RESUMO
BACKGROUND: The association of the built environment and the structural availability of services/amenities with adolescent birth rates (ABR) has been overlooked in Latin America. We investigated the association of the availability, and changes in the availability, of services/amenities with ABR in 92 Mexican cities. METHODS: We estimated ABR using data on live birth registration linked to municipality of residence at the time of birth from 2008-2017. The number of services/amenities were obtained from the National Statistical Directory of Economic Units in 2010, 2015, and 2020 and grouped as follows: education, health care, pharmacies, recreation, and on- and off-premises alcohol outlets. Data were linearly interpolated to obtain yearly estimates. We estimated densities per square km by municipality. We fitted negative binomial hybrid models, including a random intercept for municipality and city, and adjusted for other social environment variables. RESULTS: After adjustment a 1-unit increase in the density of recreation facilities, pharmacies, and off-premises alcohol outlets within municipalities was associated with a 5%, 4% and 12% decrease in ABR, respectively. Municipalities with higher density of education, recreational and health care facilities had a lower ABR; in contrast, municipalities with a higher density of on-premises alcohol experienced a higher ABR. CONCLUSION: Our findings highlight the importance of economic drivers and the need to invest in infrastructure, such as pharmacies, medical facilities, schools, and recreation areas and limit the availability of alcohol outlets to increase the impact of current adolescent pregnancy prevention programs.
Assuntos
Coeficiente de Natalidade , Parto , Feminino , Gravidez , Humanos , Adolescente , Cidades/epidemiologia , Etanol , EscolaridadeRESUMO
Objective: We investigated the association between the density of internal human migration, in the urban neighborhood, on frailty in the older adult population in Colombia. Methods: The data used in this study are from four Colombian population surveys. We analyzed 633 census tracts with a sample of 2,194 adults 60 years and over for frailty (measured using the Fried criteria). We considered the proportion of inhabitants in a census tract with a history of internal migration as the exposure variable considering three temporalities. For contextual forced migration, we identified two types: 5-year, and 1-year. Poisson multivariable regression models with two hierarchical levels (individual and census tracts) were estimated. Results: The prevalence of pre-fragile/frailty was 80.63% [CI 95%: 77.67, 83.28]. The prevalence ratio were significantly higher for the older adults who live in neighborhoods where a higher proportion of internal migrants reside. Conclusion: We conclude that older adults who lived in neighborhoods with a high proportion of internal migrants experience more frailty. Potential explanations are that neighborhoods with high internal migration could experience social (l increase in cultural heterogeneity, in the perception of insecurity, violence and physical conditions (pressure on local economies and services, leading elderly residents to compete for neighborhood resources), translated into social stress.
Assuntos
Fragilidade , Migrantes , Humanos , Idoso , Fragilidade/epidemiologia , Colômbia/epidemiologia , Características de Residência , Coleta de DadosRESUMO
Church-based stroke prevention programs for Hispanics are underutilized. The Stroke Health and Risk Education (SHARE) project, a multicomponent cluster-randomized trial, addressed key stroke risk factors among predominantly Mexican Americans in a Catholic Church setting. Process evaluation components (implementation, mechanisms of impact, and context) are described. Partner support promoted positive health behavior change. Motivational interviewing calls were perceived as helpful, however, barriers with telephone delivery were encountered. Intervention exposure was associated with theory constructs for targeted behaviors. We conclude that health behavior interventions to prevent stroke can be successfully implemented for Mexican Americans within a Catholic Church setting, with parish priest support.
Assuntos
Americanos Mexicanos , Acidente Vascular Cerebral , Catolicismo , Educação em Saúde , Hispânico ou Latino , Humanos , Acidente Vascular Cerebral/prevenção & controleRESUMO
Background: Evidence suggests exposure to endocrine-disrupting chemicals (EDCs) can influence Metabolic Syndrome (MetS) risk in adults, but it is unclear if EDCs impact women during midlife. We examined if EDCs measured in adult women were predictive of MetS and its components 9 years later. Methods: We measured urinary phthalate metabolites, phenols, and parabens collected in 2008 among 73 females from the ELEMENT study. MetS and its components (Abdominal Obesity, Hypertriglyceridemia, Cholesterolemia, Hypertension, and Hyperglycemia) were assessed in 2017. We regressed log-transformed EDC concentrations on MetS and MetS components using logistic regression, adjusting for age and physical activity. Results: At follow-up, the mean (SD) age was 46.6 (6.3) years; the prevalence of MetS was 34.3%. Sum of dibutyl phthalate metabolites (ΣDBP), monobenzyl phthalate (MBzP), and monoethyl phthalate (MEP) were associated with an increased odds of hypertriglyceridemia. 2,5-dichlorophenol (2,5 DCP) and 2,4-dichlorophenol (2,4 DCP) were associated with increased odds of hypertriglyceridemia. The odds of hypertension were 4.18 (95% CI: 0.98, 17.7, p < 0.10) and 3.77 (95% CI: 0.76, 18.62, p < 0.10) times higher for every IQR increase in MCOP and propyl paraben, respectively. The odds of hyperglycemia were 0.46 (95% CI: 0.18, 1.17 p < 0.10) times lower for every IQR increase in the sum of di-2-ethylhexyl phthalate metabolites (ΣDEHP), and the odds of abdominal obesity were 0.70 (95% CI: 0.40, 1.21, p < 0.10) lower for every IQR increase in the concentration of triclosan. Conclusion: We found EDCs measured in 2008 were marginally predictive of hypertriglyceridemia and hypertension 9 years later. Results suggest that lower exposure to certain toxicants was related to lower markers of metabolic risk among midlife women.
