Association of sleep duration and quality with serum testosterone concentrations among men and women: NHANES 2011-2016

BACKGROUND

The association between testosterone concentrations and sleep duration is poorly understood.

OBJECTIVE

To evaluate the association between sleep duration and quality with serum testosterone concentrations and its variation by sex and age.

METHODS

Data were analyzed for 8748 men and women (≥20 years old) who participated in the cycles of the National Health and Nutrition Examination Survey 2011-2016, a cross-sectional study. Total testosterone (ng/dL) was measured and categorized (low, moderate, and high) based on established cut-offs for men and its tertile distribution among women. Sleep duration was classified as ≤6, 7-8, and ≥9 h. Sleep quality was classified as poor or good based on the frequency of trouble falling or staying asleep or sleeping too much. Weighted multivariable adjusted and multinomial logistic regression models were conducted to assess these associations.

RESULTS

The association between sleep duration and testosterone concentrations, varied according to sex and age. Sleep deprivation (≤6 h) was associated with high testosterone (odds ratio = 3.62; 95% confidence interval: 1.37, 9.53) among young men (20-40 years old); meanwhile, middle-aged men (41-64 years old) who reported more sleep duration had low testosterone (odds ratio = 2.03; 95% confidence interval: 1.10, 3.73). A J-shaped association between sleep duration and low testosterone (odds ratio≤6 h  = 1.57; 95% confidence interval: 1.10, 2.27; odds ratio≥9  h  = 2.06; 95% confidence interval: 1.18, 3.59) was observed in women aged 41-64 years. We did not find any association with sleep quality.

CONCLUSION

The association of sleep duration with serum testosterone concentrations varies with sex and age group. Prospective studies are warranted to confirm these sex and age group differences.

Maternal urinary fluoride during pregnancy and birth weight and length: Results from ELEMENT cohort study

Epidemiological studies assessing prenatal fluoride exposure and anthropometry at birth are scarce, inconsistent and with methodological limitations. The aim of this study was to evaluate associations between maternal urinary fluoride (MUF) at each trimester of pregnancy and birth weight and length in 536 mother-child pairs in the Early Life Exposures in Mexico to Environmental Toxicants (ELEMENT) cohort study. MUF (mg/L) was measured using microdiffusion/fluoride-specific electrode from at least one trimester of pregnancy. Non-linear associations were assessed through segmented regression models (MUF and birth weight Z-score) and we used linear regression models for MUF and birth length Z-score. Models were adjusted for potential confounders including urinary creatinine concentrations as a covariate. Non-creatinine adjusted MUF levels at each trimester of pregnancy were 0.81, 0.86, and 0.82 mg/L, mean concentrations for first, second and third trimester, respectively. For birth weight, we identified a MUF breakpoint at 0.99, 0.68 and 0.58 mg/L, for first, second and third trimester of pregnancy, respectively. In the first trimester, an increase of 1 mg/L in MUF concentrations ≥0.99 mg/L was associated with an increase in weight Z-score at birth (β = 0.79; 95% CI: 0.10, 1.48; p = 0.02). Second trimester MUF (≥0.68 mg/L) was marginally associated with birth weight decrease (β = -0.25; 95% CI: -0.55, 0.04; p = 0.09) and third trimester MUF (≥0.58 mg/L) was significantly associated with birth weight decrease (β = -0.33; 95% CI: -0.63, -0.03; p = 0.03). We observed a linear and significant association between MUF and Z-score of length at birth only for the first trimester of pregnancy (β = 0.55; 95% CI: 0.07, 1.04; p < 0.02). Prenatal fluoride exposure was associated with birthweight z-score with different susceptibility windows. Our findings reinforce the hypothesis that maternal fluoride exposure may affect birth anthropometry.

Correction to 'ALOX5, LPA, MMP9 and TPO gene polymorphisms increase atherothrombosis susceptibility in middle-aged Mexicans'

[This corrects the article DOI: 10.1098/rsos.190775.].

