Z-WFH, and 0.43 (0.17-0.69) for Z-BMIFA., Conclusions: Results suggest that early life daytime cortisol levels, as a reflection of hypothalamic-pituitary-adrenal axis development, might influence growth in early infancy.

Background: Cardiovascular disease in women often develops without conventional risk factors. Prenatal loss is a common pregnancy outcome that may result in physiological changes can increase the potential future risk of cardiovascular disease. Insufficient information exists regarding the impact of pregnancy loss on early markers of cardiovascular disease risk., Methods and Results: Cross-sectional analysis of 1767 disease-free women from the MTC (Mexican Teachers' Cohort) who had been pregnant was used to evaluate the relationship between pregnancy loss and carotid intima-media thickness (IMT). Participants responded to a questionnaire regarding their reproductive history, risk factors, and medical conditions. We defined pregnancy loss as history of miscarriage and/or stillbirth. Trained neurologists measured IMT using ultrasound. We log-transformed IMT and defined subclinical carotid atherosclerosis (SCA) as IMT ≥0.8 mm and/or plaque. We used multivariable linear and logistic regression models to assess the relation of pregnancy loss, IMT, and SCA. The mean age of participants was 49.8±5.1 years. The prevalence of pregnancy loss was 22%, and we observed SCA in 23% of participants. Comparing participants who reported a pregnancy loss and those who did not, the multivariable-adjusted odds ratio for SCA was 1.52 (95% confidence interval, 1.12-2.06). Women who experienced a stillbirth had 2.32 higher odds (95% confidence interval, 1.03-5.21) of SCA than those who did not. Mean IMT appeared to be higher in women who reported a pregnancy loss relative to those who did not; nevertheless, this was not statistically significant., Conclusions: Pregnancy loss could be linked to cardiovascular disease later in life. The key findings of our study await confirmation and further investigation of the potential underlying mechanisms for this association is required., (© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.)

Background: Ineffective management of obstetric emergencies contributes significantly to maternal and neonatal morbidity and mortality in Mexico. PRONTO (Programa de Rescate Obstétrico y Neonatal: Tratamiento Óptimo y Oportuno) is a highly-realistic, low-tech simulation-based obstetric and neonatal emergency training program. A pair-matched hospital-based controlled implementation trial was undertaken in three states in Mexico, with pre/post measurement of process indicators at intervention hospitals. This report assesses the impact of PRONTO simulation training on process indicators from the pre/post study design for process indicators., Methods: Data was collected in twelve intervention facilities on process indicators, including pre/post changes in knowledge and self-efficacy of obstetric emergencies and neonatal resuscitation, achievement of strategic planning goals established during training and changes in teamwork scores. Authors performed a longitudinal fixed-effects linear regression model to estimate changes in knowledge and self-efficacy and logistic regression to assess goal achievement., Results: A total of 450 professionals in interprofessional teams were trained. Significant increases in knowledge and self-efficacy were noted for both physicians and nurses (p <0.001- 0.009) in all domains. Teamwork scores improved and were maintained over a three month period. A mean of 58.8% strategic planning goals per team in each hospital were achieved. There was no association between high goal achievement and knowledge, self-efficacy, proportion of doctors or nurses in training, state, or teamwork score., Conclusions: These results suggest that PRONTO's highly realistic, locally appropriate simulation and team training in maternal and neonatal emergency care may be a promising avenue for optimizing emergency response and improving quality of facility-based obstetric and neonatal care in resource-limited settings., Trial Registration: NCT01477554.

Background: The Mexican government is currently implementing strategies to improve and expand comprehensive treatment for people living with HIV. Limited data, however, are available on the benefits obtained and costs incurred by these strategies., Objective: To estimate the effects of highly active antiretroviral therapy (HAART) on a cohort of people living with HIV and to estimate the cost of extending patients' lives., Methods: A survival analysis was used to follow a dynamic cohort of 797 people receiving AIDS treatment in Mexico from 1982 to 2006. The Kaplan-Meier method was applied to estimate the probability of survival for different lengths of time starting on the date of diagnosis. The Cox's proportional hazards regression model was used to assess differences in AIDS mortality by antiretroviral therapy regimen, age and sex., Results: The probability of survival after diagnosis without antiretroviral therapy (ART) was approximately 0.73 (95% CI 0.69-0.77) after the first year, 0.36 (95% CI 0.32-0.40) at 5 years, 0.28 (95% CI 0.24-0.33) at the tenth year, 0.26 (95% CI 0.21-0.31) at the fifteenth year and 0.22 (95% CI 0.14-0.30) thereafter. The results showed a longer life expectancy when patients took HAART (as opposed to monotherapy or dual therapy) from the beginning of their treatment. Results from the Cox model showed that those who started and continued on HAART were 7.1 (P < 0.01) times more likely to survive than those who received no treatment. Extending the length of life beyond 15 years after the initial diagnosis represents an accumulated cost of more than US$280,000.00 per individual.