In utero exposure to DDT and incidence of diarrhea among boys from tropical Mexico.

BACKGROUND: A higher incidence rate (IR) of acute gastrointestinal (GI) infections associated with prenatal exposure to p,p'-DDE was suggested by the results in two studies. Given the high mortality rate due to childhood diarrhea in some countries with ongoing use of DDT, additional data on this association is relevant for those making decisions about vector-borne disease control. OBJECTIVE: To evaluate whether higher levels of prenatal exposure to p,p'-DDE and p,p'-DDT increase the risk of having diarrhea in a birth cohort of boys from tropical Mexico. METHODS: Our analysis was based on 747 boys whose exposure was measured in maternal serum collected at delivery (2002-2003). Mothers reported the number of diarrhea episodes of their children during in-person interviews. The median age of the children at their last interview was 21.4 months. Poisson regression models were fitted to estimate adjusted incidence rate ratios (aIRR) of diarrhea by levels of p,p'-DDE and p,p'-DDT. RESULTS: Overall, there were 1.7 episodes of diarrhea per child-year. Among those in the highest category of exposure (> 9µg DDE/g serum lipid), the aIRR for diarrhea was 1.14 (95% CI: 0.94, 1.30) compared to those in the lowest category of exposure (≤ 3µg/g). Among boys living in the urban area, the corresponding aIRR was 1.39 (95% CI: 1.07-1.80). Among rural boys, no associations emerged. CONCLUSION: Although the results were consistent with a small positive association, the overall estimate was not precise. While urban boys in this study appeared to be more susceptible to DDE-associated diarrhea, a ready explanation for such increased susceptibility was not apparent.

[CONSUMPTION OF OMEGA- 3 FATTY ACIDS AND DEPRESSIVE SYMPTOMS IN COLLEGE STUDENTS FROM SONORA, MEXICO]. / CONSUMO DE ÁCIDOS GRASOS OMEGA-3 Y SÍNTOMAS DEPRESIVOS EN UNIVERSITARIOS DE SONORA, MÉXICO.

INTRODUCTION: recent studies suggest that low serum levels of polyunsaturated fatty acids omega-3 are associated with a higher prevalence of depression. OBJECTIVE: to evaluate whether low consumption of Omega-3 fatty acids is associated with a higher prevalence of depressive symptoms in a sample of college students from the Northwest of Mexico, and to assess the potential effect modification by alcohol consumption. METHODS: we conducted a cross-sectional study in a sample of 706 college students (males and females) aged 18 to 24. The presence of depressive symptoms was identified with the Depression Scale of the Center for Epidemiologic Studies (CES-D), using a cutoff point of ≥ 24. The intake of omega-3 was obtained by a food frequency questionnaire validated for Mexican population. We estimated the weekly intake of alpha-linolenic fatty acid (ALA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) derived from the diet in mg/g of food. The association between omega-3 from diet and the presence of depressive symptoms was assessed using logistic regression models adjusted for potential confounders. RESULTS: 67% of the participants were females; 16.6% were classified as having depressive symptoms. A low intake of ALA and EPA + DHA was not associated with depressive symptoms before and after adjusting for confounders. Median levels of ALA (from nuts only) were significantly lower among those with depressive symptoms compared to those without these symptoms. CONCLUSIONS: in this population of Mexican college students, a low intake of omega-3 fatty acids was not associated with depressive symptoms. The potential association between nut consumption and depressive symptoms deserve more attention.

Introducción: estudios recientes sugieren que los niveles bajos de acidos grasos poliinsaturados omega-3 se relacionan con una mayor prevalencia de depresion; sin embargo, los resultados no son concluyentes. Objetivo: evaluar la asociacion entre el bajo consumo de acidos grasos omega-3 y la presencia de sintomas depresivos en jovenes universitarios del noroeste de Mexico. Métodos: se realizo un estudio transversal en una muestra de 706 universitarios de 18 a 24 anos de edad de ambos sexos. La presencia de sintomatologia depresiva se estimo con la escala de Depresion del Centro de Estudios Epidemiologicos (CES-D) empleando un punto de corte ≥ 24. El consumo semanal de acidos grasos alfalinolenico (ALA) y de eicosapentaenoico (EPA) mas docosahexaenoico (DHA) en mg/g de alimento se estimo por medio de un cuestionario de frecuencia de consumo de alimentos validado para la poblacion mexicana. La asociacion del consumo de omega-3 con la presencia de sintomas depresivos se evaluo con modelos de regresion logistica. Resultados: el 67% de los participantes fueron mujeres; en general, el 16,6% presentaron sintomatologia depresiva. El consumo bajo de ALA y EPA + DHA no se asocio con mayor prevalencia de sintomatologia depresiva antes y despues de ajustar por confusores. En aquellos casos con sintomatologia depresiva, los niveles ALA derivados solo de las nueces fueron significativamente menores. Conclusiones: en esta poblacion no se observo asociacion entre el bajo consumo de acidos grasos omega-3 y la sintomatologia depresiva. La posible asociacion entre el consumo de nueces y la sintomatologia depresiva requiere de mas estudios.