ALOX5, LPA, MMP9 and TPO gene polymorphisms increase atherothrombosis susceptibility in middle-aged Mexicans

Atherothrombosis is the cornerstone of cardiovascular diseases and the primary cause of death worldwide. Genetic contribution to disturbances in lipid metabolism, coagulation, inflammation and oxidative stress increase the susceptibility to its development and progression. Given its multifactorial nature, the multiloci studies have been proposed as potential predictors of susceptibility. A cross-sectional study was conducted to explore the contribution of nine genes involved in oxidative stress, inflammatory and thrombotic processes in 204 subjects with atherothrombosis matched by age and gender with a healthy group (n = 204). To evaluate the possibility of spurious associations owing to the Mexican population genetic heterogeneity as well as its ancestral origins, 300 unrelated mestizo individuals and 329 Native Americans were also included. ALOX5, LPA, MMP9 and TPO gene polymorphisms, as well as their multiallelic combinations, were twice to four times more frequent in those individuals with clinical manifestations of atherothrombosis than in the healthy group. Once adjusting for population stratification was done, these differences remained. Our results add further evidence on the contribution of ALOX5, LPA, MMP9 and TPO polymorphisms to atherothrombosis development in the middle-aged group, emphasizing the multiethnic studies in search of gene risk polymorphisms.

High Relative Abundance of Lactobacillus reuteri and Fructose Intake are Associated with Adiposity and Cardiometabolic Risk Factors in Children from Mexico City

In Mexico, 3 of 10 children are overweight. Fructose intake and relative abundance (RA) of Lactobacillus reuteri (L. reuteri) in the intestinal microbiota are associated with obesity and diabetes in adults, but studies in children are limited. This study evaluates the association between fructose intake and L. reuteri RA with adiposity and cardiometabolic risk markers in Mexican children dietary information, microbiota profiles, adiposity indicators (Body Mass Index, BMI and Waste Circumference, WC), and cardiometabolic markers were analyzed in 1087 children aged 6–12 years. Linear regression and path analysis models were used. High-tertile fructose intake and L. reuteri RA were positively associated with BMI (β_{Tertil 3 vs. Tertil 1}= 0.24 (95% CI, 0.04; 0.44) and β_{T3 vs. T1} = 0.52 (95% CI, 0.32; 0.72)) and WC (β_{T3 vs. T1} = 2.40 (95% CI, 0.93; 3.83) and β_{T3 vs. T1} = 3.40 (95% CI, 1.95; 4.90)), respectively. Also, these factors mediated by adiposity were positively correlated with high triglycerides and insulin concentrations and HOMA-IR (p ≤ 0.03) and negatively associated with HDL-C concentration (p < 0.01). High-tertile fructose intake and L. reuteri RA were directly associated with adiposity and indirectly associated though adiposity with metabolic disorders in children. In conclusion, fructose intake and L. reuteri RA were directly associated with adiposity and indirectly associated with metabolic disorders in children, mediated by adiposity.

State of Children Environmental Health Research in Latin America

Background:

Promotion of biomedical research along with the development of evidence-based prevention policies have been suggested as an effective way to reduce environmental risks for children’s health in Latin America. However, there is little information on the current state of childhood environmental health research, which might help identify its strengths and limitations, as well as to design a strategy to improve the future of child environmental health research in the region.

Objective:

To describe the current state of environmental health research on children exposed to environmental pollutants in Latin America.

Methodology:

We performed a comprehensive search of published peer-reviewed environmental health articles (1994–2014), dealing with the exposure of Latin American children to chemical compounds. We described the type of studies and their research topics, and identified networks of co-authors. We also analyzed the relationship between research funding sources and the impact factor (IF) of the journal where research was published.

Results:

The average number of publications was about 20 per year. Mexico and Brazil produced almost 70% of the 409 identified papers. The most studied contaminant was lead, but research on this element has declined since 2005. Retrospective studies were the most frequent, and also showed a decreasing trend. Most studies did not assess health effects. Four groups of leading investigators and two collaboration models for scientific production were identified. Except for Mexico, there was very little collaboration with North American and European countries. Compared to articles that did not report financial support, those that received international funding had on average an IF around 7, and those with national funding reached a mean IF near 3.

Conclusion:

There is a limited number of publications and insufficient collaboration between Latin-American scientists. It is necessary to identify strategies to stimulate South-South-North alliances and strengthen the scarce research on the environmental health of children in the region.