Assuntos
Síndrome Metabólica , Parabenos , Adulto , Feminino , Humanos , Síndrome Metabólica/induzido quimicamente , México/epidemiologia , Pessoa de Meia-Idade , Parabenos/efeitos adversos , Fenóis/efeitos adversos , Ácidos FtálicosRESUMO
The prevalence of Attention Deficit/Hyperactivity Disorder (ADHD) has been increasing. Research suggests that exposure to endocrine disrupting chemicals such as phthalates may play a role, but studies of in utero phthalate exposure and ADHD-related symptoms beyond early childhood are limited. We investigated associations between measures of in utero phthalate exposure and ADHD symptoms, such as inattention and impulsivity, in childhood (age 6-11 years, n = 221) and in adolescence (age 9-18 years, n = 200), as well as cross-sectional relationships between phthalate exposure and ADHD symptoms in adolescence (n = 491) among participants in the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohort. Women provided urine samples up to three times during pregnancy and adolescents provided a urine sample at 9-18 years of age for phthalate metabolite measurement. We administered the Conners' Continuous Performance Test (CPT) when children were age 6-11 years and again at 9-18 years of age. We used multivariable linear regression to examine associations between the geometric mean of phthalate metabolite levels across pregnancy and CPT scores in childhood or adolescence separately, adjusting for age, years schooling (at 9-18 only), maternal education, and specific gravity. Although average in utero phthalate concentrations were not associated with CPT scores in childhood, interquartile range (IQR) increases of in utero MBzP, MCPP, and MBP were associated with 4.2%, 4.7%, and 4.5% (p < 0.05) higher Omissions scores in adolescence, respectively, indicating higher inattention. In utero MiBP levels were also associated with higher Inter-Stimulus Interval (ISI) and Variability scores (5.4% and 5.5% per IQR, p < 0.05) in adolescence. In addition, urinary DEHP metabolite levels during adolescence were cross-sectionally associated with poorer scores on several CPT indices indicating greater inattention. These findings suggest that in utero phthalate exposure may have adverse effects on attention, but these effects may not appear until adolescence, a period of extensive neurodevelopment. Future research investigating the long-term effects of in utero phthalate exposure on attention and ADHD in adolescence, as well as identification of potential mechanisms involved, is needed.
Assuntos
Disruptores Endócrinos , Poluentes Ambientais , Ácidos Ftálicos , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/toxicidade , Feminino , Humanos , México , Ácidos Ftálicos/toxicidade , GravidezRESUMO
BACKGROUND: Endocrine disrupting chemicals (EDCs) such as metals have been reported to alter circulating reproductive hormone concentrations and pubertal development in animals. However, the relationship has rarely been investigated among humans, with the exception of heavy metals, such as Pb and Cd. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone concentrations and sexual maturation and progression among boys from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts. METHODS: Our analysis included 118 pregnant women and their male children from the ELEMENT study. Essential and non-essential metals were measured in urine collected from the mothers during the third trimester of pregnancy and their male children at 8-14 years. Reproductive hormone concentrations [serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG)] were measured in blood samples from the children at 8-14 years. We also assessed Tanner stages for sexual maturation (genital, pubic hair development, and testicular volume), at two time points (8-14, 10-18 years). We used linear regression to independently examine urinary metal concentrations in relation to each peripubertal reproductive hormones adjusting for child age and BMI. Generalized estimation equations (GEEs) were used to evaluate the association of in utero and peripubertal metal exposures with sexual maturation and progression during follow-up based on Tanner staging and testicular volume. RESULTS: In utero and prepubertal concentrations of some urinary metals were associated with increased concentrations of peripubertal reproductive hormones, especially non-essential metal(loid)s As and Cd (in utero), and Ba (peripubertal) as well as essential metal Mo (in utero) in association with testosterone. More advanced pubic hair developmental stage and higher testicular volume at the early teen visit was observed for boys with higher non-essential metal concentrations, including in utero Al and peripubertal Ba, and essential metal Zn concentration (peripubertal). These metals were also associated with slower pubertal progression between the two visits. CONCLUSION: These findings suggest that male reproductive development may be associated with both essential and non-essential metal exposure during in utero and peripubertal windows.