Consumo de ácidos grasos omega-3 y síntomas depresivos en universitarios de Sonora, México / Consumption of omega- 3 fatty acids and depressive symptoms in college students from Sonora, Mexico

Introducción: estudios recientes sugieren que los niveles bajos de ácidos grasos poliinsaturados omega-3 se relacionan con una mayor prevalencia de depresión; sin embargo, los resultados no son concluyentes. Objetivo: evaluar la asociación entre el bajo consumo de ácidos grasos omega-3 y la presencia de síntomas depresivos en jóvenes universitarios del noroeste de México. Métodos: se realizó un estudio transversal en una muestra de 706 universitarios de 18 a 24 años de edad de ambos sexos. La presencia de sintomatología depresiva se estimó con la escala de Depresión del Centro de Estudios Epidemiológicos (CES-D) empleando un punto de corte ≥ 24. El consumo semanal de ácidos grasos alfalinolénico (ALA) y de eicosapentaenóico (EPA) más docosahexaenóico (DHA) en mg/g de alimento se estimó por medio de un cuestionario de frecuencia de consumo de alimentos validado para la población mexicana. La asociación del consumo de omega-3 con la presencia de síntomas depresivos se evaluó con modelos de regresión logística. Resultados: el 67% de los participantes fueron mujeres; en general, el 16,6% presentaron sintomatología depresiva. El consumo bajo de ALA y EPA + DHA no se asoció con mayor prevalencia de sintomatología depresiva antes y después de ajustar por confusores. En aquellos casos con sintomatología depresiva, los niveles ALA derivados solo de las nueces fueron significativamente menores. Conclusiones: en esta población no se observó asociación entre el bajo consumo de ácidos grasos omega-3 y la sintomatología depresiva. La posible asociación entre el consumo de nueces y la sintomatología depresiva requiere de más estudios (AU)

Introduction: recent studies suggest that low serum levels of polyunsaturated fatty acids omega-3 are associated with a higher prevalence of depression. Objective: to evaluate whether low consumption of Omega-3 fatty acids is associated with a higher prevalence of depressive symptoms in a sample of college students from the Northwest of Mexico, and to assess the potential effect modification by alcohol consumption. Methods: we conducted a cross-sectional study in a sample of 706 college students (males and females) aged 18 to 24. The presence of depressive symptoms was identified with the Depression Scale of the Center for Epidemiologic Studies (CES-D), using a cutoff point of ≥ 24. The intake of omega-3 was obtained by a food frequency questionnaire validated for Mexican population. We estimated the weekly intake of alpha-linolenic fatty acid (ALA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) derived from the diet in mg/g of food. The association between omega-3 from diet and the presence of depressive symptoms was assessed using logistic regression models adjusted for potential confounders. Results: 67% of the participants were females; 16.6% were classified as having depressive symptoms. A low intake of ALA and EPA + DHA was not associated with depressive symptoms before and after adjusting for confounders. Median levels of ALA (from nuts only) were significantly lower among those with depressive symptoms compared to those without these symptoms. Conclusions: in this population of Mexican college students, a low intake of omega-3 fatty acids was not associated with depressive symptoms. The potential association between nut consumption and depressive symptoms deserve more attention (AU)

Prenatal exposure to p,p'-DDE and p,p'-DDT in relation to lower respiratory tract infections in boys from a highly exposed area of Mexico.

BACKGROUND: Prenatal exposure to 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE), the major breakdown product of DDT, has been associated with recurrent lower respiratory tract infections (LRTIs) in infants. However, epidemiological investigations are limited. OBJECTIVE: To assess the association of prenatal exposure to p,p'-DDE and p,p'-DDT with the occurrence of LRTI in boys from Chiapas, a highly exposed area of Mexico. METHODS: We analyzed data from 747 singleton boys whose prenatal exposure to p,p'-DDE and p,p'-DDT was determined in maternal serum drawn at delivery (2002-2003). LRTI (i.e., pneumonia, bronchiolitis, and other illness of the bronchi) experienced by the children were reported by their mothers during in-person interviews. The median age of the children when they were last seen was 21.4 months (quartiles 19.1 and 25.3 months). RESULTS: Median exposure to p,p'-DDE in this population was higher (2.7 µg/g lipid) than recent U.S. levels (0.20 µg/g). There were 0.19 episodes of LRTI per child-year. After adjusting for potential confounders, children in the highest category of p,p'-DDE (>9.00 µg/g) exposure compared to those in the lowest (≤ 3.00 µg/g) had an adjusted incidence rate ratio (aIRR) of LRTI of 0.77 (95% confidence interval [CI], 0.41-1.46). The corresponding aIRR for p,p'-DDT (≥ 2.00 µg/g compared to ≤ 0.25 µg/g) was 0.65 (95% CI: 0.30-1.39). CONCLUSION: An association of prenatal exposure to p,p'-DDE and p,p'-DDT with LRTI during childhood was not supported in this population with relatively high levels of exposure.

Prenatal exposure to the major DDT metabolite 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and growth in boys from Mexico.

Recent data suggest that prenatal exposure to p,p'-DDE may reduce height and increase body mass index (BMI) in childhood, thus potentially raising the risk of adult health problems. The association between prenatal DDE exposure and growth was evaluated in 788 boys from Chiapas, an area of Mexico where DDT was recently used. The median DDE levels in maternal serum at birth (2002-2003) were 2.7 microg/g lipid. 2633 measurements of height (cm) and weight (kg) were obtained in 2004-2005. The median age of the children during follow-up was 18 months (quartiles 14 and 22 months). Height and body mass index (kg/m(2)) were age-standardized and expressed as standard deviation scores (SDS). Multivariate random-effect models for longitudinal data were fitted and predicted height and BMI SDS were estimated from the adjusted models. Overall, associations between prenatal DDE level and height or BMI SDS at any given age were not observed. For example, the predicted values showed that children with the highest exposure (DDE: >9.00 microg/g) compared to those least exposed (DDE: <3.01 microg/g) grew similarly and they had a BMI SDS similar to the referent group. The results do not support the prior findings of an association of DDE exposure with childhood height or BMI.