Smoking and prostate cancer: a life course analysis

Background

Inconsistent associations between smoking status and prostate cancer (PC) could be due to exposure assessment error. Reconstructing smoking behaviors over the life course could reduce exposure assessment error.

Methods

As part of a case-control study, we identified 402 incident and histologically confirmed PC cases that were matched by age (±5 years) to 805 population controls. Through direct interview, we obtained information about: age at smoking onset, intensity and frequency of cigarette smoking at different life stages, and smoking cessation age. Smoking status at interview and average smoking index over the lifetime (packs/year) were estimated. Life course smoking patterns were obtained applying the k-means+ method for longitudinal data to the smoking index (pack/year) for each life stage.

Results

Two life-course smoking patterns were identified among ever smokers: “pattern A” characterized by males who reported low and constant smoking intensity (87.8%), and “pattern B” (12.2%) males with an initial period of low intensity, followed by an increase during the second period. Compared to never smokers, pattern B was associated with higher poorly differentiated PC, (OR 2.30; 95% CI 1.21–4.38). No association was observed with average smoking index.

Conclusion

Life course smoking patterns seem to capture the smoking variability during life course and reduce the likelihood of reverse causation. Using this assessment strategy our findings support the potential role of tobacco smoking in PC, particularly poorly differentiated PC. Prospective studies with comprehensive smoking history during the lifetime are needed to confirm these findings.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4065-7) contains supplementary material, which is available to authorized users.

Prostate cancer mortality according to marginalization status in Mexican states from 1980 to 2013

OBJECTIVE

To assess prostate cancer (PC) mortality in Mexico from 1980 to 2013, according to the state marginalization level.

MATERIALS AND METHODS

Using age-adjusted rates in men ≥ 40 years old, we estimated trends and age-cohort-period effects of PC mortality from 1980-2013 according to state marginalization status by using a joinpoint regression model and a Poisson regression model proposed by Holford.

RESULTS

The PC mortality risk has increased nationwide at a constant rate (2% annually) during the past 13 years. The highest annual increase was observed among states with very high (4.4%) and high (7.7%) marginalization rates. In contrast, states with very low levels of marginalization showed a significant reduction of 1.5% per year. The main changes were observed in the 1945-1950 birth year cohorts.

CONCLUSIONS

Differences in PC mortality across regions of Mexico may reflect differences in the timing of the diagnosis and treatment of PC.

Tendencias en la mortalidad por cáncer en México de 1980 a 2011

Objetivo. Evaluar las tendencias de mortalidad por cáncer en México entre 1980 y 2011. Material y métodos. Se calcularon las tasas de mortalidad ajustadas por edad y sexo para todos los cánceres y para las 15 localizaciones más frecuentes mediante el método directo y tomando como población estándar la población mundial de 2010. Las tendencias en las tasas de mortalidad y el cambio porcentual anual para cada tipo de cáncer se estimaron a través de un modelo de regresión joinpoint. Resultados. A partir de 2004 y como consecuencia de la reducción de la mortalidad por cáncer de pulmón (-3.2% en hombres y -1.8% en mujeres), estómago (-2.1% en hombres y -2.4% en mujeres) y cérvix (-4.7%), se observó una disminución significativa (~1% anual) en la mortalidad por cáncer en general tanto en el grupo de todas las edades como en el de 35 a 64 años para ambos sexos. La mortalidad por otros cánceres como el de mama y el de ovario, en las mujeres o el de próstata, en los hombres, mostró un aumento sostenido. Conclusiones. Algunas de las reducciones en la mortalidad por cáncer pueden ser parcialmente atribuidas a la efectividad de los programas de prevención establecidos. Sin embargo, se requiere implementar registros adecuados de cáncer con base poblacional para evaluar el impacto real de estos programas, así como diseñar y evaluar intervenciones innovadoras que permitan desarrollar políticas de prevención más costo-efectivas.

[Cancer mortality trends in Mexico, 1980-2011]

OBJECTIVE

To evaluate trends in cancer mortality in Mexico between 1980-2011.

MATERIAL AND METHODS

Through direct method and using World Population 2010 as standard population, mortality rates for all cancers and the 15 most frequent locations, adjusted for age and sex were calculated. Trends in mortality rates and annual percentage change for each type of cancer were estimated by joinpoint regression model.