Assuntos
Arsênio/urina , Poluentes Ambientais/urina , Exposição Materna , Metais/urina , Efeitos Tardios da Exposição Pré-Natal , Maturidade Sexual , Adolescente , Adulto , Criança , Cidades , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Feminino , Humanos , Inibinas/sangue , Masculino , Troca Materno-Fetal , México , Gravidez , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue , Adulto JovemRESUMO
BACKGROUND: Particulate matter ≤10 µm in aerodynamic diameter (PM10) and diet quality are risk factors for systemic inflammation, which is associated with preterm birth (PTB). PM10 and a pro-inflammatory diet (assessed by the Dietary Inflammatory Index [DII®]) have been individually evaluated as causes of PTB and differences by offspring sex have been reported for the DII. However, additional studies are needed to evaluate joint effects of these associations to inform intervention efforts. OBJECTIVES: To evaluate the independent and joint effects of PM10 and energy-adjusted DII (E-DII) on PTB risks. METHODS: PM10 estimates were generated from daily citywide averages for 1216 pregnant women from three subcohorts of the Early Life Exposures in Mexico to Environmental Toxicants study using data from the Mexico City Outdoor Air Monitoring Network. Among a subset of participants (N = 620), E-DII scores were calculated using a validated food frequency questionnaire. Cox Proportional Hazards models were run for select periods during pregnancy and entire pregnancy averages for E-DII and PM10. We assessed for potential non-linear associations using natural splines. RESULTS: In adjusted models, PM10 exposure was associated with increased risks of PTB for a range of values (58-72 µg/m3) during the second trimester, while negative associations were seen during the second (≥74 µg/m3) and third trimesters (55-65 µg/m3). Analyses conducted using distributed lag models for periods closer to delivery (max lag = 90) did not show negative associations between PM10 exposure and preterm birth, and indeed positive significant associations were observed (estimates and figures). E-DII was not associated with PTB and there was no evidence of effect modification by infant sex. There was no evidence of interaction between PM10 and E-DII and the risk of preterm birth. DISCUSSION: Associations between PM10 and PTB in Mexico City varied over time and across levels of PM10. Our findings of negative associations in the second and third trimesters, which are contrary to the hypothesized relationship between PM10 and PTB, may be due to a number of factors, including live birth bias and the exposure period evaluated. Differences in results for the periods evaluated suggest that PM10 from shorter exposure windows may play a more proximal role in initiating preterm labor.
Assuntos
Poluentes Atmosféricos , Poluição do Ar , Nascimento Prematuro , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Dieta/efeitos adversos , Exposição Dietética , Feminino , Humanos , Lactente , Recém-Nascido , Exposição Materna/efeitos adversos , México/epidemiologia , Material Particulado/análise , Material Particulado/toxicidade , Gravidez , Nascimento Prematuro/induzido quimicamente , Nascimento Prematuro/epidemiologiaRESUMO
Background: The postpartum period may be a vulnerable life stage for a woman's cardiometabolic health. We examined associations of exposure to common endocrine-disrupting chemicals (EDCs) during pregnancy with weight from delivery through 1 year postpartum among 199 women in Mexico City. Materials and Methods: During each trimester of pregnancy, we collected a urine sample to assay bisphenol A (BPA), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), monobenzyl phthalate (MBzP), mono-3-carboxypropyl phthalate (MCPP), mono-2-ethyl-5-carboxypentyl phthalate (MECPP), mono-2-ethyl-5-hydroxyhexyl phthalate (MEHHP), mono-2-ethylhexyl phthalate (MEHP), mono-2-ethyl-5-oxohexyl phthalate (MEOHP), and monoethyl phthalate (MEP). We calculated summary scores for di-2-ethylhexyl phthalate metabolites (ΣDEHP) and dibutyl phthalate metabolites (ΣDBP). We calculated the geometric mean of each EDC across pregnancy for use in the analysis. At delivery and three additional times during the first year postpartum, we measured the women's weight. We used mixed-effects linear regression models to estimate associations of each EDC with weight at delivery (kg) and weight change (kg/year) from delivery through 1 year postpartum. Covariates included urinary specific gravity, maternal age, parity, height, first trimester body mass index, and gestational age at enrollment. Results: Mean ± standard deviation weight change during the first postpartum year was -0.49 ± 4.04 kg. The EDCs were inversely associated with weight at delivery, but positively associated with weight change through 1 year postpartum. For example, each interquartile range of urinary ΣDEHP corresponded with 1.38 (95% confidence interval: 0.44-2.33) kg lower weight at delivery and 1.01 (0.41--1.61) kg/year slower rate of weight loss. We observed similar associations for other EDCs. Conclusions: Prenatal exposure to EDCs is associated with lower weight at delivery, but slower rate of weight loss through the first postpartum year.
Assuntos
Disruptores Endócrinos/efeitos adversos , Exposição Ambiental , Poluentes Ambientais/efeitos adversos , Ganho de Peso na Gestação , Estudos de Coortes , Disruptores Endócrinos/urina , Poluentes Ambientais/urina , Feminino , Humanos , México/epidemiologia , Período Pós-Parto , GravidezRESUMO
Although the isolated effects of several specific nutrients have been examined, little is known about the relationship between overall maternal diet during pregnancy and fetal development and growth. This study evaluates the association between maternal diet and low birthweight (LBW) in 660 pregnant women from the Pregnancy Research on Inflammation, Nutrition,& City Environment: Systematic Analyses (PRINCESA) cohort in Mexico City. Using prior day dietary intake reported at multiple prenatal visits, diet was assessed prospectively using a priori (Maternal Diet Quality Score [MDQS]) and a posteriori (dietary patterns extracted by factor analysis) approaches. The association between maternal diet and LBW was investigated by logistic regression, controlling for confounders. Adherence to recommended guidelines (higher MDQS) was associated with a reduced risk of LBW (OR, 0.22; 95% confidence interval [0.06, 0.75], P < .05, N = 49) compared with the lowest adherence category (reference group), controlling for maternal age, education, height, marital status, pre-pregnancy body mass index, parity, energy intake, gestational weight gain, and preterm versus term birth; a posteriori dietary patterns were not associated with LBW risk. Higher adherence to MDQS was associated with a lower risk of having an LBW baby in this sample. Our results support the role of advocating a healthy overall diet, versus individual foods or nutrients, in preventing LBW.
Assuntos
Dieta/métodos , Desenvolvimento Fetal , Recém-Nascido de Baixo Peso , Fenômenos Fisiológicos da Nutrição Materna , Política Nutricional , Adulto , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , México , Gravidez , Estudos Prospectivos , Adulto JovemRESUMO
Phthalates are endocrine disrupting compounds commonly found in consumer products, exposure to which may influence reproductive maturation. Effects from exposure in utero on the onset and progression of sexual development are understudied. We examined longitudinal associations between gestational phthalate exposure and sexual maturation at two points in adolescence (8-14, 9-18 years). Gestational exposure was quantified using the geometric mean of 3 trimester-specific urinary phthalate metabolite measurements. Sexual maturation was assessed using Tanner stages and menarche onset for girls and Tanner stages and testicular volume for boys. Generalized estimating equations for correlated ordinal multinomial responses were used to model relationships between phthalates and odds of transitioning to the next Tanner stage, while generalized additive (GA) mixed models were used to assess the odds of menarche. All models were adjusted for child age (centered around the mean), BMI z-score, change in BMI between visits, time (years) between visits (ΔT), and interactions between ΔT and mean-centered child age and the natural log of exposure metabolite concentration. Among girls, a doubling of gestational MBzP concentrations was associated with increased odds of being at a higher Tanner stage for breast development at 8-14 years (OR = 4.62; 95% CI: 1.38, 15.5), but with slower progression of breast development over the follow-up period (OR = 0.65 per year; 95% CI: 0.46, 0.92) after adjustment for child age and BMI z-score. Similar results were found for ∑DEHP levels and breast development. In boys, a doubling of gestational MBP concentrations was associated with lower odds of being at a higher Tanner stage for pubic hair growth at 8-14 years (OR = 0.37; 95% CI: 0.14, 0.95) but with faster progression (OR: 1.28; 95% CI: 0.97, 1.69). These results indicate that gestational phthalate exposures may impact the onset and progression of sexual development, and that these relationships differ between boys and girls.