RESULTS

As a result of the reduction in mortality from lung cancer (-3.2% -1.8% in men and in women), stomach (-2.1% -2.4% in men and in women) and cervix (-4.7%); since 2004 a significant (~1% per year) decline was observed in cancer mortality in general, in all ages, and in the group of 35-64 years of both sexes. Other cancers such as breast and ovarian cancer in women; as well as for prostate cancer in men, showed a steady increase.

CONCLUSIONS

Some of the reductions in cancer mortality may be partially attributed to the effectiveness of prevention programs. However, adequate records of population-based cancer are needed to assess the real impact of these programs; as well as designing and evaluating innovative interventions to develop more cost-effective prevention policies.

Assessing phytochemical intake in a group of Mexican women

OBJECTIVE

Identify the content of selected phytochemicals (PHYs) in Mexican foods and evaluate the reliability of a food frequency questionnaire (FFQ) in assessing PHYs intake among Mexican women.

MATERIAL AND METHODS

Values for PHYs content were obtained from four different data sets. PHYs intake was assessed in 50 women of reproductive age enrolled in a longitudinal cohort study. Values were obtained from a FFQ administered twice, one year apart in order to evaluate its reliability. Selected PHYs included flavonol (FOL), flavones (FES), flavanol (FAL), secoisolariciresinol (SE), matairesinol (MA), lariciresinol (LA), pinoresinol (PI), cynamic acid (CA) and coumestrol (CU).

RESULTS

Daily PHYs intake ranged from 1.3 microg +/- 0.9 for MA to 116.3 +/- 43.8 mg for CA. The adjusted correlation coefficients ranged from 0.17 for FAL to 0.47 for LA. Pinto beans, oranges, hot sauce, broccoli, apples and onions were the main sources of the selected PHYs daily intake.

DISCUSSION

The results of this study contribute to our understanding of the consumption of PHYs in the Mexican diet, and would help evaluate their potential health impact.

Nutritional factors and breast cancer in Mexico

Breast cancer (BC) morbidity and mortality in Mexico are on the rise, affecting younger women with more frequency. Nutritional factors are often mentioned as determinants of BC but their relevance is not well established in Latin-American countries, where dietary habits show great variation. From a study population previously assembled in Mexico City, 141 histologically confirmed cases of BC were matched by age (+/-3 yr) to an equal number of hospital controls. A food frequency questionnaire was administered to all subjects and the risk of BC was estimated in relation to the intake of selected nutrients. The findings of this study show a protective effect against BC due to a high intake of polyunsaturated fat (odds ratio, OR = 0.10, 95% CI = 0.02-0.40, P for trend = 0.001) and vitamin E (OR = 0.10, 95% CI = 0.02-0.44, P for trend = 0.003) among postmenopausal women. In addition, our findings also suggest that a high intake of total fiber (OR = 0.29, 95% CI = 0.08-1.10, P for trend = 0.080) and carotenes (OR = 0.42, 95% CI = 0.16-1.14, P for trend = 0.088) lowers BC risk among premenopausal women. The relationship between the intake of nutrients and BC risk needs further confirmation.

Intrauterine lead exposure and preterm birth

The objective of this study was to determine the risk of preterm birth in relation to umbilical cord blood lead levels (UCL) among primiparous and multiparous women. A case-cohort study was performed in Mexico City during 1995. A total of 459 full-term births was compared with 161 preterm births (before 37 gestational weeks). Mothers were interviewed before the delivery about their reproductive histories and other related factors of preterm birth. Lead was determined by atomic absorption spectrophotometry. Lead levels were higher in primiparous women who had a preterm birth than in primiparous women with a full-term birth (9.77+/-2.0 microgram/dl vs 8.24+/-2.15 microgram/dl); this difference was marginally significant. After adjusting for other known preterm birth risk factors, the frequency of preterm birth was almost three times higher among women who had UCL levels greater or equal to 5.1 microgram/dl compared to those who had UCL levels lower than 5.1 microgram/dl. This difference was not observed among multiparous women. Our results suggest that intrauterine lead exposure may be associated with preterm birth in first deliveries but not in subsequent ones.