Assuntos
Ácidos Ftálicos , Maturidade Sexual , Adolescente , Criança , Cidades , Feminino , Humanos , Masculino , México , Fenóis , Ácidos Ftálicos/toxicidade , Maturidade Sexual/efeitos dos fármacosRESUMO
CONTEXT: Several cross-sectional studies have assessed the association of lead exposure with type 2 diabetes and cardiometabolic risk factors in adults; however, studies of such associations in childhood are rare. OBJECTIVE: We assessed the prospective associations of prenatal exposure to lead with type 2 diabetes and cardiometabolic risk factors in children. DESIGN: The Early Life Exposure in Mexico to Environmental Toxicants is a birth cohort study of pregnant women and their offspring. SETTING: Public hospitals in Mexico City. PATIENTS OR OTHER PARTICIPANTS: Women were recruited during pregnancy; their offspring were recruited for a follow-up visit at age 10 to 18 years (n = 369). MAIN OUTCOME MEASURES: We measured fasting serum markers of type 2 diabetes and cardiometabolic risk factors in children, including fasting glucose, insulin, and lipids. The index of insulin resistance was calculated. RESULTS: The geometric mean of maternal blood lead levels (BLLs) during pregnancy was 4.3 µg/dL (95% confidence interval [CI]): 4.0-4.6 µg/dL) in the entire sample. In boys, those with maternal BLLs ≥ 5 µg/dL (compared with those with BLLs < 5 µg/dL) had significantly lower z scores for total cholesterol (ß = -0.41, 95% CI: -0.71, -0.12), high-density lipoprotein cholesterol (ß = -0.32, 95% CI: -0.59, -0.05), and low-density lipoprotein cholesterol (ß = -0.52, 95% CI: -0.81, -0.22), adjusting for covariates. No associations were detected in girls. CONCLUSIONS: In our study, we found that higher prenatal exposure to lead was associated with lower levels of cholesterol in children following a sex-specific pattern. Further studies with a larger sample size that examine whether sex is a potential modifier are needed to confirm our findings.
Assuntos
Doenças Cardiovasculares/etiologia , Filho de Pais com Deficiência , Diabetes Mellitus Tipo 2 , Intoxicação por Chumbo , Doenças Metabólicas/etiologia , Gravidez em Diabéticas , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adolescente , Adulto , Doenças Cardiovasculares/epidemiologia , Criança , Filho de Pais com Deficiência/estatística & dados numéricos , Estudos de Coortes , Estudos Transversais , Feminino , Seguimentos , Humanos , Recém-Nascido , Chumbo/análise , Chumbo/sangue , Chumbo/toxicidade , Masculino , Doenças Metabólicas/epidemiologia , México/epidemiologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: Several animal studies have suggested that fluoride exposure may increase the levels of cardiometabolic risk factors, but little is known about whether fluoride exposure is associated with such risk in humans. OBJECTIVES: We examined the cross-sectional association between peripubertal exposure to fluoride and markers of cardiometabolic risk in 280 girls and 256 boys at age 10-18â¯years living in Mexico City. METHODS: We measured plasma fluoride concentration using a microdiffusion method. We collected data on anthropometry including BMI, waist circumference (WC) and trunk fat percentage. We measured serum markers of cardiometabolic risk, including fasting glucose, insulin and lipids. All the indicators of outcome were converted to age- and sex-specific z-scores. We also calculated a summary cardiometabolic risk score for each participant. Multivariable linear regression models were used to examine these associations. RESULTS: The geometric mean (95% confidence interval (CI)) of plasma fluoride was 0.21⯵mol/L (0.20, 0.23⯵mol/L) in the total sample. In girls, plasma fluoride concentrations were associated with higher z-scores for all the individual markers (except for lipids) and for the combined cardiometabolic risk score (risk score: ßâ¯=â¯1.28, 95% CI: 0.57-2.00, p-sex interactionâ¯=â¯0.02)), adjusting for covariates. No associations were found in boys. CONCLUSIONS: We found that higher peripubertal fluoride exposure at the levels observed in this study population was significantly associated with increased levels of cardiometabolic risk factors in Mexican girls but not boys. Future studies with a longitudinal design are needed to confirm our findings and further elucidate the role of fluoride in cardiometabolic risk.
Assuntos
Doenças Cardiovasculares/epidemiologia , Fluoretos/efeitos adversos , Adiposidade , Adolescente , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Fluoretos/sangue , Humanos , Masculino , México/epidemiologia , Fatores de Risco , Fatores Sexuais , Circunferência da CinturaRESUMO
There is increasing evidence that several metals are endocrine disrupting chemicals (EDCs). In utero development and adolescence are critical windows of susceptibility to EDC exposure. With the exception of a few heavy metals, few human studies have evaluated the impact of metal exposure on pubertal development. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone levels and sexual maturation and progression among girls from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts. We measured urinary concentrations of aluminum (Al), arsenic (As), barium (Ba), cadmium (Cd), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), antimony (Sb), selenium (Se), and zinc (Zn) in samples collected from women during their third trimester of pregnancy and from their female children at 8-13 years (nâ¯=â¯132). We measured serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG) at age 8-13, and assessed Tanner stages for sexual maturation (breast, pubic hair development, and menarche status), at two time points (8-13, 14-18 years). We used linear regression to independently examine in utero and peripubertal metal concentrations as predictors of peripubertal hormones. In a longitudinal analysis using generalized estimation equations, we evaluated Tanner stage and menarche progression in relation to individual in utero and peripubertal metal concentrations. We found that higher in utero Zn was associated with increased inhibin B. Several metals at 8-13 years were associated with higher DHEA-S and estradiol, while Ni was positively but Cu was negatively associated with testosterone. In utero Ni, Al, and Cd were associated with slower progression of breast development after adjustment for child age and BMI z-score. For example, an IQR increase in in utero Al exposure was associated with 0.82 times lower odds of progressing to a higher Tanner stage for breast development per year (95% CI: 0.68, 0.99). Peripubertal concentrations of Ba and Al were also associated with being at a higher pubic hair Tanner stage and menarche at 8-13, but lower odds of progressing to the next stage at 14-18 years. We used Bayesian kernel machine regression (BKMR) to model the joint effect of multiple metals while accounting for correlated exposures, as well as potential non-linear relationships between metals and outcomes of interest, which yielded results similar to individual analyses. These findings suggest that female reproductive development may be vulnerable to the effects of metal exposure, and using both Tanner stages and hormone levels may provide clues about underlying mechanisms in two sensitive periods of development.
Assuntos
Disruptores Endócrinos/efeitos adversos , Hormônios Esteroides Gonadais/sangue , Metais Pesados/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Maturidade Sexual , Adolescente , Teorema de Bayes , Criança , Cidades , Sulfato de Desidroepiandrosterona/sangue , Disruptores Endócrinos/urina , Estradiol/sangue , Feminino , Humanos , Inibinas/sangue , Metais Pesados/urina , México , Gravidez , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangueRESUMO
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.
Assuntos
Osso e Ossos/metabolismo , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/efeitos adversos , Chumbo/efeitos adversos , Chumbo/metabolismo , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Adulto , Fatores Etários , Feminino , Humanos , Recém-Nascido , Masculino , México , Gravidez , Adulto JovemRESUMO
Alterations in pubertal timing have been associated with long-term health outcomes. While a few reports have shown that dietary intake of selenium is associated with fertility and testosterone levels in men, no human studies have considered the association between selenium and pubertal development in children. We examined the cross-sectional association of childhood dietary intake of selenium with pubertal development among 274 girls and 245 boys aged 10-18 years in Mexico City. Multiple logistic and ordinal regression models were used to capture the association between energy-adjusted selenium intake (below Recommended Dietary Allowance (RDA) vs. above RDA) and stages of sexual maturity in children, adjusted for covariates. We found that boys with consumption of selenium below the RDA had lower odds of a higher stage for pubic hair growth (odds ratio (OR) = 0.51, 95% confidence interval (95% CI): 0.27-0.97) and genital development (OR = 0.53, 95% CI: 0.28-0.99) as well as a lower probability of having matured testicular volume (OR = 0.37, 95% CI: 0.15-0.88) compared with boys who had adequate daily dietary intake of selenium (above RDA). No associations were found in girls. According to our results, it is possible that inadequate consumption of selenium may be associated with later pubertal development in boys, suggesting a sex-specific pattern. Future work with a larger sample size and measures of selenium biomarkers is needed to confirm our findings and improve understanding of the role of this mineral in children's sexual development.
Assuntos
Dieta , Puberdade/efeitos dos fármacos , Puberdade/fisiologia , Selênio/administração & dosagem , Maturidade Sexual/efeitos dos fármacos , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Masculino , México , Recomendações Nutricionais , Selênio/deficiência , Fatores Sexuais , Maturidade Sexual/fisiologiaRESUMO
Phthalates are a class of endocrine disrupting chemicals with near ubiquitous exposure to populations around the world. Phthalates have been associated with children's adiposity in previous studies, though discrepancies exist across studies that may be due to timing of exposure or outcome assessment and population differences (i.e., genetics, other confounders). DNA methylation, an epigenetic modification involved in gene regulation, may mediate the effects of early life phthalate exposures on health outcomes. This study aims to evaluate the mediating effect of DNA methylation at growth-related genes on the association between phthalate exposure and repeat measures of adiposity (BMI-for-age z-score, waist circumference, and skinfolds thickness) in Mexican children. Urinary phthalate metabolite concentrations were quantified in mothers at each of the three trimesters of pregnancy and in children at the first peri-adolescent study visit. Blood leukocyte DNA methylation at H19 and HSD11B2 was quantified during the first peri-adolescent visit, and adiposity was measured at the first visit and again ~3 years later among participants (n = 109 boys, 114 girls) from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) project. Associations between phthalates or DNA methylation and repeat outcome measures were assessed separately in boys and girls using generalized estimating equation models including covariates (urinary specific gravity, maternal education, and child's age). Sobel tests were used to assess DNA methylation as a mediator in models adjusting for the same covariates. Associations between phthalates and adiposity varied by phthalate and timing of exposure. Early gestation MBP, MIBP, and MBzP were associated with adiposity among girls. For example, among girls first trimester maternal urine concentrations of MIBP were associated with increases in skinfold thickness, BMI-for-age, and waist circumference (p < 0.01). Second trimester and adolescent MBzP were associated with adiposity among boys in opposite directions. In girls, H19 methylation was positively associated with skinfold thickness. No significant mediation of phthalate exposure on adiposity by DNA methylation of H19 or HSD11B2 was observed (Sobel p > 0.05). However, the mediation analysis was underpowered to detect small to medium effect sizes, and the role of DNA methylation as a mediator between phthalates and outcomes merits further study.
RESUMO
BACKGROUND: Prenatal and early childhood lead exposures have been associated with reduced weight in infants and young children, while studies that have examined such associations in children during peripubescence are rare. OBJECTIVES: We investigated the associations of prenatal and early-life exposure to lead with indices of adiposity in peripubertal children living in Mexico City. METHODS: Maternal bone lead (as a proxy for cumulative fetal exposure) was assessed at 1 month postpartum. Blood samples were obtained from children annually from 1 to 4 years. Multivariable linear regression models were used to examine the association between each lead biomarker and BMI z-score, waist circumference, sum of skinfolds and body fat percentage in 248 children aged 8-16 years. RESULTS: After adjusting for covariates, maternal patella lead was associated with lower child BMI z-score (ßâ¯=â¯-0.02, 95% CI: 0.03, -0.01, pâ¯=â¯0.004), waist circumference (ßâ¯=â¯-0.12â¯cm, 95% CI: 0.22, -0.03, pâ¯=â¯0.01), sum of skinfolds (ßâ¯=â¯-0.29â¯mm, 95% CI: 0.50, -0.08, pâ¯=â¯0.007) and body fat percentage (ßâ¯=â¯-0.09%, 95% CI: 0.17, -0.01, pâ¯=â¯0.03). No significant associations were detected from the postnatal exposure period. CONCLUSIONS: We observed a significant and inverse association of prenatal lead exposure with body composition in Mexican children, suggesting the potential role of early lead exposure in the fetal programming of child growth. Further research on the biological mechanisms underlying these associations is needed.
Assuntos
Adiposidade , Poluentes Ambientais/análise , Chumbo/análise , Exposição Materna , Efeitos Tardios da Exposição Pré-Natal , Adolescente , Adulto , Monitoramento Biológico , Criança , Cidades , Feminino , Humanos , Masculino , Troca Materno-Fetal , México , Patela/química , Gravidez , Tíbia/química , Adulto JovemRESUMO
OBJECTIVE: The aims of this study were to characterize, among pregnant Mexican women, gestational weight gain (GWG) trajectories; assess associations of maternal dietary quality score (MDQS) with GWG during early-mid pregnancy, middle pregnancy, late pregnancy, and prolonged pregnancy; and evaluate the association between MDQS and adequacy of GWG, throughout pregnancy. We hypothesized that higher MDQS adherence is protective against insufficient or excessive GWG across pregnancy and that the association between MDQS adherence and GWG would vary by prepregnancy body mass index (BMI) category. METHODS: We analyzed data from 660 pregnant women participating in the PRINCESA (Pregnancy Research on Inflammation, Nutrition and City Environments: Systematic Analyses) cohort in Mexico City, 2009 to 2014. Repeated measures of dietary intake and mother's weight were obtained during pregnancy. Individual GWG trajectories were modeled in a multilevel regression framework. Associations between MDQS (low, medium, and high adherence) and GWG were investigated using mixed-effect regression models with linear splines. RESULTS: Women with prepregnancy BMI of ≥30 kg/m2 had a slower rate of GWG (RGWG) compared with other categories. A higher adherence to MDQS was protective against an insufficient (odds ratio [OR], 0.63; 95% confidence interval [CI], 0.42-0.95; Pâ¯=â¯0.03) and an excessive RGWG (OR, 0.62; 95% CI, 0.41-0.94; Pâ¯=â¯0.03) throughout pregnancy, adjusting for prepregnancy BMI, energy intake, maternal age, educational level, parity, fetal sex, marital status, and physical activity. Associations between diet and RGWG differed by gestational period. CONCLUSION: A better quality diet, as measured by MDQS, was associated with appropriate GWG during pregnancy in the PRINCESA cohort.
Assuntos
Trajetória do Peso do Corpo , Dieta Saudável/estatística & dados numéricos , Ganho de Peso na Gestação , Adulto , Índice de Massa Corporal , Estudos de Coortes , Dieta/efeitos adversos , Feminino , Humanos , México , Razão de Chances , Sobrepeso/etiologia , Gravidez , Complicações na Gravidez/etiologia , Adulto JovemRESUMO
BACKGROUND: Environmental exposures are associated with a number of outcomes including adverse pregnancy outcomes. Although inflammation is hypothesized to play a role, the mechanistic pathways between environmental exposures and adverse health outcomes, including associations between exposures and longitudinal measures of systemic and reproductive tract inflammation, need elucidation. OBJECTIVES: This study was conducted to evaluate whether exposure to air pollution is associated with immunologic responses in the systemic circulation and lower reproductive tract, and to evaluate whether systemic and reproductive tract immunologic responses are similar. METHODS: We quantified repeated measures of cytokines from cervico-vaginal exudates and serum obtained concurrently among 104 women with term pregnancies and estimated PM10 and CO exposure using the monitor nearest each participant's residence. Serum and cervico-vaginal cytokines were compared using Wilcoxon signed-ranks test and Spearman rank correlations for select gestational months. We used intraclass correlation coefficients (ICCs) to quantify reproducibility of cytokine measurements, and Tobit regression to estimate associations between air pollution and cytokines. RESULTS: Median cervico-vaginal levels of IL-6, Eotaxin, IP-10, MCP-1, MIP-1α, MIP-1ß, and TNFα were higher than corresponding serum cytokines, significantly so for IL-6 and IP-10. Cervico-vaginal and serum cytokines were not correlated, but cytokines from the same fluid were correlated. ICCs for most serum cytokines were ≤0.40, while ICCs were higher in cervico-vaginal cytokines (range 0.52-0.83). IP-10 and Eotaxin had the highest ICCs for both cytokine sources. In adjusted models, PM10 was positively associated with serum cytokines IL-6, IP-10, MIP-1ß and Eotaxin but inversely associated with cervico-vaginal cytokine TNFα, IP-10, MIP-1ß, MCP-1 and Eotaxin, controlling for false discovery rate. CO was inversely associated with cervico-vaginal TNFα, IL-6, MIP-1ß, MCP-1 and Eotaxin. CONCLUSIONS: Inflammatory processes are compartment-specific. Systemic inflammatory markers may provide information on immunologic processes and response to environmental exposures, but are not proxies for lower reproductive tract inflammation.
Assuntos
Poluição do Ar/estatística & dados numéricos , Citocinas/metabolismo , Monitoramento Ambiental , Exposição Materna/estatística & dados numéricos , Adulto , Biomarcadores/metabolismo , Exposição Ambiental , Feminino , Humanos , Inflamação , México , Gravidez , Adulto JovemRESUMO
BACKGROUND: Previous animal and ecological studies have provided evidence for an earlier sexual maturation in females in relation to fluoride exposure; however, no epidemiological studies have examined the association between fluoride exposure and pubertal development in both boys and girls using individual-level biomarkers of fluoride. Capitalizing on an ongoing Mexican birth cohort study, we examined the association between concurrent urinary fluoride levels and physical markers of pubertal development in children. METHODS: We conducted a cross-sectional study of 157 boys and 176 girls at age 10-17 years living in Mexico City. We used ion-selective electrode-based diffusion methods to assess fluoride levels in urine, adjusting for urinary specific gravity. Pubertal stages were evaluated by a trained physician. Associations of fluoride with pubertal stages and age at menarche were studied using ordinal regression and Cox proportional-hazard regression, respectively. RESULTS: In the entire sample, the geometric mean and interquartile range (IQR) of urinary fluoride (specific gravity adjusted) were 0.59 mg/L and 0.31 mg/L, respectively. In boys, our analysis showed that a one-IQR increase in urinary fluoride was associated with later pubic hair growth (OR = 0.71, 95% CI: 0.51-0.98, p = 0.03) and genital development (OR = 0.71, 95% CI: 0.53-0.95, p = 0.02). No significant associations were found in girls, although the direction was negative. CONCLUSIONS: Childhood fluoride exposure, at the levels observed in our study, was associated with later pubertal development among Mexican boys at age 10-17 years. Further research is needed to confirm these findings.